Talk about putting a possible spin on it, from the masters of propaganda:
https://www.yahoo.com/news/china-says-earth-bound-spacelab-offer-splendid-show-041702808.html
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Need to find my tin foil hat I wore for Skylab … you may laugh, but nothing hit me!
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For Skylab, I bought an Army surplus helmet liner and painted a target on top.
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Where is it now? Will it come over us in the next few hours?
http://www.heavens-above.com/GroundTrack.aspx
I have occasionally enjoyed looking for satellites and especially showing them to kids since Sputnik-1 in 1957. http://www.heavens-above.com/ is an awesome resource. Free registration is not required but its useful because it will remember you favorite viewing locations.
The most popular satellites are the International Space Station and the “constellation” of Iridium satellites which occasionally cause a flare with a magnitude as bright as -8. A -7.9 flare will be visible over my neighborhood on Sunday night.
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I’m willing to bet big bucks that at least seven billion people will come through this event safely.
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Very cool. Interesting watching the elevation go up and down. Want to watch when just going down … fast.
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Looks like the Tiangong-1 will actually be visible from here if it has not reentered first. The low maximum elevation to the north means the Dallas area is totally safe. Oklahoma???
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The way orbital dynamics works, a satellite overflies what resembles a sine wave on the surface. When it is crossing the equator it has a large north or south component. As it reaches maximum inclination the north-south component is near zero. Meaning that it spends much of its time near either 45 degrees north or south and the greatest odds of impact are over those two bands.
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If looked at in 3D on a globe looks like the elliptical orbit it is. these 2D drawings always look weird to me,
Looking at the path, it would have to really go off course to hit North America. Which okay by me. rather it land in China.
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In the absence of an external force, an object in orbit moves in a plane. That plane is inclined relative to the equator depending upon the latitude of the launch site.
The shape of the orbit, circular or elliptical is one parameter; the inclination is another. And they are mostly independent.
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I guess my point is, when flattened out on 2D plot like this the orbit it looks like a sine wave but in if viewed looking perpendicular to the orbital plane it will appear elliptical (circle is a special case of ellipse) with the earth in the center. Of course if viewed on edge of the plane, it would appear as a line.
Flatland, published 1884 is a great book about the perception we have based on the geometry of the world we live in. Also social commentary still current relevant 134 years later.
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ESA’s prediction page: http://blogs.esa.int/rocketscience/2018/03/26/tiangong-1-reentry-updates/
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Should have kept your tin foil hat from before.
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Likely a true statement.
However, Heaven’s Above future prediction calculations do not include terms for a decaying orbit. Thus as the orbital elements of the satellite are modified due to drag, the future predictions will change. I’m not sure how often the ‘current orbital elements / ephemeris data’ are being updated for Tiangong1. I’m pretty sure C. Peat is updating the ISS data at least once a day.
Here’s a link to the live ground track: http://www.n2yo.com/satellite/?s=37820
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It worked! 
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That’s an understatement.
Everything about China that Chinese media publishes is hardly ever negative.
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Its down and we are safe!!!
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