On July 13, astronauts on board the International Space Station deployed a minisatellite, a CubeSat, to study the halo of the Milky Way in search of the missing matter of the universe.
For years scientists have been confused by the mystery of "normal" matter that makes up the universe. Estimates from the earliest light in the universe when it was still 400,000 years after the Big Bang suggest that normal matter, which makes up galaxies, stars, and planets, accounts for only five percent of the universe. The rest goes to invisible dark matter (25 percent) and dark energy (70 percent) – an unknown form of energy that permeates the entire space and accelerates the expansion of the universe.
These five percent may look a little less of something that includes everything we see or observe from our telescopes, but the fact is that we have not fully grasped earthlings yet. [1
Hundreds of thousands of years after the birth of the universe, normal matter formed the gas, stars, planets, and entire galaxies. It has evolved to what we see today, but according to current mass estimates, it is only half of what should be there.
"We should now have all the matter we had when the universe was 400,000 years old," Philosopher Kaaret, HaloSat's principal investigator, said in a statement. "Where did it go?"
Scientists have long believed that the missing matter in hot gas might be present in the space between galaxies or in the galactic halos – the extended galaxy region. The theory has not been proven, but the recently launched minisatellite could provide some critical insights by examining the halo of our galaxy. In essence, the HaloSat will measure the intense X-rays that emanate from the heated gas at a whopping 2 million degrees Celsius in the galactic halo. Unlike other X-ray telescopes, it will take a broader view of the halo – about 100 square degrees at one time – and use the data collected to confirm whether it is spherical or shaped like a fried egg.
"If you remember, the galactic halo in the fried egg model will have a different brightness distribution when you look straight ahead from Earth than when you look at a broader perspective," added Keith Jahoda, a co-founder of HaloSat. "If it's in a quasi-spherical shape compared to the galaxy's dimensions, then it's expected to have more or less the same brightness in all directions."
Once the shape is determined, scientists can calculate the mass of the halo and confirm whether the theory of missing matter is true or not. The HaloSat will take a total of 90 minutes to complete a single Earth orbit, but the observations will be This will help scientists filter out solar wind X-rays that have the same spectral signature as they are trying to find and charge enough time to charge solar cells and transfer the collected data ,