CLEVELAND - Her name is Juno. She is a small, faint asteroid that will be coming into view this weekend. With a little luck and a little equipment, you just might get a glimpse of this space rock.
This week, Juno will arrive at a point opposite the sun, in what astronomers call "opposition." But since the asteroid will be only magnitude 9.8, conditions are not favorable. At its brightest, Juno is only magnitude 7.4, which is much too faint to be visible with the unaided eye.
Grab your telescope and look in the southern sky. You'll see the brightest star, Arcturus, standing out right away. Just down and to the left should be Juno. (See image above).
"At magnitude 9.8, Juno will be a challenging object to see using binoculars, but should be easily visible in most telescopes, provided viewing conditions are good. However, because of its tiny size, it will look like a star-like point of light in even the largest telescopes," according to Space.com .
"If Juno looks just like a star, how will you know if you've seen it? Make a sketch of the field and check again the next night or even the next hour. Juno will have moved detectably. This is exactly the way that astronomers detect new asteroids and comets: by their movement."
On Sunday night (May 20), Juno will be nicely framed by two fairly bright stars, Yed Prior in Ophiuchus and Mu Serpentis in the western part of the only two-part constellation, Serpens.
Ophiuchus was in the news recently when some astrologers decided to add it to the 12 zodiac constellations. Astronomers found this amusing because they had recognized Ophiuchus as a large and important constellation for thousands of years. In fact, the sun, moon, and planets spend far more time in Ophiuchus than they do in Scorpius next door.
Ophiuchus is known as "the serpent bearer" also called Asclepius in roman mythology, the father of medicine. Early physicians used snake venom in some of their treatments, so Asclepius is depicted holding a severed snake: head in one hand, tail in the other.
These two halves of Serpens are known as Serpens Caput and Serpens Cauda. Juno is located between Mu, the southernmost star in Serpens Caput, and Yed Prior (Delta Ophiuchi), the westernmost star in Ophiuchus.
Be sure to also take a look at Venus, which should appear low in the northwest just after sunset. Venus is dropping rapidly towards the sun, heading for its transit on June 5 and 6. Even in modest binoculars you can clearly see Venus as a tiny crescent, backlit by the sun. (h/t Space.com )