A corona is the outermost layer of a star's atmosphere. It is a hot but relatively dim region of plasma populated by intermittent coronal structures known as solar prominences or filaments.
Reuven Ramaty High Energy Solar Spectroscopic Imager was a NASA solar flare observatory. It was the sixth mission in the Small Explorer program (SMEX), selected in October 1997 and launched on 5 February 2002, at 20:58:12 UTC. Its primary mission was to explore the physics of particle acceleration and energy release in solar flares.
Transition Region and Coronal Explorer was a NASA heliophysics and solar observatory designed to investigate the connections between fine-scale magnetic fields and the associated plasma structures on the Sun by providing high-resolution images and observation of the solar photosphere, the transition region, and the solar corona. A main focus of the TRACE instrument is the fine structure of coronal loops low in the solar atmosphere. TRACE is the third spacecraft in the Small Explorer program, launched on 2 April 1998, and obtained its last science image on 21 June 2010, at 23:56 UTC.
The Solar Orbiter (SolO) is a Sun-observing probe developed by the European Space Agency (ESA) with a National Aeronautics and Space Administration (NASA) contribution. Solar Orbiter, designed to obtain detailed measurements of the inner heliosphere and the nascent solar wind, will also perform close observations of the polar regions of the Sun which is difficult to do from Earth. These observations are important in investigating how the Sun creates and controls its heliosphere.
CHIPS was a NASA Explorer program satellite. It was launched on 12 January 2003 from Vandenberg Air Force Base aboard a Delta II with the larger satellite ICESat, and had an intended mission duration of one year. CHIPS was the second of NASA's University Explorer (UNEX) mission class. It performed spectroscopy from 90 to 250 Angstrom extreme ultraviolet (EUV) light.
The Solar Dynamics Observatory (SDO) is a NASA mission which has been observing the Sun since 2010. Launched on 11 February 2010, the observatory is part of the Living With a Star (LWS) program.
Hinode, formerly Solar-B, is a Japan Aerospace Exploration Agency Solar mission with United States and United Kingdom collaboration. It is the follow-up to the Yohkoh (Solar-A) mission and it was launched on the final flight of the M-V rocket from Uchinoura Space Center, Japan on 22 September 2006 at 21:36 UTC. Initial orbit was perigee height 280 km, apogee height 686 km, inclination 98.3 degrees. Then the satellite maneuvered to the quasi-circular Sun-synchronous orbit over the day/night terminator, which allows near-continuous observation of the Sun. On 28 October 2006, the probe's instruments captured their first images.
The Extreme Ultraviolet Explorer was a NASA space telescope for ultraviolet astronomy. EUVE was a part of NASA's Explorer spacecraft series. Launched on 7 June 1992 with instruments for ultraviolet (UV) radiation between wavelengths of 7 and 76 nm, the EUVE was the first satellite mission especially for the short-wave ultraviolet range. The satellite compiled an all-sky survey of 801 astronomical targets before being decommissioned on 31 January 2001.
In solar physics, a coronal loop is a well-defined arch-like structure in the Sun's atmosphere made up of relatively dense plasma confined and isolated from the surrounding medium by magnetic flux tubes. Coronal loops begin and end at two footpoints on the photosphere and project into the transition region and lower corona. They typically form and dissipate over periods of seconds to days and may span anywhere from 1 to 1,000 megametres in length.
Interface Region Imaging Spectrograph (IRIS), also called Explorer 94 and SMEX-12, is a NASA solar observation satellite. The mission was funded through the Small Explorer program to investigate the physical conditions of the solar limb, particularly the interface region made up of the chromosphere and transition region. The spacecraft consists of a satellite bus and spectrometer built by the Lockheed Martin Solar and Astrophysics Laboratory (LMSAL), and a telescope provided by the Smithsonian Astrophysical Observatory (SAO). IRIS is operated by LMSAL and NASA's Ames Research Center.
A nanoflare is a very small episodic heating event which happens in the corona, the external atmosphere of the Sun.
The High Resolution Coronal Imager (Hi-C) is a sub-orbital telescope designed to take high-resolution images of the Sun's corona. As of 2020 it has been launched three times, but only the first and the third launches, on July 11, 2012, and May 29, 2018, resulted in a successful mission. It was launched aboard a Black Brant IX sounding rocket from White Sands Missile Range, New Mexico. The images taken were the highest resolution photos ever of the Sun's corona.
The Heliophysics Science Division of the Goddard Space Flight Center (NASA) conducts research on the Sun, its extended Solar System environment, and interactions of Earth, other planets, small bodies, and interstellar gas with the heliosphere. Division research also encompasses geospace—Earth's uppermost atmosphere, the ionosphere, and the magnetosphere—and the changing environmental conditions throughout the coupled heliosphere.
Solar phenomena are natural phenomena which occur within the atmosphere of the Sun. They take many forms, including solar wind, radio wave flux, solar flares, coronal mass ejections, coronal heating and sunspots.
Barbara June Thompson is an American solar physicist. She is a scientist at Goddard Space Flight Center where she researches coronal mass ejections and the dynamics of coronal structures. Thompson was the project scientist for NASA's Solar Dynamics Observatory mission through development and early flight.
Polarimeter to Unify the Corona and Heliosphere (PUNCH) is a future mission by NASA to study the unexplored region from the middle of the solar corona out to 1 AU from the Sun. PUNCH will consist of a constellation of four microsatellites that through continuous 3D deep-field imaging, will observe the corona and heliosphere as elements of a single, connected system. The four microsatellites were initially scheduled to be launched in October 2023, but they have since been moved to a launch in rideshare with SPHEREx, scheduled for 27 February 2025.
A solar gravitational lens or solar gravity lens (SGL) is a theoretical method of using the Sun as a large lens with a physical effect called gravitational lensing. It is considered one of the best methods to directly image habitable exoplanets.
Daniel B. Seaton is an American solar physicist based at the Southwest Research Institute (SwRI) in Boulder, Colorado. He is particularly known for his work on producing and interpreting images of the solar corona, using both visible light and extreme ultraviolet.
Bart De Pontieu is a solar physicist who works at Lockheed Martin's Solar & Astrophysics Laboratory. He is known for his work on the dynamics and heating of the solar chromosphere, transition region and corona, via both wave mechanisms and nanoflares. De Pontieu has had a major role in multiple solar scientific space missions, including TRACE, Hinode, the Solar Dynamics Observatory, and IRIS. He is the Principal Investigator of the in-development Multi-slit Solar Explorer selected by NASA in February 2022.
Solar moss is a distinctive feature in the Sun's atmosphere discovered by NASA's Transition Region and Coronal Explorer (TRACE) spacecraft in 1999. It appears as bright, "sponge-like" patches in extreme ultraviolet light, occurring 1,000-3,000 miles above the Sun's visible surface at the base of hot coronal loops in active regions.
