Did I see an Iridium flare?

[Sparrow]

I wasn't imaging last night - I was at friends for a meal and just popped out for a smoke - as I looked up at the sky I noticed a bright object which from its speed I presume was a satellite - Just for a second it was much brighter than Vega but then faded considerably but was still just visible to the naked eye - it was travelling roughly South to North.

Was this an iridium flare?

[barkis]

It could well have been an Iridium Satellite.

If you have Planetarium software, Starry Night Pro. and the exact time of the event, and your location accurately set in the programme, you could probably discover which one it was.

Ron.

[JimStan]

The ISS will also flare. It has to do with the orientation of those big solar panels to the earth's surface, and whatever spot you may be standing at when everything lines up correctly.

This page might be useful. I haven't actually tried it, but a Google search brought it up.

Iridium Flares

Jim S.

[Gregski]

The typical appearance of an Iridium flare is a quick few seconds fade up from 'nothing' to Vega / Venus brightness (or more, -8 is the max?) for a few seconds with an equally quick fade off to 'nothing' or very faint. It all takes 10-15 seconds max while moving at a slow satellite pace.

The best non-planetarium website for tracking Iridium Flares is 'Heavens Above'. A simple but brilliant site to track satellites and comets. There you will find out what happened in your skies that night!

I've seen dozens of ISS passes and alas it's never flared for me. The ISS tends to be a consistent brightness (-2, -3?) until it enters Earth's shadow when it will fade (and sometimes go red) over 10-15 secs to 'nothing'.

Hope that helps,

Greg

[JimStan]

I did not say "rare" but I guess I should have. I have seen it go over several times, myself, but only one time did I actually see it flare up. And that was probably only about 2 magnitudes. But those iridium satellites can get quite bright. Probably the brightest I have seen is about -3 ( like Venus, only moving ! ) Now I wonder, has anyone else seen the ISS flare ?

Jim S.

[Alma]

Sounds like an Iridium flare to me - very bright for a few seconds then fading to virtually nothing. The ISS also passes more or less West to East rather than South-North and every time I've seen it maintains a steady brightness then, depending on how far the Sun is over the horizon, will fade very rapidly. I've never seen it flare like an Iridium satellite.

Alan

[Alma]

Just spoke with a colleague who is an expert in satellite comms. Iridium satellites have polar orbits apparently so the South-North track combined with the brightness of the flare means you can score youself an Iridium flare sighting, I think.

Alan

[Gregski]

I'd like to ask the question if anyone else has seen the ISS flare? If so how bright can it get?

Greg

[Alma]

I've seen the ISS around 30 times now and it can certainly brighten to some degree, but I wouldn't call it a flare. Doesn't rule out the possibility though. I'm pretty sure that what Sparrow saw was an Iridium flare - not just that the trajectory sounds about right; you also have to consider statistical probablity.... there are over 70 Iridium satellites in orbit and only one ISS.

Alan

[JimStan]

I'd like to ask the question if anyone else has seen the ISS flare? If so how bright can it get?

Greg

See my post #5. The short answer is "yes", but not like an iridium satellite.

[Daz1974]

I use Heavens Above app on my android tablet and it is spot on for alerting me to the ISS orbiting over me and for iridium flares. It was this that has really got me into exploring things further. Never seen the ISS flare. Typically see it in the evenings and not the early mornings and its a solid, very bright light.

According to the app there is a -3 Iridium flare (iridium 8) at 20.27 this evening roughly ESE

[xboxdevil]

I meant to look out at -8 mag iridium flare last night, it was at 10.08, alt 34 deg, direction approx ENE.

[Gregski]

Your exact location is crutial to how bright the flare will be. I think even a few miles will significantly change the magnitude of the flare so what is -8 for you is likely to be quite a bit less for anyone some distance from you. Heavens Above website will tell you where and how bright an Iridium flare will be at it's brightest.

Greg

[moonwatcher]

and there's me thiking you were all talking about "The Green Flash" before sunset.

[gcraib]

Myself and what is now an ex girlfriend saw a very bright flash in the sky one night a few years ago. We were looking roughly south and it seemed to light up the sky!

We did conclude at the time it was a satellite, very bright for a brief period and fading. It is the brightest thing I have even seen in the sky (apart from sun and maybe moon)

[Glen]

south to north it wouldn't of been an iridium, has been said they are on a polar orbit but north to south heading

Edit : i'll take it back , i'm wrong on that, sorry:o

could of sworn they only went n>s