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Comment by teraflop | Hacker News Reader

The predictions have narrowed considerably since the tweet in this article was posted. This site has an up-to-date forecast: http://www.aerospace.org/cords/reentry-predictions/tiangong-...

(You may need to click through to the full-resolution image and manually refresh to see the latest updates.)

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> Based on Tiangong-1’s inclination, however, we can confidently say that this object will reenter somewhere between 43° North and 43° South latitudes.

Whew! Glad they narrowed that down some!

woaw this .png is updated in real-time http://www.aerospace.org/CORDSuploads/TiangongStoryboard.png

From 11:05 to 11:25 UTC the perigee dropped ~10km (165 to 153)

They are blocking repeated hotlinks to the .png based on referrer.

That's a surprisingly complete page, with lots of other interesting information. Currently:

"""

Reentry Information

Tiangong-1 is currently predicted to reenter the Earth’s atmosphere around April 2nd, 2018 02:00 UTC ± 7 hours.

This prediction was performed by The Aerospace Corporation on 2018 March 31.

"""

In the image on the bottom left, theres a graph that shows how much time Tiangong spends in the sun and in the shadows. Why does it seem like Tiangong spends a lot more time in sun than in the shadow when its a non polar orbit?

Imagine an orbit that went around the Earth exactly parallel to the direction of the Sun, it could be in sunlight all the time. If you tilt such an orbit a little then part of it will fall into the shadow of the Earth, but perhaps only just a small part. There are other factors at play as well, such as the geometry of the Earth's shadow against an orbit and refraction of sunsets through the Earth's atmosphere.

Maybe it is connected to the tilt of the earth? It orbits the equator rather than the ecliptic plane of the sun.

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