Space In General

April 1st you say...?

Didn't consider that... But I think he is serious. 20 years as an astronaut is a long time. He's partipated and commanded Space Shuttle missions, done a whole bunch of research on the ground and spent a year in space. I imagine that does take its toll.
 
16-20-jupiter-auroras.jpg
Joseph DePasquale, Smithsonian Astrophysical Observatory Chandra X-ray Center

A composite image of northern lights on Jupiter caused by a solar storm.
 
SOLAR CYCLE CRASHING: Anyone wondering why the sun has been so quiet lately? The reason is shown in the graph below. The 11-year sunspot cycle is crashing:



For the past two years, the sunspot number has been dropping as the sun transitions from Solar Max to Solar Min. Fewer sunspots means there are fewer solar flares and coronal mass ejections (CMEs). As the explosions subside, we deem the sun "quiet."

But how quiet is it, really? A widely-held misconception is that space weather stalls and becomes uninteresting during periods of low sunspot number. In fact, by turning the solar cycle sideways, we see that Solar Minimum brings many interesting changes. For instance, the upper atmosphere of Earth collapses, allowing space junk to accumulate around our planet. The heliosphere shrinks, bringing interstellar space closer to Earth. And galactic cosmic rays penetrate the inner solar system with relative ease. Indeed, a cosmic ray surge is already underway. (Goodbye sunspots, hello deep-space radiation.)
 
SOLAR CYCLE CRASHING: Anyone wondering why the sun has been so quiet lately? The reason is shown in the graph below. The 11-year sunspot cycle is crashing:



For the past two years, the sunspot number has been dropping as the sun transitions from Solar Max to Solar Min. Fewer sunspots means there are fewer solar flares and coronal mass ejections (CMEs). As the explosions subside, we deem the sun "quiet."

But how quiet is it, really? A widely-held misconception is that space weather stalls and becomes uninteresting during periods of low sunspot number. In fact, by turning the solar cycle sideways, we see that Solar Minimum brings many interesting changes. For instance, the upper atmosphere of Earth collapses, allowing space junk to accumulate around our planet. The heliosphere shrinks, bringing interstellar space closer to Earth. And galactic cosmic rays penetrate the inner solar system with relative ease. Indeed, a cosmic ray surge is already underway. (Goodbye sunspots, hello deep-space radiation.)
I guess this explains why we are seeing so many Auroras over here for the past couple of years or so. But watching space-weather, the Sun doesn't look so calm. Yes, the sunspots are minimal, but there are many plasma filaments that like to eject from the Sun practically every day.
 
How tall is the landed rocket again? I saw also a slow motion clip (half?) and thought that looked a bit fast.

It does come in fast. There is no hovering or hunting around for the spot; that would require more fuel, which is better spent lifting the payload. It's basically coming in full speed, with the thrust just exactly enough to reach zero velocity at zero altitude. It throttles up and down as it needs to in order to get that result, but there's no floating down on the rocket thrust like the lunar landers did.
 
What I find even more amazing is how much control the barge must be exerting not to just shoot away from under the rocket thrust. Still agog, I am :)
 
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