An unusual stellar explosion observed on April 27, 2013 by NASA’s Swift satellite is the brightest gamma-ray burst (GRB) ever recorded, says a multinational team of astronomers.
Optical afterglow of GRB 130427A. Image credit: J. Mats / H. Lars / H. Patrik.
The event, labeled GRB 130427A, produced a jet of matter moving close to the speed of light, which was formed when a massive star collapsed to make a black hole at its center. As a result, a blast wave caused the rest of the star to expand outwards, producing a glowing shell of debris observed as an extremely bright supernova.
GRB 130427A happened in a galaxy a quarter of the way across the Universe. Although far away, this is much closer than a typical GRB allowing astronomers to confirm for the first time that the same object can simultaneously create both a powerful GRB and a supernovae.
“We normally detect GRBs at great distance, meaning they usually appear quite faint. In this case the burst happened only a quarter of the way across the Universe meaning it was very bright. On this occasion, a powerful supernova was also produced, something we have not recorded before alongside a Read more…
This is frightening. Nature just published a study by astronomers who have reanalyzed and recalculated the estimate of asteroids that could hit Earth and it’s a lot worse than we thought. Ten times worse.
As in, researchers are now saying we are 10 times more likely to get struck by an asteroid than before. As in, scientists are saying we need to improve our early warning systems. As in, yikes.
Here’s the thing. Researchers have always had a fairly decent track record in spotting humungous asteroids that might hit Earth. That’s because NASA previously only looked for space rock 100 feet wide and bigger. But in the aftermath of the meteorite that exploded over Russia, they’re beginning to realize that smaller asteroids are still insanely powerful and damaging and desperately need to be kept track of too.
NASA’s Hubble Space Telescope has detected a new kind of stellar blast called a kilonova that’s about 1,000 times brighter than a regular nova.
A kilonova happens when a pair of compact objects such as neutron stars crash together. Hubble observed the fading fireball from a kilonova last month, following a short gamma ray burst (GRB) in a galaxy almost 4 billion light-years from Earth.
In the image at left, the galaxy in the center produced the gamma-ray burst, designated GRB 130603B. The galaxy resides almost 4 billion light-years away. A probe of the galaxy with Hubble’s Wide Field Camera 3 on June 13, 2013, revealed a glow in near-infrared light at the source of the gamma-ray burst, shown in the Read more…
Comet Pan-STARRS, which is currently dazzling the night skies in the southern hemisphere, will reach its closest approach to the Earth today, and within the next few days, it will climb above the western horizon for those living in the northern hemisphere.
Comet C/2011 L4 (Pan-STARRS) was discovered in June 2011 using the University of Hawaii’s Panoramic Survey Telescope & Rapid Response System (Pan-STARRS). Astronomers initially predicted that it would be a very bright comet, but up until last week, it was falling well short of expectations. However, as Pan-STARRS flew past the orbit of Mercury, it brightened significantly, finally living up to the astronomer’s hopes.
The comet became visible Read more…
A newly discovered asteroid the size of a football field will cruise through Earth’s neighborhood this weekend, just days after another space rock made an even closer approach to our planet.
The 330-foot-wide (100 meters) asteroid 2013 ET will miss Earth by 600,000 miles (960,000 kilometers) when it zips by on Saturday (March 9). The space rock flyby will come just days after the 33-foot (10 m) asteroid 2013 EC approached within 230,000 miles (370,000 km) of us early Monday (March 4).
When asteroid 2013 ET passes Earth, it will be at a range equivalent to 2.5 times the distance between the planet and the moon, making it too faint and far away for most stargazers to spot in the night sky. But the Virtual Telescope Project in Italy, run by astrophysicist Gianluca Masi, will webcast a live telescope view of the space rock’s flyby on Friday (March 8), beginning at 2 p.m. EST (1900 GMT). You can access the free broadcast here: http://www.astrowebtv.org.
There is no danger that 2013 ET will hit Earth, researchers say, just as 2013 EC posed no threat. But their flybys are slightly Read more…