GET YOURSELF FAMILIAR WITH SPACE TERMS
Two centuries since the first asteroid, Ceres, was spotted, space rocks are becoming identified as forces that mould our planet, wiping out species or crowning them, in a brutal act of death and creation. It is popular knowledge that an asteroid or comet slammed into modern-day Mexico around 65 million years ago, leaving behind a gigantic crater and extinguishing much of the life on Earth, notably ending the long reign of the dinosaurs.
Not long ago, many people thought that comets were a sign that something bad was about to happen to them. Long ago people didn't understand about how objects in the sky moves, so the sight of a comet must have been very disturbing. There are many historical records and works of art which record the appearance of comets and link them with terrible events such as wars or plagues. Now we know that comets are lumps of ice and rock that periodically come into the center of the solar system from somewhere in its outer reaches, and that some comets make repeated trips. When comets get close enough to the sun, heat makes them start to evaporate. Jets of gas and dust form long tails that we can see from Earth. These tails can sometimes be millions of miles long.
Looking at the night sky, it is possible to see patterns made by the brightest stars, for example lines, squares and crosses. Over 2,000 years ago, the Greeks identified certain groups and patterns of stars with various animals and characters from their myths. In about AD 140, the Greek astronomer Ptolemy listed over 40 constellations, including Orion (The Hunter) and Ursa Major (the Great Bear).
1.The Moon is moving slowly away from the Earth at the rate of 3cm per year.
2.Every Star would explode if the Gravity didnot hold its material together.
3.If the Sun became a Black Hole, it would be only a few kilometers across but it could swallow the Earth.
Our solar system is comprised of nine planets(9), namely
Mercury,Venus,Earth,Mars,Jupiter,Saturn,Uranus,Neptune,Pluto. For more information
The Solar System is made up of the Sun and all the objects that spin around it, from planets and moons, to chunks of rock and huge amounts of dust.Meteorites,comets,asteroids,constellations are located in it and it also is a part of our galaxy MILKY WAY.
Stars don't last forever. Occasionally, a star bigger than our Sun will end its life in a huge explosion, called a supernova. This explosion happens because the center, or core, of the star collapses in less than a second. The outer layers of the star are blown off in the explosion, leaving a contracting core of the star after the supernova. The shock waves and material that fly out from the supernova can cause the formation of new stars. There are many beautiful images of supernova remnants, the expanding shell of gas made up of the outer layers of the original star.
Supernova last one or two years, and can shrine brighter than a whole galaxy for this time. What happens to the star after the supernova depends on how big it was to begin with. If the star was only a few tiimes bigger than the Sun, the core will shrink into a tiny neutron star only a few miles across. If the star was much bigger than the Sun, the core will shrink down to a black hole.
today's astronomers are not only collecting visible light. Stars and galaxies, and the material between them, give out radiation across the whole of the electromagnetic spectrum: radio, and millimetre waves, and infrared with wavelengths longer than visible light; ultraviolet light, X-rays and gamma-rays with shorter wavelengths. There are telescopes to collect all these different kinds of radiation.For information on Radio and Optical Telescopes
Black holes are theoretical objects. A Black Hole is an object which has such a high gravitational pull that not even light can escape through it. Hence it appears black which makes it very hard to observe directly.
Black holes may form as a result of the collapse of a very massive star at its death. In case of Black Holes, the initial star is so massive that nothing could stop its gravitational collapse. All the matter of the star's core is crushed to an infinitely small point, a singularity.
The Big Bang was an explosion of all the matter in the universe about 15,000,000,000 years ago, which was squashed into a tiny area at more than 10,000,000 0C. The matter exploded so quickly that within the hundredth of a second, the universe was as big as the Sun ! It carried on growing.
Humans in Space
According to the dates many trips were made to different parts of the universe.
It is a new site on universe-doortouniverse