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.
Continue reading “The Mystery of Cosmic Rays Deepens”Colliding Neutron Stars are the Ultimate Particle Accelerators
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.
Continue reading “Colliding Neutron Stars are the Ultimate Particle Accelerators”Watch 14 Years of Gamma-Ray Observations in This Fascinating NASA Video
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.
Continue reading “Watch 14 Years of Gamma-Ray Observations in This Fascinating NASA Video”Fermi has Found More than 300 Gamma-Ray Pulsars
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.
Continue reading “Fermi has Found More than 300 Gamma-Ray Pulsars”Brightest Gamma-ray Burst Shines Light on Milky Way Structure
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 9th, 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.
Continue reading “Brightest Gamma-ray Burst Shines Light on Milky Way Structure”The Universe Sparkles in Gamma Rays in this New NASA Animation
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.
Continue reading “The Universe Sparkles in Gamma Rays in this New NASA Animation”Jupiter Could Make an Ideal Dark Matter Detector
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.
Continue reading “Jupiter Could Make an Ideal Dark Matter Detector”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.
Continue reading “Halo Around a Pulsar could Explain Why We See Antimatter Coming from Space”Dark Matter Could Be A Source of Gamma Rays Coming from the Center of the Milky Way
There’s a lot of mysterious goings-on at the center of the Milky Way. The supermassive black hole that resides there is chief among them. But there’s another intriguing puzzle there: an unexpected spherical region of intense gamma ray emissions.
A new study suggests that dark matter could be behind those emissions.
Continue reading “Dark Matter Could Be A Source of Gamma Rays Coming from the Center of the Milky Way”When it Comes to Gamma Radiation, the Moon is Actually Brighter Than the Sun
The eerie, hellish glow coming from the Moon may seem unreal in this image, since it’s invisible to our eyes. But instruments that detect gamma rays tell us it’s real. More than just a grainy, red picture, it’s a vivid reminder that there’s more going on than meets human eyes.
It’s also a reminder that any humans that visit the Moon need to be protected from this high-energy radiation.
Continue reading “When it Comes to Gamma Radiation, the Moon is Actually Brighter Than the Sun”