You are here:

Astronomy/What did we see tonight.

Advertisement


Question
Hi. We have been sitting outside tonight watching a "star " that is emitting bright red flashes from below it, then on one side of it. I saw green ones as well. Sometimes the white centre is very bright, then goes duller and the flashing red stops. Then there is some quick activity. It stayed static in the sky as a star would. My binoculars aren't good enough for anything except to get a good look at the red flashing lights. I have seen the space station and the shuttle go over and know they move quickly and  believe that satellites do to. What would stay in one spot but emit bursts of red and sometimes green light. I mean brighter than an airplane but realllllly high in the atmosphere.  Thanks.  I think it went behind clouds so had to stop watching it.

Valerie

Answer
Hi Valerie

You don't mention what part of the sky this was in---and that makes a very big difference.  If what you saw was within about 20 degrees of the horizon, then I am pretty sure that you saw a very bright star.  When stars are lower in the sky, the atmosphere refracts the light so that they sparkle more, and sometimes they flash different colors of the spectrum, from red to orange to green and blue.  That's a main reason that most astronomers try to focus on things that are closer to straight overhead---because the layer of atmosphere to refract the light is thinner in that direction, and so we get a much clearer picture.  An object like that will look pretty much the same in binoculars as it does to the naked eye.  

But the weather makes a big difference, too.  Some nights the atmosphere is turbulent, and that makes the stars refract more.  Other nights it is quite still, and the stars don't twinkle so much then.  

Take a look again tomorrow night. If the same bright object is more or less in the same spot in the sky at more or less the same time, then it's a star, even if it isn't flashing colors quite so much.

If it is NOT there, then you almost certainly saw an airplane headed directly towards you.  This would explain why it seemed to stay in the same place in the sky for as long as it did.  And the brightest light on any airplane is the one pointing directly forward... with red and green lights on the wingtips to either side.  Where I observe, we sometimes see planes like this coming into SFO airport.  They seem to hang in the sky forever, as they make their approach.  

Hope that helps?

Let me know what you see!

Paul Wagner  

Astronomy

All Answers


Answers by Expert:


Ask Experts

Volunteer


Paul Wagner

Expertise

Astronomy and telescope making. Have made at least seven telescopes, both refractors and reflectors, and have spent 30 years looking at the nighttime sky.

©2016 About.com. All rights reserved.