The path of a light beam is bent by the presence of mass, and a massive body can therefore act like a lens (a "gravitational lens") to distort the image of an object seen behind it. Scientists first confirmed Einstein's prediction ...
Astronomy
Nov 1, 2019
0
845
Venus is covered in a thick layer of clouds, one reason that it appears so bright in the sky. Ancient astronomers had a good idea of what (since Copernicus) we know as its orbital period; the modern measurement is that Venus ...
Space Exploration
Oct 21, 2019
1
136
Most galaxies host a supermassive black hole (SMBH) at their nucleus, one whose mass exceeds a million solar-masses. When material actively accretes onto the SMBH, associated processes can produce an active galactic nucleus ...
Astronomy
Oct 14, 2019
0
379
Scientists at the Center for Astrophysics, Harvard & Smithsonian have announced the discovery that, contrary to previously accepted knowledge, Type Ia supernovae experience light curve decline plateaus, and lengthy ones at ...
Astronomy
Oct 7, 2019
0
268
The hot outer layer of the sun, the corona, has a temperature of over a million degrees Kelvin, much more than the surface temperature of the Sun which is only about 5500 degrees Kelvin. Moreover, the corona is very active ...
Astronomy
Sep 30, 2019
39
146
Most galaxies lie in clusters containing from a few to thousands of objects. Our Milky Way, for example, belongs to the Local Group, a cluster of about fifty galaxies whose other large member is the Andromeda galaxy about ...
Astronomy
Sep 16, 2019
3
132
The Kepler satellite is famous for its discovery of thousands of exoplanets by continuously and meticulously measuring the brightnesses of over half-a-million stars for the signatures of transiting exoplanets. Less well known ...
Astronomy
Sep 4, 2019
0
79
Over 30 years ago, the Infrared Astronomy Satellite discovered that the universe contained many extremely luminous galaxies, some more than a thousand times brighter than our own Milky Way, but which are practically invisible ...
Astronomy
Aug 19, 2019
1
298
Stars greater than eight solar-masses end their lives spectacularly—as supernovae. These single-star supernovae are called core collapse supernovae because when their dense cores (at this stage composed primarily of iron) ...
Astronomy
Aug 12, 2019
0
48
In the last century, astronomers studying the motions of galaxies and the character of the cosmic microwave background radiation came to realize that most of the matter in the universe was not visible. About 84% of the matter ...
Astronomy
Aug 5, 2019
109
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