Friday, July 29, 2011
Lost in the reporting about the Space Shuttle retirement the Dawn mission went under reported. The Dawn spacecraft is investigating the two largest asteroids in the Solar System. Vesta and Ceres. Last week it went into orbit around Vesta. NASA is holding a press conference on August 1 to explain the findings in detail.
These two asteroids have a special place in my heart as they were the setting for my book THE SETTING EARTH which is free to download this weekend.
The real work of the Dawn Spacecraft won't begin until she settles into orbit and can start taking readings, but she has already discovered some mysteries.
Vesta is one of the shiniest objects in the Solar System. It was thought that its shininess was because it is primarily composed of Iron-Nickel, a very tough metal. However the impact craters on its surface are much shallower than one would expect if is was all Iron-Nickel, so there is something about its surface composition that we don't know that makes the impacts shallower than predicted.
It also has some huge grooves that go completely around the proto-planet. We can speculate how those were formed but until we get more information that speculation is pretty meaningless. Some of the smaller grooves were expected. Those little lines are most likely formed as giant boulders shook loose and started rolling across the surface. In the very low gravity they continue to roll for quite a long time.
Over the coming months Dawn will make more and more discoveries. As she settles into orbit we will be able to determine the exact mass and density of Vesta. We will get a much better look at her surface and find out what caused these mysterious features.
One thing I do expect from the Dawn Mission is the unexpected. Whenever we explore new worlds we always find things that fill us with awe. The Voyager probes revealed that Jupiter has a system of moons that are worlds in their own right with liquid oceans under the ice that not only will make them good places for colonization but might harbor life of their own.
Revisiting the Earth's Moon we discovered that the Apollo Missions landed on the driest parts of the lunar surface. That probably wasn't a coincidence, safety engineers like to have people land on the flattest, most boring surfaces just because landing in craters and on the sides of mountains increases the dangers exponentially.
Dawn is the first spacecraft to orbit a large asteroid and she sure to make some amazing discoveries. Soon Vesta will show herself to be a unique world with strange properties that no one imagined. As we learn about these we can figure out uses for this new world and that will lead to a fantastic future.
By Darrell B. Nelson author of I KILLED THE MAN THAT WASN'T THERE