Astronomers who work with the satellite making up the map of the universe presented the final set of processed project data. What you see above is the newest image of the oldest visible light in the universe – microwave radiation, which reminds us of which universe was only a few hundred thousand years after the Big Bang.
The European Space Agency launched the “Planck “In 2009, and his telescope completed data collection in 2013. Scientists released the first data set in 2013, another in 2015, and the last, “outdated” data set last week, but he will not answer all the remaining questions about the early universe.
Plank is dead, but the mission continues
During its mission, Planck measured the glow of the cosmic microwave background (CMB) with the highest accuracy. After the Big Bang, physicists believe, the universe expanded rapidly, and then it began to cool down, although we still see the consequences of this expansion today. The light, which was born approximately 380,000 years after the Big Bang, when the atoms began to capture electrons, traveled to us all this time so that scientists could measure it on Earth. The expanding universe has so strongly stretched these waves of light that they have become microwaves. This light can be observed in any direction, wherever you look, and it represents the structure of the early universe.
The glow of the microwave background is incredibly homogeneous. Although on the map it looks red-blue and spotty, these colors represent temperature differences in tiny proportions of a degree, on average, up to 2.7 degrees above absolute zero.
Why did Planck scientists release this map in 2018, if the satellite has finished collecting data in 2013? The data set for the year 2015 was limited, since the polarization data, or the direction of the light wave indicating perpendicular to the direction of its movement, were not of high quality. The latest data were revised and gave scientists more confidence in the data on polarization and temperature. But many questions about polarization still remain, reports Nature.
The CMB offers evidence in support of the current understanding of the universe, full of dark matter and dark energy. It also supports space inflation and offers a way to measure the speed with which the universe is currently expanding. The last measurement of this velocity, the “Hubble constant”, is 67.4 km / s / Mpc. This means that every 3.26 million light years of separation by a distance (megaparsec), the universe expands by 67.4 kilometers per second.
This is simply a measurement of “Planck”, which, incidentally, does not agree with other measurements made by the satellite “Gaia” or the Hubble Space Telescope, which defines the Hubble constant at 73.5 km / s / Mpc. This is an important issue in physics, so scientists are looking for other ways to confirm the Hubble constant.
Nature reports that scientists have already switched to other missions, but some fear that in the near future a mission in space dedicated to CMB will not be. Perhaps this is the end of the Planck era. But the study of the cosmic microwave background will continue.