Recently, scientists have made an in discovery. They found that the outer atmosphere of Earth extends much further than what they have expected. Thus, the discovery plays an essential role in space observations and space travel.
The new research revealed that the Earth's atmosphere stretches over 630,000 kilometers. It is estimated to be 50 times bigger than the diameter of our planet. Thus, people cannot breathe there. The research has been published in the Journal of Geophysical Research: Space Physics. The study was completed with help from the ESA/NASA Solar Heliospheric Observatory (SOHO) decades of observation. The observations, however, can only be done at certain times of the year.
The study lead author Igor Baliukin from Russia's Space Research Institute mentioned in a statement that "the Moon flies through Earth's atmosphere. We were not aware of it until we dusted off observations made over two decades ago by the SOHO spacecraft."
As follows, the data revealed that the exosphere of the Earth is a little bit denser compared to the interplanetary space for a compelling distance. From the moon's distance, in an average of 60,000 kilometers from the Earth, there are still 70 hydrogen atoms per cubic centimeter, and the density only drops down to less than one atom per cubic centimeters at over four times that distance. Regardless of the low density, the hydrogen interacts with the sunlight and the UV rays in particular. The emission allowed the experts to study what they called geocorona.
The presence of the diluted hydrogen or the UV glow poses zero threats to the future astronauts during their mission around the moon. However, it must be taken into account of the scientists use near-lunar observatories. Hence, the astronauts from the Apollo 16 used the first telescope on the Moon way back in 1927. They unconsciously took the first photo of the geocorona.
The co-author and the former principal investigator of SWAN which is the instrument used by SOHO to detect the geocorona said that "at that time, the astronauts on the lunar surface did not know that they were embedded in the outskirts of the geocorona."
Furthermore, the results might have an important consequence for exoplanet research when a UV glow from hydrogen in a planet's exosphere recommends the presence of water vapor closer to the surface, which is also the case for Earth, Venus, and Mars. If the signature can be detected around a planet in another star system, a potential water reservoir can be present, according to IFLScience.
