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I used an astronomy app on my phone to verify the satellites, planets, stars, meteors part.

They moved around in a non-linear fashion at will, they were intelligently operated. One of them disappeared in a flash...



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Hey that's cool. How'd they do it? I guess some sort of logic to look for movement in the image and put the stars around it?

Without have any knowledge of how that device works, detecting stars from images, their speed, and the distances are all solved problems in astronomy.

Recording a billion coordinates and some metadata doesn't sound like science fiction at all.


If you are into this kind of stuff, check out "Star walk" and especially "Solar walk" for iOS. Probably having seen these apps makes me fail at seeing the mind-blowing part of the app in submission :(

I'm amazed at people who are stupefied by software's ability to know where the stars are today, without any external sensors. They have known trajectories, it's trivial to calculate the position.

I'm not an expert, but I imagine that astronomers are pretty good at determining brightness of objects. And space stuff moves in orbits anyway.

These are my pets, they know astronomy and make applications for android.

Finally I have a justification for making an android application that will tell you where you are based upon photographing the stars.

I found the framing of the star tracking problem as a graph problem very intuitive. Now I just need a big sounding rocket to try some experiments. :)

Me too! I've also been looking for an astronomy app that's not super complex, and not like a projection of the sky, just a list: "What's in the sky tonight," ordered by most-commonly-wondered about. Like "1) If you look to the West you'll probably see Venus."

Surprised nobodies mentioned celestial sensors.

Celestial navigation by imaging the sky, and combining that data with a clock and compass.


Stellarium is one of the great under-sung feats of open-source. And it's great for learning.

A person may have learned to identify many objects in the sky. The planetarium feature (motion at various rates) makes it much easier (and faster) to comprehend how it all fits together at various times of the day and of the year. Fascinating.

For example, turn on the line of the ecliptic and watch its motion around 'due south' as the day goes by. (Wild at this time of year.) Or tell the program to 'track' a constellation (e.g. Orion) and then fast-forward by days to see how it rises/falls wrt the horizon because of the Earth's tilt. Or watch (and try to figure out) why the Moon moves all over the sky.


I can move astronomical bodies. Every time I move every astronomical body moves a bit as well!

Super simple == many people-centuries sapped from funding-strapped research.

Furthermore, astronomy is just entering a paradigm where the entire sky can be imaged multiple times per night with great optical depth. Transients are going to be the next frontier, and that is precisely what these constellations will create. A few lost satellites with improperly-documented orbits can fake optical transients.

Furthermore, radio astronomers have moved to the outback of Australia to get away from rare radio transients. A zoo of satellites is precisely something they don't need.


Plate solving - identifying constellations and deep sky objects by the relative positions of stars - is a pretty common part of astronomy software and possible on a raspberry pi. For example https://github.com/dstndstn/astrometry.net

I'm not aware of anything that can, say, identify a meteor and differentiate it from a plane or satellite, but I'm sure it's possible.


In space they still use similar methods. A different division of a company I used to work for built star trackers for satellites.

When I took astronomy classes in college, I was introduced to a very cool program called Digital Universe. It's developed by the Hayden Planetarium (the one where Neil deGrasse Tyson is Director) and comes with a module to explore the "local neighborhood" of stars.

It was used in the astronomy program for education and outreach to the general public, and one of the cool things we would do with it was have the audience identify a constellation and then zoom in to see just how disconnected the stars actually are.

It has other modules for different astronomical objects/scales. They have a free version for download on their website:

http://www.amnh.org/our-research/hayden-planetarium/digital-...


Yes, note that even the amateur astronomer didn't know he had captured the footage until ten days later when he looked at it!

Yes, note that even the amateur astronomer didn't know he had captured the footage until ten days later when he looked at it!

When I was in school two decades ago I wrote a program to scrape Iridium Flare passes from HeavensAbove, filter on time and magnitude, cross-check with cloud coverage from Weather Underground, and put good viewings in my calendar with a vibrate alarm a few minutes in advance (which synced to my Palm Pilot). It felt precognizant to walk out of a lecture and be like, "Hey look up at the sky right over there!" and we'd all see the flash.
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