PBS: “New Study Says Humans Have Never Left Earth’s Atmosphere”

From PBS:

The Earth’s atmosphere is described as a fragile coat wrapping around the planet, comparable in scale to an apple’s skin protecting the fruit. For more than half a century, even before the Apollo 16 mission captured the first ultraviolet images of Earth, researchers knew that the outermost atmospheric layer — the geocorona — extends far beyond the denser, surface-level air that we breathe.

Now, a new study from Space Physics redefines the boundaries of our planet, based on overlooked data collected at the end of the last millennium. The report concludes that the edges of the atmosphere actually extend more than 391,000 miles from the planet’s surface, about twice as far as our moon.

This doesn’t mean you can go moonwalking without a spacesuit, said Jean-Loup Bertaux, a study coauthor and planetologist. The hydrogen molecules that make up the outer atmosphere are so sparse that this region is still considered a vacuum. Any spacecraft traveling through it wouldn’t notice a thing or be slowed by drag.

It does mean, however, that humankind has yet to leave the Earth’s atmosphere. The moon, the farthest point ever reached by astronauts, orbits well within the geocorona. 

All of this challenges the way we see our planet’s borders. NASA considers a space traveler to be an astronaut when they climb higher than 50 miles above the planet’s surface. The Fédération Aéronautique Internationale, which judges world records for aeronautic travel, uses the Kármán line — set at 100 kilometers above sea level — to denote the “edge of space.”

With this new knowledge, high-powered telescopes on the moon or in Earth’s orbit will also need to account for — and filter out — the geocorona’s bright ultraviolet light when looking out into the universe. This would make it easier to scan the cosmos. 

And if those telescopes spot planets out in the galaxy with the same halo that surrounds our Earth, that light could someday be used to locate habitable planets far from our own interstellar front door.

What the researchers did

More than two decades ago, a spacecraft called SOHO — the Solar and Heliospheric Observatory — was suspended halfway between the Earth and the sun, searching the sky for a particular frequency of ultraviolet light known as Lyman-alpha radiation.

“Lyman-alpha is, basically, the color of hydrogen,” Bertaux said. It turns out that the solar system is awash in this color, given hydrogen is the most common element in the universe. As each atom of hydrogen is illuminated by the sun, it emits a Lyman-alpha glow.

Lyman-alpha lies in the far ultraviolet portion of the light spectrum, where human eyes can’t see it. But an instrument on the SOHO spacecraft called SWAN could, and did. 

Back in the 1990s, Bertaux directed SWAN’s original and primary mission: to monitor solar wind, a constant barrage of charged particles flowing out of the sun. Bertaux is now at least nominally retired, but in his “free time,” his attention floats back to some of the long-overlooked, side-project data he collected in his 55-year career. 

With Igor Baliukin, a physicist at Russia’s Space Research Institute and the study’s lead author, Bertaux delved back into images of the Earth taken by SWAN in 1996, 1997 and 1998. 

What they found

Although the existence of the geocorona was well-known even in the early 1960s, according to Bertaux, experts at the time would have estimated that it ended well inside of the lunar orbit. 

Bertaux, Baliukin and their team found the geocorona extends more than 50 times the Earth’s diameter away from the planet’s surface. 

“When the astronauts were on the moon, they were looking back at the Earth,” Bertaux said, “but they were not thinking that they were indeed inside the atmosphere of the Earth.”

Story confirmed by RT:

The Earth’s atmosphere is much bigger than previously thought, extending far beyond the Moon, a team of scientists have revealed. The amazing discovery was made thanks to data that has been sitting unexamined for over 20 years.

We now know that the atmosphere surrounding our planet stretches 630,000km (391,464 miles) away and is 50 times the diameter of Earth, thanks to the discovery and analysis of decades-old data by scientists at Russia’s Space Research Institute.

It means that the Moon is part of our atmosphere and not outside of it. In fact, it’s actually located right in the middle of our atmosphere, at an average distance of 384,400 kilometres (238,855 miles) from Earth.

“The Moon flies through Earth’s atmosphere,”explained study author physicist Igor Baliukin of Russia’s Space Research Institute.

The jaw-dropping data was collected by the NASA/European Space Agency Solar and Heliospheric Observatory (SOHO) between 1996 and 1998 and had been gathering dust in an archive since then.

SOHO unwittingly gathered the groundbreaking information when it was mapping the geocorona, the layer of hydrogen atoms located where the atmosphere merges with outer space. The thin layer glows in far-ultraviolet light which can only be seen from space and is difficult to measure.

Because of this, it was, until now, thought to be about 200,000 kilometres (124,000 miles) from Earth, as that is the point at which solar radiation pressure would override Earth’s gravity.

SOHO’s SWAN instrument has the ability to measure far-ultraviolet emissions from hydrogen atoms, allowing it to make its amazing observation of the geocorona.

“Data archived many years ago can often be exploited for new science,” SOHO project scientist Bernhard Fleck of the European Space Agency said. “This discovery highlights the value of data collected over 20 years ago and the exceptional performance of SOHO.”

Since we're on the topic of space, does anyone find any of this weird:

The fact that we (allegedly) went to the moon in the late 1960s and early 1970s but have never been back?

The fact that we (allegedly) landed on the moon using less computer power than I currently have in my cellphone but NASA now says they can't go back because they "lost the technology"?

The fact that we (allegedly) sent astronauts through the Van Allen Radiation Belt in the 1970s but now today NASA says they're trying to figure out how to actually do that for the first time.

The fact that all the telemetry data from the moon missions has been "lost"?  Recorded over like a VCR.  Oops!

So many weird things, don't you think?

And now they appear to be revising the fact that the moon sits INSIDE Earth's atmosphere.  What?  

Or how about the fact that in every other area of life and technology, things always advance forward at rapid pace!  The rate of innovation grows exponentially, see Moore's Law and computing.  Yet, NASA seems to be the only thing going backwards?  Isn't that odd?

For any of you that feel like NASA stands for "Never A Straight Answer" here are a few videos you might find interesting: