The galaxy NGC 4666 is one of the nearest starburst galaxies to us, it s visibility hindered only by the fact we see it almost edge-on. Now it has been found to host a supernova that breaks all the rules. Image Credit: ESO/J. Dietrich
A star on the edge of becoming a supernova may be metaphorically cool, but is literally very hot. Confusingly, however, a star that subsequently became a supernova has been revealed to be literally cool before it exploded, challenging much of what astronomers thought they knew about these mighty events.
Supernovas only occasionally reveal their backstory, since they almost always take us by surprise. Sometimes, however, photographs taken of a galaxy that later hosts a supernova can be searched to find the star before its dying gasp.
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A rare glimpse of a star before it exploded in a fiery supernova looks nothing like astronomers expected, a new study suggests.
Images from the Hubble Space Telescope reveal that a relatively cool, puffy star ended its life in a hydrogen-free supernova. Until now, supernovas without hydrogen were thought to originate only from extremely hot, compact stars.
The discovery “is a very important test case for stellar evolution,” says Sung-Chul Yoon, an astrophysicist at Seoul National University in South Korea, who was not involved in the work. Theorists have some ideas about how massive stars behave right before they blow up, but such hefty stars are scant in the local universe and many are nowhere near ready to go supernova, Yoon says. Retroactively identifying the star responsible for a supernova provides an opportunity to test scenarios of how stars evolve right before exploding.
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The FINANCIAL A group of astronomers has discovered 8 millisecond pulsars located within the dense clusters of stars, known as “globular clusters , using South Africa’s MeerKAT radio telescope.
According to The University of Manchester, millisecond pulsars are neutron stars, the most compact star known, that spin up to 700 times per second. This is the first pulsar discovery using the MeerKAT antennas and it comes from the synergic work of two international collaborations, TRAPUM and MeerTIME, with the findings detailed in a Monthly Notices of the Royal Astronomical Society paper published today.
Millisecond pulsars are extremely compact stars mainly made up of neutrons, and are amongst the most extreme objects in the universe: they pack hundreds of thousands of times the mass of the Earth in a sphere with a diameter of about 24 km; and spin at a rate of hundreds of rotations per second. They emit a beam of radio waves that are detected by the observer at every
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Shiny Satellites, Space Junk Blocking Our View of the Universe: Study
The study is the first to examine the overall effect of space objects on the night sky. By Edited by Gadgets 360 Newsdesk | Updated: 3 May 2021 12:18 IST
Photo Credit: Royal Astronomical Society/ Andreas Möller
Trails caused by the fifth deployment of satellites making up the Starlink constellation
Highlights
Mega-constellations include satellites such as ones launched by Starlink
Companies such as Amazon and OneWeb, too, plan to launch their satellites
Shiny satellites and space junk orbiting Earth may have increased the brightness of the night sky by more than 10 percent above the natural light levels, a new study has found, and further stated that these objects in the sky could also pose a threat to our viewing of the universe. The research, published in the Monthly Notices of the Royal Astronomical Society, a scientific journal, is the first to examine the overall effe