Space and astronomy news
[/caption] Neutron stars have been classed as “undead”… real zombie stars. Even though technically defunct, the neutron star continues to shine – and occasionally feed on a neighbor if it gets too close. They are born when a massive star collapses under its gravity and its outer layers are blown far and wide, outshining a …
[/caption] Supernovae are among astronomers most important tools for exploring the history of the universe. Their frequency allows us to examine how active star formation was, how heavy elements have developed, and the distance to galaxies across vast distances. Yet even these titanic explosions are only so bright, and there’s an effective limit on how …
[/caption] How were the Universe’s first supermassive black holes formed? A new model of the evolution of galaxies and black holes show collisions show that colliding galaxies likely spawned black holes that formed about 13 billion years ago. The discovery fills in a missing chapter of our universe’s early history, and could help write the …
Continue reading “Colliding Galaxies Created the First Black Holes”
[/caption] Gravitation lensing – a phenomenon that falls out of Einstein’s theory of general relativity – has been observed numerous times, making for some fantastic images of rings, arcs and crosses composed of massive galaxies light years away. As the light from a background object is bent by gravity around a foreground object, multiple, magnified …
Continue reading “First Quasar Gravitational Lens Discovered (w/video)”
[/caption] Einstein started it all, back in 1915. Eddington picked up the ball and ran with it, in 1919. And in the last decade or so astronomers have used a MACHO to OLGE CASTLES … yes, I’m talking about gravitational lensing. Now LABOCA and SABOCA are getting into the act, using Einstein’s theory of general …
Continue reading “Stunning Science Using Nature’s Telescope”
[/caption] Need more evidence that the expansion of the Universe is accelerating? Just look to the Hubble Space Telescope. An international team of astronomers has indeed confirmed that the expansion of the universe is accelerating. The team, led by Tim Schrabback of the Leiden Observatory, conducted an intensive study of over 446,000 galaxies within the …
Continue reading “Hubble Confirms Cosmic Acceleration with Weak Lensing”
[/caption] What is the speed of gravity? It’s 299,792,458 m/s. Seem familiar? Yep, it’s the speed of light (in a vacuum)! How do we know that that’s the speed of gravity? Not by direct measurement, yet, but by the great success of Einstein’s theory of general relativity (GR). In general, because it is so successful, …
The formula for velocity is one of the first that you learn in physics. It is also one of the most important as it is help to solve more complex physic problems and give comprehension of other physics concepts. However it is one that can be easily misunderstood. We too often mistake speed and velocity …
First, some simple answers: space is everything in the universe beyond the top of the Earth’s atmosphere – the Moon, where the GPS satellites orbit, Mars, other stars, the Milky Way, black holes, and distant quasars. Space also means what’s between planets, moons, stars, etc – it’s the near-vacuum otherwise known as the interplanetary medium, …
There is not one, not two, not even three gravity equations, but many! The one most people know describes Newton’s universal law of gravitation: F = Gm1m2/r2, where F is the force due to gravity, between two masses (m1 and m2), which are a distance r apart; G is the gravitational constant. From this is …