Skip to Main Content


The National Aeronautics and Space Act of 1958 (Space Act) established NASA as an aerospace research and development agency that sponsors and conducts flight missions to obtain data in furtherance of its objectives. In NASA's Science Mission Directorate (SMD), flight missions range from suborbital projects—including balloons, sounding rockets, and airplanes—to interplanetary probes and flagship observatories. All investigations and missions selected and flown must respond to Agency goals and strategic objectives.

Mission opportunities are open to all proposers, within fixed rules, via public announcement, and selections are based primarily on scientific and technical merit as evaluated by independent peer review. Foreign partners are frequent and valued participants in joint missions. The partnerships are generally conducted on a cooperative, no-exchange-of-funds basis. NASA also works closely with a number of other Federal agencies to implement and support our flight missions. To learn more about mission planning and development, see section 3.3 of the Science Plan for NASA's Science Mission Directorate 2007 - 2016 (PDF 5.1 MB).

This page provides access to all SMD missions, with several options for viewing. Click on the column headers below to change your view. The "All" tab will provide you with a complete listing that can be sorted to suit your interests.

*Sort missions by clicking the column headers.

DivisionNameLaunch DatePhase
Heliophysics ACE
Advanced Composition Explorer (ACE) observes particles of solar, interplanetary, interstellar, and galactic origins, spanning the energy range from solar wind ions to galactic cosmic ray nuclei. This mission is part of SMD's Explorers Program. This mission is part of SMD's ...
19970825 August 25, 1997 3Operating
Heliophysics AIM
Aeronomy of Ice in the Mesosphere (AIM) is a mission to determine the causes of the highest altitude clouds in the Earth's atmosphere. The number of clouds in the middle atmosphere (mesosphere) over the Earth's poles has been increasing over ...
20070425 April 25, 2007 3Operating
Heliophysics BARREL
The Balloon Array for Radiation-belt Relativistic Electron Losses mission is a balloon-based Mission of Opportunity to augment the measurements of NASA's RBSP spacecraft. This mission is part of SMD's LWS program.
Heliophysics CINDI/CNOFS
The Coupled Ion-Neutral Dynamics Investigations (CINDI) is a mission to understand the dynamics of the Earth's ionosphere. CINDI will provide two instruments for the Communication/Navigation Outage Forecast System (C/NOFS) satellite, a project of the United States Air Force. This mission ...
20080416 April 16, 2008 3Operating
Heliophysics Cluster-II
Cluster is a European Space Agency program with major NASA involvement. The 4 Cluster spacecraft are providing a detailed three-dimensional map of the magnetosphere, with surprising results. This mission is part of SMD's Heliophysics Research program.
20000716 July 16, 2000 3Operating
Heliophysics DSCOVR
The Deep Space Climate Observatory (DSCOVR) mission is a multi-agency (NOAA, United States Air Force [USAF], and NASA) mission with the primary goal of making unique space weather measurements from the Lagrange point L1.
20150211 February 2015 3Operating
Heliophysics Equator-S
Equator-S was a German Space Agency project, with contributions from ESA and NASA, related to the International Solar-Terrestrial Physics program. The mission provided high-resolution plasma, magnetic, and electric field measurements in several regions not adequately covered by any of the ...
19971202 December 02, 1997 4Past
Heliophysics FAST
Fast Auroral Snapshot Explorer (FAST) studies the detailed plasma physics of the Earth's auroral regions. Ground support campaigns coordinate satellite measurements with ground observations of the Aurora Borealis, commonly referred to as the Northern Lights. The science instruments on board ...
19960821 August 21, 1996 4Past
Heliophysics Geotail
The GEOTAIL mission is a collaborative project undertaken by the Japanese Institute of Space and Astronautical Science (ISAS) and NASA. Its primary objective is to study the tail of the Earth's magnetosphere. The information gathered is allowing scientists to model ...
19920724 July 24, 1992 3Operating
Heliophysics GOLD
The Global-scale Observations of the Limb and Disk (GOLD) mission of opportunity will fly an ultraviolet (UV) imaging spectrograph on a geostationary satellite to measure densities and temperatures in Earth's thermosphere and ionosphere.
20180401 April 2018
Heliophysics Hinode (Solar-B)
Hinode (formerly known as Solar-B) is a Japanese ISAS mission proposed as a follow-on to the highly successful Japan/US/UK Yohkoh (Solar-A) collaboration. The mission consists of a coordinated set of optical, EUV and X-ray instruments that are studying the interaction ...
20060923 September 23, 2006 3Operating
Heliophysics IBEX
IBEX will be the first mission designed to detect the edge of the Solar System. As the solar wind from the sun flows out beyond Pluto, it collides with the material between the stars, forming a shock front. This mission ...
20081019 October 19, 2008 3Operating
Heliophysics ICON
ICON is a single spacecraft mission dedicated to understanding neutral-ion coupling in the Earth’s upper atmosphere (thermosphere). It will resolve both long-standing and newly emerging questions about the mechanisms that control the daily development of plasma in Earth’s space environment.
20171001 October 2017 2Development
Heliophysics IMAGE
IMAGE studied the global response of the magnetosphere to changes in the solar wind. Major changes occur to the configuration of the magnetosphere as a result of changes in and on the Sun, which in turn change the solar wind.
20000325 March 25, 2000 4Past
Heliophysics IMP-8
IMP 8 has deepened understanding of the space environment near Earth in many ways. Observations from IMP 8 provided insight into plasma physics, the Earth's magnetic field, the structure of the solar wind and the nature of cosmic rays.
19731026 October 26, 1973 4Past
Heliophysics IRIS
The primary goal of the Interface Region Imaging Spectrograph (IRIS) explorer is to understand how the solar atmosphere is energized. The IRIS investigation combines advanced numerical modeling with a high resolution UV imaging spectrograph.
20130627 June 27, 2013 3Operating
Heliophysics ISEE
The ISEE (International Sun-Earth Explorer) program was an international cooperative program between NASA and ESA to study the interaction of the solar wind with the Earth's magnetosphere.
19780812 August 12, 1978 4Past
Heliophysics MMS
The Magnetospheric Multiscale mission will determine the small-scale basic plasma processes which transport, accelerate and energize plasmas in thin boundary and current layers – and which control the structure and dynamics of the Earth's magnetosphere. MMS will for the first ...
20150312 March 2015 3Operating
Heliophysics Polar
Polar is the second of two NASA spacecraft in the Global Geospace Science (GGS) initiative and part of the ISTP Project. GGS is designed to improve greatly the understanding of the flow of energy, mass and momentum in the solar-terrestrial ...
19960224 February 24, 1996 4Past
Heliophysics RHESSI
Reuven Ramaty High Energy Solar Spectroscope Imager (RHESSI) studies solar flares in X-rays and gamma-rays. It explores the basic physics of particle acceleration and explosive energy release in these energetic events in the Sun's atmosphere. This is accomplished by imaging ...
20020205 February 05, 2002 3Operating
Heliophysics SAMPEX
The Solar Anomalous and Magnetospheric Particle Explorer was investigating the composition of local interstellar matter and solar material and the transport of magnetospheric charged particles into the Earth's atmosphere.
19920703 July 03, 1992 4Past
Heliophysics SNOE
SNOE ("snowy") was a small satellite investigating the effects of energy from the Sun and from the magnetosphere on the density of nitric oxide in the Earth's upper atmosphere.
19980226 February 26, 1998 4Past
Heliophysics SOHO
Solar and Heliospheric Observatory (SOHO) is a solar observatory studying the structure, chemical composition, and dynamics of the solar interior. SOHO a joint venture of the European Space Agency and NASA. This mission is part of SMD's Heliophysics Research program.
19951202 December 02, 1995 3Operating
Heliophysics Solar Dynamics Observatory (SDO)
The Solar Dynamics Observatory (SDO) is the first mission and crown jewel in a fleet of NASA missions to study our sun. The mission is the cornerstone of a NASA science program called Living With a Star (LWS). The goal ...
20100211 February 11, 2010 3Operating
Heliophysics Solar Orbiter
Solar Orbiter is a European Space Agency (ESA) mission to study the Sun from a distance closer than any spacecraft previously has, and will provide images and measurements in unprecedented resolution and detail. This mission is part of SMD's LWS ...
20181017 October 2018 2Development
Heliophysics Solar Probe Plus
Solar Probe Plus will be a historic mission, flying into one of the last unexplored regions of the solar system, the Sun’s atmosphere or corona, for the first time. This mission is part of SMD's LWS Program.
20180708 July 2018 2Development
Heliophysics Space Environment Testbeds
The Space Environment Testbeds (SET) Project performs flight and ground investigations to understand how the Sun/Earth interactions affect humanity.
20160601 June 2016 2Development
Heliophysics Spartan 201
Spartan was a small, Shuttle-launched and retrieved satellite. Spartan 201, whose mission was to study the Sun, has a science payload consisting of two telescopes: the Ultraviolet Coronal Spectrometer (UVCS) and the White Light Coronagraph (WLC). Spartan 201 was launched ...
19940913 September 13, 1994 4Past
Heliophysics ST5
Space Technology 5 (ST5) flight tested its miniaturized satellites and innovative technologies in the harsh environment of Earth's magnetosphere.
20060322 March 22, 2006 4Past
Heliophysics STEREO
The goal of STEREO is to understand the origin the Sun's coronal mass ejections (CMEs) and their consequences for Earth. The mission consists of two spacecraft, one leading and the other lagging Earth in its orbit. The spacecraft carries instrumentation ...
20061025 October 25, 2006 3Operating
Heliophysics THEMIS
Time History of Events and Macroscale Interactions during Substorms (THEMIS) is a study of the onset of magnetic storms within the tail of the Earth's magnetosphere. THEMIS will fly five microsatellite probes through different regions of the magnetosphere and observe ...
20070217 February 17, 2007 3Operating
Heliophysics TIMED
Thermosphere, Ionosphere, Mesosphere Energetics and Dynamics (TIMED) explores the energy transfer into and out of the Mesosphere and Lower Thermosphere/Ionosphere (MLTI) region of the Earth's atmosphere. This mission is part of SMD's Solar Terrestrial Probes Program.
20011207 December 07, 2001 3Operating
Heliophysics TRACE
Transition Region and Coronal Explorer (TRACE) observed the effects of the emergence of magnetic flux from deep inside the Sun to the outer corona with high spatial and temporal resolution. This mission was part of SMD's Heliophysics Explorers program. This ...
19980401 April 01, 1998 4Past
Heliophysics TSS
The Tethered Satellite System (TSS) consists of a satellite, a conducting tether, and a tether deployment/retrieval system to be flown on the Space Shuttle.
19920626 June 26, 1992 4Past
Heliophysics TWINS A & B
TWINS will provide stereo imaging of the Earth's magnetosphere, the region surrounding the planet controlled by its magnetic field and containing the Van Allen radiation belts and other energetic charged particles. This mission is part of SMD's Explorers Program. This ...
20080313 March 13, 2008 3Operating
Heliophysics Ulysses
The Ulysses Mission was the first spacecraft to explore interplanetary space at high solar latitudes, orbiting the Sun nearly perpendicular to the plane in which the planets orbit. This mission was part of SMD's Heliophysics Research program.
19901006 October 06, 1990 4Past
Heliophysics Van Allen Probes
The Van Allen Probes are designed to help us understand the Sun’s influence on Near-Earth space by studying the Earth’s radiation belts on various scales of space and time.
20120830 August 2012 3Operating
Heliophysics Voyager
The twin Voyager 1 and 2 spacecraft continue exploring where nothing from Earth has flown before. In the 25th year after their 1977 launches, they each are much farther away from Earth and the Sun than Pluto is and approaching ...
19770905 September 05, 1977 3Operating
Heliophysics Wind
Wind studies the solar wind and its impact on the near-Earth environment. This mission is part of SMD's Heliophysics Research program.
19941101 November 01, 1994 3Operating
Heliophysics Yohkoh
Yohkoh, an observatory for studying X-rays and gamma-rays from the Sun, is a project of the Institute for Space and Astronautical Sciences, Japan.
19910830 August 30, 1991 4Past