All About Ultima: New Horizons Flyby Target is Unlike Anything Explored in SpaceDecember 26, 2018
(...) From its brightness and size, New Horizons team members have calculated Ultima's reflectivity, which is only about 10 percent, or about as dark as garden dirt. Beyond that, nothing else is known about it — basic facts like its rotational period and whether or not it has moons are unknown.
"All that is about to dramatically change on New Year's Eve and New Year's Day," said New Horizons Principal Investigator Alan Stern, also of SwRI. "New Horizons will map Ultima, map its surface composition, determine how many moons it has and find out if it has rings or even an atmosphere. It will make other studies, too, such as measuring Ultima's temperature and perhaps even its mass. In the space of one 72-hour period, Ultima will be transformed from a pinpoint of light — a dot in the distance — to a fully explored world. It should be breathtaking!"
"New Horizons is performing observations at the frontier of planetary science," said Project Scientist Hal Weaver, of the Johns Hopkins University Applied Physics Laboratory in Laurel, Maryland, "and the entire team looks forward to unveiling the most distant and pristine object ever explored during a spacecraft flyby."
"From Ultima's orbit, we know that it is the most primordial object ever explored. I'm excited to see the surface features of this small world, particularly the craters on the surface," said Deputy Project Scientist Cathy Olkin, of SwRI. "Young craters could provide a window to see the composition of the subsurface of Ultima. Also by counting the number and impactors that have hit Ultima, we can learn about the number of small objects in the outer solar system." (...)
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