Calling astronomers or any other clever bu&&ers out there

[K.Whyjelly]

Not much into astronomy but a pretty amazing view at about 0300z this morning (the 24th) has sparked a desire to know more. To set the scene I was trundling back from the States on NAT W at FL390 and at about 30w noticed a very bright light at my 11 o'clock position just coming up over the horizon (we were heading 088 degrees true at the time). Now this light as it rose higher above the horizon appeared to pulse bright white then changed to a reddish hue before going greenish and then back to white again. it also appeared to have 5 spokes emanating from it but this was probably light refracting through the windshield (??). Immediate thought was planet, but which one? Second thought (for a split second :O) as it pulsed and changed colour was "is it a UFO?". Silly, but at that time in the morning when most normal people are tucked up in bed the mind can play strange games sometimes!!!! As time went on this body rose higher in the eastern sky and became a very bright white light.

Now for any astronomers, boffs or generally clued up folk out there, this object was obviously a planet but which one? A small bet with oneself that it was Venus, but why the pulsating nature and the vivid colour changes?? Another small bet that the sun has some part to play in this. Any help, links or general advice gladly accepted.

As an aside the jet stream coming out from the US was pretty awesome as well.....165kts up the chuff from the Eastern seaboard to around 30/35w. Great for the ground speed readout ( 620kts at one stage ) not so good for ride quality though!!:bored:

[terrahead]

I'm pretty sure that is Venus, the morning star and it can often be seen producing pulsating lights of different colours when at low elevation. But I'm not an astronomer.

Got some more feedback from the boffin about my sighting described on the thread I started today (What The Heck Was That) - for more see the thread.

[Hokulea]

Well, I am an astronomer and can confirm that what you saw was almost certainly Venus. I don't know what latitude you were at, but assuming something like 70 degrees north Venus rises at around 03:30 UTC at 30W at the moment at that altitude. It would have risen slightly north of due east (about 15-20 degrees) which ties in with your observations.

Venus is currently the brightest planet in the sky (by a long way) and is quite a spectacular sight in the early morning!

The changes in colour you mention are due to atmospheric refraction. Venus reflects sunlight which is essentially white light - a mix of all the other colours. Turbulent cells in the atmosphere refract the different colours slightly different amounts, so as the cells move you see various colours. The effect is strongest when the star (or planet) is close to the horizon as you're looking through a lot more atmosphere. Usually, the effect is much smaller with planets compared to stars as they are not point sources, but it still happens.

Finally, the spokes you mention sound very much like diffraction spikes, usually seen when observing a bright star through a telescope (they come from diffraction caused by structure at the top of the telescope). Is there, by any chance, some structure in the the cockpit window, e.g., heating elements? Diffraction caused by those might explain the spokes.

[Rainboe]

I'm an amateur astronomer too, and a pilot. Venus hass been putting on exceptionally bright displays early in the morning recently- it is a stunning sight. As it rises and is still low in the sky, the flashes of colour as observed from high altitude are simply stunning. In my earlier days, I have been known to actually take avoiding action as it rose and quite suddenly popped into view- it's that impressive. Incredibly bright at the moment.

Mars is a wonderful, bright after-midnight sight. the reddish hue is unmistakeable. Near the 7 Sisters and Hyades at the moment.

[Hokulea]

I think you guys can probably understand why Venus is often mistaken for a "UFO"! It doesn't seem to happen so much now, but we used to get several calls (at an astronomical observatory) whenever Venus was putting on a show, usually from some over-excited punter wanting to know if the aliens were finally arriving.

[wing tip brakes]

Get yourself a programme REDSHIFT 5, or a later version. Tell it where you are and the programme will tell you what you're seeing

[Willows]

Also check out stellarium (http://www.stellarium.org/) It's great for seeing what's what and where.

It must be such a beautiful sight seeing the planets rise from up there. You lucky pilots! I'm so envious. Good time to see the moon now as well. It's the largest and brightest moon of 2007.

http://www.spaceweather.com/swpod2007/23oct07/perigeeapogee.jpg?PHPSESSID=7bd12ves4unnvu1sph1khgtrm5

[global707]

It would be Venus alright. I spent many a night looking at it thinking it was 1. another aircraft coming at us, 2. UFO, 3..... (Captain was always asleep!!) Even when I see it now, I always have to really beleive that itis Venus and none of the above.

Amazing sight mind you...

[K.Whyjelly]

Global 707, have to admit that my first thought like you was another aircraft with its lights on and second thought, especially with all the Close Encounters style pulsing and changing of colour was UFOs!!!:\ Bit irrational but easy to see how folks end up contacting the authorities with alien invasion stories if you don't know what this strange but enchanting sight really is.

[PaperTiger]

It would be Venus alright. I spent many a night looking at it thinking it was 1. another aircraft coming at us...Yep, been there :O .
Once when Venus was just rising and viewed through the atmosphere I was absolutely convinced it was an aircraft - it was flashing red and green lights for heaven's sake. TWR cleared us to take off right towards this 'thing' and I replied "not until that helicopter gets out of the way". Oh dear.