What is black hole?

By Anonymous -


  A black hole is a region in space with a gravitational field so intense that even light can not get out. Because light can't escape, black holes can't be seen. They're detected by the difference in behaviour of stars nearer to the black hole. Stellar black holes are formed by the collapse of the centre of a massive star. This collapse also causes a supernova, or an exploding star, that blasts part of the star into space.

Comments

Post a Comment

Popular posts from this blog

Light rays from a supernova bent by the curvature of space-time around a galaxy

By -
Image
Date:April 20, 2017 Summary:Astronomers have detected for the first time multiple images from a gravitationally lensed Type Ia supernova. The new observations suggest promising new avenues for the study of the accelerated expansion of the universe, gravity and distribution of dark matter in the universe FULL STORY The light from the supernova iPTF16geu and of its host galaxy is warped and amplified by the curvature of space mass of a foreground galaxy. In the case of the point-like supernova, the light is split into four images. These have been resolved with the Hubble Space Telescope. Credit: Original image by ALMA (ESO/NRAO/NAOJ), L. Calçada (ESO), Y. Hezaveh et al, edited and modified by Joel Johansson An international research team led by Ariel Goobar at Stockholm University has detected for the first time multiple images from a gravitationally lensed Type Ia supernova. The new observations suggest promising new avenues for the study of the accelerated expansion of the Univer...
Read more

Space process

By Anonymous -
Image
Unprecedented Detail Astronomers captured these dramatic images of the remains of a 500-year-old explosion as they explored the firework-like debris from the birth of a group of massive stars, demonstrating that star formation can be a violent and explosive process too. The colors in the ALMA data represent the relative Doppler shifting of the millimeter-wavelength light emitted by carbon monoxide gas. The blue color in the ALMA data represents gas approaching at the highest speeds; the red color is from gas moving toward us more slowly. The background image includes optical and near-infrared imaging from both the Gemini South and ESO Very Large Telescope. The famous Trapezium Cluster of hot young stars appears towards the bottom of this image. Using data from the Atacama Large Millimeter/submillimeter Array (ALMA), astronomers show a stellar explosion in the Orion Nebula in unprecedented detail. Stellar explosions are most often associated with supernovae, the spectacular deaths o...
Read more

Can we see a singularity, the most extreme object in the universe?

By -
Image
Date:April 20, 2017 Source:Tata Institute of Fundamental Research Summary:Scientists have found new ways to detect a bare or naked singularity, the most extreme object in the universe. This finding has possible astrophysical implications. FULL STORY A black hole (on the left) and a naked singularity (on the right). The dashed line represents the event horizon of the black hole, which is absent in the case of a naked singularity, and the arrows represent the direction in which light rays travel. In the case of the black hole, because of the presence of an event horizon, all light rays inside it necessarily end up at the singularity. However, light rays may escape from the vicinity of a naked singularity to a far away observer rendering it visible. A team of scientists at the Tata Institute of Fundamental Research (TIFR), Mumbai, India, have found new ways to detect a bare or naked singularity, the most extreme object in the universe. When the fuel of a very massive star is spent, ...
Read more