In Our Skies: 2018’s top 10 list of astronomy and space events
The 2018 has now passed into the history books.
Several luminaries from the fields of astronomy and space left us during this past year, including Apollo moonwalking astronauts Alan Bean (Apollo 12) and John Young (Apollo 16), renowned British astrophysicist Stephen Hawking, and Comet Hale-Bopp co-discoverer Thomas Bopp.
Meanwhile, it is time once again for this author’s quasi-objective look at the top 10 astronomy and space events of the past year.
Dates in parentheses indicate the editions of this feature in which the topic in question was discussed.
Drumroll, please . . .
10.) Exploration of the inner solar system continues with the launch of the BepiColombo mission – a joint mission between the European Space Agency (ESA) and the Japan Aerospace Exploration Agency (JAXA) involving two separate spacecrafts – on Oct. 19, 2018. After gravity-assist flybys of Earth and Venus and six flybys of Mercury, BepiColombo will enter into orbit around Mercury in late 2025. (Oct. 26, 2018)
9.) In October 2008 a very tiny asteroid designated as 2008 TC3 impacted the atmosphere and exploded, raining down fragments (now collectively known as the Almahata Sitta meteorite) onto the Nubian Desert in Sudan. Amino acids – among the building blocks of life – have been found in these fragments, as well as small structures called nanodiamonds. An analysis of these structures published in early 2018 indicates that 2008 TC3 came from near the core of a Mars-sized world that no longer exists, but which instead was destroyed by violent collisions in our solar system’s early history. (April 20, 2018)
8.) As is true every year, numerous small bodies of our solar system passed close by Earth in 2018, many of these being discovered by the ongoing survey programs. Perhaps the highlight of the year was Comet Wirtanen, which became an easy naked-eye object when it passed 7 million miles from Earth in mid-December. (April 13, 2018, Dec. 7, 2018 and Dec. 14, 2018)
7.) Exploration of the outer solar system continues as well, with the announcement in December of the discovery of the most distant object in the solar system yet found: 2018 VG18, over three times Pluto’s average distance from the sun. The New Horizons spacecraft encountered the distant small world nicknamed Ultima Thule this past New Year’s Day, and meanwhile back in November the Voyager 2 spacecraft, launched in 1977, left the solar system and entered interstellar space. (June 22, 2018 and Dec. 28, 2018)
6.) The Kepler mission, which discovered over 2,700 planets beyond our solar system since its launch in 2009 (and a similar number of candidate worlds waiting to be confirmed) came to its end in late October when the spacecraft ran out of fuel. But all is not lost, since the Transiting Exoplanet Survey Satellite (TESS) mission, launched on April 18, 2018, will continue and expand Kepler’s mission. Meanwhile, among the many planet discoveries announced in 2018 was a super-Earth orbiting the nearby star 40 Eridani, the parent sun of the fictional planet Vulcan from Star Trek, although this world is too large and too close to its sun to be habitable. (April 27, 2018, Nov. 9, 2018 and Nov. 16, 2018)
5.) One of the biggest stories from 2017 was the first detection of gravitational waves, disturbances in the fabric of space-time predicted by Albert Einstein’s Theory of General Relativity and caused by extremely energetic events like the mergers of black holes. Several more detections have been made since then, with the current total being 11; among these is the most powerful such merger ever recorded. (April 6, 2018)
4.) In late July Mars came the closest to Earth that it has in the past 15 years, although studies of its surface from Earth were hampered by an unusually strong Martian dust storm. The on-site study of Mars continues with various space missions both in Mars orbit and on the Martian surface, with one examination finding the apparent source of these dust storms: a series of dusty plains along Mars’ Equator. Meanwhile, NASA’s Mars InSight mission touched down on the Martian surface on Nov. 26, 2018 to begin a geophysical examination of the surface environment as well as underground. (Aug. 24, 2018 and Nov. 30, 2018)
3.) Two small near-Earth asteroids were visited by spacecraft in 2018: Ryugu by JAXA’s Hayabusa2 mission (which arrived in late June) and Bennu by NASA’s OSIRIS-REx mission (which arrived in December). Both missions are expected to return samples of their respective destination asteroids back to Earth during the early 2020s. (June 22, 2018, Oct. 19, 2018 and Dec. 14, 2018)
2.) The first heavy-lift rocket to be launched in three decades lifted off on February 6, with the dramatic and successful launch of Space Exploration Technologies’ (SpaceX) Falcon Heavy rocket from Kennedy Space Center, Florida. The Falcon Heavy launch featured the deployment of SpaceX founder Elon Musk’s Tesla Roadster sports car into solar orbit and the spectacular simultaneous touchdown of the two reusable first-stage booster rockets. After further successful testing we will once again have the capability of lifting humans and large payloads beyond Earth orbit. (Feb. 2, 2018)
1.) Exploration of the very inner solar system has commenced with the launch of the Parker Solar Probe on August 12. In early November Parker approached to 15.4 million miles of the sun – the closest any spacecraft has ever approached to our parent star – and after gravity-assist flybys of Venus will be approaching the sun as closely as 4.3 million miles by the mid-2020s, in the process providing us unprecedented information about the star that gives us life. (Aug. 17, 2018)
And now, onward into 2019, and into whatever new discoveries and adventures await us . . .
Alan Hale is a professional astronomer who resides in Cloudcroft. Hale is involved in various space-related research and educational activities throughout New Mexico and elsewhere.