Posted on by Nancy Atkinson

LRO Successfully In Lunar Orbit; LCROSS Provides Flyby Video

LCROSS flyby video capture. Credit: NASA

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The Lunar Reconnaissance Orbiter fired its braking thrusters for 40 minutes early today, successfully inserting the spacecraft into orbit around the Moon. Over the next several days, LRO’s instruments will be turned on and its orbit will be fine-tuned. Then LRO will begin its primary mission of mapping the lunar surface to find future landing sites and searching for resources that would make possible a permanent human presence on the moon. Also, early Tuesday, the companion mission Lunar Crater Observation and Sensing Satellite (LCROSS) sent back live video as it flew 9,000 km above the Moon, as it enters its elongated Earth orbit, which will bring it on course to impact the Moon’s south pole in October.

The two spacecraft reached the Moon four-and-a-half days after launch. LRO’s rocket firing began around 9:20 GMT (5:47 a.m. EDT) and ended at 10:27 GME (6:27 a.m. EDT), putting the spacecraft into an orbit tilted 30 degrees from the moon’s poles with a low point of 218 km (136 miles) and a high point of 3,000 km (1,926 miles). Over the next five days, additional rocket firings will put the spacecraft into the correct orbit for making its observations for the prime mission, which lasts a year — a polar orbit of about 31 miles, or 50 kilometers, the closest any spacecraft has orbited the moon.

Meanwhile, at 12:20 GMT (8:20 EDT) on Tuesday, LCROSS made a relatively close flyby of the Moon, sending back live streaming video. Watch the replay here.

LCROSS on its way to impact. Credit: NASA
LCROSS on its way to impact. Credit: NASA

LCROSS is now in its “cruise phase” and will be monitored by the mission operations team. During the flyby, the science team was able to obtain the data needed to focus and adjust the cameras and spectrometers correctly for impact.

LCROSS will never actually be lunar orbit, but is working its way to an elongated Earth orbit which will eventually bring it to the correct orientation for meeting up with the south pole of the Moon later this year. LCROSS will search for water ice on the moon by sending the spent upper-stage Centaur rocket to impact part of a polar crater in permanent shadows. The LCROSS spacecraft will fly into the plume of dust left by the impact and measure the properties before also colliding with the lunar surface.

Posted on by Nancy Atkinson

Make Room at the Moon

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Lunar orbit is getting to be a busy place, with several different countries sending spacecraft to the moon. Currently orbiting the Moon are Japan’s Kaguya (also known as SELENE) spacecraft, which has been sending back 3-D movies of the lunar surface, and China’s Chang-e 1, which will gather information on the Moon’s chemical composition with its various cameras, spectrometers and other scientific equipment. In addition, two new missions to the moon will launch this year: India’s Chandrayaan-1 and NASA’s Lunar Reconnaissance Orbiter.

Chandrayaan, which means “journey to the moon” in Hindi, will study the moon at many wavelengths, from X-ray, visible and near-infrared to microwave. It will orbit the moon at just 100 km above the surface. The mission is scheduled to launch on April 9.

“The low orbit will give us really high resolution data,” says Detlef Koschny, Chandrayaan project scientist. The principal mission objective is to map the Moon’s surface in unprecedented detail. Current lunar maps show detail from 30 – 100 meters across. Chandrayaan will produce maps with a resolution of between 5 and 10 meters across the whole surface of the moon.

The European Space Agency (ESA) is collaborating with Indian Space Research Organization (ISRO) for the Chandrayaan-1 mission. A Compact Imaging X-ray Spectrometer will produce x-ray spectroscopic mapping of the moon, and the Infrared Spectrometer will observe the Moon’s chemical composition. Another ESA instrument is the Sub-keV Atom Reflecting Analyzer, which will study the interaction between electrically charged particles from the solar wind and Moon’s surface.

Eight other instruments complete the suite of science instruments, including a 29-kg landing probe which will be dropped onto the Moon’s surface at the beginning of the mission to conduct investigations.

Meanwhile, the Lunar Reconnaissance Orbiter (LRO) is currently undergoing testing at Goddard Spaceflight Center to get ready for its launch on October 28 of this year. LRO will spend at least a year mapping the surface of the moon. Data from the orbiter will help NASA select safe landing sites for astronauts, identify lunar resources and study how the moon’s environment will affect humans.

Engineers at Goddard are building the orbiter and testing spacecraft components to ready them for the harsh environment of space. After a component or entire subsystem is qualified, it is integrated into the LRO spacecraft. The core suite of avionics for the orbiter is assembled and undergoing system tests.

“This is a major milestone for the mission,” said Craig Tooley, LRO project manager at Goddard. “Our team has been working nearly around the clock to get us to this point. Reaching this milestone keeps us on the path to sending LRO to the moon later this year.”

Once fully integrated, the spacecraft will ship to NASA’s Kennedy Space Center, Florida in August in preparation for launch. The orbiter and the Lunar Crater Observation and Sensing Satellite (LCROSS) will launch aboard an Atlas V rocket. LCROSS will study the poles of the moon to confirm the presence or absence of water ice in a permanently shadowed craters. The trip to the moon for the spacecraft will take approximately four days. The Lunar Reconnaissance Orbiter initially will enter an elliptical orbit, also called the commissioning orbit. Once moved into its final orbit, a circular polar orbit approximately 31 miles above the moon, the spacecraft’s instruments will map the lunar surface.

Original News Sources: Chandrayaan Press Release, LRO press release