Astronomers using data from NASA’s Fermi Gamma-ray Space Telescope have detected hints of periodic changes in the brightness of a so-called “active” galaxy, whose emissions are powered by a supersized black hole. If confirmed, the discovery would mark the first years-long cyclic gamma-ray emission ever detected from any galaxy, which could provide new insights into physical processes near the black hole.
Researchers using NASA’s Fermi Gamma-ray Space Telescope have discovered the first gamma-ray pulsar in a galaxy other than our own. Known as PSR J0540-6919, the object sets a new record for the most luminous gamma-ray pulsar known. The pulsar lies in the outskirts of the Tarantula Nebula in the Large Magellanic Cloud, a small galaxy that is located 163,000 light-years away.
The planet Mercury is being pelted regularly by bits of dust from an ancient comet, a new study has concluded. Comet Encke has the shortest period of any comet, returning to perihelion every 3.3 years. The dust from the comet affects Mercury’s tenuous atmosphere and may lead to a new understanding on how these airless bodies maintain their ethereal envelopes.
Orbiting a mere 3,700 miles above the surface of Mars, Phobos is closer to its planet than any other moon in the solar system. Mars’ gravity is drawing in the 17 × 14 × 11 mile body by about 6.6 feet (2 metres) every hundred years. The long, shallow grooves lining the surface of Phobos are likely early signs of its structural failure as scientists expect it to be pulled apart.
NASA’s Swift spacecraft has detected its 1,000th gamma-ray burst (GRB). A GRB is a fleeting blast of high-energy light, often lasting a minute or less, occurring somewhere in the sky every couple of days. GRBs are the most powerful explosions in the universe, typically associated with the collapse of a massive star and the birth of a black hole.
NASA’s Mars Atmosphere and Volatile Evolution (MAVEN) mission has identified the process that appears to have played a key role in the transition of the Martian climate from an early, warm and wet environment that might have supported surface life to the cold, arid planet Mars is today. Researchers have determined the rate at which the Martian atmosphere is losing gas to space via stripping by the solar wind and that the erosion increases significantly during solar storms.
One method to discover planets beyond the solar system by far is transit photometry, which measures changes in a star’s brightness when a planet crosses in front of its star along our line of sight. NASA’s Kepler Space Telescope has used this technique to become the most successful planet-hunting spacecraft to date, with more than a thousand established discoveries. Satellites carrying improved technology for all-sky surveys are now planned, missions that will tell us a great deal about alien planetary systems similar to our own.
Comet Lovejoy lived up to its name by releasing as much ethyl alcohol as in at least 500 bottles of wine every second as well as a type of sugar into space during its peak activity, according to new observations by an international team. The finding adds to the evidence that comets could have been a source of the complex organic molecules necessary for the emergence of life.
Thanks to a lucky conjunction of two satellites, a ground-based array of all-sky cameras, and some spectacular aurorae boreales, researchers have uncovered evidence for an unexpected role that electrons have in creating the dancing aurorae. Though humans have been seeing aurorae for thousands of years, we have only recently begun to understand what causes them.
Nearly all black holes come in one of two sizes: stellar mass black holes that weigh up to a few dozen times the mass of our Sun, or supermassive black holes ranging from a million to several billion times the Sun’s mass. A team led by astronomers at the University of Maryland and NASA’s Goddard Space Flight Center has found evidence for a new intermediate-mass black hole about 5,000 times the mass of our star.
© 2019 Pole Star Publications Limited