Size of the Universe
No one knows whether the universe is finite or infinite in size. Albert Einstein described unbound the universe as 'finite but unbound' meaning that the frontiers cannot be observed even though they are definitely there.
The observable universe maybe about 10% larger than astronomers have suppose according to early result from European space agency(ESA) Hipparcos mission. Hipparcos fixed positions in the sky of one lakh stars are logged a million more with little less accuracy since 1912 the measuring ruler using for going distance in the Cosmos has been wrongly marked.
This ruler depended on the brightness of winking (rhythmically every few days ) stars called Cepheids, but the distances of the sample near to Earth, which calibrate the ruler, could only be estimated. Nearby Cepheids are typically 1000-2000 light years away, Direct measurement carried out by Hipparcos show that the Cepheids seen in other galaxies are used as a guide to their distances. Thus, all of these galaxies may now be jubged to lie even further .
Quaras, the bright, unusual objects are the most distant objects in the Universe found to date . Quaras may be as far as 16 billion light years from the Earth . Scientists can't determine the distance to a quasar by studying it's brightness. But they can determine the distance by studying the quasar's red shift. All but the nearest galaxies and all quasar's are observed to have red shifts.
Astronomers interpret the measured amounts of red shift as evidence that the Universe is expanding with every part of Universe moving away from each other.
0 Comments