Astronomy/Scope

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Question
As far as what we know about distances of all stars and  planets in our galaxy outside of our own solar system how precise are we at knowing their orbits and distances from us in the grander scheme of things? Is the night sky still pretty 2 dimensional like a matt painting from our understanding or could we construct a pretty good 3D space  map?

Answer
Hi James,

We know the distances of nearby stars quite accurately, and the distances of more distant stars in our galaxy fairly accurately. Astronomers have several tools to help them, including those described here: https://heasarc.gsfc.nasa.gov/docs/cosmic/milkyway_info.html.

But you also ask about orbits. I assume you mean the orbits of exoplanets, or planets outside our solar system. In spite of observational difficulties, we currently have orbital parameters of 1164 planetary systems, 1855 planets, and 473 multiple planet systems. See the exoplanet database - http://exoplanet.eu/catalog/. As you can see, we know some of the orbital parameters to many decimal places.

Finally, you ask about the night sky. We have a fairly good 3D map of both the Milky Way and of our observable universe. See, for instance, http://www.3dgalaxymap.com/ or http://galaxymap.org/ or https://in-the-sky.org/ngc3d.php for maps of the Milky Way. We also have a pretty good 3D map of the universe through the Sloan Digital Sky Survey (SDSS), microwave background maps, and other sources. See, for instance, http://www.space.com/17010-amazing-universe-fly-through-largest-sky-map-revealed.

Hope that helps.

Prof. Janes Gort  

Astronomy

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James Gort

Expertise

Questions on observational astronomy, optics, and astrophysics. Specializing in the evolution of stars, variable stars, supernovae, neuton stars/pulsars, black holes, quasars, and cosmology.

Experience

I was a professional astronomer (University of Texas, McDonald Observatory), lecturer at the Adler Planetarium, professor of astrophysics, and amateur astronomer for 42 years. I have made numerous telescopes, and I am currently building one of the largest private observatories in Canada.

Publications
StarDate, University of Texas, numerous Journal Publications

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