Miniature X-ray Solar Spectrometer CubeSat

MinXSS

The sun-facing side of the MinXSS spacecraft. The two hinged solar panels are in their deployed state. The science instrument apertures can be seen near the top. The tape-measure antenna extends beyond the top of the photo. Image taken after final integration of the spacecraft.
Mission type	Solar physics, Space weather, Near space research
Operator	CU/LASP
COSPAR ID	1998-067HU
SATCAT no.	41474U
Website	lasp.colorado.edu/home/minxss
Mission duration	Flight model 1: 6 months (planned), 11.66 months (actual) Flight model 2: 5 years (planned) 8 years (elasped)
Spacecraft properties
Spacecraft type	3U CubeSat
Manufacturer	CU/LASP
Launch mass	3.5163 kg
Dry mass	3.5163 kg
Power	Consumes: 8.0 W (science mode) 5.3 W (safe mode) 2.8 W (phoenix mode) Max generation: 19 W
Start of mission
Launch date	December 6, 2015, 08:44:57 (2015-12-06UTC08:44:57Z) UTC
Rocket	Atlas V 401
Launch site	Kennedy Space Center
Contractor	United Launch Alliance
Entered service	2016 May 16
End of mission
Last contact	2017-05-06 02:37:26 UTC
Decay date	2017 May 6
Orbital parameters
Reference system	Geocentric
Regime	Low Earth
Perigee altitude	402 kilometers (250 mi)
Apogee altitude	402 kilometers (250 mi)
Inclination	51.65 degrees
Period	92.69 minutes
Epoch	July 4, 2016[1]
Instruments
Modified Amptek X123 silicon drift detector Sun Position Sensor (SPS), X-ray Photometer (XP)

The Miniature X-ray Solar Spectrometer (MinXSS) CubeSat was the first launched National Aeronautics and Space Administration Science Mission Directorate CubeSat with a science mission.^[2] It was designed, built, and operated primarily by students at the University of Colorado Boulder with professional mentorship and involvement from professors, scientists, and engineers in the Aerospace Engineering Sciences department and the Laboratory for Atmospheric and Space Physics, as well as Southwest Research Institute, NASA Goddard Space Flight Center, and the National Center for Atmospheric Research's High Altitude Observatory. The mission principal investigator is Dr. Thomas N. Woods and co-investigators are Dr. Amir Caspi, Dr. Phil Chamberlin, Dr. Andrew Jones, Rick Kohnert, Professor Xinlin Li, Professor Scott Palo, and Dr. Stanley Solomon. The student lead (project manager, systems engineer) was Dr. James Paul Mason, who has since become a Co-I for the second flight model of MinXSS.

MinXSS launched on 2015 December 6 to the International Space Station as part of the Orbital ATK Cygnus CRS OA-4 cargo resupply mission.^[3] The launch vehicle was a United Launch Alliance Atlas V rocket in the 401 configuration. CubeSat ridesharing was organized as part of NASA ELaNa-IX. Deployment from the International Space Station was achieved with a NanoRacks CubeSat Deployer on 2016 May 16.^[4] Spacecraft beacons were picked up soon after by amateur radio operators around the world.^[5][6] Commissioning of the spacecraft was completed on 2016 June 14^[7] and observations of solar flares captured nearly continuously since then.^[8] The altitude rapidly decayed in the last week of the mission as atmospheric drag increased exponentially with altitude. The last contact from MinXSS came on 2017-05-06 at 02:37:26 UTC from a HAM operator in Australia. At that time, some temperatures on the spacecraft were already in excess of 100 °C. (One temperature of >300 °C indicated that the solar panel had disconnected, suggesting this contact was only moments before disintegration.)^[9] Science data spanning the entire mission are publicly available.^[10]