Watching the sky with my mom tonight, she asked me what the bright star next to Mars was. I said there were no other planets in the sky (live in the southeastern US), and as we were looking at it, the "star" just faded out. The sky was completely clear of clouds. It was about 6:40 pm when the sky had gotten pretty much completely dark. Mars was about 10 degrees above the eastern horizon, and this star was about the same distance above the horizon, slightly brighter, and 10-20 degrees to the right of Mars. The object was there for at least 20 seconds or so and stationary.
Afterwards, my mom said she's seen this thing for years in the same spot in the sky from time to time, and it bothers her that she can't explain it. Is this some sort of astronomical phenomenon?
2007-12-17 16:10:08 · 6 answers · asked by Zhuo Zi 3 in Science & Mathematics ➔ Astronomy & Space
It's a plane coming head on, a spotlight, or some other artificial light source. Being close to the horizon it may have dipped into the haze (if a plane) or distant cloud and atmosphere may have obscured it (if it's a nearby light source).
2007-12-17 16:15:29 · answer #1 · answered by Anonymous · 1⤊ 0⤋
I believe what you saw was an Iridium Flare from Iridium 91 satellite.
Mars visible at 10° alt on 17/12 at 6:40pm (USA) places you around Louisiana (Latitude ~30°). At such a location, Iridium91 would have been visible at about 6:48pm, also at an altitude of 10°, which quite agrees with your observation. Check it up for yourself on www.heavens-above.com with your exact location, I can only be approximate.
I do have a small doubt considering the fact that it was completely stationery for 20seconds, slightly improbable.
The Iridium satellite constellation is a system of 66 active communication satellites with spares in orbit and on the ground. It allows worldwide voice and data communications using handheld satellite phones.
The satellites are frequently visible in the night sky as flares– typically observed as short-lived bright flashes of light, because the mirror has the correct angle towards you only for a short duration.
Next time if you see it again, check up with heavens-above promptly and you can be sure. The site tracks various satellites other than Iridiums, even the Int'l Space Station (ISS).
2007-12-17 16:29:08 · answer #2 · answered by Ankur TG 2 · 2⤊ 0⤋
That would almost certainly have been the International Space Station (ISS) that you saw. I can't get historical data, but I did a seach using Augusta Ga, and it shows the ISS being visible at relatively low altitudes in that area of the sky right around 6:40PM this week.
When the ISS is leaving it's visible orbit, it appears to fade out.
Check out Nasa Spaceflight or the link sourced for detailed info.
A VERY impressive sight to see!!
2007-12-20 07:38:17 · answer #3 · answered by XBox Parent 1 · 0⤊ 0⤋
That could be the sun reflecting off a satellite in geosynchronous orbit, that way it would be in the same place and appear not to move and the light would only be reflecting off of it for a short period of time. Just a guess though.
2007-12-17 16:15:11 · answer #4 · answered by Jon 4 · 1⤊ 0⤋
The time of day suggests a satellite entering Earth's shadow. It's still in daylight at its altitude, even though it's dark on the ground.
2007-12-17 16:49:28 · answer #5 · answered by laurahal42 6 · 0⤊ 0⤋
It might be a Stationary Satellite. You'd ONLY be able to see it briefly- because the angle of the sun illuminating it would change as the Earth turned...
2007-12-17 16:22:21 · answer #6 · answered by Joseph, II 7 · 0⤊ 0⤋