Monday, January 30, 2012

First of NASA's GRAIL spacecraft enters Moon orbit

NASA's GRAIL spacecraftThe first of two NASA spacecraft to study the moon in unprecedented detail has entered lunar orbit.

NASA's Gravity Recovery And Interior Laboratory (GRAIL)-A spacecraft successfully completed its planned main engine burn at 2 p.m. PST (5 p.m. EST) today. As of 3 p.m. PST (6 p.m. EST), GRAIL-A is in an orbit of 56 miles by 5,197 miles (90 kilometers by 8,363 kilometers) around the moon that takes approximately 11.5 hours to complete.

"My resolution for the new year is to unlock lunar mysteries and understand how the moon, Earth and other rocky planets evolved," said Maria Zuber, GRAIL principal investigator at the Massachusetts Institute of Technology in Cambridge. "Now, with GRAIL-A successfully placed in orbit around the moon, we are one step closer to achieving that goal."

The next mission milestone occurs tomorrow when GRAIL-A's mirror twin, GRAIL-B, performs its own main engine burn to place it in lunar orbit. At 3 p.m. PST (6 p.m. EST) today, GRAIL-B was 30,018 miles (48,309 kilometers) from the moon and closing at a rate of 896 mph (1,442 kilometers per hour). GRAIL-B's insertion burn is scheduled to begin tomorrow, Jan. 1, at 2:05 p.m. PST (5:05 p.m. EST) and will last about 39 minutes.

"With GRAIL-A in lunar orbit we are halfway home," said David Lehman, GRAIL project manager at NASA's Jet Propulsion Laboratory in Pasadena, Calif. "Tomorrow may be New Year's everywhere else, but it's another work day around the moon and here at JPL for the GRAIL team."

Once both spacecraft are confirmed in orbit and operating, science work will begin in March. The spacecraft will transmit radio signals precisely defining the distance between them as they orbit the moon in formation. As they fly over areas of greater and lesser gravity caused by both visible features, such as mountains and craters, and masses hidden beneath the lunar surface, the distance between the two spacecraft will change slightly.

Scientists will translate this information into a high-resolution map of the moon's gravitational field. The data will allow scientists to understand what goes on below the lunar surface. This information will increase knowledge of how Earth and its rocky neighbors in the inner solar system developed into the diverse worlds we see today.

Wednesday, January 25, 2012

Voyager Instrument Cooling After Heater Turned off


It is now operating at a temperature below minus 79 degrees Celsius (minus 110 degrees Fahrenheit), the coldest temperature that the instrument has ever endured. This heater shut-off is a step in the careful management of the diminishing electrical power so that the Voyager spacecraft can continue to collect and transmit data through 2025.

At the moment, the spectrometer continues to collect and return data. It was originally designed to operate at temperatures as low as minus 35 degrees Celsius (minus 31 degrees Fahrenheit), but it has continued to operate in ever chillier temperatures as heaters around it have been turned off over the last 17 years. It was not known if the spectrometer would continue working, but since 2005, it has been operating at minus 56 degrees Celsius (69 degrees Fahrenheit.) So engineers are encouraged that the instrument has continued to operate, even after the nearby heater was turned off in December. (The spectrometer is likely operating at a temperature somewhat lower than minus 79 degrees Celsius, or minus 110 degrees Fahrenheit, but the temperature detector does not go any lower.)

Scientists and mission managers will continue to monitor the spectrometer’s performance. It was very active during Voyager 1’s encounters with Jupiter and Saturn, and since then an international team led by scientists in France has been analyzing the spectrometer’s data.

This latest heater shut-off was actually part of the nearby infrared spectrometer, which itself has not been operational on Voyager 1 since 1998.

The Voyager spacecraft were built by NASA’s Jet Propulsion Laboratory in Pasadena, Calif., which continues to operate both. JPL is a division of the California Institute of Technology in Pasadena. The Voyager missions are a part of the NASA Heliophysics System Observatory, sponsored by the Heliophysics Division of the Science Mission Directorate in Washington.

Thursday, January 19, 2012

2012 Lunar Extreme Program and Workshop for Bay Area High School Teachers and Students

2012 Lunar Extreme Program
Dynamic Response of the Environment At the Moon – is one of several teams comprising the NASA Lunar Science Institute. The purpose of DREAM is to investigate the response of the lunar environment to the harsh and ever-changing conditions in space, including extreme events such as solar storms and impacts. DREAM is looking for two teams of high school teachers and students (4-6 students per teacher) in the Bay Area of California who would like to participate in the Lunar Extreme Program for Jan.-June 2012, culminating in participation at a Lunar Extreme Workshop with DREAM scientists on June 18-22, 2012, at Ames Research Center in Moffett Field, California. The target audience for this program are students who have already been exposed to physics, Earth science, chemistry, or computer modeling, and the teachers of these subjects. Teachers will be provided with small stipends for their participation. Participants will be notified of their acceptance by Dec. 16. To learn more and to apply,

Tuesday, January 3, 2012

Fastest Rotating Star Found in Neighboring Galaxy


The massive, bright young star, called VFTS 102, rotates at a million miles per hour, or 100 times faster than our sun does. Centrifugal forces from this dizzying spin rate have flattened the star into an oblate shape and spun off a disk of hot plasma, seen edge on in this view from a hypothetical planet. The star may have "spun up" by accreting material from a binary companion star. The rapidly evolving companion later exploded as a supernova. The whirling star lies 160,000 light-years away in the Large Magellanic Cloud, a satellite galaxy of the Milky Way.