Searching for Water, NASA Will Crash a Spacecraft on the Moon
WASHINGTON, DC, April 11, 2006 (ENS) - In search of water ice, the National Aeronautics and Space Administration (NASA) plans to crash an impactor satellite onto the moon early in 2009.
In a press briefing at NASA headquarters Monday, NASA officials explained the space agency's concept for the mission, designed as a prelude to placing humans on the moon by the year 2020.
The impactor satellite, called the Lunar Crater Observation and Sensing Satellite (LCROSS), will fly as a secondary payload on the Evolved Expendable Launch Vehicle that will launch the orbiter from NASA's Kennedy Space Center, Florida in October 2008, if all goes well.
“The LCROSS mission gives the agency an excellent opportunity to answer the question about water ice on the moon,” said Daniel Andrews of NASA Ames, whose team proposed LCROSS.
The Lunar Reconnaissance Orbiter (LRO) will begin orbiting the moon, and LCROSS and the upper stage of the expendable rocket will continue their journey, traveling around the Earth twice, taking about 90 days.
Above the crash site, LCROSS sensors will measure water ice, water vapor and other compounds.
Then, Andrews said, “we fly right through that plume, so we have an excellent opportunity to measure what is going on and what is there, all the way down into some mineralogical angles. We’re going to learn a lot from this.”
After it captures data from the plume and sends it back to Earth, the LCROSS satellite also will crash into the moon, creating a second plume visible to lunar-orbiting spacecraft and observatories on Earth.
“One of the side benefits of this mission,” Andrews said, “is that we will have the opportunity for amateur astronomers back on Earth with reasonable grade telescopes to be able to witness the plume that develops.”
It is a great way, he said, “to engage the public in this very interesting mission.”
"This type of payload is not new to NASA," said Scott Horowitz, associate administrator for the Exploration Systems Mission Directorate, who made the selection. "We are taking advantage of the payload capability of the launch vehicle to conduct additional high risk/high payoff science to meet Vision for Space Exploration goals."
LRO and LCROSS are the first of many robotic missions NASA plans to conduct between 2008 and 2016 to study, map and learn about the lunar surface to prepare for the return of astronauts to the moon.
According to NASA's Vision for Space Exploration, the agency plans to send astronauts back to the moon by 2020 and, eventually, to set up an outpost there as a step toward Mars and beyond.
Whether establishing a moon base will be doable depends on the presence of water, as any colonists would need water to drink and grow plants.
In addition, water, composed of two parts hydrogen and one part oxygen, can be broken down to make breathable oxygen and rocket fuel, composed of a different balance of oxygen and hydrogen.
Water is useful to block space radiation, the scientists said, envisioning that surrounding a moon base with about three feet of water would help protect explorers from solar flares and cosmic rays.
To help find out if the moon has water, another instrument, the Diviner, will map the temperature of the moon's surface so scientists can search for places where ice could exist. Even in the permanent shadows of polar craters, temperatures must be very low for ice to resist evaporation.
An instrument called the Cosmic Ray Telescope for the Effects of Radiation (CRaTER) aboard the LRO will help measure and map the moon's radiation environment.
"We really need to know more about the radiation environment on the moon, especially if people will be staying there for more than just a few days," said Harlan Spence, a Boston University astronomy professor, in a September 2005 NASA fact sheet.
Spence and colleagues will collect data by placing the radiation detectors in CRaTER behind various thicknesses of a special plastic that has similar density and composition to human tissue.
The LRO’s other radiation sensing instrument, the Lunar Exploration Neutron Detector (LEND), is partially funded by the Russian Federal Space Agency, Roscosmos. LEND will detect radiation from neutron particles that emanate from the lunar surface to measure how energetic the neutrons are. The more energetic they are, the more damaging to humans the particles would be.
Before the end of the next decade, NASA says, astronauts will again explore the surface of the moon. "And this time, we're going to stay, building outposts and paving the way for eventual journeys to Mars and beyond," the agency says on its website.
The crew exploration vehicle will be designed to carry four astronauts to and from the moon, support up to six crewmembers on future missions to Mars, and deliver crew and supplies to the International Space Station.
The new crew vehicle will be shaped like an Apollo capsule, but it will be three times larger, allowing four astronauts to travel to the moon at a time.
Plans call for solar panels to provide power, and both the capsule and the lunar lander to use liquid methane in their engines. NASA plans for future astronauts to convert Martian atmospheric resources into methane fuel.
The new ship can be reused up to 10 times. After the craft parachutes to dry land, with a splashdown as a backup option, NASA plans to recover it, replace the heat shield and launch it again.