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Earth's Atmosphere Extends Much Farther Than Previously Thought (newatlas.com)
Contrary to general belief that Earth's atmosphere stops a bit over 62 miles from the surface, a new study based on observations made over two decades ago by the joint US-European Solar and Heliospheric Observatory (SOHO) satellite shows that it actually extends as far 391,000 miles (630,000 km) or 50 times the Earth's diameter. This makes the Moon a very high altitude aircraft. From a report: Launched on December 2, 1995 atop an Atlas IIAS launcher from Cape Canaveral Air Force Station in Florida, SOHO is parked in the first Lagrange point (L1) 930,000 miles (1.5 million km) from Earth where it has carried out studies of the Sun and the solar winds, and will continue to do so until at least 2020. From this vantage point, the observatory's Solar Wind Anisotropie (SWAN) instrument is able to measure the presence of hydrogen by looking at the Lyman-alpha line in the solar spectrum. And what works for the Sun, works for Earth. By turning SWAN on the Earth at the right times of the year, SOHO was able to detect hydrogen atoms from the atmosphere and measure how far out they extend into what space scientists call the geocorona. While the existence of the geocorona is well known -- the telescope set up by the Apollo 16 astronauts on the Moon even photographed it -- no one was sure how far out it reaches until now.
By looking at data collected by SOHO in the mid 1990s, scientists from Russia's Space Research Institute and elsewhere were able to work out the extent and density of the geocorona. What they found was that sunlight on the day side of the Earth compresses the hydrogen until it reaches a density of 70 atoms per cubic cm at an altitude of 37,000 miles (60,000 km), and on the night side it can expand out until it has a density of only 0.2 atoms per cubic cm at the distance of the Moon's orbit. According to the study leader Igor Baliukin, the geocorona is so tenuous that it poses no hazard to astronauts or spacecraft.
By looking at data collected by SOHO in the mid 1990s, scientists from Russia's Space Research Institute and elsewhere were able to work out the extent and density of the geocorona. What they found was that sunlight on the day side of the Earth compresses the hydrogen until it reaches a density of 70 atoms per cubic cm at an altitude of 37,000 miles (60,000 km), and on the night side it can expand out until it has a density of only 0.2 atoms per cubic cm at the distance of the Moon's orbit. According to the study leader Igor Baliukin, the geocorona is so tenuous that it poses no hazard to astronauts or spacecraft.
The Earth's atmosphere extends all the way to Mars, fact. The "Solar Wind" blows away parts of the upper atmosphere all the time. The magnetosphere reduces that a lot; without it we probably wouldn't have an atmosphere at all. Once they get their measurements fine enough and get a probe around Mars, they will find Earth's atmosphere there too.
Doesn't mean shit.
=^..^= all your rodent are belong to us
A proton can hit with the impact force of a baseball traveling at over one hundred miles per hour
This is halfway between misleading and wrong.
A proton can have the momentum of a 100 mph baseball, but that is not the same as having the same impact. A baseball hitting a person or machine will stop within a millimeter, transfering momentum quite effectively. A high energy particle transfers only a small fraction of its energy with each collision, which is more likely to strip the particle it hits from the body than transfer momentum. It takes a lot of material and distance to stop a high energy particle and the spray of stuff it creates. A person or spacecraft would not notice if hit by such a particle (unless maybe the spray hits an eye, camera, or memory cell, but even the initial proton collision would not affect those things).
Also, a proton with the momentum of a fast b and baseball is not simply a significant fraction of the speed of light, but essentially the fastest thing ever measured. A proton going 99.999999% the speed of light still has much less momentum than an amoeba. This is like bringing up the effects of spacecraft reentries in a discussion of the risks of speeding on a highway.