Editing Deep Space Climate Observatory

{{Short description|American solar research spacecraft}}
{{Use American English|date=February 2021}}
{{Use dmy dates|date=February 2021}}
{{Infobox spaceflight
| name              = Deep Space Climate Observatory
| names_list        = DSCOVR<br/>Triana<br/>AlGoreSat
| image             = DSCOVR spacecraft model.png
| image_caption     = An artist's rendering of DSCOVR satellite
| image_size        = 300px

| mission_type      = [[Space weather]]
| operator          = [[NASA]]{{\}}[[National Oceanic and Atmospheric Administration|NOAA]]
| COSPAR_ID         = 2015-007A
| SATCAT            = 40390
| website           = {{URL|www.nesdis.noaa.gov/dscovr}}
| mission_duration  = 5 years (planned) <ref name="dscovr-infosheet"/><br/>{{time interval|11 February 2015 23:03:02|show=ymd|sep=,}} (elapsed)

| spacecraft        = 
| spacecraft_type   = 
| spacecraft_bus    = [[Explorers Program|SMEX-Lite]]
| manufacturer      = [[Goddard Space Flight Center]]
| launch_mass       = {{cvt|570|kg}} <ref name="dscovr-faq"/>
| dimensions        = Undeployed: {{cvt|1.4|xx|1.8|m}}
| power             = 600 watts

| launch_date       = 11 February 2015, 23:03:42 [[Coordinated Universal Time|UTC]]
| launch_rocket     = [[Falcon 9 v1.1]]
| launch_site       = [[Cape Canaveral Space Force Station|Cape Canaveral]], [[Cape Canaveral Space Launch Complex 40|SLC-40]]
| launch_contractor = [[SpaceX]]

| entered_service   = 8 June 2015
| last_contact      = 
| decay             =

| orbit_reference   = [[Heliocentric orbit]]<ref name="dscovr-infosheet"/>
| orbit_regime      = Sun-Earth [[Lagrange point]] L1
| orbit_periapsis   = 
| orbit_apoapsis    = 
| orbit_inclination = 
| orbit_period      = 
| apsis             = gee

| instruments_list = {{Infobox spaceflight/Instruments
  |acronym1 = PlasMag | name1 = Plasma-Magnetometer
  |acronym2 = NISTAR  | name2 = National Institute of Standards and Technology Advanced Radiometer
  |acronym3 = EPIC    | name3 = Earth Polychromatic Imaging Camera
  |acronym4 = ES      | name4 = Electron Spectrometer
  |acronym5 = PHA     | name5 = Pulse Height Analyzer
}}

| insignia          = DSCOVR Logo (transparent bg).png
| insignia_caption  = DSCOVR logo
| insignia_size     = 250px

| programme         = Space Weather program
| previous_mission  = 
| next_mission      = [[Space Weather Follow On-Lagrange 1]]
}}

'''Deep Space Climate Observatory''' ('''DSCOVR'''; formerly known as '''Triana''', unofficially known as '''GoreSat'''<ref name="airspace201408">{{cite news|url=http://www.airspacemag.com/space/al-gores-satellite-180952132/|title=Al Gore's Satellite|magazine=Air & Space/Smithsonian|first=Craig|last=Mellow|date=August 2014|access-date=December 12, 2014}}</ref>) is a [[National Oceanic and Atmospheric Administration]] (NOAA) [[space weather]], [[space climate]], and [[Earth observation satellite]]. It was launched by [[SpaceX]] on a [[Falcon 9 v1.1]] [[launch vehicle]] on 11 February 2015, from [[Cape Canaveral Space Force Station|Cape Canaveral]].<ref>{{cite news|url=http://www.nbcnews.com/science/space/spacex-scrubs-falcon-9s-dscovr-launch-again-due-winds-n303966|title=SpaceX Scrubs Falcon 9's DSCOVR Launch (Again) Due to Winds|work=NBC News|first=Alan|last=Boyle|date=February 10, 2015|access-date=February 15, 2015}}</ref> This is NOAA's first operational deep space satellite and became its primary system of warning [[Earth]] in the event of [[Solar storm|solar magnetic storms]].<ref name="dscovr-completes">{{cite web|url=http://www.nesdis.noaa.gov/DSCOVR/|title=DSCOVR completes its first year in deep space!|publisher=NOAA|date=March 7, 2016|access-date=March 12, 2019}} {{PD-notice}}</ref>

DSCOVR was originally proposed as an Earth observation spacecraft positioned at the [[Earth's orbit|Sun-Earth]] {{L1}} [[Lagrange 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 the [[United 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 of [[coronal mass ejection]]s while still providing Earth observation and climate monitoring. It launched aboard a [[SpaceX]] [[Falcon 9]] launch vehicle on 11 February 2015, and reached {{L1}} on 8 June 2015, joining the [[List of objects at Lagrange points|list of objects orbiting at Lagrange points]].

NOAA operates DSCOVR from its [https://www.ospo.noaa.gov/ Satellite and Product Operations Facility] in [[Suitland, Maryland]]. The acquired space data that allows for accurate weather forecasts are carried out in the [[Space Weather Prediction Center]] in [[Boulder, Colorado]]. Archival records are held by the [[National Centers for Environmental Information]], and processing of Earth sensor data is carried out by [[NASA]].<ref name="dscovr-infosheet"/>

== History ==
[[Image:Dscovr.jpg|thumb|upright=1.0|left|Deep Space Climate Observatory (DSCOVR)]]

DSCOVR began as a proposal in 1998 by then-[[Vice President of the United States|Vice President]] [[Al Gore]] for the purpose of whole-Earth observation at the Sun-Earth {{L1}} [[Lagrange point]], {{cvt|1.5|e6km}} from Earth.<ref name="airspace201408"/><ref name="popsci20110407">{{cite news|url=https://www.popsci.com/technology/article/2011-03/lost-satellite/|title=Who killed the Deep Space Climate Observatory?|publisher=Popular Science|first=Bill|last=Donahue|date=April 7, 2011|access-date=December 12, 2014}}</ref> Originally known as Triana, named after [[Rodrigo de Triana]], the first of [[Christopher Columbus|Columbus]]'s crew to sight land in the [[Americas]], 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 influential [[The Blue Marble|''Blue Marble'']] photograph that was taken by [[Apollo 17]].<ref>{{cite news|url=https://www.nytimes.com/1999/06/01/science/politics-keeps-a-satellite-earthbound.html|title=Politics Keeps a Satellite Earthbound|newspaper=The New York Times|first=Warren|last=Leary |date=June 1, 1999|access-date=July 24, 2009}}</ref> In addition to an imaging camera, a [[radiometer]] 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 of [[global 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 of [[Ultraviolet|UV]] light reaching the surface through the [[ozone layer]].

In 1999, NASA's [[NASA Office of Inspector General|Inspector 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".<ref>{{cite web|url=http://oig.nasa.gov/old/inspections_assessments/g-99-013.pdf|title=Assessment of the Triana Mission, G-99-013, Final Reportwork=Office of Inspector General|publisher=NASA|date=September 10, 1999|access-date=February 7, 2009|url-status=dead|archive-url=https://web.archive.org/web/20090320171922/http://oig.nasa.gov/old/inspections_assessments/g-99-013.pdf|archive-date=March 20, 2009}} {{PD-notice}}</ref> Members of the [[United States Congress|U.S. Congress]] asked the [[National Academy of Sciences]] whether the project was worthwhile. The resulting report, released March 2000, stated that the mission was "strong and scientifically vital".<ref name="NASA-Triana">{{cite news|url=http://earthobservatory.nasa.gov/Newsroom/MediaAlerts/2000/200003081676.html |title=NASA's Triana Mission Scientific Evaluation Completed|work=Earth Observatory|publisher=NASA|date=March 8, 2000|access-date=February 3, 2008|url-status=dead |archive-url=https://web.archive.org/web/20081011010504/http://earthobservatory.nasa.gov/Newsroom/MediaAlerts/2000/200003081676.html|archive-date=October 11, 2008}} {{PD-notice}}</ref>

The [[Presidency of George W. Bush|Bush administration]] put the project on hold shortly after George W. Bush's inauguration in January 2001.<ref name="popsci20110407"/> Triana was removed from its original launch opportunity on [[STS-107]] (the [[Space Shuttle Columbia disaster|ill-fated ''Columbia'' mission]] in 2003).<ref name="airspace201408"/> The US$150 million <ref name="airspace201408"/> spacecraft was placed into [[tank blanketing|nitrogen blanketed]] storage at [[Goddard Space Flight Center]] in November 2001 and remained there for the duration of the Bush administration.<ref name="sfnow20090302">{{cite news|url=http://spaceflightnow.com/news/n0903/01dscovr/|title=Mothballed satellite sits in warehouse, waits for new life|work=Spaceflight Now|first=Stephen|last=Clark|date=March 2, 2009}}</ref> NASA renamed the spacecraft Deep Space Climate Observatory (DSCOVR) in 2003 in an attempt to regain support for the project,<ref name="airspace201408"/> but the mission was formally terminated by NASA in 2005.<ref name="sfnow20110221">{{cite news|url=http://spaceflightnow.com/news/n1102/21dscovr/|title=NOAA taps DSCOVR satellite for space weather mission|work=Spaceflight Now|first=Stephen|last=Clark|date=February 21, 2011|archive-url=https://web.archive.org/web/20110224195356/http://www.spaceflightnow.com/news/n1102/21dscovr/|archive-date=February 24, 2011}}</ref>

In November 2008, funded by [[National Oceanic and Atmospheric Administration]] (NOAA) and the [[United States Air Force|U.S. Air Force]], the spacecraft was removed from storage and underwent testing to determine its viability for launch.<ref name="Siddiqi2018">{{cite book|url=https://www.nasa.gov/sites/default/files/atoms/files/beyond-earth-tagged.pdf|title=Beyond Earth: A Chronicle od Deep Space Exploration, 1958-2016|publisher=NASA|first=Asif A.|last=Siddiqi|page=303|date=2018|isbn=978-1-62683-043-1|lccn=2017058675}} {{PD-notice}}</ref><ref name="dscovr-revived">{{cite web |url=http://lssp.gsfc.nasa.gov/news/about_Triana_DSCOVR_Spacecraft_Successfully_Revived_from_Mothballs.html|title=Triana/DSCOVR Spacecraft Successfully Revived from Mothballs|publisher=NASA|date=February 15, 2009|access-date=September 7, 2009|archive-url=https://web.archive.org/web/20090612134408/http://lssp.gsfc.nasa.gov/news/about_Triana_DSCOVR_Spacecraft_Successfully_Revived_from_Mothballs.html|archive-date=June 12, 2009}} {{PD-notice}}</ref> After the [[Presidency of Barack Obama|Obama administration]] took presidency in 2009, that year's budget included US$9 million marked for refurbishment and readiness of the spacecraft,<ref name="popsci20110406">{{cite news|url=https://www.popsci.com/technology/article/2011-03/lost-satellite/|title=Who Killed The Deep Space Climate Observatory?|publisher=Popular Science|first=Bill |last=Donahue|date=April 6, 2011|access-date=September 24, 2019}}</ref> resulting in NASA refurbishing the EPIC instrument and recalibrating the NISTAR instrument.<ref name="Smith2011">{{cite conference|title=Earth Science Instrument Refurbishment, Testing and Recalibration for the Deep Space Climate Observatory (DSCOVR)|conference=American Geophysical Union Fall Meeting 2011|first1=R. C.|last1=Smith|first2=S. R.|last2=Lorentz|first3=J. |last3=Mobilia|first4=K.|last4=Sawyer|first5=E.|last5=Hertzberg|first6=H.|last6=Demroff|first7=J. P.|last7=Rice|journal=AGU Fall Meeting Abstracts|display-authors=1|date=December 2011|volume=2011|pages=A43G–03|bibcode=2011AGUFM.A43G..03S}}</ref> [[Al Gore]] used part of his book ''[[Our Choice]]'' (2009) as an attempt to revive debate on the DSCOVR payload. The book mentions legislative efforts by senators [[Barbara Mikulski]] and [[Bill Nelson]] to get the spacecraft launched.<ref>{{cite book|url=https://archive.org/details/ourchoiceplantos00gore|chapter=Chapter 17|title=Our Choice|publisher=Rodale|first=Al|last=Gore|date=2009|isbn=978-1-59486-734-7|url-access=registration}}</ref> In February 2011, the Obama administration attempted to secure funding to re-purpose the DSCOVR spacecraft as a solar observatory to replace the aging [[Advanced Composition Explorer]] (ACE) spacecraft, and requested US$47.3 million in the 2012 fiscal budget toward this purpose.<ref name="sfnow20110221"/> Part of this funding was to allow the [[United States Naval Research Laboratory|Naval 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.<ref name="dscovr-infosheet"/><ref name="sfnow20110221"/> NOAA allocated US$2 million in its 2011 budget to initiate the refurbishment effort, and increased funding to US$29.8 million in 2012.<ref name="airspace201408"/>

In 2012, the Air Force allocated US$134.5 million to procure a launch vehicle and fund launch operations, both of which were awarded to [[SpaceX]] for their [[Falcon 9]] rocket.<ref name="airspace201408"/><ref>{{cite press release|url=https://www.spacex.com/press/2012/12/19/spacex-awarded-two-eelv-class-missions-united-states-air-force|title=Spacex awarded two EELV-class missions from the United States Air Force |publisher=SpaceX|date=December 5, 2012|access-date=December 12, 2014}}</ref> In September 2013, NASA cleared DSCOVR to proceed to the implementation phase targeting an early 2015 launch,<ref>{{cite web |url=http://www.nasa.gov/content/goddard/dscovr-mission-moves-forward-to-2015-launch/|title=DSCOVR Mission Moves Forward to 2015 Launch|publisher=NASA/NOAA|first=John|last=Leslie|date=September 10, 2013}} {{PD-notice}}</ref> which ultimately took place on 11 February 2015.<ref name="Siddiqi2018"/> NASA's [[Goddard 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.<ref>{{cite news |url=http://www.bbc.com/culture/story/20170120-film-review-is-al-gores-an-inconvenient-sequel-worthwhile|title=Film review: Is Al Gore's An Inconvenient Sequel worthwhile?|publisher=BBC|first=Sam|last=Adams |date=January 20, 2017|access-date=May 30, 2018}}</ref>

== Spacecraft ==
[[Image:Deep Space Climate Observatory spacecraft diagram.jpg|thumb|upright=1.3|right|Diagram of DSCOVR]]

DSCOVR is built on the [[Explorers Program|SMEX-Lite]] spacecraft [[Satellite bus|bus]] and has a launch mass of approximately {{cvt|570|kg}}. 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.<ref name=noaa_spacecraft>{{cite web|url=http://www.nesdis.noaa.gov/DSCOVR/spacecraft.html|title=Spacecraft and Instruments|publisher=NOAA|access-date=February 10, 2015|url-status=dead |archive-url= https://web.archive.org/web/20150209074236/http://www.nesdis.noaa.gov/DSCOVR/spacecraft.html|archive-date= February 9, 2015}} {{PD-notice}}</ref>

The propulsion module had 145 kg of N<sub>2</sub>H<sub>4</sub> propellant.<ref>[https://www.thespacereview.com/article/4228/1 ''The little satellite that could'' 2021] See diagram.</ref> 

From its vantage point, DSCOVR monitors variable [[solar 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-Earth {{L1}} 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.<ref name="epicsite"/> DSCOVR takes full-Earth pictures about every two hours and is able to process them faster than other [[Earth observation satellite]]s.<ref>{{cite news|url=http://thinkprogress.org/climate/2015/02/04/3618338/sneak-peek-space-satellite-launch/|title=A Sneak Peek at NASA's New Satellite That has Been 16 Years in the Making| publisher= ThinkProgress| first=Ari| last=Phillips| date= February 4, 2015}}</ref>

The spacecraft is in a looping [[halo orbit]] around the Sun-Earth [[Lagrange point|Lagrange point L1]] in a six-month period, with a spacecraft–Earth–Sun angle varying from 4° to 15°.<ref name="dscovr-hosts">{{cite web |url= http://www.nesdis.noaa.gov/DSCOVR/|title=DSCOVR Mission Hosts Two NASA Earth-Observing Instruments| publisher= NOAA|date=October 21, 2014|access-date=February 9, 2015}} {{PD-notice}}</ref><ref>{{cite news |url= http://spaceflightnow.com/2015/06/08/dscovr-space-weather-sentinel-reaches-finish-line/|title=DSCOVR space weather sentinel reaches finish line |publisher= Spaceflight Now| first=Stephen| last= Clark| date=June 7, 2015}}</ref>

=== Instruments ===
==== PlasMag ====
The Plasma-[[Magnetometer]] (PlasMag) measures [[solar wind]] for [[space 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 reach {{L1}} about an hour before Earth, PlasMag can provide a warning of 15 to 60 minutes before a [[coronal 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".<ref name= "noaa_plasmag"/> It has three instruments:<ref name=noaa_plasmag>{{cite web|title=NOAA Satellite and Information Service: Deep Space Climate Observatory (DSCOVR): Plasma-Magnetometer (PlasMag) |url= http://www.nesdis.noaa.gov/DSCOVR/pdf/DSCOVR%20-%20PlasMag%20Instrument%20Info%20Sheet.pdf| publisher=NOAA|access-date= February 10, 2015|url-status= dead| archive-url= https://web.archive.org/web/20150210181113/http://www.nesdis.noaa.gov/DSCOVR/pdf/DSCOVR%20-%20PlasMag%20Instrument%20Info%20Sheet.pdf|archive-date=February 10, 2015}} {{PD-notice}}</ref>
* Magnetometer measures [[magnetic field]]
* [[Faraday cup]] measures positively [[charged particle]]s
* Electrostatic analyzer measures [[electron]]s

==== EPIC ====
[[File:Earth-DSCOVR-20150706-IFV.jpg|thumb|upright=1.3|right|The first EPIC image, released by NASA on 6 July 2015, shows the full sunlit Earth from {{cvt|1475207|km}} or nearly four [[lunar distance (astronomy)|lunar distances]] away, centered on the [[Americas]].<ref name= "nasa20150720">{{cite web |url= http://www.nasa.gov/image-feature/nasa-captures-epic-earth-image|title=NASA Captures "EPIC" Earth Image| publisher =NASA|first=Karen|last=Northon|date=July 20, 2015}} {{PD-notice}}</ref><ref>{{cite web|url=https://epic.gsfc.nasa.gov/?date=2015-07-06|title=DSCOVR: EPIC| publisher=NASA|date=July 6, 2015| access-date=February 26, 2018}} {{PD-notice}}</ref>]]

The Earth Polychromatic Imaging Camera (EPIC) takes images of the sunlit side of Earth for various Earth science monitoring purposes in ten different channels from [[ultraviolet]] to [[near-infrared]]. [[Ozone]] and [[aerosol]] levels are monitored along with cloud dynamics, properties of the land, and [[vegetation]].<ref name=noaa_epic>{{cite web |title= NOAA Satellite and Information Service: Deep Space Climate Observatory (DSCOVR): Enhanced Polychromatic Imaging Camera (EPIC) |url= http://www.nesdis.noaa.gov/DSCOVR/pdf/DSCOVR%20-%20EPIC%20Instrument%20Info%20Sheet.pdf| publisher=NOAA|date=January 14, 2015|access-date=February 10, 2015|url-status=dead|archive-url= https://web.archive.org/web/20150210181851/http://www.nesdis.noaa.gov/DSCOVR/pdf/DSCOVR%20-%20EPIC%20Instrument%20Info%20Sheet.pdf|archive-date=February 10, 2015}} {{PD-notice}}</ref>

EPIC has an aperture diameter of {{cvt|30.5|cm}}, a [[focal ratio]] of 9.38, a [[field of view]] of 0.61°, and an angular sampling resolution of 1.07 [[arcsecond]]s. Earth's [[apparent 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 779 [[nanometre|nm]]) 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 {{cvt|25|km|mi|abbr=on|disp=x|/pixel (|/pixel)}}.<ref name=noaa_epic/>

==== NISTAR ====
The National Institute of Standards and Technology Advanced Radiometer (NISTAR) was designed and built between 1999 and 2001 by NIST in Gaithersburg, MD and  [[Ball Aerospace & Technologies]] in [[Boulder, Colorado]]. NISTAR measures irradiance of the sunlit face of the Earth. This means that NISTAR measures if the [[atmosphere 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's [[radiation budget]] caused by natural and human activities.<ref name=noaa_nistar>{{cite web| title= NOAA Satellite and Information Service: Deep Space Climate Observatory (DSCOVR): National Institute of Standards and Technology Advanced Radiometer (NISTAR)|url=http://www.nesdis.noaa.gov/DSCOVR/pdf/DSCOVR%20-%20NISTAR%20Instrument%20Info%20Sheet.pdf| publisher=NOAA|access-date= February 10, 2015|url-status= dead |archive-url= https://web.archive.org/web/20150422070911/http://www.nesdis.noaa.gov/DSCOVR/pdf/DSCOVR%20-%20NISTAR%20Instrument%20Info%20Sheet.pdf|archive-date=April 22, 2015}} {{PD-notice}}</ref>

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.<ref>{{cite web |url= http://www.nasa.gov/content/goddard/noaas-dscovr-nistar-instrument-watches-earths-budget|title=NOAA's DSCOVR NISTAR Instrument Watches Earth's "Budget"|publisher=NASA|last=Jenner|first=Lynn|date=January 20, 2015|access-date=March 12, 2019}} {{PD-notice}}</ref> The radiometer measures in four channels:
* For total radiation in [[ultraviolet]], [[Visible spectrum|visible]] and [[infrared]] in the range 0.2–100&nbsp;μm
* For reflected solar radiation in the ultraviolet, visible and near-infrared in the range 0.2–4&nbsp;μm
* For reflected solar radiation in infrared in the range 0.7–4&nbsp;μm
* For calibration purposes in the range 0.3–1&nbsp;μm

== Launch ==
The DSCOVR launch was conducted by [[launch service provider|launch provider]] [[SpaceX]] using their [[Falcon 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 {{cvt|1.5|e6km}} away from Earth at the Sun-Earth L1 [[Lagrange point]].<ref name="directory.eoportal.org">{{cite web|url=https://directory.eoportal.org/web/eoportal/satellite-missions/d/dscovr#launch|title=DSCOVR - Satellite Missions|publisher=ESA|website=directory.eoportal.org |access-date=March 12, 2019}}</ref><ref name="noaa20150608">{{cite news|url=https://www.nasa.gov/feature/goddard/nation-s-first-operational-satellite-in-deep-space-reaches-final-orbit|title=NOAA's First Operational Satellite in Deep Space Reaches Final Orbit|publisher=NASA|date=June 8, 2015|access-date=May 1, 2019}} {{PD-notice}}</ref>

=== Launch attempt history ===
{{LaunchAttempt
<!-- use 24-hour times for sorting purposes, they will be displayed in 12-hour format by the template -->

| date1           = 8 February 2015, 23:10:00
| result1         = Scrubbed
| reason1         = Technical
| weathergo1      = >90
| decision_date1  =
| decision_clock1 = 02:40:00
| notes1          = [[Eastern Range|Range]] issues: tracking,<ref>{{cite news|url=http://www.waaytv.com/space_alabama/spacex-discovr-launch-scrubbed/article_2a75d112-afeb-11e4-bd09-e7da992d6b35.html|title=SpaceX DISCOVR launch scrubbed|publisher=WAAYTV|series=Space Alabama|first=Miriam|last=Cresswell|date=February 8, 2015|url-status=dead|archive-url=https://archive.today/20150211092953/http://www.waaytv.com/space_alabama/spacex-discovr-launch-scrubbed/article_2a75d112-afeb-11e4-bd09-e7da992d6b35.html|archive-date=February 11, 2015}}</ref> first-stage video transmitter issues noted

| date2          = 10 February 2015, 23:04:49
| result2        = Scrubbed
| reason2        = [[Launch weather|Weather]]
| notes2         = Upper-level winds at the launch pad exceeded {{convert|100|kn}} at {{cvt|7600|m}}
| weathergo2     = 80

| date3          = 11 February 2015, 23:03:42
| result3        = Success
| weathergo3     = >90
}}

== Operation ==
{{multiple image|align=right|direction=vertical
| header   = An animation of Deep Space Climate Observatory's trajectory
| image1   = Animation of Deep Space Climate Observatory trajectory.gif
| caption1 = An oblique view

| image2   = Animation of Deep Space Climate Observatory trajectory viewed from the Sun.gif
| caption2 = As viewed from the Sun:
| footer   = {{legend2|magenta|Deep Space Climate Observatory}}{{·}}{{legend2|RoyalBlue|[[Earth]]}}{{·}}{{legend2|Gold|[[Moon]]}}
}}

On 6 July 2015, DSCOVR returned its first publicly released view of the entire [[Earthlight (astronomy)|sunlit side]] of Earth from {{cvt|1475207|km}} away, taken by the EPIC instrument. EPIC provides a daily series of [[Earth observation|Earth 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.<ref name="nasa20150720"/>

DSCOVR was placed in operation at the L1 [[Lagrange point]] to monitor the [[Sun]], because the constant stream of particles from the Sun (the [[solar 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 and [[magnetic field]] from a [[coronal mass ejection]] (CME) reaches Earth and creates a [[geomagnetic 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 in [[geosynchronous orbit]] are at risk of unplanned disruptions without warnings from DSCOVR and other monitoring satellites at L1.<ref name="dscovr-about">{{cite web|url=http://www.nesdis.noaa.gov/DSCOVR/|title=DSCOVR: Deep Space Climate Observatory|publisher=NOAA|access-date=July 22, 2015}} {{PD-notice}}</ref>

On 16–17 July 2015, DSCOVR took a series of images showing the [[Moon]] during a [[transit (astronomy)|transit]] of Earth. The images were taken between 19:50 and 00:45 [[UTC]]. The animation was composed of [[monochrome]] images taken in different [[optical filter|color 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 Moon [[lunar phase|illuminated]] and will always see its [[far side of the Moon|far side]] when it passes in front of Earth.<ref name="sfnow20150805">{{cite news |url=http://spaceflightnow.com/2015/08/05/watch-the-moon-transit-the-earth/|title=Watch the moon transit the Earth|publisher=Spaceflight Now|first=Stephen|last=Clark|date=August 5, 2015}}</ref>

On 19 October 2015, NASA opened a new website to host near-live "[[Blue Marble]]" images taken by EPIC of Earth.<ref name="epicsite">{{cite web|url=https://epic.gsfc.nasa.gov/|title=DSCOVR: EPIC – Earth Polychromatic Imaging Camera|publisher=NASA|access-date=August 30, 2019}} {{PD-notice}}</ref> Twelve images are released each day, every two hours, showcasing Earth as [[Earth's rotation|it rotates]] on its axis.<ref name="epicimages">{{cite news|url=http://spaceflightnow.com/2015/10/19/nasa-to-post-new-blue-marble-pictures-every-day/|title=NASA to post new "blue marble" pictures every day|publisher=Spaceflight Now|first=Stephen|last=Clark|date=October 19, 2015}}</ref> The resolution of the images ranges from {{cvt|10|to|15|km|0|disp=x| per pixel (|/pixel)}}, and the short [[exposure time]]s renders points of starlight invisible.<ref name="epicimages"/>

On 27 June 2019, DSCOVR was put into [[safe mode (spacecraft)|safe mode]] due to an anomaly with the laser gyroscope of the Miniature Inertial Measurement Unit (MIMU), part of the spacecraft's [[Spacecraft attitude control|attitude control]] system.<ref>{{cite news|url=https://spacenews.com/dscovr-spacecraft-in-safe-mode/|title=DSCOVR spacecraft in safe mode|publisher=SpaceNews|last=Foust|first=Jeff|date=July 5, 2019}}</ref> Operators programmed a software patch that allows DSCOVR to operate without a laser gyroscope, using only the star tracker for angular rate information.<ref>{{cite news|title=Software fix planned to restore DSCOVR |url=https://spacenews.com/software-fix-planned-to-restore-dscovr/|access-date=3 March 2020|publisher=SpaceNews|date=1 October 2019}}</ref> DSCOVR came out of the safe hold on 2 March 2020, and resumed normal operations.<ref>{{cite news|title=DSCOVR back in operation|url=https://spacenews.com/dscovr-back-in-operation/|publisher=SpaceNews|date=3 March 2020}}</ref>

== Picture Sequences ==
{{multiple image|align=center|direction=horizontal|caption_align=center|total_width=800
 |image1=Dscovrepicmoontransitfull.gif|caption1=The Moon [[transit (astronomy)|transiting]] Earth, 16 July 2015. The [[far side of the Moon]] faces the camera.
 |image2=EpicEarth-Globespin-tilt-23.4.gif|caption2=The Earth depicted with its [[axial tilt|23.4° tilt]] (the cause of the [[season]]s) on [[#EPIC|EPIC]]{{'s}} 268th day of operation, 25 September 2015, a few days after the [[September equinox]].
 |image3=EpicEarth-Globespin(2016May29).gif|caption3=The [[Earth's rotation]] on 29 May 2016, a few weeks prior to the [[June solstice]], with the Northern Hemisphere tilted toward the Sun.
 |image4=An_EPIC_Eclipse.gif|caption4=From space, the Moon's shadow during the [[Solar eclipse of March 9, 2016|solar eclipse of 9 March 2016]] appears as a dark spot moving across the Earth.
}}

== See also ==
* [[Clouds and the Earth's Radiant Energy System]]
* [[STEREO]]
* [[Visual Monitoring Camera]]
* [[List of Falcon 9 and Falcon Heavy launches]]

{{Portal bar|Spaceflight|Astronomy|Solar System}}

== References ==
{{Reflist|30em|refs=

<ref name="dscovr-infosheet">{{cite web|url=https://www.nesdis.noaa.gov/sites/default/files/asset/document/dscovr_program_overview_info_sheet.pdf|title=NOAA Satellite and Information Service: Deep Space Climate Observatory (DSCOVR)|publisher=NOAA|access-date=September 24, 2019|archive-date=17 October 2020|archive-url=https://web.archive.org/web/20201017004955/https://www.nesdis.noaa.gov/sites/default/files/asset/document/dscovr_program_overview_info_sheet.pdf|url-status=dead}} {{PD-notice}}</ref>

<ref name="dscovr-faq">{{cite web|url=http://www.nesdis.noaa.gov/DSCOVR/pdf/DSCOVR-facts-Jan15.pdf|title=DSCOVR: Deep Space Climate Observatory|publisher=NOAA|date=January 2015|access-date=March 14, 2015|url-status=dead|archive-url=https://web.archive.org/web/20150402185249/http://www.nesdis.noaa.gov/DSCOVR/pdf/DSCOVR-facts-Jan15.pdf|archive-date=April 2, 2015}} {{PD-notice}}</ref>

}}

== External links ==
{{commons category|DSCOVR}}
* [https://www.nesdis.noaa.gov/DSCOVR/ DSCOVR website] at NOAA.gov
* [https://directory.eoportal.org/web/eoportal/satellite-missions/d/dscovr DSCOVR] at eoPortal.org
* [https://epic.gsfc.nasa.gov/ EPIC global images] at NASA.gov

=== Further reading ===
* {{cite book|url=http://www.nap.edu/catalog/9789/review-of-scientific-aspects-of-the-nasa-triana-mission-letter|title=Review of Scientific Aspects of the NASA Triana Mission: Letter Report|publisher=National Academies Press|location=Washington, D.C.|author=National Research Council|date=March 2000|doi=10.17226/9789|isbn=978-0-309-13169-8}}
* {{cite news|url=https://www.orlandosentinel.com/2001/07/15/politics-puts-100-million-satellite-on-ice/|title=Politics Puts $100 Million Satellite On Ice|newspaper=Orlando Sentinel|first=Melissa|last=Harris |date=July 15, 2001}}
* {{cite web|url=https://www.nytimes.com/2006/01/15/opinion/15park.html|title=Scorched Earth|series=Opinion Editorial|newspaper=The New York Times|first=Robert L.|last=Park|author-link=Robert L. Park |date=January 15, 2006}}
** Rebuttal: {{cite web|url=http://cstpr.colorado.edu/prometheus/archives/space_policy/000673repoliticizing_tria.html|title=Re-Politicizing Triana|publisher=Center for Science and Technology Policy Research |first=Roger A.|last=Pielke Jr.|author-link=Roger A. Pielke Jr.|date=January 15, 2006|access-date=March 15, 2015|archive-url=https://web.archive.org/web/20130614171807/http://cstpr.colorado.edu/prometheus/archives/space_policy/000673repoliticizing_tria.html|archive-date=June 14, 2013|url-status=dead}}
* {{cite news|url=http://www.popsci.com/technology/article/2011-03/lost-satellite|title=Who Killed The Deep Space Climate Observatory?|publisher=Popular Science|first=Bill|last=Donahue|date=April 6, 2011}}
* {{cite web|url=http://www.planetary.org/blogs/guest-blogs/2015/0728-dscovrs-halo.html|title=DSCOVR's Halo|publisher=The Planetary Society|first=Dave|last=Doody|date=July 28, 2015}}

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{{Al Gore}}

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[[Category:National Oceanic and Atmospheric Administration]]
[[Category:Earth observation satellites of the United States]]
[[Category:SpaceX payloads contracted by NASA]]
[[Category:Space probes launched in 2015]]
[[Category:Spacecraft using halo orbits]]
[[Category:Spacecraft using Lissajous orbits]]
[[Category:Earth imaging satellites]]
[[Category:Geospace monitoring satellites]]
[[Category:Artificial satellites at Earth-Sun Lagrange points]]