Reported from the Institute for Astronomy, University of Hawaii,
We often think of asteroids and comets as distinct types of small bodies, but astronomers have discovered an increasing number of "crossovers." These objects initially appear to be asteroids, and later develop activity, such as tails, that are typical of comets.
Now, the University of Hawaiʻi 's Asteroid Terrestrial-impact Last Alert System (ATLAS) has discovered the first known Jupiter Trojan asteroid to have sprouted a comet-like tail. ATLAS is a NASA-funded project using wide-field telescopes to rapidly scan the sky for asteroids that might pose an impact threat to Earth. But by searching most of the sky every two nights, ATLAS often finds other kinds of objects – objects that aren't dangerous, but are very interesting.
Early in June 2019, ATLAS reported what seemed to be a faint asteroid near the orbit of Jupiter. The Minor Planet Center designated the new discovery as 2019 LD2. Inspection of ATLAS images taken on June 10 by collaborators Alan Fitzsimmons and David Young at Queen's University Belfast revealed its probable cometary nature. Follow-up observations by UH astronomer J.D. Armstrong and his student Sidney Moss on June 11 and 13 using the Las Cumbres Observatory global telescope network confirmed the cometary nature of this body.
Later, in July 2019, new ATLAS images caught 2019 LD2 again – now truly looking like a comet, with a faint tail made of dust or gas. The asteroid passed behind the Sun and was not observable from the Earth in late 2019 and early 2020, but upon its reappearance in the night sky in April of 2020, routine ATLAS observations confirmed that it still looks like a comet. These observations showed that 2019 LD2 has probably been continuously active for almost a year.
(Score: 5, Informative) by takyon on Friday May 22 2020, @02:56AM
This sounds like good bait for that AC(s) that got mad at the way asteroids and comets are characterized, and the Philae lander bouncing off of comet 67P/Churyumov–Gerasimenko.
The Jupiter trojan population is ripe for study, and hopefully we will see pictures of some starting in 2025 [wikipedia.org], with the large binary trojan 617 Patroclus [wikipedia.org] being visited in 2033. Unrelated: We may get a flyby of Pallas [wikipedia.org] as a secondary payload of the Psyche mission. No love for Hygiea though.
[SIG] 10/28/2017: Soylent Upgrade v14 [soylentnews.org]
(Score: 2) by c0lo on Friday May 22 2020, @03:33AM
After the [Continue], with my emphasis
For reference [poetryfoundation.org]:
https://www.youtube.com/watch?v=aoFiw2jMy-0 https://soylentnews.org/~MichaelDavidCrawford
(Score: 1, Offtopic) by Anonymous Coward on Friday May 22 2020, @03:52AM (4 children)
Before it hits the atmo, with the force greater than humanities entire Nuclear arsenal, where the hell is DeathMonkey's lost journal? Athanasius Kircher is rolling in his dormant account! This only demonstrates what the Mad Kind was trying to say, that per capita, there are many different capitas to be per, and America has the best Capitas, like fifty of them, and Puerto Rico and Guam, and the District of Swampiness. So where is DeathMonkey's lost journal? If we do not hear from DeathMonkey, or an explanation from admin, within 24 hours, we will being "Operation Misnamed Soylent-killer Asteroid". The clock has begun.
(Score: 2, Offtopic) by aristarchus on Friday May 22 2020, @04:43AM (3 children)
AC is not wrong. I received this message:
And no such DeathMonkey journal entry was forthcoming. Failure to press save, as with the dotardly Anthananius Kirchner? Or Admin intervention, under the direction of their Russian paymasters under the guidance of their Brit (Philby?) emeritias Chief Editor, the Janiragnorak? How could we ever, possibly, know, being mere Soylentils, refugees from a greater evil, and now delivered into a petty evil. Give us our DeathMonkey!!!
Oh, and #Freearisarchus!!! He has been so patient with all you rightwing idiots.
(Score: 3, Informative) by DeathMonkey on Friday May 22 2020, @05:29PM (2 children)
I decided against giving that dopey conspiracy theory any more oxygen...
So I deleted it right after I hit save.
(Score: 2, Insightful) by aristarchus on Friday May 22 2020, @08:38PM (1 child)
Probably the right choice. Khallow in particular seems to be triggered by this.
(Score: -1, Redundant) by Anonymous Coward on Friday May 22 2020, @08:58PM
Says the whiner.
(Score: 3, Insightful) by aristarchus on Friday May 22 2020, @05:07AM (1 child)
The asteroids disrupted by the planet Jupiter, who is Zeus in Greek, and who backed the Trojans in the war immortalized in Homer's Iliad, are called Trojans. Perhaps their perturbation is not an accident, and is the cosmic retribution for the crimes of Mycenaean Greeks? But in any case, it is a good idea to have a broad field constant scope like ATLAS holding up the sky for us.
(Score: 0) by Anonymous Coward on Friday May 22 2020, @03:10PM
I prefer from History of the World Part One: "I'm looking for a pack of Trojans!"
(Score: 2) by StupendousMan on Friday May 22 2020, @02:53PM (2 children)
Asteroids which have orbits loosely locked to that of Jupiter -- so that they share its orbit, but in locations which are 60 degrees ahead or behind the planet -- are called "Trojan asteroids". There's a smaller group which sits nearly opposite to Jupiter in its orbit, which are called "Hildas".
This asteroid's orbit indicates that it recently made a close pass to Jupiter, so that its original orbit has been modified. This new orbit does NOT place it in either the Trojan or Hilda families. You can see for yourself at Tony Dunn's orbital simulator site:
https://twitter.com/tony873004/status/1263653962999197696 [twitter.com]
I have no idea why the news stories have made this mistake.
(Score: 0) by Anonymous Coward on Friday May 22 2020, @02:59PM
I have no idea why orbital simulators are run on Twitter!
(Score: 2) by takyon on Friday May 22 2020, @06:44PM
https://en.wikipedia.org/wiki/2019_LD2 [wikipedia.org]
https://www.minorplanetcenter.net/db_search/show_object?object_id=2019+LD2 [minorplanetcenter.net]
https://ssd.jpl.nasa.gov/sbdb.cgi?sstr=3842810 [nasa.gov]
Wikipedia, the IAU's Minor Planet Center, and JPL are calling it a Jupiter trojan.
[SIG] 10/28/2017: Soylent Upgrade v14 [soylentnews.org]