 An artist's rendering of DSCOVR satellite | |||||||||||||
| Names | DSCOVR Triana AlGoreSat | ||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Mission type | Space weather | ||||||||||||
| Operator | NASA / NOAA | ||||||||||||
| COSPAR ID | 2015-007A | ||||||||||||
| SATCATno. | 40390 | ||||||||||||
| Website | www | ||||||||||||
| Mission duration | 5 years (planned)[1] 10 years, 9 months, 11 days (elapsed) | ||||||||||||
| Spacecraft properties | |||||||||||||
| Bus | SMEX-Lite | ||||||||||||
| Manufacturer | Goddard Space Flight Center | ||||||||||||
| Launch mass | 570 kg (1,260 lb)[2] | ||||||||||||
| Dimensions | Undeployed: 1.4 × 1.8 m (4 ft 7 in × 5 ft 11 in) | ||||||||||||
| Power | 600 watts | ||||||||||||
| Start of mission | |||||||||||||
| Launch date | 11 February 2015, 23:03:42UTC | ||||||||||||
| Rocket | Falcon 9 v1.1 | ||||||||||||
| Launch site | Cape Canaveral,SLC-40 | ||||||||||||
| Contractor | SpaceX | ||||||||||||
| Entered service | 8 June 2015 | ||||||||||||
| Orbital parameters | |||||||||||||
| Reference system | Heliocentric orbit[1] | ||||||||||||
| Regime | Sun-EarthLagrange point L1 | ||||||||||||
| |||||||||||||
.png){kind=logo} DSCOVR logo Space Weather program | |||||||||||||
Deep Space Climate Observatory (DSCOVR; formerly known asTriana, unofficially known asGoreSat[3]) is aNational Oceanic and Atmospheric Administration (NOAA)space weather,space climate, andEarth observation satellite. It was launched bySpaceX on aFalcon 9 v1.1launch vehicle on 11 February 2015, fromCape Canaveral.[4] This is NOAA's first operational deep space satellite and became its primary system of warningEarth in the event ofsolar magnetic storms.[5]
DSCOVR was originally proposed as an Earth observation spacecraft positioned at theSun-EarthL1Lagrange point, providing live video of the sunlit side of the planet through the Internet as well as scientific instruments to study climate change. Political changes in theUnited States resulted in the mission's cancellation, and in 2001 the spacecraft was placed into storage.
Proponents of the mission continued to push for its reinstatement, and a change in presidential administration in 2009 resulted in DSCOVR being taken out of storage and refurbished, and its mission was refocused to solar observation and early warning ofcoronal mass ejections while still providing Earth observation and climate monitoring. It launched aboard aSpaceXFalcon 9 launch vehicle on 11 February 2015, and reachedL1 on 8 June 2015, joining thelist of objects orbiting at Lagrange points.
NOAA operates DSCOVR from itsSatellite and Product Operations Facility inSuitland, Maryland. The acquired space data that allows for accurate weather forecasts are carried out in theSpace Weather Prediction Center inBoulder, Colorado. Archival records are held by theNational Centers for Environmental Information, and processing of Earth sensor data is carried out byNASA.[1]
DSCOVR began as a proposal in 1998 by then-Vice PresidentAl Gore for the purpose of whole-Earth observation at the Sun-EarthL1Lagrange point, 1.5×10^6 km (0.93×10^6 mi) from Earth.[3][6] Originally known as Triana, named afterRodrigo de Triana, the first ofColumbus's crew to sight land in theAmericas, the spacecraft's original purpose was to provide a near-continuous view of the entire Earth and make that live image available via the Internet. Gore hoped not only to advance science with these images, but also to raise awareness of the Earth itself, updating the influentialBlue Marble photograph that was taken byApollo 17.[7] In addition to an imaging camera, aradiometer would take the first direct measurements of how much sunlight is reflected and emitted from the whole Earth (albedo). This data could constitute a barometer for the process ofglobal warming. The scientific goals expanded to measure the amount of solar energy reaching Earth, cloud patterns, weather systems, monitor the health of Earth's vegetation, and track the amount ofUV light reaching the surface through theozone layer.
In 1999, NASA'sInspector General reported that "the basic concept of the Triana mission was not peer reviewed", and "Triana's added science may not represent the best expenditure of NASA's limited science funding".[8] Members of theU.S. Congress asked theNational Academy of Sciences whether the project was worthwhile. The resulting report, released March 2000, stated that the mission was "strong and scientifically vital".[9]
TheBush administration put the project on hold shortly after George W. Bush's inauguration in January 2001.[6] Triana was removed from its original launch opportunity onSTS-107 (theill-fatedColumbia mission in 2003).[3] The US$150 million[3] spacecraft was placed intonitrogen blanketed storage atGoddard Space Flight Center in November 2001 and remained there for the duration of the Bush administration.[10] NASA renamed the spacecraft Deep Space Climate Observatory (DSCOVR) in 2003 in an attempt to regain support for the project,[3] but the mission was formally terminated by NASA in 2005.[11]
In November 2008, funded byNational Oceanic and Atmospheric Administration (NOAA) and theU.S. Air Force, the spacecraft was removed from storage and underwent testing to determine its viability for launch.[12][13] After theObama administration took presidency in 2009, that year's budget included US$9 million marked for refurbishment and readiness of the spacecraft,[14] resulting in NASA refurbishing the EPIC instrument and recalibrating the NISTAR instrument.[15]Al Gore used part of his bookOur Choice (2009) as an attempt to revive debate on the DSCOVR payload. The book mentions legislative efforts by senatorsBarbara Mikulski andBill Nelson to get the spacecraft launched.[16] In February 2011, the Obama administration attempted to secure funding to re-purpose the DSCOVR spacecraft as a solar observatory to replace the agingAdvanced Composition Explorer (ACE) spacecraft, and requested US$47.3 million in the 2012 fiscal budget toward this purpose.[11] Part of this funding was to allow theNaval Research Laboratory (NRL) to construct a coronal mass ejection imager for the spacecraft, but the time required would have delayed DSCOVR's launch and it was ultimately not included.[1][11] NOAA allocated US$2 million in its 2011 budget to initiate the refurbishment effort, and increased funding to US$29.8 million in 2012.[3]
In 2012, the Air Force allocated US$134.5 million to procure a launch vehicle and fund launch operations, both of which were awarded toSpaceX for theirFalcon 9 rocket.[3][17] In September 2013, NASA cleared DSCOVR to proceed to the implementation phase targeting an early 2015 launch,[18] which ultimately took place on 11 February 2015.[12] NASA'sGoddard Space Flight Center is providing management and systems engineering to the mission.
In the 2017 documentary,An Inconvenient Sequel: Truth to Power, Al Gore speaks of the history of the DSCOVR spacecraft and its relation to climate change.[19]
DSCOVR is built on theSMEX-Lite spacecraftbus and has a launch mass of approximately 570 kg (1,260 lb). The main science instrument sets are the Sun-observing Plasma Magnetometer (PlasMag) and the Earth-observing NIST Advanced Radiometer (NISTAR) and Earth Polychromatic Imaging Camera (EPIC). DSCOVR has two deployable solar arrays, a propulsion module, boom, and antenna.[20]
The propulsion module had 145 kg ofhydrazine propellant.[21]
From its vantage point, DSCOVR monitors variablesolar wind conditions, provides early warning of approaching coronal mass ejections and observes phenomena on Earth, including changes in ozone, aerosols, dust and volcanic ash, cloud height, vegetation cover and climate. At its Sun-EarthL1 location it has a continuous view of the Sun and of the sunlit side of the Earth. After the spacecraft arrived on-site and entered its operational phase, NASA began releasing near-real-time images of Earth through the EPIC instrument's website.[22] DSCOVR takes full-Earth pictures about every two hours and is able to process them faster than otherEarth observation satellites.[23]
The spacecraft is in a loopinghalo orbit around the Sun-EarthLagrange point L1 in a six-month period, with a spacecraft–Earth–Sun angle varying from 4° to 15°.[24][25]
The Plasma-Magnetometer (PlasMag) measuressolar wind forspace weather predictions. It can provide early warning detection of solar activity that could cause damage to existing satellite systems and ground infrastructure. Because solar particles reachL1 about an hour before Earth, PlasMag can provide a warning of 15 to 60 minutes before acoronal mass ejection (CME) arrives. It does this by measuring "the magnetic field and the velocity distribution functions of the electron, proton and alpha particles (helium nuclei) of solar wind".[26] It has three instruments:[26]
The Earth Polychromatic Imaging Camera (EPIC) takes images of the sunlit side of Earth for various Earth science monitoring purposes in ten different channels fromultraviolet tonear-infrared.Ozone andaerosol levels are monitored along with cloud dynamics, properties of the land, andvegetation.[29]
EPIC has an aperture diameter of 30.5 cm (12.0 in), afocal ratio of 9.38, afield of view of 0.61°, and an angular sampling resolution of 1.07arcseconds. Earth'sapparent diameter varies from 0.45° to 0.53° full width.Exposure time for each of the 10 narrowband channels (317, 325, 340, 388, 443, 552, 680, 688, 764, and 779nm) is about 40 ms. The camera produces 2048 × 2048 pixel images, but to increase the number of downloadable images to ten per hour the resolution is averaged to 1024 × 1024 on board. The final resolution is 25 km/pixel (16 mi/pixel).[29]
The National Institute of Standards and Technology Advanced Radiometer (NISTAR) was designed and built between 1999 and 2001 by NIST in Gaithersburg, MD andBall Aerospace & Technologies inBoulder, Colorado. NISTAR measures irradiance of the sunlit face of the Earth. This means that NISTAR measures if theatmosphere of Earth is taking in more or less solar energy than it is radiating back towards space. This data is to be used to study changes in Earth'sradiation budget caused by natural and human activities.[30]
Using NISTAR data, scientists can help determine the impact that humanity is having on the atmosphere of Earth and make the necessary changes to help balance the radiation budget.[31] The radiometer measures in four channels:
The DSCOVR launch was conducted bylaunch providerSpaceX using theirFalcon 9 v1.1 rocket. The launch of DSCOVR took place on 11 February 2015, following two scrubbed launches. It took DSCOVR 110 days from when it left Cape Canaveral Air Force Station (CCAFS),Florida, to reach its target destination 1.5×10^6 km (0.93×10^6 mi) away from Earth at the Sun-Earth L1Lagrange point.[32][33]
| Attempt | Planned | Result | Turnaround | Reason | Decision point | Weather go (%) | Notes |
|---|---|---|---|---|---|---|---|
| 1 | 8 Feb 2015, 11:10:00 pm | Scrubbed | — | Technical | (T02:40:00) | >90 | Range issues: tracking,[34] first-stage video transmitter issues noted |
| 2 | 10 Feb 2015, 11:04:49 pm | Scrubbed | 1 day 23 hours 55 minutes | Weather | 80 | Upper-level winds at the launch pad exceeded 100 knots (190 km/h; 120 mph) at 7,600 m (24,900 ft) | |
| 3 | 11 Feb 2015, 11:03:42 pm | Success | 0 days 23 hours 59 minutes | >90 |
On 6 July 2015, DSCOVR returned its first publicly released view of the entireearthlight side of Earth from 1,475,207 km (916,651 mi) away, taken by the EPIC instrument. EPIC provides a daily series ofEarth images, enabling the first-time study of daily variations over the entire globe. The images, available 12 to 36 hours after they are made, have been posted to a dedicated web page since September 2015.[27]
DSCOVR was placed in operation at the L1Lagrange point to monitor theSun, because the constant stream of particles from the Sun (thesolar wind) reaches L1 about 60 minutes before reaching Earth. DSCOVR will usually be able to provide a 15- to 60-minute warning before a surge of particles andmagnetic field from acoronal mass ejection (CME) reaches Earth and creates ageomagnetic storm. DSCOVR data will also be used to improve predictions of the impact locations of a geomagnetic storm to be able to take preventative action. Electronic technologies such as satellites ingeosynchronous orbit are at risk of unplanned disruptions without warnings from DSCOVR and other monitoring satellites at L1.[35]
On 16–17 July 2015, DSCOVR took a series of images showing theMoon during atransit of Earth. The images were taken between 19:50 and 00:45UTC. The animation was composed ofmonochrome images taken in differentcolor filters at 30-second intervals for each frame, resulting in a slight color fringing for the Moon in each finished frame. Due to its position at Sun–Earth L1, DSCOVR will always see the Moonilluminated and will always see itsfar side when it passes in front of Earth.[36]
On 19 October 2015, NASA opened a new website to host near-live "Blue Marble" images taken by EPIC of Earth.[22] Twelve images are released each day, every two hours, showcasing Earth asit rotates on its axis.[37] The resolution of the images ranges from 10 to 15 km per pixel (6 to 9 mi/pixel), and the shortexposure times renders points of starlight invisible.[37]
On 27 June 2019, DSCOVR was put intosafe mode due to an anomaly with the laser gyroscope of the Miniature Inertial Measurement Unit (MIMU), part of the spacecraft'sattitude control system.[38] Operators programmed a software patch that allows DSCOVR to operate without a laser gyroscope, using only the star tracker for angular rate information.[39] DSCOVR came out of the safe hold on 2 March 2020, and resumed normal operations.[40]
On 16 July 2025, DSCOVR suffered a software bus anomaly, which put it offline without an estimated date for recovery.[41] On 12 October 2025, the amateur-operatedDwingeloo Radio Observatory received signals again.,[42] after which AMSAT-DL successfully downloaded EPIC images on 23 October 2025.[43]
.gif)
This article incorporates text from this source, which is in thepublic domain. This article incorporates text from this source, which is in thepublic domain. This article incorporates text from this source, which is in thepublic domain. This article incorporates text from this source, which is in thepublic domain. This article incorporates text from this source, which is in thepublic domain. This article incorporates text from this source, which is in thepublic domain. This article incorporates text from this source, which is in thepublic domain. This article incorporates text from this source, which is in thepublic domain. This article incorporates text from this source, which is in thepublic domain. This article incorporates text from this source, which is in thepublic domain. This article incorporates text from this source, which is in thepublic domain. This article incorporates text from this source, which is in thepublic domain. This article incorporates text from this source, which is in thepublic domain. This article incorporates text from this source, which is in thepublic domain. This article incorporates text from this source, which is in thepublic domain. This article incorporates text from this source, which is in thepublic domain. This article incorporates text from this source, which is in thepublic domain. This article incorporates text from this source, which is in thepublic domain. This article incorporates text from this source, which is in thepublic domain.
| |||||||||
| Politics |
| ||||||||
| Electoral History |
| ||||||||
| Environment | |||||||||
| Technology | |||||||||
| Recognition | |||||||||
| Books | |||||||||
| Family |
| ||||||||
