Fermi Gamma-ray Space Telescope Archives

November 24, 2024December 7, 2024 by Matt Williams

A Nearby Supernova Could Finally Reveal Dark Matter

SN 1987a as seen by JWST's Near-Infrared Camera. Credit: NASA, ESA, CSA, M. Matsuura, R. Arendt, C. Fransson

Despite 90 years of research, the nature and influence of Dark Matter continue to elude astronomers and cosmologists. First proposed in the 1960s to explain the rotational curves of galaxies, this invisible mass does not interact with normal matter (except through gravity) and accounts for 85% of the total mass in the Universe. It is also a vital component in the most widely accepted cosmological model of the Universe, the Lambda Cold Dark Matter (LCDM) model. However, according to new research, the hunt for DM could be over as soon as a nearby star goes supernova.

Currently, the axion is considered the most likely candidate for DM, a hypothetical low-mass particle proposed in the 1970s to resolve problems in quantum theory. There has also been considerable research into how astronomers could detect axions by observing neutron stars and objects with powerful magnetic fields. In a recent study supported by the U.S. Department of Energy, a team of astrophysicists at the University of California Berkeley argued that axions could be discovered within seconds of detecting gamma rays from a nearby supernova explosion.

July 31, 2024July 31, 2024 by Evan Gough

Astronomers Uncover New Details in the Brightest Gamma Ray Burst Ever Detected

Artist's depiction of a powerful gamma ray burst. Credit: NASA, ESA and M. Kornmesser

In October 2022, the Fermi Gamma-ray Space Telescope and the Neil Gehrels Swift Observatory detected an extraordinarily powerful Gamma Ray Burst (GRB). It still stands as the Brightest Of All Time (BOAT), and astronomers have been curious about it ever since.

New research has uncovered more details in the burst. What do they tell us about these forceful explosions?

April 18, 2024April 18, 2024 by Scott Alan Johnston

The Mystery of Cosmic Rays Deepens

The Fred Lawrence Whipple Observatory’s 48-inch telescope captured this visible-light image of the Pinwheel galaxy (Messier 101) in June 2023. The location of supernova 2023ixf is circled. The observatory, located on Mount Hopkins in Arizona, is operated by the Center for Astrophysics | Harvard & Smithsonian. Hiramatsu et al. 2023/Sebastian Gomez (STScI)

Cosmic rays are high-energy particles accelerated to extreme velocities approaching the speed of light. It takes an extremely powerful event to send these bits of matter blazing through the Universe. Astronomers theorize that cosmic rays are ejected by supernova explosions that mark the death of supergiant stars. But recent data collected by the Fermi Gamma-ray space telescope casts doubt on this production method for cosmic rays, and has astronomers digging for an explanation.

March 13, 2024March 13, 2024 by Allen Versfeld

Colliding Neutron Stars are the Ultimate Particle Accelerators

This artist’s impression shows two tiny but very dense neutron stars at the point at which they merge and explode as a kilonova. Such a very rare event is expected to produce both gravitational waves and a short gamma-ray burst, both of which were observed on 17 August 2017 by LIGO–Virgo and Fermi/INTEGRAL respectively. Subsequent detailed observations with many ESO telescopes confirmed that this object, seen in the galaxy NGC 4993 about 130 million light-years from the Earth, is indeed a kilonova. Such objects are the main source of very heavy chemical elements, such as gold and platinum, in the Universe.

Gamma-ray telescopes observing neutron star collisions might be the key to identifying the composition of dark matter. One leading theory explaining dark matter it that is mostly made from hypothetical particles called axions. If an axion is created within the intensely energetic environment of two neutron stars merging, it should then decay into gamma-ray photons which we could see using space telescopes like Fermi-LAT.

December 22, 2023December 22, 2023 by Matt Williams

Watch 14 Years of Gamma-Ray Observations in This Fascinating NASA Video

Still from the video showing 14 years of data gathered by the Fermi Gamma-ray Space Telescope. Credit: NASA Goddard

The Fermi Gamma-ray Space Telescope, named in honor of noted physicist Enrico Fermi, has been in operation for almost a decade and a half, monitoring the cosmos for gamma rays. As the highest-energy form of light, these rays are produced by extremely energetic phenomena – like supernovae, neutron stars, quasars, and gamma-ray bursts (GRBs). In honor of this observatory’s long history, NASA’s Goddard Spaceflight Center has released a time-lapse movie that shows data acquired by the Fermi Space Telescope between August 2008 and August 2022.

November 30, 2023November 30, 2023 by Matt Williams

Fermi has Found More than 300 Gamma-Ray Pulsars

Visualization of a fast-rotating pulsar. Credit: NASA's Goddard Space Flight Center Conceptual Image Lab

In June 2008, the Gamma-ray Large Area Space Telescope began surveying the cosmos to study some of the most energetic phenomena in the Universe. Shortly after that, NASA renamed the observatory in the Fermi Gamma-ray Space Telescope in honor of Professor Enrico Fermi (1901-1954), a pioneer in high-energy physics. During its mission, Fermi has addressed questions regarding some of the most mysterious and energetic phenomena in the Universe – like gamma-ray bursts (GRBs), cosmic rays, and extremely dense stellar remnants like pulsars.

Since it began operations, Fermi has discovered more than 300 gamma-ray pulsars, which have provided new insights into the life cycle of stars, our galaxy, and the nature of the Universe. This week, a new catalog compiled by an international team contains the more than 300 pulsars discovered by the Fermi mission – which includes 294 confirmed gamma-ray-emitting pulsars and another 34 candidates awaiting confirmation. This is 27 times the number of pulsars known to astronomers before the Fermi mission launched in 2008.

April 6, 2023April 6, 2023 by David Dickinson

Brightest Gamma-ray Burst Shines Light on Milky Way Structure

GRB Burst — XMM Newton's view of the remnant of the record-setting gamma-ray burst 221009A. ESA

The brightest gamma-ray burst ever seen in 2022 still puzzles astronomers.

The more researchers look at a recent record-setting event, the stranger it gets.

The story begins on the evening of October 9^th, 2022, when NASA’s Neil Gehrels Swift orbiting observatory detected a strong X-ray outburst. The source was in the direction of the constellation of Sagitta the Arrow along the galactic plane, suggesting a source in our own Milky Way galaxy. Follow-up observations from NASA’s Fermi Gamma-Ray Space Telescope and the Earth-based European Southern Observatory’s Very Large Telescope however, soon revealed that the source was much more distant, emanating from a gamma-ray burst lying beyond our galaxy. This outburst only appeared to have happened along our line of sight as seen through the plane own galaxy from our Earthbound perspective.

March 17, 2023March 17, 2023 by Evan Gough

The Universe Sparkles in Gamma Rays in this New NASA Animation

Cosmic fireworks, invisible to our eyes, fill the night sky. We can get a glimpse of this elusive light show thanks to the Large Area Telescope (LAT) aboard NASA’s Fermi Gamma-ray Space Telescope, which observes the sky in gamma rays, the highest-energy form of light. Image Credit: NASA’s Marshall Space Flight Center/Daniel Kocevski

We’ve come a long way since gamma rays were discovered.

The late 1800s and early 1900s were a time of great scientific advancements. Scientists were just getting a handle on the different types of radiation. Radium featured prominently in the experiments, including one by French scientist Paul Ulrich Villard in 1900.

Radium decays readily, and scientists had already identified alpha and beta radiation coming from radium samples. But Villard was able to identify a third type of penetrating radiation so powerful even a layer of lead couldn’t stop it: gamma rays.

Now we have a gamma ray detector in space, and it’s showing us how the Universe sparkles with this powerful energy.

April 9, 2021April 9, 2021 by Scott Alan Johnston

Jupiter Could Make an Ideal Dark Matter Detector

NASA/JPL-Caltech/SwRI/MSSS/Kevin M. Gill (wikimedia commons)

So, you want to find dark matter, but you don’t know where to look? A giant planet might be exactly the kind of particle detector you need! Luckily, our solar system just happens to have a couple of them available, and the biggest and closest is Jupiter. Researchers Rebecca Leane (Stanford) and Tim Linden (Stockholm) released a paper this week describing how the gas giant just might hold the key to finding the elusive dark matter.

December 23, 2019December 23, 2019 by Evan Gough

Halo Around a Pulsar could Explain Why We See Antimatter Coming from Space

Astronomers have been watching a nearby pulsar with a strange halo around it. That pulsar might answer a question that’s puzzled astronomers for some time. The pulsar is named Geminga, and it’s one of the nearest pulsars to Earth, about 800 light years away in the constellation Gemini. Not only is it close to Earth, but Geminga is also very bright in gamma rays.