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This is awesome. Purely out of interest, how would one go about a similar location database for arbitrary locations in space? PostGIS presumably assumes a spher

This is awesome. Purely out of interest, how would one go about a similar location database for arbitrary locations in space? PostGIS presumably assumes a spheroid planet; what if I'm tracking objects in interplanetary space? Are there any DB plugins (accessible outside of national space agencies) that can do that?

bad_alloc 9y ago
> what if I'm tracking objects in interplanetary space? I guess you'd just want to store the orbital information of that object, as it probably won't stay at a fixed position.
- askvictor 9y ago
  Indeed; does that mean such a database would need to run an n-body simulation to determine where one object is compared to another at a given time?
  - Demiurge 9y ago
    That would require arbitrary telemetry and possibly non-deterministic solution, or something like SPICE(https://naif.jpl.nasa.gov/naif/toolkit.html https://naif.jpl.nasa.gov/naif/toolkit.html) which is a bit too far outside of 'database' domain.
b34r 9y ago
X, y, z
pjc50 9y ago
http://tdc-www.harvard.edu/catalogs/sao.html http://tdc-www.harvard.edu/catalogs/sao.html Sensibly, the star catalog is arranged by apparent position from Earth. There are two kinds of motion that need to be accounted for: the precession of the earth, which affects all coordinates uniformly ( http://www.stargazing.net/kepler/b1950.html http://www.stargazing.net/kepler/b1950.html ) and "proper motion" of the stars themselves: https://en.wikipedia.org/wiki/Proper_motion https://en.wikipedia.org/wiki/Proper_motion Proper motion is rather slow. Fortunately astronomy can take measurements across the centuries. "Proper motion was suspected by early astronomers (according to Macrobius, AD 400) but a proof was not provided until 1718 by Edmund Halley, who noticed that Sirius, Arcturus and Aldebaran were over half a degree away from the positions charted by the ancient Greek astronomer Hipparchus roughly 1850 years earlier."

bad_alloc 9y ago

> what if I'm tracking objects in interplanetary space? I guess you'd just want to store the orbital information of that object, as it probably won't stay at a fixed position.

askvictor 9y ago
Indeed; does that mean such a database would need to run an n-body simulation to determine where one object is compared to another at a given time?
- Demiurge 9y ago
  That would require arbitrary telemetry and possibly non-deterministic solution, or something like SPICE(https://naif.jpl.nasa.gov/naif/toolkit.html https://naif.jpl.nasa.gov/naif/toolkit.html) which is a bit too far outside of 'database' domain.

b34r 9y ago

X, y, z

pjc50 9y ago

http://tdc-www.harvard.edu/catalogs/sao.html http://tdc-www.harvard.edu/catalogs/sao.html Sensibly, the star catalog is arranged by apparent position from Earth. There are two kinds of motion that need to be accounted for: the precession of the earth, which affects all coordinates uniformly ( http://www.stargazing.net/kepler/b1950.html http://www.stargazing.net/kepler/b1950.html ) and "proper motion" of the stars themselves: https://en.wikipedia.org/wiki/Proper_motion https://en.wikipedia.org/wiki/Proper_motion Proper motion is rather slow. Fortunately astronomy can take measurements across the centuries. "Proper motion was suspected by early astronomers (according to Macrobius, AD 400) but a proof was not provided until 1718 by Edmund Halley, who noticed that Sirius, Arcturus and Aldebaran were over half a degree away from the positions charted by the ancient Greek astronomer Hipparchus roughly 1850 years earlier."