Exploring Our Sun

Our Sun is a sphere of hot plasma with internal convective motion that generates a magnetic field via a dynamo process. It is the most important source of energy for life on Earth.

It has a diameter of approximately 1.39 million kilometers, or 109 times that of Earth. Its mass is about 330,000 times that of Earth and accounts for about 99.86% of the total mass of the Solar System.

Our Sun consists of 73% hydrogen, 25% helium and 2% of heavier elements, including oxygen, carbon, neon, and iron.

Based on its spectral class our Sun is a G-type main-sequence star (G2V) and informally referred to as a yellow dwarf even though its light is closer to white than yellow.

Our Sun formed approximately 4.6 billion years ago from the gravitational collapse of matter within a region of a large molecular cloud. Most of this matter gathered in the center and the rest flattened into the orbiting disk of our Solar System.

The central mass then became so hot and dense that it eventually initiated nuclear fusion in its core. It is thought that almost all stars form by this process. It is thought that almost all stars form by this process.

Our Sun currently fuses about 600 million tons of hydrogen into helium every second, converting 4 million tons of matter into energy every second as a result. This energy is the source of the Sun's light and heat.

Reference: Wikipedia - Sun

Spacecraft Missions

A spacecraft mission to explore our Solar System starts with its launch from earth using a rocket launcher. The spacecraft then uses its own engines to reach its objective and carry out its mission. Some missions have multiple objectives.

The duration of a mission varies, depending on the craft used and purpose of the mission.

The table below is an overview or all the successful spacecraft missions, to date, used to study our Sun. It only includes spacecraft that left Earth orbit to perform their mission.

Point to ℹ for table information. (Table head remains visible while scrolling)
Select the Spacecraft name or Target for more information.

Img ℹ Reference number for image gallery below.	Spacecraft ℹ Used to perform the mission.	Launcher ℹ Used to carry the spacecraft out of the Earth's atmosphere.	Country ℹ Main country which developed the mission.	Year ℹ Year the spacecraft was launched and when the mission came to an end.		Mission ℹ Main mission objectives or events.	Notes ℹ Additional information.
				Launch	End

1	Pioneer 5	Thor Able	U.S.	1960	1960	Used to investigate interplanetary space between the orbits of Earth and Venus. It Measured magnetic fields, solar flare particles, and ionization in space.	A spin-stabilized space probe in the NASA Pioneer program.
2	Pioneer 6	Thor Delta E	U.S.	1965	2000	A network of solar-orbiting "space weather" monitors, observing solar wind cosmic rays, and magnetic fields.	A series of spin-stabilized, solar cell and battery powered satellites designed to obtain measurements from widely separated points in space. These were part of the NASA Pioneer program.
3	Pioneer 7	Thor Delta E1		1966	1995
4	Pioneer 8			1967	2001
5	Pioneer 9			1968	1983
6	Helios A	Titan IIIE	Germany, U.S.	1974	1982	Observations of solar wind, magnetic and electric fields, cosmic rays and cosmic dust between Earth and Sun.	A pair of probes launched into heliocentric orbit for the purpose of studying solar processes. A joint venture of West Germany's space agency DFVLR and U.S. NASA. Max Planck Institute, Honeysuckle Creek
7	Helios B	Titan IIIE	Germany, U.S.	1976	1985
8	ISEE-3	Delta-2914	U.S.	1978	1982	Observed solar phenomena in conjunction with earth-orbiting ISEE-1 and ISEE-2; later renamed International Cometary Explorer (ICE) and directed to Comet Giacobini-Zinner.	The Explorer-class heliocentric spacecraft, ISEE 3 (International Sun-Earth Explorer 3), was part of the mother / daughter / heliocentric mission (ISEE 1, ISEE 2, and ISEE 3). Space College
9	Ulysses	Space Shuttle STS-41	Europe, U.S.	1990	2008	Solar south and north polar observations to investigate the solar wind, interplanetary magnetic field, cosmic rays, neutral interstellar gas and energetic particles.	Formerly the International Solar Polar Mission (ISPM). ESA
10	WIND	Delta II 7925-10	U.S.	1994	-	Solar wind measurements.	Global Geospace Science (GGS) Wind satellite, a NASA science spacecraft. NASA
11	SOHO	Atlas II AS	Europe, U.S.	1996	-	Investigation of Sun's core, corona, and solar wind; comet discoveries.	The Solar and Heliospheric Observatory (SOHO) was built by a European consortium. Originally planned as a two-year mission, it continues to operate after over 20 years. ESA / NASA
12	ACE	Delta 7920-8	U.S.	1997	-	Studies matter comprising energetic particles from the solar wind, the interplanetary medium, and other sources.	Advanced Composition Explorer (ACE), a NASA Explorers program Solar and space exploration spacecraft, remains in operation. Caltech
13	Genesis	Delta 7326-9.5	U.S.	2001	2004	Part of NASA's Discovery program, it flew to the Earth-Sun L1 point and spent two years collecting samples of the solar wind.	It crash landed on return to Earth but useful data was salvaged. Genesis - JPL, Genesis (Discovery 5)
14	STEREO A	Delta 7925-10L	U.S.	2006	2016	Stereoscopic imaging of coronal mass ejections and other solar phenomena.	STEREO (Solar TErrestrial RElations Observatory) is the third mission in NASA's Solar Terrestrial Probes program. This two-year mission will employ two nearly identical space-based observatories. Goddard Space Flight Center, Johns Hopkins APL
15	STEREO B	Delta 7925-10L	U.S.	2006	2016
16	DSCOVR	SpaceX Falcon 9 v1.1	U.S.	2015	-	Solar wind and coronal mass ejection monitoring, as well as Earth climate monitoring.	Deep Space Climate Observatory (DSCOVR; formerly known as Triana) is a NOAA satellite. NOAA
17	Parker Solar Probe	Delta-4H (upg.)	U.S.	2018	-	Close-range solar coronal study.	Parker Solar Probe (previously Solar Probe, Solar Probe Plus, or Solar Probe+) is a NASA robotic spacecraft. Johns Hopkins APL
18	Solar Orbiter	Atlas V 411 (AV-087)	Europe	2020	-	Intended to perform detailed measurements of the inner heliosphere and nascent solar wind, and perform close observations of the polar regions of the Sun.	ESA program with NASA as a joint operator and contributor. ESA - Solar Orbiter
19	Aditya-L1	PSLV C57	India	2023	-	Named from Sanskrit: Aditya, "Sun" and L1, "Lagrange point 1" the spacecraft is studying the solar atmosphere, solar magnetic storms, and their impact on the environment around the Earth.	Designed and developed by the Indian Space Research Organisation (ISRO) and other Indian Research Institutes. ISRO - Aditya-L1

Spacecraft and Launcher Gallery

This gallery contains images of spacecraft and their launch vehicles (rockets) used on the above missions. (Numbers relate to the table above)

Thumbnails: Click on a thumbnail image to enlarge it. | Enlarged image: Click on right side of image for next image or on left side for previous image. Click outside image to close.