Aura (EOS CH-1)
|Mission type||Earth Observation|
|Launch mass||2,970 kilograms (6,550 lb)|
|Dimensions||4.70 m x 17.37 m x 6.91 m|
|Start of mission|
|Launch date||July 15, 2004, 10:01:51UTC|
|Rocket||Delta II 7920-10L|
|Launch site||Vandenberg SLC-2W|
|Semi-major axis||7,080.7 kilometers (4,399.7 mi)|
|Perigee||708 kilometers (440 mi)|
|Apogee||710 kilometers (440 mi)|
|Argument of perigee||89.5089 degrees|
|Mean anomaly||270.6277 degrees|
|Epoch||25 January 2015, 03:15:27 UTC|
Aura (EOS CH-1) is a multi-national NASA scientific research satellite in orbit around the Earth, studying the Earth's ozone layer, air quality and climate. It is the third major component of the Earth Observing System (EOS) following on Terra (launched 1999) and Aqua (launched 2002). Aura follows on from the Upper Atmosphere Research Satellite (UARS). The Aura spacecraft is healthy and is expected to operate until at least 2022, likely beyond.
All satellites have an equatorial crossing time at about 1:30 in the afternoon, thus the name 'A (Afternoon) Train'.
As of 2015, there had been 1589 Aura-related journal articles. The scientific findings of these studies address key NASA research objectives related to stratospheric composition, air quality, and climate change.
Aura has suffered some minor anomalies that have not proven to be mission ending.
On January 12, 2005, a solar array connector partially "unzipped" losing temperature telemetry and power from part of the solar array. On March 12, 2010, Aura was believed to be struck by a micro-meteor that resulted in the loss of power from one-half of one of the 11 solar panels. Despite the loss of power from these events and other anomalies in the array regulation electronics, resulting in an estimated loss of 25 out of 132 solar strings, the mission is estimated to have ample power capabilities to supply the mission until fuel runs out.
Aura carries four instruments for studies of atmospheric chemistry:
- HIRDLS — High Resolution Dynamics Limb Sounder — measures infrared radiation from ozone, water vapor, CFCs, methane and nitrogen compounds. Developed jointly with the United Kingdom Natural Environment Research Council. HIRDLS capabilities were compromised at launch when a piece of Kapton film in the instrument came loose and blocked much of the aperture, allowing only a partial view. The blockage prevented certain types of observations and necessitated the development of algorithms to remove the effects due to the blockage. This unanticipated algorithm developmental effort delayed data delivery. The HIRDLS chopper motor stalled on March 17, 2008, and HIRDLS has not produced science since.
- MLS — Microwave Limb Sounder — measures emissions from ozone, chlorine and other trace gases, and clarifies the role of water vapor in global warming.
- OMI — Ozone Monitoring Instrument — uses ultraviolet and visible radiation to produce daily high-resolution maps. Developed by the Finnish Meteorological Institute and the Netherlands Agency for Aerospace Programmes.
- TES — Tropospheric Emission Spectrometer — measures tropospheric ozone in infrared wavelengths, also carbon monoxide, methane and nitrogen oxides. Despite repeated incidents of the TES Interferometer Control System (ICS) motor stalling, stalls which took days or weeks to recover from, the instrument is still providing science data.
- "AURA Satellite details 2004-026A NORAD 28376". N2YO. 25 January 2015. Retrieved 25 January 2015.
- Liu, Guosheng (22 June 2015). "NASA Earth Science Senior Review 2015" (PDF). Retrieved 17 October 2017.
- Fisher, Dominic (31 August 2016). "Mission Status at Aura Science Team MOWG Meeting" (PDF). Retrieved 17 October 2017.
- Schoeberl, M (2011). "Aura Senior Review" (PDF). Retrieved 17 October 2017.