Sunrise from the ISS

#1
The International Space Station is moving around the Earth at a blistering 17,000 mph, so that it only takes 90 minutes to complete one orbit around the planet. That means that the ISS experiences 16 sunrises and sunsets every 24 hours. So a period of solar illumination (daytime) for them would seem to only be 45 minutes long. But it recurs over and over again throughout the 24 hour period.

What does sunrise look like from space? Here's a photo that Astroannimal took of the edge of Earth at the moment of sunrise, showing the approaching Crew Dragon a week ago.


[Image: D0v6uVMWsAE43vC.jpg]



A few days later, Astroannimal posted another series of photographs on her twitter page that she took that illustrate subsequent stages of a sunrise as the ISS passed over the Earth's terminator (the dividing line between Earth's illuminated day-half and its dark night-half).


[Image: D1LejWdXcAE7k-9.jpg]



[Image: D1Le2rdWkAYZGAJ.jpg]



[Image: D1Le7HJX0AEmSzd.jpg]



[Image: D1Le_idXgAEAGyv.jpg]


Did Little Earth help her with the photography? Annimal and Little Earth were inseparable last week, but now Little Earth seems to be lying low since he refused to return with Ripley to SpaceX down here on Earth. Maybe he fears that he's gotten himself in trouble with that scary Elon Musk. (Isn't Little Earth technically a SpaceX employee? But while Little Earth's job title was officially "Super High Tech Zero G Indicator", everyone knows that he was really a company PR guy. And he's succeeded far beyond expectations at that, turning into an international celebrity seemingly overnight.) So maybe Elon will cut him some slack and let him stay up there with Astroannimal, with whom he's struck up a relationship.
Reply
#2
Why does the first pic look upside down? Is it camera lens or me?
Reply
#3

[Image: thumbs-up.png]
Reply
#4
(Mar 13, 2019 12:32 PM)Zinjanthropos Wrote: Why does the first pic look upside down? Is it camera lens or me?

The astronauts are weightless, so 'up' and 'down' are basically meaningless. It's all just which direction your head is pointing and how you hold the camera, I guess.

The way the ISS is configured, if you proceed head-first into the station's viewing 'cupola', the Earth will be above your head. So the astronaut would be right-side up relative to the space station but upside down relative to the Earth.

We might want to say the astronaut is beneath the Earth, except that would make everything on that part of the Earth upside down. Australians seem convinced they are standing upright in Australia with the sky above them, not hanging onto the Earth's behind by their toes like bats. From Australia's frame of reference the space station is above the earth and the astronaut inside it is upside down.

It's relativity frame-of-reference stuff, though it does explain quite a bit about Australians.


[Image: D01QONxXQAAPAnw.jpg]


The first photo in the OP was taken earlier (by the same photographer Astroannimal) and isn't part of the sequence beneath. I just included it because it shows the moment the Sun first appears around the edge of the earth. The photo appears to have been taken from the normal astronaut position of head in the cupola and legs below, the position that Little Earth is in above.

The succeeding photos seem to have been taken with the camera reversed, so as to show the Earth in its conventional position 'below', creating a more normal sunrise effect. Leaving our astronaut upside down relative to the space station, essentially sitting on the roof of the cupola.


[Image: D1CHWsMWwAA_P3Z.jpg]
Reply
#5
I looked again at that 1st pic and keep seeing the Sun and what appears to clouds on the concave side of the arc presented. Shouldn’t it always be on the convex side no matter if I’m upside down or not?

A reflection?
Reply




Users browsing this thread: 1 Guest(s)