NASA Jet Propulsion Laboratory reported that the astronomers who work with the Space Telescope, "Spitzer", were able to conduct a more accurate calculation of the rate of increase in the history of astronomy. In other words, this swiftness is called the Hubble constant.
We live on a small planet Earth, but this does not preclude our interest in the rest of the world. But to know the size of this huge, compared to us, the world, to find out what the age and expansion rate of the universe has. More recently, you can also add the concept of "acceleration of the expansion." But the accelerated expansion of the universe, you can still stick to the linear Hubble law.
Even in the 20's of last century, Edwin Hubble, the American astronomer, was able to prove that the universe since its inception (about 13.7 billion years ago) is expanding at a certain rate, which is constant. This constant velocity was named after the astronomer. Only in the late 90's of the XX century has been found that this rate is, in fact, increases with time. Previously, the value of this rate to clarify, for example, the age of the universe, scientists can assess with a telescope "Hubble", writes "Birzhevyo leader" in the "U.S. News".
It is reported that the "Spitzer" was able to improve the result of "Hubble" almost three times and reduced uncertainty of 3%. To date, this is a huge leap in the precision cosmological measurements.
New data show that the Hubble constant is set to 74,3 ± 2,1 km per second per Mpc. These data indicate that the two galaxies that are separated by a distance of about 3 million light years (ie one Mpc), fly at nearly 74.3 kilometers per second, according to "Market Leader". Recall that a parsec is about 3.3 light years. One million parsecs means Mpc.
In a paper published in the Astrophysical Journal, the researchers explain that we were able to take advantage of the infrared "Spitzer" before "Hubble", which only works in the visible range. In total, "Spitzer" Observe for about 90 Cepheids in the Milky Way and the Large Magellanic Cloud.
As you know, Cepheids - this pulsating variable stars are a separate class with a rather precise relation between "period" and "luminosity". They are named in honor of the star Cepheus. One of the best known Cepheids is, of course, the North Star.
The period of light variation of these variable stars are directly related to their luminosity. When comparing the brightness of the Cepheids observable with "real" brightness, which is calculated based on the period, the scientists may well calculate the distance to a star, serving, so some "beacon".
Wendy Freedman, professor of astronomy, and the band is so specified distance of about 90 stars, Cepheids.
Consequently, the "Spitzer" gave scientists the ability to assess more accurately the observed brightness of Cepheids, and hence also the distance to them. "Spitzer" also helped clarify how the same is the value of the Hubble constant.
It is reported that ten years ago it was impossible to reconcile the concept of "cosmology" and "accuracy." But now we can talk about the accuracy of a few percent, which is really surprising fact.
Thanks to the new updates on the 3% of the Hubble constant, scientists will be able to figure out what and how can affect the expansion of the universe. In addition, scientists are now able to more accurately calculate the forces of dark energy, counteracting gravity, which inexplicably stretches our universe.
But what would all the same dark energy might be, scientists by clarifying the value of the Hubble constant, can use it to study the data on the CMB that are derived probe WMAP. Thus, scientists have some independent assessment of the force with which the dark energy and counteracts gravity, pushing, so the universe more and more widely.
It is important to note that in the previous week space telescope "Hubble" was an image very distant galaxies that formed after the Big Bang, after which, by assumption, and there was our universe.