[meteorite-list] Dark Lava Floor of Crater Billy Seen By SMART-1
From: Ron Baalke <baalke_at_meteoritecentral.com>
Date: Tue Feb 21 11:33:55 2006
Dark lava floor of crater Billy seen by SMART-1
European Space Agency
16 February 2006
This composite image, taken by the Advanced Moon Imaging Experiment
(AMIE) on board ESA's SMART-1 spacecraft, shows crater Billy at the edge
of a large lava plain on the Moon.
The AMIE camera obtained two images in consecutive orbits, from a
distance of about 1260 kilometres with a ground resolution of
approximately 114 metres per pixel. Each image has a field of view of 56
Crater Billy is located on the southern fringes of the Oceanus
Procellarum, on the western half of the Moon's Earth-facing side (50?
West, 13.5? South). It lies to the south-east of the similar-sized
crater Hansteen and west-south-west of the lava-flooded crater Letronne.
The Oceanus Procellarum's southern area is low on spectacle but high in
terms of geological interest. An irregular bay, the Mare Humorum on the
edge of the "ocean" can be seen below and to the east of the craters
Billy and Hansteen.
Billy is an old impact crater, 46 kilometres in diameter, with a rim
rising to 1300 metres above its flat floor. The floor of Billy has been
flooded by basaltic lava with a low albedo, meaning it leaves a dark
Billy's floor is one of the darkest spots on the Moon's face, and can
easily be seen any time when it is illuminated, even at full Moon. Billy
contrasts with Hansteen, which is light-coloured with a hummocky floor.
Billy is named after the French Jesuit astronomer Jacques de Billy
(1602-79), who was one of the first to reject the role of astrology in
science, along with superstitious notions about the malevolent influence
For more information:
Jean-Luc Josset, SPACE-X Space Exploration Institute
E-mail: jean-luc.josset _at_ space-x.ch
Bernard H. Foing, ESA SMART-1 Project Scientist
E-mail: bernard.foing _at_ esa.int
Received on Tue 21 Feb 2006 11:13:04 AM PST