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What would it be?

Posted: Tue Mar 27, 2012 9:13 pm
by David Webb
While I was sky watching tonight I viewed Alphard really clear, but at 21.56 UK summer time a big bright white ball shot be going towards the ground just in front of Alphard, keep in mind that in my telescope it went down, but I think seeing as things are upturned that ball thing could have gone up into sky.
I wonder if anyone else see that? would it be a shooting star? I only see the one big bright white ball, and it was quite fast going by my lens.

Posted: Tue Mar 27, 2012 9:49 pm
by David Frydman
Dear David,
It sounds like a meteor or possibly a fireball, but your scope makes things much brighter.

Was it brighter than the star?
If so by how much?
How many seconds did it take to pass through the field?
What type eyepiece were you using?
What was the focal length of the eyepiece and the telescope, in other words what was the magnification?

If your scope inverts things it was indeed going upwards.

It could have been an artificial satellite depending how long it took to cross the field.
Did it go through the centre of the field or to one side?

Regards, David

Posted: Tue Mar 27, 2012 9:58 pm
by David Webb
Hello David, in reply to the things you ask, yes it was indeed much brighter than the stars tonight, I think it was as light as Venus if not lighter, and I think I would have had chance to count up to 2 by the time it crossed my scope view, the scope is a Celestron 114 lcm, the lens was my 9mm just alone, nothing else.
It was quite a shock seeing that happen tonight, never seen anything move in any of my time viewing in any scope, so I was quite pleased to see it.
Thank you for getting back to me.

Posted: Tue Mar 27, 2012 10:10 pm
by David Frydman
It sounds most likely to be a fireball, which is a meteor about as bright as Venus or brighter.
If you count one, two quickly it is about 1/4 second.
Slowly maybe a second of time.

If you can just see the whole of the Moon in your eyepiece that is about a half degree field.

I have seen similar bright meteors in scopes.

Regards, David

Posted: Wed Mar 28, 2012 11:38 am
by Tim Chamberlain
Could it have been an Iridium perhaps?

I took a quick look on CalSky and around the time you mention there was an Iridium flare (Iridium 49) listed as in Canes Venatici:
Flare from MMA1 (Right antenna) Magnitude=-3.8mag
Azimuth= 75.3° ENE altitude= 41.5° in constellation Canes Venatici
Flare angle=0.62°
Flare center line, closest point →MapIt: Longitude=0.217°E Latitude=+51.518° (WGS84) Distance=17.7 km Azimuth= 86.8° E
Satellite above: longitude=10.7°E latitude=+52.7° height above Earth=785.3 km distance to satellite=1113.0 km
Altitude of Sun=-21.1°
And a tumbling Iridium closer to Alphard (Iridium 71):
Flashes: Irregular, interval between flashes from 2-140s
Appears 21h23m47s 10.3mag az:357.8° N horizon
at Meridian 21h25m09s 9.8mag az: 0.0° N h:5.4°
Culmination 21h31m16s 6.2mag az: 81.7° E h:57.4°
distance: 896.2km height above Earth: 771.4km elevation of Sun: -19° angular velocity: 0.48°/s
Disappears 21h33m12s 6.7mag az:142.9° SE h:35.6°
But tumbling Iridium 69 seems much closer to both Alphard and your observing time (the times given here are for my location, of course):
Flashes: Period 30 sec, only few flashes visible
Appears 21h46m46s 10.0mag az:356.6° N horizon
at Meridian 21h49m27s 8.9mag az: 0.0° N h:11.8°
Culmination 21h54m19s 5.6mag az: 83.8° E h:69.9°
distance: 818.7km height above Earth: 774.4km elevation of Sun: -22° angular velocity: 0.53°/s
Disappears 21h55m30s 5.7mag az:146.2° SE h:51.2°
There are a few other tumbling iridiums listed around the same time, but these two seem to be the closest. They are all plotted on star charts which you can find on CalSky, maybe this will help?

Best wishes,


Posted: Wed Mar 28, 2012 3:52 pm
by David Webb
Hello Tim,
Very many thanks for that report of what I see, I am keen to learn as to what a iridiums is however as I have never heard of that, I was pleased I see that last night happen in my scope, I have been keen on telescopes for a while but being a person of little knowledge of things like iridiums I am quite pleased to learn a lot more.
Thanks again,
David UK

Posted: Wed Mar 28, 2012 4:46 pm
by Tim Chamberlain
Hello David,

Iridium satellites are a type of communication satellite, and sometimes they cause bright lights in the skies. Because of their regular orbit patterns and the angle of the sun etc websites like CalSky and Heavens Above can give quite accurate prediction times for these events (as well as the ISS passes etc).

This link will explain it better than I can and has some images too which might match what you saw if it wasn't a meteor/fireball as David suggested.

Posted: Thu Mar 29, 2012 6:16 pm
by David Webb
Yes I hit your link, and I found it very rewarding, however I did not see any streaks from that bright light I see, it was just a very bright white ball, pure round, it was as bright as Venus.

Posted: Thu Mar 29, 2012 8:40 pm
by Ender Of Days
Lens flare ? I used to get simular flashes when using my old scope
It could actually be so many things !
Always interesting !


Posted: Thu Mar 29, 2012 8:48 pm
by David Frydman
I have seen a bright fireball in an 18 x 50 binocular and it was truly amazing.
A large very bright white ball flying through the field.
On balance I would think it was a fireball, but as you say it could be one of many things.
Experience helps in narrowing down the possibilities.