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Fermi Gamma-ray Space Telescope

2011 News

Dec 21, 2011

Cycle-5 Proposal Deadline is One Month Away

Reminder: Fermi Cycle-5 Guest Investigator Proposals are due on January 20, 2012. Please refer to the proposals page for details on how to prepare and submit a proposal. We look forward to your participation in Fermi mission cycle 5.

Dec 19, 2011

The First GBM Gamma-Ray Burst (GRB) Catalog is Now Available Online

The catalog contents are internally documented, and more detailed explanations will be appearing in upcoming journal papers. The searchable catalog contains general, temporal, and spectral characteristics of nearly 500 GRBs seen by GBM during the first two years of Fermi operations.
+ Learn More

Dec 13, 2011

NASA's Fermi Shows That Tycho's Star Shines in Gamma Rays

In early November 1572, observers on Earth witnessed the appearance of a "new star" in the constellation Cassiopeia, an event now recognized as the brightest naked-eye supernova in more than 400 years. It's often called "Tycho's supernova" after the great Danish astronomer Tycho Brahe, who gained renown for his extensive study of the object. Now, years of data collected by NASA's Fermi Gamma-Ray Space Telescope reveal that the shattered star's remains shine in high-energy gamma rays.
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Nov 28, 2011

In The Heart Of Cygnus, NASA's Fermi Reveals A Cosmic-ray Cocoon

The constellation Cygnus, now visible in the western sky as twilight deepens after sunset, hosts one of our galaxy's richest-known stellar construction zones. Astronomers viewing the region at visible wavelengths see only hints of this spectacular activity thanks to a veil of nearby dust clouds forming the Great Rift, a dark lane that splits the Milky Way, a faint band of light marking our galaxy's central plane.
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Nov 3, 2011

NASA's Fermi Finds Youngest Millisecond Pulsar, 100 Pulsars To-Date

An international team of scientists using NASA's Fermi Gamma-ray Space Telescope has discovered a surprisingly powerful millisecond pulsar that challenges existing theories about how these objects form.
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Nov 1, 2011

Call for Proposals for Cycle-5

The call for proposals to participate in the Fermi Cycle-5 Guest Investigator program has been issued by NASA Headquarters as an amendment to the 2011 ROSES NRA. Please refer to the proposals page for details and to obtain a copy of the Fermi Cycle-5 NRA text.

Oct 28, 2011

Fermi Sun-Pointing Event

The Fermi observatory entered a sun-pointing attitude on Friday, October 21st at 06:02 UT and resumed normal data-taking at 10:43 UT the same day. The mode change was in response to an inconsistency in attitude solutions on board the spacecraft after the end of a scheduled nadir observation. The operations team has established that this was unlikely to be due to a hardware problem on the observatory and are investigating improvements to operations to prevent this in the future.

Oct 26, 2011

GBM LLT Settings

In order to support Fermi pointed observations without loss of data quality or excessive data volume, the GBM team is occasionally adjusting the level of the discriminators for the sun-facing NaI detectors (NaI 0 - 5) so that their energy threshold is higher than in nominal mode. During these periods of non-standard Low Level Threshold (LLT) operation, photons with energies below this threshold are not recorded. Data above this threshold energy are nominal, as are all data from the BGO detectors and from NaI detectors 6-11. The energy thresholds of the affected detectors is between 18 - 30 keV, depending on the nature of the pointing. A list of time spans with non-standard LLT settings is available, along with instructions for data selection during these periods. This list will be promptly updated as changes occur. Outside these periods, thresholds are nominal. Questions regarding this and other issues regarding GBM data should be addressed to fermihelp@milkyway.gsfc.nasa.gov.
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Sep 9, 2011

Fermi's Latest Gamma-ray Census Highlights Cosmic Mysteries

Every three hours, NASA's Fermi Gamma-ray Space Telescope scans the entire sky and deepens its portrait of the high-energy universe. Every year, the satellite's scientists reanalyze all of the data it has collected, exploiting updated analysis methods to tease out new sources. These relatively steady sources are in addition to the numerous transient events Fermi detects, such as gamma-ray bursts in the distant universe and flares from the sun.
+ Learn More

Aug 5, 2011

Pass 7 Data Release & Fermi Science Tools Update

The LAT team have provided a new classification of LAT data that provides increased effective area at low energies, more accurate effective area in the several-GeV energy range, and improved or comparable levels of residual cosmic rays. The photon classes have been fully redefined for this analysis, resulting in a new Pass 7 data set. The LAT team have also provided an improved description of instrument performance, characterized as a new set of instrument response functions (IRFs). The updated IRFs are available with the new version of the Fermi Science Tools(v9r23p1).
+ Download New Science Tools
+ Retrieve Pass 7 LAT Data

Jul 12, 2011

Second LAT Catalog Released

We are pleased to announce the release of the second catalog of Fermi-LAT sources. The 2FGL catalog is based on the first two years of LAT science data. The catalog is provided as a FITS table and as PDF files, and is accompanied by important caveats as well as a draft of the paper describing the details of the catalog preparation. The 2FGL catalog represents a major milestone and is a great accomplishment by the international Fermi-LAT team.
+ Read About It

Jun 29, 2011

'Odd Couple' Binary Makes Dual Gamma-ray Flares

In December 2010, a pair of mismatched stars in the southern constellation Crux whisked past each other at a distance closer than Venus orbits the sun. The system possesses a so-far unique blend of a hot and massive star with a compact fast-spinning pulsar. The pair's closest encounters occur every 3.4 years and each is marked by a sharp increase in gamma rays, the most extreme form of light.
+ Learn More

May 25, 2011

New Fermi Science Tools Release (v9r23p1)

A new version of the Fermi Science Tools is now available. This version includes bug fixes as well as support for improved instrument response functions including in-flight corrections to the PSF and has a correction to the effective area. The release notes are available here.
+ Download & Installation

May 20, 2011

Radio Telescopes Capture Best-Ever Snapshot of Black Hole Jets

An international team, including NASA-funded researchers, using radio telescopes located throughout the Southern Hemisphere has produced the most detailed image of particle jets erupting from a supermassive black hole in a nearby galaxy.
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May 16, 2011

GBM Data Processing Pipeline Restored

The GBM data processing pipeline is restored and the backlog of data has been cleared. The processed data are available via the HEASARC browse interface and from the Fermi FTP site.

May 11, 2011

NASA's Fermi Spots 'Superflares' in the Crab Nebula

The famous Crab Nebula supernova remnant has erupted in an enormous flare five times more powerful than any flare previously seen from the object. On April 12, NASA's Fermi Gamma-ray Space Telescope first detected the outburst, which lasted six days.
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May 3, 2011

Storms Affect GBM Data Processing and Delivery

Due to the storms in the southeast, data from the GBM instrument is currently not being processed or posted to the FSSC. Communication of real time burst locations via GCN notices continues unhindered. Data processing and delivery of new and backlogged files will resume once power is restored, which is estimated to occur anywhere from mid next week to 15-30 days hence.

Apr 29, 2011

Fermi Cycle 4: List of Approved Guest Investigations

The phase-1 selection process for the Fermi Gamma-Ray Space Telescope Cycle-4 Guest Investigator Program has been completed. A total of 213 proposals were received in response to the cycle-4 NRA and 85 have been selected by NASA Headquarters on the basis of scientific peer-review evaluation completed in early April. A list of the titles and abstracts of the selected programs is available here

Mar 30, 2011

TOO for Cyg X-3

A 500 ks TOO pointed mode observation for Cyg X-3 was requested and initiated on Friday, March 25th in response to an increase in gamma-ray activity from the source (ATel 3233). The TOO was terminated manually Monday, March 28th. Stay informed by subscribing to the Fermi-News mailing list.
+ Sign up for Fermi-News

Feb 16, 2011

Fermi Makes APS's "Top Ten Physics-Related News Stories of 2010"

In early November astronomers at the Harvard-Smithsonian Center for Astrophysics, using observations taken from the Fermi Gamma-ray Space Telescope, announced the surprising discovery of two gigantic bubbles or lobes of gamma-ray-emitting gas surrounding the Milky Way Galaxy.
+ Learn More

Feb 4, 2011

Fermi LAT Data Server Online

The Fermi LAT data server is now back online and is up-to-date. You may also access the LAT weekly files through the Browse Interface or directly using FTP. We are evaluating other dynamic content and may make those available once the security reviews are complete.

Feb 2, 2011

2011 Fermi Symposium

The 2011 Fermi Symposium will be held in Rome, Italy from May 9-12, 2011.
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Jan 27, 2011

Fermi Cycle 4 Proposals

The Fermi Cycle-4 proposal submission deadline was on January 21, 2011. A total of 213 guest investigator proposals were received in response the to Cycle-4 NRA. Selections will be announced by NASA HQ in the spring following scientific peer-review evaluation in early April 2011.

Jan 12, 2011

NASA Satellites Find High-Energy Surprises in 'Constant' Crab Nebula

The combined data from several NASA satellites has astonished astronomers by revealing unexpected changes in X-ray emission from the Crab Nebula, once thought to be the steadiest high-energy source in the sky.
» Learn more

Jan 10, 2011

NASA's Fermi Catches Thunderstorms Hurling Antimatter into Space

Scientists using NASA's Fermi Gamma-ray Space Telescope have detected beams of antimatter produced above thunderstorms on Earth, a phenomenon never seen before.
» Learn more