Names | EOS CH-1 |
---|---|
Mission type | Earth Observation |
Operator | NASA |
COSPAR ID | 2004-026A |
SATCAT no. | 28376 |
Website | aura.gsfc.nasa.gov |
Mission duration | 20 years, 14 days (elapsed) |
Spacecraft properties | |
Bus | T330 (AB-1200) |
Manufacturer | Northrop Grumman |
Launch mass | 2,970 kilograms (6,550 lb) |
Dimensions | 4.70 m x 17.37 m x 6.91 m |
Power | 4.6 kW |
Start of mission | |
Launch date | July 15, 2004, 10:01:51 UTC |
Rocket | Delta II 7920-10L D-306 |
Launch site | Vandenberg SLC-2W |
End of mission | |
Last contact | 2036 | (planned)
Decay date | 2048 (planned) |
Orbital parameters | |
Reference system | Geocentric |
Regime | Sun-synchronous |
Semi-major axis | 7,080.7 kilometers (4,399.7 mi) |
Eccentricity | 0.0001111 [1] |
Perigee altitude | 708 kilometers (440 mi) [1] |
Apogee altitude | 710 kilometers (440 mi) [1] |
Inclination | 98.22 degrees [1] |
Period | 98.83 minutes [1] |
RAAN | 96.8126 degrees |
Argument of perigee | 89.5089 degrees |
Mean anomaly | 270.6277 degrees |
Mean motion | 14.57112850 |
Epoch | 25 January 2015, 03:15:27 UTC [1] |
Large Strategic Science Missions Earth Science Division |
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. [2] 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). Aura is a joint mission between NASA, the Netherlands, Finland, and the U.K. [3] The Aura spacecraft is healthy and is expected to operate until at least 2023, likely beyond. [4]
The name "Aura" comes from the Latin word for air. The satellite was launched from Vandenberg Air Force Base on July 15, 2004, aboard a Delta II 7920-10L rocket.
The Aura spacecraft has a mass of about 1,765 kg (3,891 lb). The body is 6.9 m (23 ft) long with the extended single solar panel about 15 m (49 ft) long.
Aura flies in a Sun-synchronous orbit, in formation with three other satellites, collectively known as the "A Train"; it is last in the formation. The other satellites in the formation are:
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. [4]
Aura has suffered some minor, non-mission ending anomalies.
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 lost power from one-half of one of the 11 solar panels and this was attributed to a Micrometeoroid Orbital Debris (MMOD) strike. These events, and 9 other anomalies in the array regulation electronics (ARE), have resulted in an estimated loss of 33 out of 132 solar strings. [5] Nonetheless, the mission is estimated to have ample power capabilities to supply the mission until fuel runs out. [6] [7] [8]
A Formatter Multiplexer Unit (FMU) / Solid State Recorder (SSR) anomaly was first detected in December 2007. New symptoms were detected in January 2017 and starting on March 21, 2017, Aura no longer recorded housekeeping data to partition 31. [6]
In December 2016, reaction wheel #3 spun down. It was recovered 10 days later. [6]
On January 31, 2018, the TES instrument was decommissioned due to degrading operations. A mechanical arm on the instrument began stalling intermittently in 2010, affecting TES's ability to collect data continuously. Despite the adaptations of TES operators, the degradation got worse with time and in 2017 the instrument lost operations for approximately half the year. It will continue to receive enough power to keep it from getting too cold which could affect the two remaining functioning instruments. [9]
As of 2020, the expected constellation exit date is December 2023. An extended mission, below the A-train could push decommissioning back to late 2025 or as far as 2036. Predicted re-entry would be 2048. [7] [5]
Aura carries four instruments for studies of atmospheric chemistry:
Satellite temperature measurements are inferences of the temperature of the atmosphere at various altitudes as well as sea and land surface temperatures obtained from radiometric measurements by satellites. These measurements can be used to locate weather fronts, monitor the El Niño-Southern Oscillation, determine the strength of tropical cyclones, study urban heat islands and monitor the global climate. Wildfires, volcanos, and industrial hot spots can also be found via thermal imaging from weather satellites.
The Goddard Space Flight Center (GSFC) is a major NASA space research laboratory located approximately 6.5 miles (10.5 km) northeast of Washington, D.C. in Greenbelt, Maryland, United States. Established on May 1, 1959 as NASA's first space flight center, GSFC employs about 10,000 civil servants and contractors. Named for American rocket propulsion pioneer Robert H. Goddard, it is one of ten major NASA field centers. GSFC is partially within the former Goddard census-designated place; it has a Greenbelt mailing address.
Terra is a multi-national scientific research satellite operated by NASA in a Sun-synchronous orbit around the Earth. It takes simultaneous measurements of Earth's atmosphere, land, and water to understand how Earth is changing and to identify the consequences for life on Earth. It is the flagship of the Earth Observing System (EOS) and the first satellite of the system which was followed by Aqua and Aura. Terra was launched in 1999.
Clouds and the Earth's Radiant Energy System (CERES) is an on-going NASA climatological experiment from Earth orbit. The CERES are scientific satellite instruments, part of the NASA's Earth Observing System (EOS), designed to measure both solar-reflected and Earth-emitted radiation from the top of the atmosphere (TOA) to the Earth's surface. Cloud properties are determined using simultaneous measurements by other EOS instruments such as the Moderate Resolution Imaging Spectroradiometer (MODIS). Results from the CERES and other NASA missions, such as the Earth Radiation Budget Experiment (ERBE), could enable nearer to real-time tracking of Earth's energy imbalance (EEI) and better understanding of the role of clouds in global climate change.
MOPITT is an ongoing astronomical instrument aboard NASA's Terra satellite that measures global tropospheric carbon monoxide levels. It is part of NASA's Earth Observing System (EOS), and combined with the other payload remote sensors on the Terra satellite, the spacecraft monitors the Earth's environment and climate changes. Following its construction in Canada, MOPITT was launched into Earth's orbit in 1999 and utilizes gas correlation spectroscopy to measure the presence of different gases in the troposphere. The fundamental operations occur in its optical system composed of two optical tables holding the bulk of the apparatus. Results from the MOPITT enable scientists to better understand carbon monoxide's effects on a global scale, and various studies have been conducted based on MOPITT's measurements.
The Earth Observing System (EOS) is a program of NASA comprising a series of artificial satellite missions and scientific instruments in Earth orbit designed for long-term global observations of the land surface, biosphere, atmosphere, and oceans. Since the early 1970s, NASA has been developing its Earth Observing System, launching a series of Landsat satellites in the decade. Some of the first included passive microwave imaging in 1972 through the Nimbus 5 satellite. Following the launch of various satellite missions, the conception of the program began in the late 1980s and expanded rapidly through the 1990s. Since the inception of the program, it has continued to develop, including; land, sea, radiation and atmosphere. Collected in a system known as EOSDIS, NASA uses this data in order to study the progression and changes in the biosphere of Earth. The main focus of this data collection surrounds climatic science. The program is the centrepiece of NASA's Earth Science Enterprise.
The Upper Atmosphere Research Satellite (UARS) was a NASA-operated orbital observatory whose mission was to study the Earth's atmosphere, particularly the protective ozone layer. The 5,900-kilogram (13,000 lb) satellite was deployed from Space Shuttle Discovery during the STS-48 mission on 15 September 1991. It entered Earth orbit at an operational altitude of 600 kilometers (370 mi), with an orbital inclination of 57 degrees.
Aqua is a NASA scientific research satellite in orbit around the Earth, studying the precipitation, evaporation, and cycling of water. It is the second major component of the Earth Observing System (EOS) preceded by Terra and followed by Aura.
Tropospheric Emission Spectrometer or TES was a satellite instrument designed to measure the state of the earth's troposphere.
The Total Ozone Mapping Spectrometer (TOMS) was a NASA satellite instrument, specifically a spectrometer, for measuring the ozone layer. Of the five TOMS instruments which were built, four entered successful orbit. The satellites carrying TOMS instruments were:
The advanced microwave sounding unit (AMSU) is a multi-channel microwave radiometer installed on meteorological satellites. The instrument examines several bands of microwave radiation from the atmosphere to perform atmospheric sounding of temperature and moisture levels.
The microwave limb sounder (MLS) experiments measure microwave thermal emission from the limb (edge) of Earth's upper atmosphere. The data is used to create vertical profiles of atmospheric gases, temperature, pressure, and cloud ice.
Over the last two centuries many environmental chemical observations have been made from a variety of ground-based, airborne, and orbital platforms and deposited in databases. Many of these databases are publicly available. All of the instruments mentioned in this article give online public access to their data. These observations are critical in developing our understanding of the Earth's atmosphere and issues such as climate change, ozone depletion and air quality. Some of the external links provide repositories of many of these datasets in one place. For example, the Cambridge Atmospheric Chemical Database, is a large database in a uniform ASCII format. Each observation is augmented with the meteorological conditions such as the temperature, potential temperature, geopotential height, and equivalent PV latitude.
The ozone monitoring instrument (OMI) is a nadir-viewing visual and ultraviolet spectrometer aboard the NASA Aura spacecraft. Aura flies in formation about 15 minutes behind Aqua, both of which orbit the Earth in a polar Sun-synchronous pattern. Aura was launched on July 15, 2004, and OMI has collected data since August 9, 2004. OMI can distinguish between aerosol types, such as smoke, dust, and sulfates, and can measure cloud pressure and coverage, which provide data to derive tropospheric ozone. OMI follows in the heritage of TOMS, SBUV, GOME, SCIAMACHY, and GOMOS. OMI measurements cover a spectral region of 264–504 nm (nanometers) with a spectral resolution between 0.42 nm and 0.63 nm and a nominal ground footprint of 13 × 24 km2 at nadir. The Aura satellite orbits at an altitude of 705 km in a sun-synchronous polar orbit with an exact 16-day repeat cycle and with a local equator crossing time of 13. 45 on the ascending node. The orbital inclination is 98.1 degrees, providing latitudinal coverage from 82° N to 82° S. It is a wide-field-imaging spectrometer with a 114° across-track viewing angle range that provides a 2600 km wide swath, enabling measurements with a daily global coverage. OMI is continuing the TOMS record for total ozone and other atmospheric parameters related to ozone chemistry and climate.
The atmospheric infrared sounder (AIRS) is one of six instruments flying on board NASA's Aqua satellite, launched on May 4, 2002. The instrument is designed to support climate research and improve weather forecasting.
The Joint Polar Satellite System (JPSS) is the latest generation of U.S. polar-orbiting, non-geosynchronous, environmental satellites. JPSS will provide the global environmental data used in numerical weather prediction models for forecasts, and scientific data used for climate monitoring. JPSS will aid in fulfilling the mission of the U.S. National Oceanic and Atmospheric Administration (NOAA), an agency of the Department of Commerce. Data and imagery obtained from the JPSS will increase timeliness and accuracy of public warnings and forecasts of climate and weather events, thus reducing the potential loss of human life and property and advancing the national economy. The JPSS is developed by the National Aeronautics and Space Administration (NASA) for the National Oceanic and Atmospheric Administration (NOAA), who is responsible for operation of JPSS. Three to five satellites are planned for the JPSS constellation of satellites. JPSS satellites will be flown, and the scientific data from JPSS will be processed, by the JPSS – Common Ground System (JPSS-CGS).
GEOMS – Generic Earth Observation Metadata Standard is a metadata standard used for archiving data from groundbased networks, like the Network for the Detection of Atmospheric Composition Change (NDACC), and for using this kind of data for the validation of NASA and ESA satellite data.
NOAA-21, designated JPSS-2 prior to launch, is the second of the United States National Oceanic and Atmospheric Administration (NOAA)'s latest generation of U.S. polar-orbiting, non-geosynchronous, environmental satellites called the Joint Polar Satellite System. NOAA-21 was launched on 10 November 2022 and joined NOAA-20 and Suomi NPP in the same orbit. Circling the Earth from pole-to-pole, it will cross the equator about 14 times daily, providing full global coverage twice a day. It was launched with LOFTID.
Anne Ritger Douglass is atmospheric physicist known for her research on chlorinated compounds and the ozone layer.