I'm obviously a novice. I see a star in the eastern sky every night. It is quite large and impressive. How can I identify it. Thank you.

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    $\begingroup$ There should be a "canonical" answer for the "what is this star" question since the answer will normally be "use stellarium". $\endgroup$
    – James K
    Commented Apr 1, 2017 at 6:56
  • $\begingroup$ If you have an Android phone, you can use an app like Skymap and hold your phone up at the sky and it'll help you identify the star. Can require a bit of manual calibration. For other phones, there are equivalents but not Skymap as Skymap is done by Google. $\endgroup$ Commented Apr 1, 2017 at 7:45

2 Answers 2


If an astronomical object appears to be very bright, and does not appear to 'twinkle' very much, then it is probably a planet, rather than a star. Jupiter is almost on the opposite side of the Earth to the Sun right now, so it will rise in the East when the Sun is setting in the West. Since Jupiter does look like a very bright star to the naked eye, and since it is in the part of the sky that you describe, then the object that you are seeing is almost certainly Jupiter.

As for recognising actual stars, you really need to learn the layout of the constellations to some extent. This will allow you to find your way around the night sky. A useful tool for this is a program like Stellarium. This will show you the positions of stars and other astronomical objects, including the planets.


The best way to tell the difference between planets and stars is: (From here) Early astronomers were able to tell the difference between planets and stars because planets in our Solar System appear to move in complicated paths across the sky, but stars don't.

That is, if you observe the sky night after night, the stars will all appear in fixed positions with respect to each other. They will rise and set a few minutes earlier each night (an effect that is due to the Earth's motion around the Sun), but otherwise nothing will change. This is why the background stars are sometimes referred to as the "celestial sphere" -- from our point of view, it looks like the stars are "painted" onto a gigantic sphere that surrounds Earth and therefore are unable to move with respect to each other.

Planets, on the other hand, are observed to move in very complicated paths with respect to the background stars, sometimes even appearing to go "against the grain" and reverse their directions. Therefore, they are easily distinguishable from stars if you look at the sky night after night. Although ancient astronomers did not have a correct explanation for this phenomenon, we now know that the complicated motion is just a projection effect -- it is due to the fact that Earth and the other planets are physically moving in orbits around the Sun, so the planets' relative positions as seen from Earth (with respect to the fixed background stars) change as time goes on.

There are other observational differences between planets and stars too, by the way -- such as the fact that planets almost never twinkle.

Like the text said, if an object doesn't twinkle, it's most likely to be a planet. If you observe it every night, and it appears to change its position more than stars do. Although stars also change their positions, they don't change their positions in the sky as much as planets throughout the year.

Stars maintain positions relative to one another, constellations are a great to tell the difference between planets in stars. What I mean by maintaining their positions is that each night they are usually in the same pattern and usually the same distance apart in the night sky.


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