Microgravity testing

A beach ball-sized satellite developed by a team of students at University of Colorado Boulder (CU-Boulder), to better understand the impact of atmospheric drag on satellite orbits, is scheduled for launch by Nasa on 15 September.

Set to be launched from Vandenberg Air Force Base in California, the Drag and Atmospheric Neutral Density Explorer satellite, or DANDE, has been developed to assess the density variations of thermosphere, a layer of Earth’s atmosphere, at altitudes from about 200-300 miles above Earth.

DANDE, which has Colorado Space Grant Consortium (COSGC) director Chris Koehler as the primary investigator, measures nearly 20in in diameter and weighs more than 100lb.

The spacecraft will carry an accelerometer, a wind and temperature spectrometer, an orientation control system and radio equipment for real-time transmission of data to Earth and an onboard computer, and will be deployed into a polar orbit

The accelerometer can sense the movement, speed and direction of spacecraft to enable scientists a better understanding of drag forces, while the wind and temperature spectrometer aboard the satellite will deliver data on the varying drag forces in the thermosphere.

"The accelerometer can sense the movement, speed and direction of spacecraft to enable scientists a better understanding of drag forces."

It will identify the type of particles that are impacting the spacecraft, along with their angles and collision velocities.

DANDE team anticipates collecting continuous information from the spacecraft for nearly 1.5 years, downloading it several times every day to the COSGC satellite control facility in the CU-Boulder engineering college.

The satellite will launch onboard a commercial Falcon-9 Space-X rocket, which will also carry satellites from the Canadian Space Agency, Utah State University and Cornell University.

CU-Boulder students trialled the behaviour of DANDE satellite parts in a modified Nasa jet that creates microgravity conditions.

Started in 2007 with an $110,000 seed grant from the US Air Force Office of Scientific Research, the DANDE programme won the University Nanosatellite Flight Competition Review conducted by AFOSR in 2009, providing the students with a launch opportunity.

Image: CU-Boulder students trialled the behaviour of DANDE satellite parts in a modified Nasa jet that creates microgravity conditions. Photo: courtesy of University of Colorado Boulder.

Defence Technology