Cosmic Background Explorer (COBE)

The purpose of the Cosmic Background Explorer (COBE) mission was to take precise measurements of the diffuse radiation between 1 micrometer and 1 cm over the whole celestial sphere. The following quantities were measured: (1) the spectrum of the 3 K radiation over the range 100 micrometers to 1 cm; (2) the anisotropy of this radiation from 3 to 10 mm; and, (3) the spectrum and angular distribution of diffuse infrared background radiation at wavelengths from 1 to 300 micrometers.

The experiment module contained the instruments and a dewar filled with 650 liters of 1.6 K liquid helium, with a conical sun shade. The base module contained the attitude control, communications and power systems. The satellite rotated at 1 rpm about the axis of symmetry to control systematic errors in the anisotropy measurements and to allow observations of the zodiacal light at various solar elongation angles. The orientation of the spin axis was maintained anti-earth and at 94 degrees to the sun-earth line. The operational orbit was dawn-dusk sun-synchronous so that the sun was always to the side and thus was shielded from the instruments. With this orbit and spin-axis orientation, the instruments performed a complete scan of the celestial sphere every six months.

Instrument operations were terminated 1993-12-23. As of January 1994, engineering operations were to conclude that month, after which operation of the spacecraft would be transferred to Wallops for use as a test satellite.

The CGRO Mission(1991 - 2000)

The Compton Gamma Ray Observatory was the second of NASA's Great Observatories. Compton, at 17 tons, was the heaviest astrophysical payload ever flown at the time of its launch on April 5, 1991 aboard the space shuttle Atlantis. Compton was safely deorbited and re-entered the Earth's atmosphere on June 4, 2000.

Compton had four instruments that covered an unprecedented six decades of the electromagnetic spectrum, from 30 keV to 30 GeV. In order of increasing spectral energy coverage, these instruments were the Burst And Transient Source Experiment (BATSE), the Oriented Scintillation Spectrometer Experiment (OSSE), the Imaging Compton Telescope (COMPTEL), and the Energetic Gamma Ray Experiment Telescope (EGRET). For each of the instruments, an improvement in sensitivity of better than a factor of ten was realized over previous missions.

The Observatory was named in honor of Dr. Arthur Holly Compton, who won the Nobel prize in physics for work on scattering of high-energy photons by electrons - a process which is central to the gamma-ray detection techniques of all four instruments.

CGRO Observation Timelines

CloudSat Profiles Tornadic Outbreak

The intense thunderstorms responsible for this week's deadly outbreak of tornadoes in Tennessee, Kentucky, Mississippi, Alabama and Arkansas were imaged by the Cloud Profiling Radar on NASA's CloudSat satellite on February 5.
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Clementine Project Information

Clementine was a joint project between the Strategic Defense Initiative Organization and NASA. The objective of the mission was to test sensors and spacecraft components under extended exposure to the space environment and to make scientific observations of the Moon and the near-Earth asteroid 1620 Geographos. The observations included imaging at various wavelengths including ultraviolet and infrared, laser ranging altimetry, and charged particle measurements. These observations were originally for the purposes of assessing the surface mineralogy of the Moon and Geographos, obtaining lunar altimetry from 60N to 60S latitude, and determining the size, shape, rotational characteristics, surface properties, and cratering statistics of Geographos.

Clementine was launched on 25 January 1994 at 16:34 UTC (12:34 PM EDT) from Vandenberg AFB aboard a Titan IIG rocket. After two Earth flybys, lunar insertion was achieved on February 21. Lunar mapping took place over approximately two months, in two parts. The first part consisted of a 5 hour elliptical polar orbit with a perilune of about 400 km at 28 degrees S latitude. After one month of mapping the orbit was rotated to a perilune of 29 degrees N latitude, where it remained for one more month. This allowed global imaging as well as altimetry coverage from 60 degrees S to 60 degrees N.

After leaving lunar orbit, a malfunction in one of the on-board computers on May 7 at 14:39 UTC (9:39 AM EST) caused a thruster to fire until it had used up all of its fuel, leaving the spacecraft spinning at about 80 RPM with no spin control. This made the planned continuation of the mission, a flyby of the near-Earth asteroid Geographos, impossible. The spacecraft remained in geocentric orbit and continued testing the spacecraft components until the end of mission.

More information on the Clementine mission, instruments, and early results can also be found in the Clementine special issue of Science magazine, Vol. 266, No. 5192, December 1994.

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Clementine Flight Plan (1994)

January 25   Launch (16:34 UTC)
February 3   Leave Earth Orbit
February 5   First Earth Flyby
February 15  Second Earth Flyby
February 19  Enter Lunar Orbit
February 26  Start of Systematic Mapping - Cycle 1 (South)
March 26     End of Cycle 1, Start of Cycle 2 (North)
April 21     Completion of Cycle 2
May 5        Exit Lunar Orbit
(May 7        Computer Malfunction (14:39 UTC))
*May          Earth and Lunar Flybys
*June-August  Cruise to Geographos
*August 31    Geographos Flyby

Chandra - A New Way to Weigh Giant Black Holes

How do you weigh the biggest black holes in the universe? One answer can be found from a new technique that astronomers have developed using data from NASA's Chandra X-ray Observatory. By measuring a peak temperature in the hot gas in the center of the giant elliptical galaxy NGC 4649, scientists have determined the mass of the galaxy's supermassive black hole -- providing consistent results with a traditional technique.

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The CHAMP Mission

CHAMP (CHAllenging Minisatellite Payload) is a German small satellite mission for geoscientific and atmospheric research and applications, managed by GFZ. With its highly precise, multifunctional and complementary payload elements (magnetometer, accelerometer, star sensor, GPS receiver, laser retro reflector, ion drift meter) and its orbit characteristics (near polar, low altitude, long duration) CHAMP will generate for the first time simultaneously highly precise gravity and magnetic field measurements over a 5 years period. This will allow to detect besides the spatial variations of both fields also their variability with time. The CHAMP mission will open a new era in geopotential research and will become a significant contributor to the Decade of Geopotentials.

In addition with the radio occultation measurements onboard the spacecraft and the infrastructure developed on ground, CHAMP will become a pilot mission for the pre-operational use of space-borne GPS observations for atmospheric and ionospheric research and applications in weather prediction and space weather monitoring.

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Cassini to Earth: 'Mission Accomplished, But New Questions Await!'

NASA's Cassini mission is closing one chapter of its journey at Saturn and embarking on a new one with a two-year mission that will address new questions and bring it closer to two of its most intriguing targets—Titan and Enceladus.
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Public release of CALIPSO Data Products

12.08.06: Public release of CALIPSO Data Products

The Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observation (CALIPSO) satellite mission is pleased to announce an initial release of its data products. CALIPSO provides new insight into the role that clouds and atmospheric aerosols (airborne particles) play in regulating Earth's weather, climate, and air quality. CALIPSO is a joint mission between NASA and CNES, the French space agency.

CALIPSO's payload includes an active lidar (CALIOP), a passive Infrared Imaging Radiometer (IIR), and visible Wide Field Camera. This data release consists of data beginning in mid June 2006 and includes Level 1 radiances from each of the instruments. This release also includes the lidar Level 2 vertical feature mask and cloud and aerosol layer products. The CALIPSO data are available through the Atmospheric Sciences Data Center (ASDC) at NASA Langley Research Center and can be accessed at the following URL:

» + http://eosweb.larc.nasa.gov/PRODOCS/calipso/table_calipso.html

Reference resources on the CALIPSO data set, including detailed data quality summaries and a data catalog are also available at the ASDC CALIPSO page.

If you have questions concerning the ordering of CALIPSO data products, contact User Services at larc@eos.nasa.gov.

Aura Mission, Understanding and Protecting the Air We Breathe

The Llaima Volcano is one of Chile's most active volcanoes and has frequent but moderate eruptions. An eruption on January 1, 2008 forced the evacuation of hundreds of people from nearby villages.

The volcano at least erupted 60 times from Tuesday to Wednesday, while there were no immediate reports of casualties or damage, officials said. The Llaima volcano in southern Chile erupted, sending a huge plume of smoke into the air, located some 850 km (528 miles) south of Santiago. The volcanic ash expelled by Llaima travelled east over the Andes into Argentina.

Aura's OMI instrument captured a near-real time image of the sulfer dioxide (SO2) plume from the Llaima volcanic eruption. The SO2 cloud (red color) off the coast of Argentina was from Aura overpass on January 2 and over South Atlantic on January 3.

This is the first eruption from Llaima since 1994. Chile, after Indonesia, has the world's second biggest and second most active chain of volcanoes.

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Astro 2 - Mission

Following the scientific success of the Astro-1 mission, Astro-2 was approved as a follow-up flight. The three ultraviolet telescopes, which flew on Astro-1, were reassembled for Astro-2. These telescopes were (1) the Ultraviolet Imaging Telescope (UIT) operating in the 1200-3100 Angstrom range, (2) the Hopkins Ultraviolet Telescope (HUT) operating from 425 to 1850 Angstroms, and (3) the Wisconsin Ultraviolet Photopolarimetry Experiment (WUPPE) operating from 1250 to 3200 Angtroms. HUT was significantly upgraded for this second flight, with new optical coatings, which enhanced the telescope's performance by more than a factor of two. The three telescopes were planned to make simultaneous observations of objects such as stars, galaxies and quasars, since many science objectives and selected astronomical targets of the three instrument teams are interrelated. BBXRT, which was onboard ASTRO 1, was not flown on ASTRO 2.

The telescopes were mounted on a Spacelab pallet in the payload bay of the shuttle (flight STS-67). The Spacelab Instrument Pointing System (IPS), pallets, and avionics were utilized for attachment to the Shuttle and for control and data handling. The IPS provides a stable platform, keeps the telescopes aligned, and provides various pointing and tracking capabilities to the telescopes. The Astro observatory requires both mission specialists and payload specialists to control its operations from the Shuttle aft flight deck. Instrument monitoring and quick-look data analysis are planned for real-time ground operations.

The Guest Observer Program was included for Astro-2. The telescopes observed over 250 astronomical objects before returning to earth after a 16-day flight.

Astro 1 - Mission

The "Astro Observatory" was developed as a system of telescopes that could fly multiple times on the space shuttle. Astro-1 consisted of three ultraviolet telescopes and an X-ray telescope. The primary objectives of this observatory were to obtain (1) imagery in the spectral range 1200-3100 A (Ultraviolet Imaging Telescope, UIT); (2) spectrophotometry in the spectral region 425 to 1850 A (Hopkins Ultraviolet Telescope, HUT); (3)spectrapolarimetry from 1250 to 3200 A (Wisconsin Ultraviolet Photopolarimetry Experiment, WUPPE); and (4) X-ray data in the bandpass between 0.3 and 12 keV (Broad Band X-ray Telescope, BBXRT). Since many science objectives and selected astronomical targets of the three instrument teams were inter-related, simultaneous observations by all four instruments were planned.

The telescopes were mounted on a Spacelab pallet in the payload bay of the shuttle (flight STS-35). The Spacelab Instrument Pointing System (IPS), pallets, and avionics were utilized for attachment to the Shuttle and for control and data handling. Astro-1 required both mission specialists and payload specialists to control its operations from the Shuttle aft flight deck. Instrument monitoring and quick-look data analysis were performed for real-time ground operations. During the flight both on-board Digital Display Units malfunctioned, and the star guidance system calibration was not possible. The observing sequences were rescheduled during the flight, and instrument pointing was done by hand by the astronauts, and from the ground.

As a result of the numerous technical glitches, the returned data volume was less than half of that originally planned, and the scientific return was about 67% of the stated goals of the mission. Astro-1 was returned to earth 17:54 U.T., December 11, 1990. However, the mission was very successful in that 231 observations of 130 unique astronomical targetrs were made.

The follow-up flight, Astro-2, was dedicated to studies of many astronomical objects, and included increasing participation of guest investigators.

NASA Successfully Tests Parachute for Ares Rocket

NASA and industry engineers have successfully completed the first drop test of a drogue parachute for the Ares I rocket. The drogue parachute is designed to slow the rapid descent of the spent first-stage motor, cast off by the Ares I rocket during its climb to space. The successful test is a key early milestone in development and production of the Ares I rocket, the first launch vehicle for NASA's Constellation Program that will send explorers to the International Space Station, the moon and beyond in coming decades.

Overview: Ares Launch Vehicles

NASA's Ares rockets, named for the Greek god associated with Mars, will return humans to the moon and later take them to Mars and other destinations.

Future astronauts will ride to orbit on Ares I, which uses a single five-segment solid rocket booster, a derivative of the space shuttle's solid rocket booster, for the first stage. A liquid oxygen/liquid hydrogen J-2X engine derived from the J-2 engine used on Apollo's second stage will power the crew exploration vehicle's second stage. The Ares I can lift more than 55,000 pounds to low Earth orbit.

Planning and early design are under way for hardware, propulsion systems and associated technologies for NASA's Ares V cargo launch vehicle -- the "heavy lifter" of America’s next-generation space fleet. Ares V will serve as NASA's primary vessel for safe, reliable delivery of large-scale hardware to space -- from the lunar landing craft and materials for establishing a moon base, to food, fresh water and other staples needed to extend a human presence beyond Earth orbit.

ARCTAS - Forest Fire Smoke Plumes Probed

In a nondescript room on a Canadian Air Force Base, an international team of fire trackers, weather forecasters and various atmospheric scientists puzzle over computer models, satellite tracks and flight charts. Their goal is to find the best fire targets and tailor the flight path of NASA’s airborne laboratories to track and investigate the properties of smoke plumes.

The researchers are part of the summer deployment of NASA’s Arctic Research of the Composition of the Troposphere from Aircraft and Satellites, or ARCTAS, mission. The mission is just five days into its summer study of the smoke plumes from northern latitude forest fires, and already the choreographed effort between modelers and experimenters is producing a wealth of new data.

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WHAT IS AQUARIUS ?

Aquarius is a focused satellite mission to measure global Sea Surface Salinity (SSS). Scientific progress is limited because conventional in situ SSS sampling is too sparse to give the global view of salinity variability that only a satellite can provide. Aquarius is planning to launch in 2010. Aquarius/SAC-D is a space mission developed by NASA and the Space Agency of Argentina (Comisión Nacional de Actividades Espaciales, CONAE.)

MISSION STATUS & EVENTS

• Aquarius passed Mission Confirmation Review on September 28, 2005. Thus the project has completed formulation activities (Phase B), during which the mission requirements, design and costs have been developed and reviewed, and has begun the implementation (Phases C & D), when the flight hardware is built, tested and readied for launch.
• After a four-year development effort, the NASA Goddard Space Flight Center (GSFC) delivered the Aquarius Radiometer to the Jet Propulsion Laboratory (JPL) in Pasadena, California in January 2008. The Radiometer, built by an in-house team of scientists, engineers, and technicians at GSFC is part of the international Aquarius/SAC-D mission. The Radiometer will be integrated with the Aquarius instrument at JPL. (Click here to learn more)

Aqua Mission

Aqua is a major international Earth Science satellite mission centered at NASA. Launched on May 4, 2002, the satellite has six different Earth-observing instruments on board and is named for the large amount of information being obtained about water in the Earth system from its stream of approximately 89 Gigabytes of data a day. The water variables being measured include almost all elements of the water cycle and involve water in its liquid, solid, and vapor forms. Additional variables being measured include radiative energy fluxes, aerosols, vegetation cover on the land, phytoplankton and dissolved organic matter in the oceans, and air, land, and water temperatures.

Apollo: Expandng Our Knowledge of the Solar System

On May 25, 1961, President John F. Kennedy announced the goal of sending astronauts to the moon before the end of the decade. Coming just three weeks after Mercury astronaut Alan Shepard became the first American in space, Kennedy's bold challenge set the nation on a journey unlike any before in human history.

Eight years of hard work by thousands of Americans came to fruition on July 20, 1969, when Apollo 11 commander Neil Armstrong stepped out of the lunar module and took "one small step" in the Sea of Tranquility, calling it "a giant leap for mankind."

Innovation and even improvisation were necessary along the way. In December 1968, rather than letting lunar module delays slow the program, NASA changed plans to keep the momentum going. Apollo 8 would go all the way to the moon and orbit without a lunar module; it was the first manned flight of the massive Saturn V rocket.

Six of the missions -- Apollos 11, 12, 14, 15, 16 and 17 -- went on to land on the moon, studying soil mechanics, meteoroids, seismic, heat flow, lunar ranging, magnetic fields and solar wind. Apollos 7 and 9 tested spacecraft in Earth orbit; Apollo 10 orbited the moon as the dress rehearsal for the first landing. An oxygen tank explosion forced Apollo 13 to scrub its landing, but the "can-do" problem solving of the crew and mission control turned the mission into a "successful failure."

The program also drew inspiration from Apollo 1 astronauts Gus Grissom, Ed White and Roger Chaffee, who lost their lives in a fire during a launch pad test in 1967.

AIM-Mission, NASA Satellite Captures First View of 'Night-Shining Clouds'

The first observations of these "night-shining" clouds by a satellite named "AIM" which means Aeronomy of Ice in the Mesosphere, occurred above 70 degrees north latitude on May 25. People on the ground began seeing the clouds on June 6 over Northern Europe. AIM is the first satellite mission dedicated to the study of these unusual clouds.

These mystifying clouds are called Polar Mesospheric Clouds, or PMCs, when they are viewed from space and referred to as "night-shining" clouds or Noctilucent Clouds, when viewed by observers on Earth. The clouds form in an upper layer of the Earth’s atmosphere called the mesosphere during the Northern Hemisphere’s summer season which began in mid-May and extends through the end of August and are being seen by AIM’s instruments more frequently as the season progresses. They are also seen in the high latitudes during the summer months in the Southern Hemisphere.

Very little is known about how these clouds form over the poles, why they are being seen more frequently and at lower latitudes than ever before, or why they have been growing brighter. AIM will observe two complete cloud seasons over both poles, documenting an entire life cycle of the shiny clouds for the first time.

"It is clear that these clouds are changing, a sign that a part of our atmosphere is changing and we do not understand how, why or what it means," stated AIM principal investigator James Russell III of Hampton University, Hampton, Va. "These observations suggest a connection with global change in the lower atmosphere and could represent an early warning that our Earth environment is being changed."

AIM is providing scientists with information about how many of these clouds there are around the world and how different they are including the sizes and shapes of the tiny particles that make them up. Scientists believe that the shining clouds form at high latitudes early in the season and then move to lower latitudes as time progresses. The AIM science team is studying this new data to understand why these clouds form and vary, and if they may be related to global change.

Once the summer season ends in the Northern Hemisphere around mid- to late August, the Southern Hemisphere spring season starts about three months later in the period around mid- to late November. AIM will then be watching for shining clouds in the Southern Hemisphere from November through mid-March when that season ends.

AIM and is managed at Goddard Space Flight Center, Greenbelt, Md and the AIM Project Data Center is located at Hampton University.