The Fermi Gamma-ray Space Telescope is opening a wide new window on the universe. Gamma rays are the highest-energy form of light, and the gamma-ray sky is radically different from the one we perceive with our own eyes. Fermi is advancing our understanding of a broad range of topics, including supermassive black holes, dark matter studies, the physics of pulsars and gamma-rays bursts, and the origin of cosmic rays. The mission observes high-energy gamma rays over a broad range of energies as well as more focused gamma-ray bursts. Fermi was launched in 2008.
The Swift mission observes gamma-ray bursts and probes conditions in the distant (high-redshift) universe. The mission consists of three instruments on a spacecraft that can rapidly reorient itself to observe new targets. Within seconds of detecting a burst, Swift relays a burst's location to ground stations. This enables both ground-based and space-based telescopes around the world to target and observe the burst's afterglow. The spacecraft observes approximately 100 gamma-ray bursts per year. Swift was launched in 2004.
INTEGRAL is a European Space Agency (ESA) mission with participation by NASA and Russia to provide imaging and spectroscopy of the gamma-ray sky. The satellite observes the most violent and exotic objects of the universe and helps us to understand the formation of new chemical elements, the extreme conditions near the outer edges (event horizons) of black holes, and other essential astrophysical issues. ESA launched the observatory in 2002.
The Advanced Composition Explorer (ACE) studies energetic particles from the sun as well as sources within and outside our galaxy. ACE observations contribute to our understanding of the formation and evolution of the solar system as well as the astrophysical processes involved. NASA's Goddard Space Flight Center provided detectors and telescopes for several of ACE's instruments. The mission launched in 1997.
NASA scientists have flown several instruments on high-altitude balloons to study the origin of cosmic rays. The Balloon Experiment Superconducting Spectrometer (BESS), in partnership with the University of Tokyo, observes antimatter cosmic rays. The Cosmic Ray Energetic and Mass (CREAM) with University of Maryland, targets high-energy cosmic rays. And the Super Trans-Iron Galactic Element Recorder (SuperTIGER) with Washington University, focuses on cosmic ray elemental abundances.
The Galaxy Evolution Explorer (GALEX) is an orbiting space telescope that is investigating the causes and evolution of star formation in galaxies over the history of the universe. The telescope will help scientists understand how do galaxies grow and change over 10 billion years of cosmic history. It surveys millions of galaxies at ultraviolet wavelengths, enabling researchers to determine where and how rapidly stars are forming within the galaxies. An aircraft-launched Pegasus rocket took GALEX into orbit in April 2003.
The High Energy Astrophysics Science Archive Research Center (HEASARC) is the primary archive for NASA missions dealing with extremely energetic phenomena, from black holes to the Big Bang. Having recently merged with the Legacy Archive for Microwave Background Data Analysis (LAMBDA), it includes data obtained by NASA's high-energy astronomy missions from the extreme ultraviolet through gamma-ray bands, along with missions that study the relic cosmic microwave background.
The Hubble Space Telescope (HST) is a multi-instrument observatory that has dramatically changed humanity's understanding of the universe for over two decades, with dramatic images of stars, planets, and galaxies. Hubble orbits Earth; its position above the atmosphere, which distorts and reduces the light that reaches the surface, gives it a view of the universe that typically surpasses that of ground-based telescopes. HST's various instruments investigate the universe in the visible, ultraviolet, and infrared portions of the spectrum. HST was deployed from the space shuttle Discovery on April 25, 1990. After that, the telescope underwent five servicing missions to repair or upgrade various instruments and systems.
The Solar TErrestrial RElations Observatory (STEREO) mission consists of two nearly identical solar observatories. One orbits ahead of Earth; the other trails behind. When positioned 180-degrees apart in their orbits, the spacecraft can observe the entire sun simultaneously. STEREO traces the flow of energy and matter from the sun to Earth. It also probes the 3D structure of coronal mass ejections - violent eruptions of matter from the sun that can disrupt satellites and power grids - and help us understand why they happen. NASA's Goddard Space Flight Center provided particle detectors and a telescope for STEREO's IMPACT suite of instruments. The mission launched in 2006.
The Space Telescope Imaging Spectrograph (STIS) is an instrument on the Hubble Space Telescope. It combines a camera with a spectrograph, and covers a wide range of wavelengths from the near-infrared region into the ultraviolet. The spectrograph spreads out light gathered by the Hubble Space Telescope so that it can be analyzed to determine things like the chemical composition, motions, and temperatures of astronomical objects. STIS also has an instrument called a coronagraph. It can block light from bright objects in a region being observed, which make sit possible to study fainter targets nearby. STIS was installed on the Hubble Space Telescope during Servicing Mission 2 in 1997. The instrument malfunctioned in August 2004, and was repaired during Servicing Mission 4 in 2009.
Suzaku, formerly Astro-E2, is Japan's fifth X-ray astronomy mission. It was developed by Japan in collaboration with NASA and MIT. The mission's objective is to observe a variety of X-ray sources at high-energy resolution and sensitivity. Suzaku is the recovery mission for ASTRO-E, which failed to achieve orbit during launch in February 2000. Suzaku launched in July 2005. Goddard Space Flight Center helped develop one of Suzaku's instruments and manages the mission's Guest Observer Program.
Wide Field Camera 3 (WFC3) is an instrument on the Hubble Space Telescope. Astronauts installed WFC3 during the final servicing mission to the space observatory in May 2009. With a "panchromatic" grasp of light extending from the ultraviolet through the visible and into the infrared, WFC3 is an extremely powerful imaging instrument, extending Hubble's capabilities by seeing deeper into the universe.
The Wilkinson Microwave Anisotropy Probe (WMAP) created a map of temperature fluctuations in the cosmic background radiation -- the remnant afterglow of the hot young universe -- at much higher resolution, sensitivity, and accuracy than its predecessor, the Cosmic Background Explorer (COBE). WMAP observations shed light on several key questions in cosmology, including the structure and physical parameters of the universe. WMAP was launched into orbit in 2001. Observations formally concluded in October 2010, although analysis of the data continues.
The Wind mission's goals are to study the magnetosphere and ionosphere and investigate basic plasma processes occurring in the near-Earth solar wind. The Wind spacecraft orbits upstream from Earth in the solar wind, which is the flow of electrically charged particles streaming from the surface of the sun. Wind observes the solar wind before it impacts Earth's magnetic field. The spacecraft was launched in 1994.
The X-ray Multi-Mirror (XMM-Newton) mission is a joint project of the European Space Agency (ESA) and NASA. XMM-Newton is designed to observe high-energy X-rays emitted by exotic astronomical objects such as pulsars, black holes, and active galaxies. The observatory collects both images and spectra. This means it can measure the energy of the X-rays emitted by an astronomical object, which allows scientists to determine many of its physical characteristics. Besides having funded elements of the XMM-Newton instrument package, NASA also provides the NASA Guest Observer Facility (GOF) for XMM Newton at Goddard Space Flight Center. ESA launched the mission in December 1999.
