New Moon Probe Raises Questions About What to Do Next in Space
The last moon mission on NASA’s
current schedule — a small, unmanned
spacecraft that will study moon dust
and the lunar atmosphere — is
scheduled to launch on Friday from
Wallops Island, Va., elating scientists
who study the moon but highlighting
political questions about what NASA
should do next.
The Smart Car-size spacecraft, which
NASA calls the Lunar Atmosphere and
Dust Environment Explorer , will take
30 days to get into orbit around the
moon, spend the next 30 days checking
its equipment and proceed with
scientific work for 100 days, searching
for water molecules in the atmosphere
and gathering data about the curious
substance known as lunar dust. Then
the probe, which goes by the acronym
Ladee (pronounced laddie), will take a
death plunge into the rocky surface of
the subject it is studying.
The results of the scientific program
could be helpful in preparing for future
manned missions to the moon.
Although NASA currently does not have
such plans, some members of Congress
have called on the space agency to
return to the moon rather than
pursuing its current space objectives.
Although there is wide agreement that
NASA should ultimately aim for a
manned flight to Mars, that goal is far
off. The more immediate plan, which
has been criticized on Capitol Hill, is to
capture an asteroid and tow it closer to
home so astronauts can visit it.
But NASA has continued sending
unmanned spacecraft to the moon; the
coming mission will be the third to go
there in five years. While scientists are
excited about what the experiment may
yield, they are also concerned about
the absence of future moon voyages on
NASA’s schedule.
“If you’re going to fly this mission with
the goal of understanding the
atmosphere and how dust might affect
future human missions, and you don’t
have the future human missions, then
part of the reason for the mission
disappears,” said David Kring, senior
staff scientist at the Lunar and
Planetary Institute, a NASA-financed
research institute in Houston.
Even if NASA sits on the sidelines,
traffic to the moon will be busy. China
announced last week that it would land
its first exploratory rover on the moon
by the end of the year. India, Japan,
Russia and the European Space Agency
also have unmanned missions in the
works. And Google is sponsoring a
competition called the Lunar X Prize,
offering up to $20 million to the first
company that can send a robotic
spacecraft to the moon by 2015 and
make it perform certain tasks.
The Ladee spacecraft was conceived
when NASA was also planning new
manned missions to the moon, which
would have been the first since 1972.
But the Obama administration
canceled that program, called
Constellation, in 2010, calling it over
budget and behind schedule. Ladee
stayed in the pipeline.
The spacecraft will search for water in
the very thin lunar atmosphere, which
is estimated to be 1/100,000th the
density of Earth’s, perhaps similar to
Mercury’s. Scientists want to find out
how the ice on the moon’s poles
managed to get there, said Richard
Elphic, project scientist for the mission.
They speculate that water molecules in
the moon’s atmosphere may have
migrated toward the poles and frozen
in place, he said.
Evidence of water below the moon’s
surface was discovered in recent years
by a NASA-financed instrument aboard
an Indian spacecraft, Chandrayaan-1.
Data collected from the coming mission
could help complete the picture of the
moon’s water cycle, Dr. Elphic said.
The orbiter will also examine the
movements of lunar dust. “Dust” is a
bit of a misnomer, the scientists said:
the crushed debris is extremely fine but
also has jagged, sharp edges, since there
is no wind or water on the moon’s
surface to wear it down.
“It’s certainly more annoying than
terrestrial dust,” said Sarah Noble,
program scientist for the mission. “It’s
like shards of glass, and it sticks to
everything. If it gets into your eyes or
your skin, it’s abrasive and it hurts. It
also really gums up machinery.”
The dust poses a risk to robots and
humans alike, as it can wreak havoc on
equipment and spacesuits.
Understanding the way the dust moves
through the atmosphere will help
scientists better prepare for longer
missions on the moon, Dr. Elphic said.
Not everyone agrees that dust is a
major concern. “Dust on the lunar
surface does not pose a serious risk to
future lunar exploration,” Dr. Kring
said, pointing out that astronauts
managed to survive the dust without
major problems. But he still saw value
in the dust inquiry, saying, “We always
want to reduce the risk, and to
understand the dust phenomenon in
and of itself is worthwhile.”
NASA said the launching would break
technological ground. Previously,
spacecraft were custom-made for each
mission and the models were not
reusable. But this spacecraft was
designed for assembly-line production,
so that future missions could save
money by using identical components.
The spacecraft’s design and
construction cost $125 million out of a
mission price of $250 million, said
Dwayne Brown, a NASA spokesman. If
the same design were used again, Mr.
Brown said, NASA estimates that the
cost would drop to $90 million for the
first spacecraft and then over time to
$55 million each. At the moment,
though, NASA does not have other
projects lined up to reuse the model, he
said.
The spacecraft will ride on the maiden
voyage of the Minotaur V rocket built
by the Orbital Sciences Corporation,
one of several private contractors
NASA has turned to in recent years to
supply rockets for its missions. The
launching will be the first lunar
mission for Orbital, as well as the first
moon journey departing from Wallops
Island.
In 2009 and 2011, Orbital lost two
NASA satellites in failed launching of its
Taurus XL rocket, costing the agency
more than $600 million.
For this mission to succeed, Ladee will
need to launch, separate from the
Minotaur V, and insert itself into lunar
orbit. Then, NASA will be able to begin
its experiments.
“Once we’re on the moon, we’ll breathe
a big sigh of relief,” Dr. Noble said.
