Hubble: A Lunar Prospecting Machine
When we were there:
Apollo 17 panorama
America has always been a land of pioneers. Europeans settled in this country more than 300 years ago to build new homes and new lives. In the mid-1800s, about 250,000 Americans answered the call to move west.
They packed a few possessions in wagons and traveled thousands of miles across the country. Like their ancestors who settled this country, the pioneers used the resources they found around their new homes to build houses, plant crops, and search for water.
Now, 150 years later, the U.S. is considering another pioneering journey,
this time to the Moon and beyond. Future residents of the Moon,
however, will find it even harder to be pioneers. The Moon
does not provide the most essential resource needed for life — an
Like the pioneers who settled the American west, astronauts
will have to rely on their new surroundings to supply needed
resources — in this case, oxygen.
Scientists know how to make oxygen gas from certain minerals,
such as titanium oxides. They also know these
minerals can be found on the Moon because they are present
in some of the rocks and soils that Apollo astronauts brought
back to Earth in the 1970s. The question NASA scientists are trying to
answer is: Are there other sites on the Moon that also contain these minerals?
Hubble's hunt for resources
shots: Sites studied
NASA used the Hubble Space Telescope to answer this question. The telescope looked at ultraviolet light reflected off the Moon's surface. Ultraviolet light reflected off titanium oxide minerals looks different from that of other minerals.
on the Moon
Hubble viewed the ultraviolet glow from minerals at two Apollo landing
sites, where astronauts landed more than 30 years ago. Then the telescope
observed another site where astronauts did not land: the young Aristarchus impact crater and
the adjacent Schroter's Valley rille. The ultraviolet
light from that site looks somewhat like the light taken from the Apollo
landing sites, indicating that Aristarchus and Schroter's Valley could
contain some of the titanium oxides that future Moon pioneers will need
to produce oxygen.
This observation marks the first time that Hubble has assisted in human space exploration. Scientists normally use the telescope to study more distant objects such as other galaxies and dying stars.
Looking at the Moon is not an easy task for Hubble. The Moon moves across the sky very quickly, making it difficult for Hubble to follow its path. So why was Hubble used?
Staying above it all
Above the air,
Hubble sees well
The answer has two parts: First, the Earth's atmosphere absorbs some ultraviolet light, so not all of the light reaches the ground. A telescope in space, like Hubble, is above the atmosphere and can collect the ultraviolet light.
Second, the Moon is so dim in ultraviolet light that it took sensitive instruments like Hubble's to see it. Even so, Hubble had to look for a long time to collect enough light to make the images.