Asteroids

Circular features and pits on Ultima Thule

NASA and The Johns Hopkins University Applied Physics Laboratory have published some photos of the Kuiper belt object cataloged as 2014 MU69 and nicknamed Ultima Thule taken by the New Horizons space probe’s LORRI camera only six minutes before its maximum approach. At only 6,628 kilometers (4,109 miles) from it and at its very high speed there was the risk of not being able to perfectly aim at a such a small object but the operation was successful.

The L08-E1 area on asteroid Ryugu touched by Hayabusa 2 (Image courtesy JAXA)

A few hours ago, the Japanese space probe Hayabusa 2 touched down on the soil of asteroid Ryugu to collect some samples of regolith, the soil’s surface layer, which will be transported back to Earth. This is the first of the three possible attempts and now the Japanese space agency JAXA will have to assess whether to look for another area on the asteroid and proceed with a second attempt.

Ultima Thule has a shape even stranger than expected

NASA and the Johns Hopkins University Applied Physics Laboratory have published new images of the Kuiper belt Object cataloged as 2014 MU69 and nicknamed Ultima Thule along with animations that show new details of its shape. A sequence of 14 images captured by the New Horizons space probe during its January 1, 2019 flyby shows that the this object’s two lobes are not vaguely spherical as it seemed but in particular the larger one is definitely flat, to the point that it was compared to a pancake, and it’s not clear why it has that shape.

Artist’s impression of a planetesimal (Image courtesy Ko Arimatsu / NAOJ. All rights reserved)

An article published in the journal “Nature Astronomy” reports the discovery of a planetesimal, which is an object of the type that probably formed planets, dwarf planets and asteroids, with an estimated radius of about 1.3 kilometers in the Kuiper Belt. A team led by Ko Arimatsu of the National Astronomical Observatory of Japan (NAOJ) used two 28 cm amateur telescopes using the occultation technique in a 60-hour monitoring. The analysis of the data revealed what appears to be a planetesimal whose presence has long been predicted by the models of planetary formation but had never been identified.

Some details on the geology of Ultima Thule

The Johns Hopkins University Applied Physics Laboratory, which collaborates with NASA at the New Horizons mission, has published a new image of the Kuiper Belt Object cataloged as 2014 MU69 and nicknamed Ultima Thule which offers more details of its geological features. Various pits, the great depression on the smallest lobe, the “collar” that joins the two lobes, clear and dark features will be studied to get answers to the many questions posed after receiving the first images taken by the space probe in its New Year’s Day 2019 flyby.