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Nearest star system to the Sun
Alpha Centauri AB[note 1]
Alpha Centauri AB is the bright star to the left, which forms a triple star system with Proxima Centauri, circled in red. The bright star system to the right is Beta Centauri.
Epoch J2000.0 Equinox J2000.0
Constellation Centaurus
Alpha Centauri A
-60° 50′ 02.3737″[1]
+0.01[2]
Alpha Centauri B
G2V[3]
U-B colour index
B-V colour index
K1V[3]
Radial velocity (Rv) [4] km/s
Proper motion (?) RA: -3679.25[1] mas/yr
Dec.: 473.67[1] mas/yr
Parallax (?) 754.81 ± 4.11[1] mas
Distance 4.37[5] ly
Absolute magnitude (MV) 4.38[6]
Mass 1.100[7] M☉
Radius [8] R☉
Luminosity 1.519[7] L☉
Surface gravity (log g) 4.30[9] cgs
Temperature 5,790[7] K
Metallicity [Fe/H] 0.20[7] dex
Rotation [10]
Rotational velocity (v sin i) [10] km/s
Luminosity 0.5002[7] L☉
Metallicity 0.23[7]
Rotation 36[11] days
Age [13] Gyr
Orbit[14]
Primary A
Companion B
Period (P) yr
Eccentricity (e)
Inclination (i) °
(secondary) °
Gliese 559, FK5 538, CD-60°5483, CCDM J14396-6050, GC 19728
? Cen A: Rigil Kentaurus, Rigil Kent, ?1 Centauri, HR 5459, HD 128620, GCTP 3309.00, LHS 50, SAO 252838, HIP 71683
? Cen B: Toliman, ?2 Centauri, HR 5460, HD 128621, LHS 51, HIP 71681
Database references
SIMBAD AB
Exoplanet Archive data
ARICNS data
Extrasolar Planets
Encyclopaedia data
Alpha Centauri is the closest star system and closest planetary system to Earth's Solar System at 4.37 light-years (1.34 parsecs) from the Sun. The name is Latinized from ? Centauri, and abbreviated Alpha Cen or ? Cen. It is a triple star system, consisting of three stars Centauri A (officially Rigil Kentaurus),[15] ? Centauri B (officially Toliman),[15] and ? Centauri C (officially Proxima Centauri).[15]
Alpha Centauri A and B are Sun-like stars (Class G and K), and together they form the binary star Alpha Centauri AB. To the naked eye, the two main components appear to be a single star with an apparent magnitude of -0.27, the brightest star in the southern constellation of Centaurus and the third-brightest in the night sky, outshone only by Sirius and Canopus.
Alpha Centauri A has 1.1 times the mass and 1.519 times the luminosity of the Sun, while Alpha Centauri B is smaller and cooler, at 0.907 times the Sun's mass and 0.445 times its luminosity.[16] The pair orbit around a common centre with an orbital period of 79.91 years.[17] Their elliptical orbit is eccentric, so that the distance between A and B varies from 35.6 AU (astronomical units), or about the distance between Pluto and the Sun, to 11.2 AU, or about the distance between Saturn and the Sun.
Alpha Centauri C, or Proxima Centauri, is a small and faint red dwarf (Class M). Though not visible to the naked eye, Proxima Centauri is the closest star to the Sun at a distance of 4.24 light-years (1.30 pc), slightly closer than Alpha Centauri AB. Currently, the distance between Proxima Centauri and Alpha Centauri AB is about 13,000 astronomical units (0.21 ly),[18] equivalent to about 430 times the radius of Neptune's orbit.
Proxima Centauri has two planets: Proxima b, an Earth-sized exoplanet in the habitable zone discovered in 2016; and Proxima c, a super-Earth 1.5 AU away, which is possibly surrounded by a huge ring system, discovered in 2019. Alpha Centauri B has a disproven planet (Bb).
Alpha Centauri is the brightest object in the constellation of Centaurus (top left).
? Centauri (Latinised to Alpha Centauri) is the system's designation given by Johann Bayer in 1603. It bears the traditional name Rigil Kentaurus, which is a Latinisation of the Arabic name  Rijl al-Qinrus, meaning 'the Foot of the Centaur'.[19][20] The name is frequently abbreviated to Rigil Kent or even Rigil, though the latter name is better known for Beta Orionis (Rigel).[21]
An alternative name found in European sources, Toliman, is an approximation of the Arabic  a?-?al?m?n (in older transcription, a?-?hal?m?n), meaning 'the (two male) Ostriches', an appellation Zakariya al-Qazwini had applied to Lambda and Mu Sagittarii, also in the southern hemisphere.[22]
A third name that has been applied is Bungula , of obscure origin. Allen can only surmise it may have been coined from the Greek letter beta (?) and Latin ungula 'hoof'.[21]
Alpha Centauri C was discovered in 1915 by Robert T. A. Innes,[23] who suggested that it be named Proxima Centaurus,[24] from Latin 'the nearest [star] of Centaurus'.[25] The name Proxima Centauri later became more widely used and is now listed by the IAU as the approved proper name.[26][27]
In 2016, the Working Group on Star Names of the International Astronomical Union (IAU),[28] having decided to attribute proper names to individual component stars rather than to multiple systems,[29] approved the name Rigil Kentaurus as being restricted to Alpha Centauri A and the name Proxima Centauri for Alpha Centauri C.[15] On 10 August 2018, the IAU approved the name Toliman for Alpha Centauri B.[30]
Stellar system
Alpha Centauri is a triple star system, with its two main stars, Alpha Centauri A and Alpha Centauri B, being a binary component. The AB designation, or older A×B, denotes the mass centre of a main binary system relative to companion star(s) in a multiple star system.[31]AB-C refers to the component of Proxima Centauri in relation to the central binary, being the distance between the centre of mass and the outlying companion. Because the distance between Proxima (C) and either of Alpha Centauri A or B is similar, the AB binary system is sometimes treated as a single gravitational object.[32]
Orbital properties
Apparent and true orbits of Alpha Centauri. The A component is held stationary, and the relative orbital motion of the B component is shown. The apparent orbit (thin ellipse) is the shape of the orbit as seen by an observer on Earth. The true orbit is the shape of the orbit viewed perpendicular to the plane of the orbital motion. According to the radial velocity vs. time,[14] the radial separation of A and B along the line of sight had reached a maximum in 2007, with B being further from Earth than A. The orbit is divided here into 80 points: each step refers to a timestep of approx. 0.99888 years or 364.84 days.
The A and B components of Alpha Centauri have an orbital period of 79.91 years.[17] Their orbit is moderately eccentric, e = 0.5179;[17] their closest approach or periastron is 11.2 AU (1.68 billion km), or about the distance between the Sun and Saturn; and their furthest separation or apastron is 35.6 AU (5.33 billion km), about the distance between the Sun and Pluto.[17] The most recent periastron was in August 1955 and the next will occur in May 2035; the most recent apastron was in May 1995 and will next occur in 2075.
Viewed from Earth, the apparent orbit of A and B means that their separation and position angle (PA) are in continuous change throughout their projected orbit. Observed stellar positions in 2019 are separated by 4.92 arcsec through the PA of 337.1°, increasing to 5.49 arcsec through 345.3° in 2020.[17] The closest recent approach was in February 2016, at 4.0 arcsec through the PA of 300°.[17][33] The observed maximum separation of these stars is about 22 arcsec, while the minimum distance is 1.7 arcsec.[34] The widest separation occurred during February 1976, and the next will be in January 2056.[17]
Alpha Centauri C is about 13,000 AU away from Alpha Centauri AB.[18][35][36] This is equivalent to 0.21 ly or 1.9 trillion km--about 5% the distance between Alpha Centauri AB and the Sun. Until 2017, measurements of its small speed and its trajectory were of too little accuracy and duration in years to determine whether it is bound to Alpha Centauri AB or unrelated.
Radial velocity measurements made in 2017 were precise enough to show that Proxima Centauri and Alpha Centauri AB are gravitationally bound.[18] The orbital period of Proxima Centauri is approximately years, with an eccentricity of 0.50 ± 0.08, much more eccentric than Mercury's. Proxima Centauri comes within of AB at periastron, and its apastron occurs at .[18]
The relative sizes and colours of stars in the Alpha Centauri system, compared to the Sun
Asteroseismic studies, chromospheric activity, and stellar rotation (gyrochronology) are all consistent with the Alpha Centauri system being similar in age to, or slightly older than, the Sun.[37] Asteroseismic analyses that incorporate tight observational constraints on the stellar parameters for the Alpha Centauri stars have yielded age estimates of Gyr,[7] Gyr,[38] 5.2 ± 1.9 Gyr,[39] 6.4 Gyr,[40] and Gyr.[41] Age estimates for the stars based on chromospheric activity (Calcium H & K emission) yield 4.4 ± 2.1 Gyr, whereas gyrochronology yields Gyr.[37]Stellar evolution theory implies both stars are slightly older than the Sun at 5 to 6 billion years, as derived by their mass and spectral characteristics.[35][42]
From the orbital elements, the total mass of Alpha Centauri AB is about 2.0 M☉[note 2]--or twice that of the Sun.[34] The average individual stellar masses are 1.09 M☉ and 0.90 M☉, respectively,[42] though slightly higher masses have been quoted in recent years, such as 1.14 M☉ and 0.92 M☉,[43] or totalling 2.06 M☉. Alpha Centauri A and B have absolute magnitudes of +4.38 and +5.71, respectively.
Alpha Centauri A, also known as Rigil Kentaurus, is the principal member, or primary, of the binary system. It is a solar-like main-sequence star with a similar yellowish colour,[44] whose stellar classification is spectral type G2 V;[3] it is about 10 percent more massive than the Sun,[7] with a radius about 22 percent larger.[8] When considered among the individual brightest stars in the sky (excluding the Sun), it is the fourth brightest at an apparent magnitude of -0.01, being slightly fainter than Arcturus at an apparent magnitude of -0.05.
The type of magnetic activity on Alpha Centauri A is comparable to that of the Sun, showing coronal variability due to star spots, as modulated by the rotation of the star. However, since 2005 the activity level has fallen into a deep minimum that might be similar to the Sun's historical Maunder Minimum. Alternatively, it may have a very long stellar activity cycle and is slowly recovering from a minimum phase.[45]
Alpha Centauri B, also known as Toliman, is the secondary star of the binary system. It is a main-sequence star of spectral type K1 V, making it more an orange colour than Alpha Centauri A;[44] it has around 90 percent the mass of the Sun and a 14 percent smaller diameter. Although it has a lower luminosity than A, Alpha Centauri B emits more energy in the X-ray band.[46] Its light curve varies on a short time scale, and there has been at least one observed flare.[46] It is more magnetically active than Alpha Centauri A, showing a cycle of compared to 11 years for the Sun, and about half the minimum-to-peak variation in coronal luminosity of the Sun.[45] Alpha Centauri B has an apparent magnitude of +1.35, slightly dimmer than Mimosa.[15]
Alpha Centauri C (Proxima Centauri)
Alpha Centauri C, better known as Proxima Centauri, is a small main-sequence red dwarf of spectral class M6 Ve. It has an absolute magnitude of +15.60, over 20,000 times fainter than the Sun. Its mass is calculated to be M☉.[47] It is the closest star to the Sun but is too faint to be visible to the naked eye.
Relative positions of Sun, Alpha Centauri AB and Proxima Centauri. Grey dot is projection of Proxima Centauri, located at the same distance as Alpha Centauri AB.
Location of Alpha Centauri in Centaurus
The two bright stars at the lower right are Alpha (right) and Beta Centauri (left, above antenna). A line drawn through them points to the four bright stars of the Southern Cross, just to the right of the dome of the Danish 1.54-metre telescope at La Silla Observatory in Chile.[48]
To the naked eye, Alpha Centauri AB appears to be a single star, the brightest in the southern constellation of Centaurus.[49] Their apparent angular separation varies over about 80 years between 2 and 22 arcsec (the naked eye has a resolution of 60 arcsec),[50] but through much of the orbit, both are easily resolved in binoculars or small telescopes.[51] At -0.27 apparent magnitude (combined for A and B magnitudes), Alpha Centauri is fainter only than Sirius and Canopus.[49] It is the outer star of The Pointers or The Southern Pointers,[51] so called because the line through Beta Centauri (Hadar/Agena),[52] some 4.5° west,[51] points to the constellation Crux--the Southern Cross.[51] The Pointers easily distinguish the true Southern Cross from the fainter asterism known as the False Cross.[53]
Alpha Centauri AB taken in daylight by holding a Canon Powershot S100 in line with the eyepiece of a 110 mm refractor. The photo is one of the best frames of a video. The double star is clearly visible.
South of about 29° S latitude, Alpha Centauri is circumpolar and never sets below the horizon.[note 3] North of about 29° N latitude, Alpha Centauri never rises. Alpha Centauri lies close to the southern horizon when viewed from the 29° N latitude to the equator (close to Hermosillo, Chihuahua City in Mexico, Galveston, Texas, Ocala, Florida and Lanzarote, the Canary Islands of Spain), but only for a short time around its culmination.[52] The star culminates each year at local midnight on 24 April and at local 9 p.m. on 8 June.[52][54]
As seen from Earth, Proxima Centauri is 2.2° southwest from Alpha Centauri AB, about four times the angular diameter of the Moon.[35] Proxima Centauri appears as a deep-red star of a typical apparent magnitude of 11.1 in a sparsely populated star field, requiring moderately sized telescopes to be seen. Listed as V645 Cen in the General Catalogue of Variable Stars Version 4.2, this UV Ceti-type flare star can unexpectedly brighten rapidly by as much as 0.6 magnitudes at visual wavelengths, then fade after only a few minutes.[55] Some amateur and professional astronomers regularly monitor for outbursts using either optical or radio telescopes.[56] In August 2015, the largest recorded flares of the star occurred, with the star becoming 8.3 times brighter than normal on 13 August, in the B band (blue light region).[57]
Alpha Centauri is inside the G-cloud, and its nearest known system is the binary brown dwarf system Luhman 16 at 3.6 ly (1.1 pc).[58]
Observational history
View of Alpha Centauri from the Digitized Sky Survey 2
Alpha Centauri is listed in the 2nd-century star catalog of Ptolemy. He gave its ecliptic coordinates, but texts differ as to whether the ecliptic latitude reads or .[59] (Presently the ecliptic latitude is , but it has decreased by a fraction of a degree since Ptolemy's time due to proper motion.) In Ptolemy's time, Alpha Centauri was visible from Alexandria, Egypt, at but, due to precession, its declination is now , and it can no longer be seen at that latitude. English explorer Robert Hues brought Alpha Centauri to the attention of European observers in his 1592 work Tractatus de Globis, along with Canopus and Achernar, noting:
Now, therefore, there are but three Stars of the first magnitude that I could perceive in all those parts which are never seene here in England. The first of these is that bright Star in the sterne of Argo which they call Canobus. The second [Achernar] is in the end of Eridanus. The third [Alpha Centauri] is in the right foote of the Centaure.[60]
The binary nature of Alpha Centauri AB was recognised in December 1689 by Jean Richaud, while observing a passing comet from his station in Puducherry. Alpha Centauri was only the second binary star to be discovered, preceded by Acrux.[61]
The large proper motion of Alpha Centauri AB was discovered by Manuel John Johnson, observing from Saint Helena, who informed Thomas Henderson at the Royal Observatory, Cape of Good Hope of it. The parallax of Alpha Centauri was subsequently determined by Henderson from many exacting positional observations of the AB system between April 1832 and May 1833. He withheld his results, however, because he suspected they were too large to be true, but eventually published them in 1839 after Friedrich Wilhelm Bessel released his own accurately determined parallax for 61 Cygni in 1838.[62] For this reason, Alpha Centauri is sometimes considered as the second star to have its distance measured because Henderson's work was not fully acknowledged at first.[62] (The distance of Alpha Centauri from the Earth is now reckoned at 4.396 ly or 41.59 trillion km.)
Alpha Centauri A is of the same stellar type G2 as the Sun, while Alpha Centauri B is a K1-type star.[63]
Later, John Herschel made the first micrometrical observations in 1834.[64] Since the early 20th century, measures have been made with photographic plates.[36]
By 1926, William Stephen Finsen calculated the approximate orbit elements close to those now accepted for this system.[34] All future positions are now sufficiently accurate for visual observers to determine the relative places of the stars from a binary star ephemeris.[65] Others, like D. Pourbaix (2002), have regularly refined the precision of new published orbital elements.[17]
Robert T. A. Innes discovered Proxima Centauri in 1915 by blinking photographic plates taken at different times during a proper motion survey. These showed large proper motion and parallax similar in both size and direction to those of Alpha Centauri AB, suggesting that Proxima Centauri is part of the Alpha Centauri system and slightly closer to Earth than Alpha Centauri AB. Lying 4.24 ly (1.30 pc) away, Proxima Centauri is the nearest star to the Sun.
Closest stars to the Sun
All components of Alpha Centauri display significant proper motion against the background sky. Over centuries, this causes their apparent positions to slowly change.[66] Proper motion was unknown to ancient astronomers. Most assumed that the stars are permanently fixed on the celestial sphere, as stated in the works of the philosopher Aristotle.[67] In 1718, Edmond Halley found that some stars had significantly moved from their ancient astrometric positions.[68]
In the 1830s, Thomas Henderson discovered the true distance to Alpha Centauri by analysing his many astrometric mural circle observations.[69][70] He then realised this system also likely had a high proper motion.[71][72][34] In this case, the apparent stellar motion was found using Nicolas Louis de Lacaille's astrometric observations of 1751-1752,[73] by the observed differences between the two measured positions in different epochs.
Calculated proper motion of the centre of mass for Alpha Centauri AB is about 3620 mas (milli-arcseconds) per year toward the west and 694 mas/y toward the north, giving an overall motion of 3686 mas/y in a direction 11° north of west.[74][note 4] The motion of the centre of mass is about 6.1 arcmin each century, or 1.02° each millennium. The velocity in the western direction is 23.0 km/s and in the northerly direction 4.4 km/s. Using spectroscopy the mean radial velocity has been determined to be around 22.4 km/s towards the Solar System.[74]
Since Alpha Centauri AB is almost exactly in the plane of the Milky Way as viewed from Earth, there are many stars behind them. In early May 2028, Alpha Centauri A will pass between the Earth and a distant red star, when there will be a 45% probability that an Einstein ring will be observed. Other conjunctions will also occur in the coming decades, allowing accurate measurement of proper motions and possibly giving information on planets.[74]
Predicted future changes
Distances of the nearest stars from 20,000 years ago until 80,000 years in the future
Animation showing motion of Alpha Centauri through the sky. (The other stars are held fixed for didactic reasons.) "Oggi" means today.
Based on the system's common proper motion and radial velocities, Alpha Centauri will continue to change its position in the sky significantly and will gradually brighten. For example, in about 6,200 AD, ? Centauri's true motion will cause an extremely rare first-magnitude stellar conjunction with Beta Centauri, forming a brilliant optical double star in the southern sky.[75] It will then pass just north of the Southern Cross or Crux, before moving northwest and up towards the present celestial equator and away from the galactic plane. By about 26,700 AD, in the present-day constellation of Hydra, Alpha Centauri will reach perihelion at 0.90 pc or 2.9 ly away,[76] though later calculations suggest that this will occur in 27,000 AD.[77] At nearest approach, Alpha Centauri will attain a maximum apparent magnitude of -0.86, comparable to present-day magnitude of Canopus, but it will still not surpass that of Sirius, which will brighten incrementally over the next 60,000 years, and will continue to be the brightest star as seen from Earth (other than the Sun) for the next 210,000 years.[78]
Confirmed planets
Proxima Centauri b
Proxima Centauri b is a terrestrial planet discovered in 2016 by astronomers at the European Southern Observatory. It has a minimum mass of 1.17 M? (Earth masses) and orbits approximately 0.049 AU from Proxima Centauri, placing it in the star's habitable zone.[79][80]
Proxima Centauri c
Proxima Centauri c was formally discovered and confirmed in 2020 and is a likely super-Earth or mini-Neptune.[81] It has a mass of roughly 7 M? and orbits about 1.49 AU from Proxima Centauri with a period of 1,928 days (5.28 yr). In June 2020, a large ring system encircling the planet was possibly detected.[82][83][84]
Controversial and hypothetical planets
Alpha Centauri Bb
In 2012, a planet around Alpha Centauri B was announced, Alpha Centauri Bb, but in 2015 a new analysis concluded that it almost certainly does not exist and was just a spurious artefact of the data analysis.[85][86][87]
Unconfirmed discovery
Whilst ruling out the existence of Alpha Centauri Bb, a possible transit of a separate exoplanet in 2013 was observed. The transit event could correspond to a planetary body with a radius around 0.92 R?. This planet would most likely orbit Alpha Centauri B with an orbital period of 20.4 days or less, with only a 5 percent chance of it having a longer orbit. The median of the likely orbits is 12.4 days with an impact parameter of around 0-0.3. Its orbit would likely have an eccentricity of 0.24 or less.[88] Like the probably spurious Alpha Centauri Bb, it likely has lakes of molten lava and would be far too close to Alpha Centauri B to harbour life.[89]
Around Proxima Centauri, a small spike with a periodicity of 5.15 days was found while revisiting Proxima Centauri b.[80] Were it a planetary companion, it would have to be at most 0.29 Earth masses, but it could also be random noise found in the data.
Hypothetical planets
Additional planets may exist in the Alpha Centauri system, either orbiting Alpha Centauri A or Alpha Centauri B individually, or in large orbits around Alpha Centauri AB. Because both stars are fairly similar to the Sun (for example, in age and metallicity), astronomers have been especially interested in making detailed searches for planets in the Alpha Centauri system. Several established planet-hunting teams have used various radial velocity or star transit methods in their searches around these two bright stars.[90] All the observational studies have so far failed to find evidence for brown dwarfs or gas giants.[90][91]
In 2009, computer simulations showed that a planet might have been able to form near the inner edge of Alpha Centauri B's habitable zone, which extends from 0.5 to 0.9 AU from the star. Certain special assumptions, such as considering that the Alpha Centauri pair may have initially formed with a wider separation and later moved closer to each other (as might be possible if they formed in a dense star cluster), would permit an accretion-friendly environment farther from the star.[92] Bodies around Alpha Centauri A would be able to orbit at slightly farther distances due to its stronger gravity. In addition, the lack of any brown dwarfs or gas giants in close orbits around Alpha Centauri make the likelihood of terrestrial planets greater than otherwise.[93] A theoretical study indicates that a radial velocity analysis might detect a hypothetical planet of 1.8 M? in Alpha Centauri B's habitable zone.[94]
Radial velocity measurements of Alpha Centauri B made with the High Accuracy Radial Velocity Planet Searcher spectrograph were sufficiently sensitive to detect a 4 M? planet within the habitable zone of the star (i.e. with an orbital period P = 200 days), but no planets were detected.[95]
Current estimates place the probability of finding an Earth-like planet around Alpha Centauri at roughly 75%.[96] The observational thresholds for planet detection in the habitable zones by the radial velocity method are currently (2017) estimated to be about 50 M? for Alpha Centauri A, 8 M? for Alpha Centauri B, and 0.5 M? for Proxima Centauri.[97]
Early computer-generated models of planetary formation predicted the existence of terrestrial planets around both Alpha Centauri A and B,[94][note 5] but most recent numerical investigations have shown that the gravitational pull of the companion star renders the accretion of planets difficult.[92][98] Despite these difficulties, given the similarities to the Sun in spectral types, star type, age and probable stability of the orbits, it has been suggested that this stellar system could hold one of the best possibilities for harbouring extraterrestrial life on a potential planet.[6][93][99][100]
In the Solar System, Jupiter and Saturn were probably crucial in perturbing comets into the inner Solar System, providing the inner planets with a source of water and various other ices.[101] In the Alpha Centauri system, Proxima Centauri may have influenced the planetary disk as the Alpha Centauri system was forming, enriching the area around Alpha Centauri with volatile materials.[102] This would be discounted if, for example, Alpha Centauri B happened to have gas giants orbiting Alpha Centauri A (or vice versa), or if Alpha Centauri A and B themselves were able to perturb comets into each other's inner system as Jupiter and Saturn presumably have done in the Solar System.[101] Such icy bodies probably also reside in Oort clouds of other planetary systems. When they are influenced gravitationally by either the gas giants or disruptions by passing nearby stars, many of these icy bodies then travel star-wards.[101] Such ideas also apply to the close approach of Alpha Centauri or other stars to the Solar System, when, in the distant future, the Oort Cloud might be disrupted enough to increase the number of active comets.[76]
To be in the habitable zone, a planet around Alpha Centauri A would have an orbital radius of between about 1 and so as to have similar planetary temperatures and conditions for liquid water to exist. For the slightly less luminous and cooler Alpha Centauri B, the habitable zone is between about 0.7 and .[103]
With the goal of finding evidence of such planets, both Proxima Centauri and Alpha Centauri AB were among the listed "Tier 1" target stars for NASA's Space Interferometry Mission (SIM). Detecting planets as small as three Earth-masses or smaller within two AU of a "Tier 1" target would have been possible with this new instrument.[104] The SIM mission, however, was cancelled due to financial issues in 2010.[105]
Circumstellar discs
Based on observations between 2007 and 2012, a study found a slight excess of emissions in the 24 µm (mid/far-infrared) band surrounding , which may be interpreted as evidence for a sparse circumstellar disc or dense interplanetary dust.[106] The total mass was estimated to be between 10-7 to 10-6 the mass of the Moon, or 10-100 times the mass of the Solar System's zodiacal cloud.[106] If such a disc existed around both stars, disc would likely be stable to 2.8 AU, and would likely be stable to 2.5 AU.[106] This would put A's disc entirely within the frost line, and a small part of B's outer disc just outside.[106]
View from this system
Looking towards the sky around Orion from Alpha Centauri with Sirius near Betelgeuse, Procyon in Gemini, and the Sun in Cassiopeia generated by Celestia
Simulated night-sky image with a "W" of stars connected by lines and a star labelled "Sol" to the left of the "W"
The sky from Alpha Centauri AB would appear much as it does from the Earth, except that Centaurus would be missing its brightest star. The Sun would appear as a yellow star of apparent magnitude +0.47, roughly the same as the average brightness of Betelgeuse from Earth. It would be at the antipodal point of Alpha Centauri AB's current right ascension and declination, at +60° 50′ (2000), in eastern Cassiopeia, easily outshining all the rest of the stars in the constellation. With the placement of the Sun east of the magnitude 3.4 star Epsilon Cassiopeiae, nearly in front of the Heart Nebula, the "W" line of stars of Cassiopeia would have a "/W" shape.[note 6]
In modern literature, Rigil Kent[107] (also Rigel Kent and variants;[note 7])[19][108] and Toliman,[109] are used as colloquial alternative names of Alpha Centauri (then became the proper name of Alpha Centauri B on 10 August 2018 by approval of IAU).
Rigil Kent is short for Rigil Kentaurus,[110] which is sometimes further abbreviated to Rigil or Rigel, though that is ambiguous with Beta Orionis, which is also called Rigel.
The name Toliman originates with Jacobus Golius' 1669 edition of Al-Farghani's Compendium. Tolimân is Golius' latinisation of the Arabic name ? al-?ulm?n "the ostriches", the name of an asterism of which Alpha Centauri formed the main star.[111][112][113]
During the 19th century, the northern amateur popularist Elijah H. Burritt used the now-obscure name Bungula,[114] possibly coined from "?" and the Latin ungula ("hoof").[19]
Together, Alpha and Beta Centauri form the "Southern Pointers" or "The Pointers", as they point towards the Southern Cross, the asterism of the constellation of Crux.[75]
In Chinese astronomy, Nán Mén, meaning Southern Gate, refers to an asterism consisting of Alpha Centauri and Epsilon Centauri. Consequently, the Chinese name for Alpha Centauri itself is Nán Mén Èr, the Second Star of the Southern Gate.[115]
To the Australian aboriginal Boorong people of northwestern Victoria, Alpha Centauri and Beta Centauri are Bermbermgle,[116] two brothers noted for their courage and destructiveness, who speared and killed Tchingal "The Emu" (the Coalsack Nebula).[117] The form in Wotjobaluk is Bram-bram-bult.[116]
Future exploration
The Very Large Telescope and Alpha Centauri
Alpha Centauri is a likely first target for crewed or robotic interstellar exploration. Using current spacecraft technologies, crossing the distance between the Sun and Alpha Centauri would take several millennia, though the possibility of nuclear pulse propulsion or laser light sail technology, as considered in the Breakthrough Starshot program, could reduce the journey time to decades.[118][119][120] An objective of such a mission would be to make a fly-by of, and possibly photograph, planets that might exist in the system.[121][122] The existence of Proxima Centauri b, announced by the European Southern Observatory (ESO) in August 2016, would be a target for the Starshot program.[121][123]
In January 2017, Breakthrough Initiatives and the ESO entered a collaboration to search for habitable planets in the Alpha Centauri system. The agreement involves Breakthrough Initiatives providing funding for an upgrade to the VISIR (VLT Imager and Spectrometer for mid-Infrared) instrument on ESO's Very Large Telescope (VLT) in Chile. This upgrade will greatly increase the likelihood of planet detection in the system.[124][125]
Distance estimates
Alpha Centauri AB distance estimates
Parallax (mas)
Distance (pc)
Distance (ly)
Distance (Pm)
Henderson (1839) 2.57 ± 0.53 [69]
Henderson (1842) 1.03 ± 0.15 3.34 ± 0.5 [126]
Maclear (1851) 32.4 ± 2.5 [127]
Moesta (1868) [128]
Gill & Elkin (1885) [129]
Roberts (1895) 1.32 ± 0.2 4.29 ± 0.65 [130]
Woolley et al. (1970) [131]
Gliese & Jahreiß (1991) [132]
van Altena et al. (1995) [133]
Perryman et al. (1997) (A and B) [134]
[135][136][137]
Söderhjelm (1999) [138]
van Leeuwen (2007) (A) [139]
van Leeuwen (2007) (B) 37.5 ± 2.5 [140]
RECONS TOP100 (2012) [note 8] [43]
Astronomy portal
Alpha Centauri in fiction
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^ Proxima Centauri is gravitationally bound to the ? Centauri system, but for practical and historical reasons it is described in detail in its own article.
^ [(11.2+35.6)/2]3/79.912=2.0{\displaystyle {\begin{smallmatrix}[(11.2+35.6)/2]^{3}/79.91^{2}=2.0\end{smallmatrix}}} , see formula
^ This is calculated for a fixed latitude by knowing the star's declination (?) using the formulae (90°+ ?). Alpha Centauri's declination is -60° 50?, so the observed latitude where the star is circumpolar will be south of -29° 10'S or 29°. Similarly, the place where Alpha Centauri never rises for northern observers is north of the latitude (90°+ ?) N or +29°N.
^ Proper motions are expressed in smaller angular units than arcsec, being measured in milli-arcsec (mas.) or one-thousandth of an arcsec. Negative values for proper motion in RA indicate the sky motion is from east to west, and in declination north to south.
^ See Lissauer and Quintana in references below.
^ The coordinates of the Sun would be diametrically opposite Alpha Centauri AB, at ?=, ?=+60° 50′ 02.308″
^ Spellings include Rigjl Kentaurus, Hyde T., "Ulugh Beighi Tabulae Stellarum Fixarum", Tabulae Long. ac Lat. Stellarum Fixarum ex Observatione Ulugh Beighi, Oxford, 1665, p. 142., Hyde T., "In Ulugh Beighi Tabulae Stellarum Fixarum Commentarii", op. cit., p. 67., Portuguese Riguel Kentaurus da Silva Oliveira, R., "Crux Australis: o Cruzeiro do Sul" Archived 6 December 2013 at the Wayback Machine, Artigos: Planetario Movel Inflavel AsterDomus.
^ Weighted parallax based on parallaxes from van Altena et al. (1995) and Söderhjelm (1999).
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^ Martin Rees (17 September 2012). Universe: The Definitive Visual Guide. DK Publishing. p. 252. ISBN 978-1-4654-1114-3.
^ James B. Kaler (7 May 2006). The Hundred Greatest Stars. Springer Science & Business Media. p. 15. ISBN 978-0-387-21625-6.
^ Fred Schaaf (31 March 2008). The Brightest Stars: Discovering the Universe through the Sky's Most Brilliant Stars. Wiley. p. 122. Bibcode:2008bsdu.book.....S. ISBN 978-0-470-24917-8.
^ Baily, Francis (1843). "The Catalogues of Ptolemy, Ulugh Beigh, Tycho Brahe, Halley, Hevelius, Deduced from the Best Authorities. With Various Notes and Corrections, and a Preface to Each Catalogue. To Which is Added the Synonym of each Star, in the Catalogues or Flamsteed of Lacaille, as far as the same can be ascertained". Memoirs of the Royal Astronomical Society. 13: 1. Bibcode:1843MmRAS..13....1B.
^ Kunitzsch, P. (1976). "Naturwissenschaft und Philologie: Die arabischen Elemente in der Nomenklatur und Terminologie der Himmelskunde". Die Sterne. 52: 218. Bibcode:1976Stern..52..218K. doi:10.1515/islm.1975.52.2.263. S2CID 162297139.
^ Hermelink, H.; Kunitzsch, Paul (1961). "Reviewed work: Arabische Sternnamen in Europa, Paul Kunitzsch". Journal of the American Oriental Society. 81 (3): 309-312. doi:10.2307/595661. JSTOR 595661.
^ A?mad ibn Mu?ammad al-Farg?n?; Jakob Golius (1669). Muhammedis fil. Ketiri Ferganensis, qui vulgo Alfraganus dicitur, Elementa astronomica, Arabicè & Latinè. Cum notis ad res exoticas sive Orientales, quae in iis occurrunt. Opera Jacobi Golii. apud Johannem Jansonium à Waasberge, & viduam Elizei Weyerstraet. pp. 76-.
^ Elijah Hinsdale Burritt (1850). Atlas: Designed to Illustrate the Geography of the Heavens. F. J. Huntington.
^ (in Chinese) [ AEEA (Activities of Exhibition and Education in Astronomy) ? 2006 ? 6 ? 27 ?]
^ a b Hamacher, Duane W.; Frew, David J. (2010). "An Aboriginal Australian Record of the Great Eruption of Eta Carinae". Journal of Astronomical History & Heritage. 13 (3): 220-234. arXiv:1010.4610. Bibcode:2010JAHH...13..220H.
^ Stanbridge, W. M. (1857). "On the Astronomy and Mythology of the Aboriginies of Victoria". Transactions Philosophical Institute Victoria. 2: 137-140.
^ Overbye, Dennis (12 April 2016). "A Visionary Project Aims for Alpha Centauri, a Star 4.37 Light-Years Away". The New York Times. Retrieved 2016.
^ O'Neill, Ian (8 July 2008). "How Long Would it Take to Travel to the Nearest Star?". Universe Today.
^ Domonoske, Camila (12 April 2016). "Forget Starships: New Proposal Would Use 'Starchips' To Visit Alpha Centauri". NPR. Retrieved 2016.
^ a b "Starshot". Breakthrough Initiatives. Retrieved 2017.
^ Overbye, Dennis (12 April 2016). "Reaching for the Stars, Across 4.37 Light-Years". The New York Times. Retrieved 2017.
^ Chang, Kenneth (24 August 2016). "One Star Over, a Planet That Might Be Another Earth". The New York Times. Retrieved 2017.
^ "VLT to Search for Planets in Alpha Centauri System - ESO Signs Agreement with Breakthrough Initiatives". European Southern Observatory. 9 January 2017. Retrieved 2017.
^ Klesman, Alison (9 January 2017). "ESO and the Breakthrough Initiatives team up to search for extrasolar planets next door". Astronomy Magazine. Retrieved 2017.
^ Henderson, T. (1842). "The Parallax of ? Centauri, deduced from Mr. Maclear's Observations at the Cape of Good Hope, in the Years 1839 and 1840". Memoirs of the Royal Astronomical Society. 12: 370-371. Bibcode:1842MmRAS..12..329H.
^ Maclear, T. (1851). "Determination of the Parallax of ? 1 and ?2 Centauri, from Observations made at the Royal Observatory, Cape of Good Hope, in the Years 1842-3-4 and 1848". Memoirs of the Royal Astronomical Society. 20: 98. Bibcode:1851MmRAS..20...70M.
^ Moesta, C. G. (1868). "Bestimmung der Parallaxe von ? und ? Centauri" [Determining the parallax of ? and ? Centauri]. Astronomische Nachrichten (in German). 71 (8): 117-118. Bibcode:1868AN.....71..113M. doi:10.1002/asna.18680710802.
^ Gill, David; Elkin, W.L. (1885). "Heliometer-Determinations of Stellar Parallax in the Southern Hemisphere". Memoirs of the Royal Astronomical Society. 48: 188. Bibcode:1885MmRAS..48....1G.
^ Roberts, Alex W. (1895). "Parallax of ? Centauri from Meridian Observations 1879-1881". Astronomische Nachrichten. 139 (12): 189-190. Bibcode:1895AN....139..177R. doi:10.1002/asna.18961391202.
^ Woolley, R.; Epps, E. A.; Penston, M. J.; Pocock, S. B. (1970). "Woolley 559". Catalogue of Stars within 25 Parsecs of the Sun. 5: ill. Bibcode:1970ROAn....5.....W. Archived from the original on 8 October 2017. Retrieved 2014.
^ Gliese, W.; Jahreiß, H. (1991). "Gl 559". Preliminary Version of the Third Catalogue of Nearby Stars. Astronomische Rechen-Institut. Retrieved 2014.
^ Van Altena, W. F.; Lee, J. T.; Hoffleit, E. D. (1995). "GCTP 3309". The General Catalogue of Trigonometric Stellar Parallaxes (Fourth ed.). Yale University Observatory. Retrieved 2014.
^ Perryman; et al. (1997). "HIP 71683". The Hipparcos and Tycho Catalogues. Retrieved 2014.
^ Söderhjelm, Staffan (1999). "HIP 71683". Visual binary orbits and masses post Hipparcos. Retrieved 2014.
^ van Leeuwen, Floor (2007). "HIP 71683". Validation of the new Hipparcos reduction.
SIMBAD observational data
Sixth Catalogue of Orbits of Visual Binary Stars U.S.N.O.
The Imperial Star - Alpha Centauri
Alpha Centauri - A Voyage to Alpha Centauri
Immediate History of Alpha Centauri
eSky : Alpha Centauri
Hypothetical planets or exploration
"A Family Portrait of the Alpha Centauri System". SpaceRef.com: 5. 2003. Bibcode:2003eso..pres....5. Retrieved 2003.
Alpha Centauri System
O Sistema Alpha Centauri (Portuguese)
Alpha Centauri - Associação de Astronomia (Portuguese)
Thompson, Andrea (7 March 2008). "Nearest Star System Might Harbor Earth Twin". SPACE.com. Archived from the original on 2 June 2008. Retrieved 2008.
Coordinates: 14h 39m 36.4951s, -60° 50? 02.308?
TANGERINE DREAM - ALPHA CENTAURI - Alpha Centauri
Noisia - Alpha centauri
Alpha Centauri - ESO
Civilization : Alpha Centauri
Hallucinogen - Alpha Centauri
Alpha Centauri CH
Salvatres - Alpha Centauri
Alpha Centauri Meaning
Alpha Centauri - Variieren Naturkonstanten?
Sid Meier's Alpha Centauri
Noisia - Alpha Centauri (HD)
Alpha Centauri.-.009.-.Extrasolare.Planeten.
Traveling to Alpha Centauri?
Alpha_Centauri


text:
Should you give your life over to 'Returnal'?
PlayStation's new exclusive is a 'Metroid'-style, roguelike shmup for the ages.
Jonathan Peltz
I am writing this having just beaten Returnal on my first run. It was an absolute cinch — and when I got to the last boss I thought, "That's it? Do the developers of this game wear diapers? If I wanted something this easy I would have played New Pokémon Snap." I removed the disc, and Returnal'd it from whence it came. Finito.
I'm fucking with you. I just barely escaped from the game's first boss when I started writing this. Returnal is an absolute meat grinder of a game. It adds the appeal of becoming a player's forever game to a stew of inspirational titles like Metroid, Nier: Automata, and Halo. For better or worse, Returnal is meant to be played for the long haul. One to be mastered after it grinds the player's mind and reflexes down to a fine paste, only to rebuild them again stronger and better.
Returnal follows a formula familiar in the roguelike genre: you must pew-pew your way through a third-person action-adventure sci-fi horror, combatting furious be-tentacled monsters that want nothing more to trap you between the business ends of fifty different laser orbs. As it's a roguelike, you have to start your run from the very start in the game when you die, losing all your progress save for a few permanent items and upgrades. Each level — I'm still at the point in the game where I'm seeing the first overgrown, rainy one a lot — consists of a revolving array of procedurally generated rooms and arenas for you to fight and dash around in. To progress, you must find the boss key that unlocks each level's final room.
Returnal is difficult, yes, but its most oppressive demand of the player is one of time. Before the game even begins, it advises the player to use their PS5's standby feature if they want to pause a run, as there is no save function otherwise. Runs of the game's first level have lasted me 30-40 minutes apiece, and of course, that will only keep stretching out as I keep venturing further into the different zones of the planet.
For reference, 30-40 minutes would have you beating the entirety of Hades. That is to say, it's a slow-going affair, and the game floods you with lore, consumable items, permanent items, "malignant" items (that bestow a negative effect to the player along with positive ones), different types of weapon upgrades and chests, and so on and so forth. Though, in one of Returnal's more forgiving overtures to the player, bosses can be skipped after they've been beaten the first time.
The pace accelerates exponentially from the plodding, merciless introductional hours, as Returnal gifts the player with Metroidvania-esque abilities like a sword that can unlock vine-covered rooms and absolutely gank enemies up close, and additional abilities which will essentially make it easier to access more item rooms in the game that were once blocked off, or laser- or water-riddled puzzle areas which cannot be accessed without said special abilities.
When you add a figurine that revives the player on death to the level game's structure, you know shit's about to get real. The game drizzles integral abilities and items into the mix. Beating Returnal's daily challenges also helps to familiarize the player with items and weapons they may not have access to in their single-player-universe, while rewarding them with the game's most valuable permanent resource if conquered. If you want to get a bit of a head start, they're a must.
While these are certainly elements of the genre, I found Returnal particularly opaque and jargon-heavy. I think part of my issue with the overwhelming amount of content is that its items all look so similar to one another. Everything is a facehugger, a pod, an orb, or some sort of hookshot-looking thing. If you're going to properly dive into this one, prepare for it to basically take over your entire gaming life. Even playing just one day apart from my last session, I found myself forgetting crucial information and game rhythms. For example, I'm still not quite sure I know what an "Overload" is. I think it's the game's word for reloading, but I'm not sure.
Everything is a facehugger, a pod, an orb, or some sort of hookshot-looking thing.
The game is also slow to dole out new permanent items and story beats, requiring a bit of patience from the player. Aesthetically, Returnal borrows its first stage almost entirely from the Alien franchise, with the extinct (or perhaps infected) alien race whose environment you're perusing even dubbed "Xenos." There are holograms with recordings of ancient history and titanic statues of exotic creatures or gods.
Mixed in this are hints as to the true mission of the protagonist and memories of her past — which are folding in with the world around her a la Stanislaw Lem's Solaris. The second stage opens up a bit, but then it's just cribbed from the desert-and-tech world of Dune. While the game is a love letter to classic science fiction, and there are meta winks and nods to the protagonist's own love of fantastical stories throughout, I wish it had more — as of seven hours in — of its own identity to stand on.
Thus far, I'm more compelled by spite and wanting to improve and see more of the game than I am by its narrative. In Returnal, you're immediately propelled into sci-fi action upon crash landing on a mysterious alien planet, in a ship that looks almost identical to the one flown by The Mandalorian. I find the protagonist leaden and mercurial to a fault. I'm not sure why every aspect of the story has to be mysterious. We should have something to identify with and ground us.
One of the reasons (yes, I know I keep going back to it) that Hades' narrative progression works so well is that Prince Zagreus is younger than the rest of the Gods in the game, and so we're learning a ton of the world's history along with him. He's open and emotive with the people around him. Returnal is a horror game, sure, but its protagonist is so closed off and inexplicably quiet about the world around her. She has flashbacks that feel more like pieces of a narrative puzzle than anything she is actually experiencing.
On the other side of the spectrum, she is all too willing — especially very early in the game — to jam alien parasites and technology into her body. She's so blasé about it that it's comical. The game also behaves as though being in a time loop itself is some twist it has yet to reveal to the player. By the third death, we know we're in a time loop! Can we move past this plot point?! The Outer Wilds — another recent game where you explore mysterious alien civilizations while stuck in a time loop — has you interacting with colorful characters and learning little vignettes, even if it's not giving you the entire picture.
By the third death, we know we're in a time loop!
While I'm not all-in on the story, the Returnal looks and feels buttery smooth, and it's one of those games where it's just shocking to watch yourself play, in the sense that you think, "Is that really me?" The game is an absolute technical showstopper, with particles flying everywhere and seemingly every motion buoyed by a supporting glow or subtle sound effect or bit of lighting. The lasers just have so much warmth to them.
The game is constantly utilizing the DualSense controller, with rainy sections causing the controller to just sort of purr in your hand, and the speaker unleashing a chunky, synth-y locking sound when your alternate fire reloads. It runs beautifully, and you can transport from one end of a level to another almost instantaneously using the map's teleportation devices (all items in rooms except for currency from defeating enemies remain there as long as you're on the same floor, so you can warp back and forth to pick up stuff you left behind) which results in the character disassembling into molecules and reassembling when traveling. It's a stunning, powerful effect, making clear just how out-of-place you are on this planet.
The tense music by Haxan Cloak's Bobby Krlic will keep your stomach in knots, too. It's at turns moody and quiet, guiding the player through a horrible, yet sedate, environment — then furiously harsh and thumping when the player finds themselves in combat. There's varied instrumentation that I haven't found myself getting tired of yet. It reminded me of the industrial, rhythmic tracks found in Thumper.
One part of the haptic feedback system that I'm certain will be, or is, already polarizing is that your explosive secondary fire is loaded by pressing down on the aiming slightly, while your pitter-patter primary fire is selected by holding down the trigger entirely. There's a distinct kind of partition between the two that the trigger creates. It's unintuitive and you would think it would be reversed, with heavier fire requiring a bigger squeeze, and lighter fire a softer touch. Having said that, I got used to it, and at about an hour in, it became second nature.
The shooting has a beautiful flow to it, feeling completely unique.
The shooting has a beautiful flow to it, feeling completely unique. It reminded me of that tactical-but-mobile flow of playing peak Halo, where you're constantly repositioning yourself and using the environment to group your enemies together. But it could still use some refinement. Returnal offers the player a ton of mobility with its dashing and sprinting — though isn't it a bit immersion-breaking to watch this ostensibly marooned and terrified astronaut zip around like they're Indiana Jones? Unfortunately, I found it vexing to try to deal with any enemies who approached me from behind while I was fighting others. If I use my sword, it covers the screen and seemingly leaves me open to attack from all directions. If I turn around quickly, I might overshoot it with my reticle and just be in complete no-man's-land.
Many of the rooms have a ton of verticality, and the mini-map doesn't do a great job displaying this. There are trenches and plateaus you can use to route your enemies, and, conversely, they can use these to sneak up on you as well. It's particularly frustrating to keep track of teleporting enemies. You can activate a neat real-time-mapping ability that shows you all of the ridges and pockets around you in your room, to help you find nooks and crannies with secret items. It's mesmerizing to watch it work, and it's far more useful than the actual mini-map.
While I'm not in love with the entire package, I'm admittedly completely enraptured by Returnal and compelled to keep fighting through it to the end. Its pulse-pounding combat is mostly smooth and addictive and, having just gotten to the first "Daily Challenge" — a plotless series of rooms with stipulations on how the player can fight enemies, I can see myself getting more strategic and competitive about it all. It's certainly for a specific type of player, and frankly a bit off-putting for anyone short on time or wanting an immediately fulfilling story. It cribs from some of the best experiences of its forebears, and adds the lure of limitless playing time and sky-high skill progression for the player. Once you get sucked in, though, you'll find yourself craving the loop.

redpajama_set_name: RedPajamaCommonCrawl


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GalTime, Contributor
10 Relationship Behaviors You Think Are Odd That Are Totally Normal
08/25/2013 11:49 am ET Updated Oct 23, 2013
By Laura Seldon for GalTime.com
What's "normal" and what's not when it comes to dating, love and relationships? Think you and your partner align with the average couple? Or are your relationship behaviors totally out there? We've asked several therapists, marriage counselors and relationship experts from around the country to shed some light on relationship behaviors that seem odd at first, but are actually quite normal. Take a seat and see how you and your mate compare!
1. Changing Feelings
Once upon a time you loved rocking the highest of high heels. These days, however, you're much more apt to throw on a pair of flats. It may sound simple, but your ever-evolving feelings on shoes can help to serve as a reminder that feelings come and go -- and that's OK.
"Love is a living entity," explains Karen Sherman, Ph.D. "And just like people have good days and bad -- so will there be periods where the lovin' feelings just won't be there. Hang in, focus on the positive, and the feelings will come back."
2. Going Through "Adjustment Periods"
"If you decide to marry, even if you've lived together, the first year is likely to be bumpy," warns Sherman. "You are now in a legally committed relationship, the dynamics change and there is a period of adjustment. Having lived together doesn't prevent this adjustment period."
So, if you and your better half are not in a state of bliss at every moment, if doesn't mean your relationship is doomed -- it just means you're normal.
3. Enjoying Different Hobbies
He's into fantasy football and you're into shopping? Better yet, you're into fantasy football and he's into shopping? Either way, it's totally normal for you and your main squeeze to have different interests.
"You don't have to like all the same things to have a healthy relationship," notes Sherman. "What matters is having the same values." So go ahead and enjoy your fantasy football draft, and then swoon over the new shoes your man just bought online. You both deserve to enjoy your hobbies without feeling guilty.
4. Needing Alone Time
Are you the kind of person who would take yourself out for a date night for one? If so, you are not alone.
"Washing a car, walking a dog or exercising alone are signs of a healthy relationship with a secure attachment," says Lanada Williams, a licensed counselor in Washington DC and Maryland. "Remind yourself, the individual you met still needs time to breathe and thrive."
5. Being Slow to Compliment
When is the last time you told your partner how hot they looked? We're all guilty of holding back compliments, and, according to Licensed Marriage and Family Therapist Holly Cox, it may even be something you're doing on purpose!
"When you give a compliment to anyone, but particularly someone you like a whole lot, you're putting yourself on the line," explains Cox. "Clients tell me they are often afraid their partners will reject the compliment -- or worse, say something along the lines of, 'Wow, you're finally noticing everything I do around here. Uh-huh. What do you want?'"
Although this may be normal behavior, that doesn't mean it's OK. Remember to compliment your partner and accept the praise they give you!
6. Having Trouble Getting in the Mood
Every married couple has experienced one of those nights (or mornings) where one member of the duo is ready for a racy romp, but the other is ready for a mellow nap!
"Virtually all couples have sexual desire problems sooner or later," says Licensed Psychologist Dr. Kate Roberts. "Couples often go long periods of time without having sex and then once they start up again, their sex life continues on its own."
7. Withholding Information
Sure, you told your partner about that expensive purse you just bought -- you just chose not reveal how much you dropped on it!
"Couples often have different priorities for discretionary income and it's not uncommon for them to keep their secret stashes of clothes, toys, candy, or other discretionary items," says Dr. Roberts.
Just remember it's never healthy to lie about how much you spend. If your partner asks how much you blew on that new pair of Jimmy Choos, keep it real. Lying to your partner -- especially about money -- is never going to lead you anywhere good.
8. Sparring, Bickering and Fighting
As two different people with two different philosophies on life, you're bound to disagree at one point or another.
"Fighting is normal," explains Therapist Dana Ward. "While some couples may think fighting is the sign of a bad relationship, it is actually is very important. The key is fighting with a purpose."
So, whether you are fighting about something as trivial as how to fold socks, or as significant as a job transition, make sure to fight the topic -- not each other.
9. Finding Other People Attractive
You may be utterly in love with your partner, but that doesn't mean you can't admire a hottie with a great set of legs.
"You can and should appreciate all the beauty and dashing good looks all around you," shares Ward. However, she notes, "Attractive and attraction is different. Find other people attractive, but stop short of allowing yourself to be attracted to them."
10. Getting Scared and Pulling Away
Pulling away, taking a time out, going on a break -- we're all human, and being vulnerable with someone else can at times be scary enough to make you run for the hills!
"Sometimes when things are getting very serious men, in particular, may pull away while they decided to move forward," explains Relationship Coach Stef Safran.
However, just because one person in the relationship needs a breather, it doesn't mean your relationship is in desperate need of an SOS. It just means you're human!
Now that you've read through these 10 strange relationship behaviors that aren't actually weird at all, hopefully you feel a little better about your own relationship. If you still think you're odd, though, then embrace the quirks that make your relationship special and take a line from Holly Golightly in Breakfast at Tiffany's -- "It may be normal, darling; but I'd rather be natural."
More from GalTime.com:
Does it Matter if You Have a lot in Common?
Absence Shouldn't Make the Heart Grow Fonder
Four Telltale Signs He's NOT the One
5 Things Men Want Women to Know
Laura Seldon is a writer and journalist living in Los Angeles. She has written for Guess Inc., Rock The Vote, and JDate.com and now brings her talents to GalTime. Follow her on Twitter for fun and interesting updates on how to live your best life yet!
Dating Advice Sex Relationships Dating Relationships


FRAMINGHAM, MA – APRIL 1, 2002 – The market for team collaborative applications (TCAs) will require suppliers and customers partner to integrate and customize offerings if TCAs are to play a major role in collaboration over the next several years, according to IDC.
"Team collaborative applications play such a strong supporting role for other business applications that many different types of vendors and customers want TCA on their team," said Mark Levitt, vice president of IDC's Collaborative Computing program. "Ironically, the single largest limiting factor for long-term growth of a distinct horizontal TCA market will be the successful inclusion of native TCA functionality into specific vertical applications, other business applications and operating environments."
IDC's recently published document, Worldwide Team Collaborative Applications Forecast, 2002-2006: Where Will TCAs Play? (IDC #26725) presents a five-year revenue forecast by region and operating environment, and identifies market dynamics and trends of TCA suppliers and customers. Vendor- specific market shares, profiles, and analysis will be published separately next quarter.


A sweeping tale of love's triumph over tragedy and treachery in frontier Australia.
A mistaken identity opens the door for Martin Mulvaney to take his revenge on the granddaughter of his mortal enemy.
An old Scottish feud, a love that should never have happened, and a series of extraordinary coincidences traps two lovers in a family vendetta that threatens to destroy their love, if not their lives.
This entry was posted in Romance Novels and tagged Aussie author, BWL Blurbathon, Frontier Romance, margaret tanner, Savage Possession by margarettanner. Bookmark the permalink.


The California Child Support Automation System project is establishing a pool of qualified business partners to participate in the design, development, conversion and implementation of a single, statewide child support automation system. The project is now initiating a second procurement for services to establish and operate the child support state disbursement unit. The procurement is expected in July.
The project is expected to be worth about $15 million.
California's child support program has been restructured, and the state has to implement a single, statewide automated child support system. The newly created Department of Child Support Services now has responsibility for the program. The state's Franchise Tax Board has responsibility for a statewide automation development project. Two contracts are expected: one for an enforcement system, and a second one for a disbursement unit.
Also in California, an RFP is expected in July for a decision support system for the California Health and Welfare Agency's management information system. The project is estimated at $924,000. The agency is responsible for reducing preventable disease, disability and premature death. It works with various health care provider organizations in the state.


text:
Court Decision on Steroid Case Little Late for Ball Players
Court rules that the government over-stepped it's boundaries.
Published August 27, 2009 • Updated on July 13, 2010 at 1:19 pm
OK, now what?
Reputations are ruined. Clouds of suspicion will always be there. This may be the classic definition of too little, too late for the exposed.
On Wednesday, the 9th U.S. Circuit Court of Appeals ruled that federal agents overstepped their bounds when they seized the list of the 104 Major League Baseball players who tested positive for performance-enhancing drugs in 2003.
Investigators only had a warrant for 10 drug test results as part of the BALCO case, not the 104 results it seized.
Baseball stars including Alex Rodriguez, Manny Ramirez, David Ortiz and Sammy Sosa have all had their names leaked and careers tarnished because they were supposedly on this "sealed" list.
Ortiz was asked to comment on the ruling before his game. "I don't care," he said, never even looking up from his computer.
Other baseball figures had more to say on the topic.
Braves third baseman Chipper Jones: " A lot of people's credibility and a lot of people's dignity have been damaged in this. It's not fair to the clean players. It's not fair to the players who've been leaked. Get 'em all out there so we can start the healing process."
Chicago White Sox manager Ozzie Guillen: "Whoever's got the list, get them out of there, make us suffer for a couple days and move on. Just get the thing out."
Los Angles Dodger manager Joe Torre: " I hate the whole systematic leaking of names, because it's never going to go away. Even though it's something that's six years old, it keeps becoming current news. It's not giving our sport a chance to heal."
St. Louis Cardinal pitcher Adam Wainwright has a different take: " Leak the names that leaked the names. People are obviously breaking the law acquiring those names, and it's not the agreement the federal government had with Major League Baseball."
In 2003, baseball players agreed to drug testing without penalties to determine the extent of use in the sport. If more than 5 percent tested positive, mandatory drug testing would be put in place.
In 2004, federal agents obtained a search warrant and seized the records from the two labs. The court ruled that the government went outside its boundaries.
"This was an obvious case of deliberate overreaching by the government in an effort to seize data as to which it lacked probable cause," Chief Judge Alex Kozinski wrote.
He agrees that the players' union had good reason to want to keep this a secret.
"Some players appear to have suffered this very harm as a result of the government seizure," he said.
So, it seems now that the rest of the players on the list appear to be safe. This ruling should prevent any leaks to the media. Only time will tell, but I think we have been down this road before.


The ME 64k Storage Cell is an item added by Applied Energistics 2. Inserted into an ME Drive or ME Chest it will store ME Network Data. The 64k Storage Cell can hold 520192 items of one item or 266240 items of 63 different items. Using a Cell Workbench allows to pre-format a Cell to store specific items and using an ME IO Port facilitates the transfer of data between the Cell and the Network. The ME Storage Cell is expandable to 4 more increasing sizes of ME Storage from Extra Cells 2, 'Shift+Right-clicking' it while selected will separate the ME Storage Component from the ME Storage Housing.
64k ME Storage Cell has no known uses in crafting.
This page was last modified on 8 August 2016, at 15:51.


Abstract: The EUGS 2016 introduced new challenges and set specific head goals for the policy of the European Union in the fields of external action and security. Such decisions must be implemented and backed by valid intelligence support. The EU intelligence community, that according to this paper is composed by mainly four agencies (EU IntCen, EU IntDiv, SatCen and Europol), represents the backbone for the information and policy making support of the EU governance. In this paper it will be analysed the development of the EU intelligence community in order to prove the existence of a EU intelligence culture, and eventually, the five main elements that emerged in the research, by using the literature on the US intelligence community and its culture as comparation subject. The five main elements taken into account to define the EU intelligence culture and represent the foundation upon which it will be built any future development of the EU intelligence community, that will pass from a European intelligence community to a European Union integrated intelligence system. In a world in constant change in which the EU has to find its own place, the development of its intelligence becomes crucial, to understand and respond to the different types of threats.


2017 has seen casts, creatives, crew and all MTC staff pushed to new and daring heights. MTC ends the year with a new box office record, the largest subscriber base of any theatre company in the country and an abundance of artistic triumphs at home and abroad. As we look back on 2017, here are some of our favourite memories on and off stage.
Welcome to the 1940s, where glamour and prosperity mask the dark side of politics in Washington DC. Our first show of 2017, Born Yesterday, presented mid-century America in all its lavish, post-war glory. An economic boom can be seen most plainly in the dresses of the day, beautifully designed by Set & Costume Designer Dale Ferguson.
Johnny Carr, Ursula Mills and Helen Morse discussed Annie Baker's mesmerising and intimate new play, John, which was one of Time Out's Top 10 shows in Melbourne this year.
Truth, like drama, is subjective. Master playwright and Irish literary hero Brian Friel explores this concept in his imaginary town Ballybeg; a setting that spans two centuries and holds the secrets of his most lauded characters.
In the final scene of Joanna Murray-Smith's acerbic comedy Three Little Words, a treasured family heirloom smashed spectacularly on stage – the Tantalus. We had a look at how you smash a priceless possesion on stage every night.
Kate Atkinson smashes Tantalus in Three Little Words.
Set & Costume Designer Mel Page returned from Oslo, Norway to reunite with her long-time collaborators Lally Katz and Anne-Louise Sarks on the production of Minnie & Liraz. When director Anne-Louise approached Mel to design the set and costumes of Lally's new play, she knew it was an opportunity that was hard to resist.
Looking at Mel Page's jackets behind-the-scenes at MTC HQ Wardrobe.
MTC's 2017 education show Melbourne Talam wrapped a seven-stop regional tour, completing their 31st show at Launceston College in Tasmania. Community Outreach Manager Karin Farrell told us the ins and outs of theatre on the road.
on Melbourne Talam's regional tour.
In Macbeth, the witches instigate the downfall of Shakespeare's greatest tyrant. Shareena Clanton, Kamil Ellis and Jane Montgomery Griffiths tell us about their experiences embodying the three 'weird sisters' in SImon Phillips' production.
'In all my years working in live performance, there are few – if any – productions that have matched the pure joy audiences get from watching Noises Off.' – Brett Sheehy on Noises Off.
The cast of Noises Off on stage.
Hold onto your wig. MTC wig maker Jurga Celikiene has been raising-hairs with her specialty wigs for 10 years. Here, Jurga shows us her process of wig making.
Jurga Celikiene shows us how to make a wig.
In centre place (because she demands it) of Noël Coward's comedy of manners Hay Fever, is the illustrious, revered, grande dame Judith Bliss. Humble and charming is the actor who portrayed her in MTC's production – Australian stage legend Marina Prior.
Marina Prior discusses playing one of the most 'delicious' characters of theatre, Judith Bliss.
Theatre luminary John Bell spoke about his love of Shakespeare, his role in Australia's new wave theatre movement, and his performance in a powerful, funny and deeply moving play, The Father.


text:
Q: print pearson correlation residual values I am able calculate pearson correlation between two list:
import scipy
from scipy import stats
from scipy.stats import pearsonr
List1 = [1,2,3,4,5]
List2 = [2,3,4,5,6]
pearson = scipy.stats.pearsonr(List1,List2)
print "pearson correlation: " + str(pearson)

I would like a list of the observed - expected values for list1. Would someone know how to extend this code to print the observed-expected values please?
Given the instructions for this test:
http://docs.scipy.org/doc/scipy-0.14.0/reference/generated/scipy.stats.pearsonr.html
I'm not sure that I can obtain these values using this method, or if something else is more suited?
Edit, I can now calculate the linear regression model:
import sys
import scipy
from scipy import stats

List1 = [1,2,3,4,5]
List2 = [1,3,5,6,7]

slope, intercept, r_value, p_value, std_err = stats.linregress(List1,List2)

Added note:
I assumed that once I fitted a model as kindly suggested, that I would figure out how to fit the residuals using the linregress package.
However, when I call:
>>> dir(stats.linregress)
['__call__', '__class__', '__closure__', '__code__', '__defaults__', '__delattr__', '__dict__', '__doc__', '__format__', '__get__', '__getattribute__', '__globals__', '__hash__', '__init__', '__module__', '__name__', '__new__', '__reduce__', '__reduce_ex__', '__repr__', '__setattr__', '__sizeof__', '__str__', '__subclasshook__', 'func_closure', 'func_code', 'func_defaults', 'func_dict', 'func_doc', 'func_globals', 'func_name']

I can see that there's nothing there that would resemble .resid/.residuals etc.Could someone point me in the right direction for the next step? The aim is to calculate a list of the observed - expected values for list1 (see above?)
Correction:
import scipy
from scipy import stats
x = [28,26,44,40,10,7,27,25,26,10]
y = [0.055,0.074,0.049,0.067,0.037,0.036,0.044,0.041,0.071,0.03]
print scipy.stats.linregress(x,y)

Gives me this:
(0.00075454346398073121, 0.032064593825268217, 0.59378410770471368, 0.07031502216706445, 0.00036149633561360087)

which i assume is the residuals. Many thanks.
*******CORRECTION******
0.00075454346398073121 is the slope (m), and  0.032064593825268217 is constant (c).
To obtain the raw residuals for the first two items in lists x and y (see above) respectively, use y=mx+c:

list1 = [28,26]
X1 observed = 28; X1 predicted = 0.000754*28 + 0.03206 = 0.0531
X1 residual = 28 - 0.0531 = 27.94

X2 observed = 26; X2 predicted = 0.000764*26+0.03206 = 0.051664
X2 residual = 26 - 0.051664 = 25.94

list2 [0.055,0.074]
Y1 observed = 0.055; Y1 predicted = 0.000764*0.055+0.03206 = 0.032
Y1 residual = 0.055 - 0.032 = 0.022

Y2 observed = 0.074; Y2 predicted = 0.000764*0.074+0.03206 = 0.032
Y2 residual = 0.074 - 0.032 = 0.041.

Many thanks.

A: It returns a tuple, which you can unpack:
corcoef, pval = scipy.stats.pearsonr(List1,List2)

What you are after is a linear regression: http://docs.scipy.org/doc/scipy-0.14.0/reference/generated/scipy.stats.linregress.html#scipy.stats.linregress
You can then use the model to calculate the residuals.

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text:
Captain Thakur has sights firmly set on Asian Games title
Tamil Thalaivas' Ajay Thakur has had a charmed tenure as the Indian Kabaddi team captain. He led India to victory in Asian Kabaddi Championship and then followed it up with a successful campaign at the recent Kabaddi Masters Dubai 2018. Now he is set to take the reins once again in the upcoming Asian Games and he could not be more thrilled.
"I am very happy to captain a team like India," he said ahead of the games, "In fact, I am happier with my team's performance than my own. I want that we should win all the matches where I am the captain. The team has shown its class in recent events like Kabaddi masters Dubai 2018."
Being the team man that he is, Thakur shies away when asked about his own impressive performances of late, including in the Dubai campaign where he scored two match winning Super 10s.
"Since I have become the captain, I don't take my individual performance into account anymore," he said, "My focus is on the team. I would rather that the team does well instead of me performing extraordinarily as an individual."
Leading a team full or superstars like India, though, does come with its own set of challenges. With each player having sky high expectations from themselves keeping a clam head becomes extremely important. Thakur says his manta while dealing with the team is clear, let go of the past and always keep moving forward.
"I tell everyone that even if we make a mistake during the match we will try to overcome it together instead of dwelling on it for too long. I tell them to let it go. We can't change what has happened, what matters is how we can do better from there. We have to take into account what best we can do in the rest of the match and the matches to come. Leaving the past behind is important," stressed Thakur.
Satisfied with the performance on the field, he had a message for those who are the eighth player off the field; the fans.
"I want to tell the fans to keep up their support. We got a lot of love and support from our fans in the recent Kabaddi Masters Dubai 2018 event. I keep reading the fans' comments and messages whenever I can. We are constantly trying to better our game and I wish the fans continue their support for the sport and for us," Thakur said before signing off with a smile.
Visit https://www.raidforgold.in/ to pledge your support for the Indian Kabaddi team in the upcoming Asian Games.
Tamil ThalaivasAjay ThakurPro Kabaddi League Season 6, 2018NewsEnglish


text:
Lucy Citti Ferreira (São Paulo, 11 de Maio de 1911 --- Paris, 17 de novembro de 2008) foi uma pintora e desenhista brasileira.

Em 1930, em Havre (França), iniciou-se na pintura, estudando com André Chapuy, na Escola de Belas Artes do Havre, onde obtém importantes prêmios. Entre 1932 e 1934, em Paris, aperfeiçoou-se em pintura com Armand Matial na Escola de Belas Artes de Paris.

Participou do Salão de Maio, em suas três versões, acontecidas em São Paulo nos anos de 1937, 1938 e 1939.

De 1935 a 1946, em São Paulo, estudou pintura com Lasar Segall, sendo sua modelo de pintura.

Em 1949, em Paris, casou-se com o pianista e compositor russo Georges Alexandrovitch.

Pintores de São Paulo (estado)
Naturais da cidade de São Paulo
Mortos em 2008

redpajama_set_name: RedPajamaWikipedia