Most of what we know today about the birth of the cosmos come from astronomical observations. However, since the rapid growth of the universe, astronomers in the future will not be able to use the same method of observation as it is today.
In a trillion years from now, our Milky Way galaxy is about to join the Andromeda galaxy. Merger between two galaxies will produce a massive galaxy that may be referred to as 'Milkomeda'.
Galaxies other neighbors will likely have long since vanished from view of cosmology. Even the cosmic microwave background (CMB) that can be used to identify the possibility of a celestial body is no longer visible. So, how do astronomers study the cosmology of the galaxy Milkomeda? How do they know the origin of the universe?
According to a report published by the Harvard-Smithsonian Center for Astrophysics, astronomers will be able to unlock the secrets of the cosmos by studying the stars escape from their own galaxy, or called by Hypervelocity Stars (HVSs).
Quoted from Universe Today, June 27, 2011, HVSs derived from a binary star system or the three stars that are a little too close to the super giant black hole at the center of their galaxy. Astronomers believe that one of the stars of this system is captured by the black hole, while others launched into outer stars of the galaxy with an extremely high speed.
HVSs hurling itself is very rare, possibly only once every 10 thousand to 100 thousand years and will continue to happen for several billion years from now if given the density of stars in the galactic center.
So, how future HVS help astronomers study the origins of the universe?
First, scientists need to find a star that is made outside the limits of the galaxy's gravitational Milkomeda. After passing the limit (about 2 billion years after the trip), acceleration from a HVSs will follow the Hubble flow or 71 kilometers per second per megaparsec (1 megaparsec = 3.08568025 × 10 ^ 22 meters)
With advanced technology, future astronomers could use the Doppler shift of spectral lines and using Einstein's cosmological constant and the acceleration of the universe at large.
In addition, scientists can also use mathematical models of galaxy formation and destruction to determine the density of mass and age of the universe when Milkomeda formed. From the knowledge gained about the age of the galaxy, scientists will be able to know when the Big Bang, or phenomenon believed to be the origin of the whole universe going. (Eh)