When I was in the Air Force, during training a superior would occasionally ask “tell me a little-known but interesting fact.” To me, some of the most interesting facts are about the world above us.
The Earth’s atmosphere actually extends beyond the moon. The outermost part of the atmosphere is the geocorona, and it extends almost twice as far as the moon’s orbit. I’m guessing that’s where all of our helium is escaping to (https://earthsky.org/earth/earth-atmosphere-geocorona-extends-beyond-moon?).
A solar flare can be 10 billion times more powerful than the sun’s. We think of our sun as powerful — and it is. But the scale of the universe is truly astonishing. Scientists have recently observed a solar flare (those huge jets of gas that erupt from a star’s surface) that is 10 billion times more than anything we’ve ever seen our sun produce (https://earthsky.org/space/solar-flare-10-billion-times-more-powerful-than-suns?). Good thing we’re far away.
Our galaxy is actually warped. The Milky Way has always been thought of as a flat spiral. But now astronomers have been able to produce a 3D map of our galaxy, and it’s warped and twisted. In fact, the further away from the center, the more twisted the shape becomes ( https://earthsky.org/space/milky-way-warped-twisted-study-cepheids? ). I guess it’s hard to figure out an object’s true shape when you’re part of it.
Speaking of galaxies, we’re on a collusion course with our nearest neighbor. Never take gravity for granted. Someday, the Milky Way and Andromeda will merge (or collide, if you prefer the dramatic). But don’t worry, this is not expected to happen for another 4.5 billion or so years (https://earthsky.org/space/gaia-new-insights-milky-way-andromeda-collision?).
Of course, galaxies are the only objects that collide. Astronomers have found evidence of a collision between two planets of approximately our size. This was seen in a distant solar system, street address Kepler-107. This is a clue to how often these collisions occur, and thus how our own solar system may have formed (https://earthsky.org/space/2-colliding-exoplanets-kepler-107-system?).
And so the observing continues. I can’t wait to see what we learn about black holes.