Fireball detected 6th April 2022 00:35:54 UTC

[Hughsie]

I recently acquired an Allsky camera unit and equipped it with a ZWO ASI120mm-s camera I was no longer using for guiding along with the stock fish eye lens. Still coming to terms with software and settings and identifying what is and isn’t a meteor or fireball. Fortunately my camera loves planes and satellites but there is a team in my astro club who have taken me under their wing and are more experienced and knowledgable in these things. They assure me this one is a fireball (see bottom left hand corner) and I only caught it by the skin of my teeth!

[Craney]

Is it the case that if you have an All-Sky-Camera,  then every exciting Fireball, bolide, asteroid impact is always photographed within 10 degrees of the horizon !!!!

Seems to be the case..... or is there some observational effect that makes them more common at low angles.

Has anybody got an image that shows this epic phenomena streaking right over the zenith with flames and smoke spurting out ??

It seems the  meteor/meteorite  class of objects  is pro-actively trying to avoid publicity.

Edited April 6, 2022 by Craney

[Hughsie]

3 hours ago, Craney said:

Is it the case that if you have an All-Sky-Camera,  then every exciting Fireball, bolide, asteroid impact is always photographed within 10 degrees of the horizon !!!!

Seems to be the case..... or is there some observational effect that makes them more common at low angles.

Has anybody got an image that shows this epic phenomena streaking right over the zenith with flames and smoke spurting out ??

It seems the  meteor/meteorite  class of objects  is pro-actively trying to avoid publicity.

The ones which my astro club share with me do seem to be close to the horizon. However, I have only been up and running for a few weeks and with the clouds we have had down in East Anglia, its too early to say that they are avoiding the camera.

[Ags]

Most of the sky is at the edge of the field of view. If you look at the ground, very little of it is directly below you - most of it is off to the side of course. 

[Hughsie]

5 minutes ago, Ags said:

Most of the sky is at the edge of the field of view. If you look at the ground, very little of it is directly below you - most of it is off to the side of course. 

That made me stop and think and you probably heard the penny drop when I realised how true that is.

[Pete Presland]

WOW, you nearly missed it 🙂 Looked like a beauty as well.

[Leo S]

On 06/04/2022 at 21:30, Ags said:

Most of the sky is at the edge of the field of view. If you look at the ground, very little of it is directly below you - most of it is off to the side of course. 

Or to put it another way, Earth's atmosphere can be thought of as relatively "thin film" covering Earth's surface - it's around 100 km thick. If you aim down, you are probably covering 3-5 times (my guestimate) the amount atmosphere that you would cover if you aimed straight up. The downside is that events will be much further away, and need to be much brighter due to atmospheric extinction in order to be imaged. Given the relative scarcity of very bright events, the chances are that if you do catch one, it'll be much close to the horizon than zenith.

To illustrate what is going on, I recently put together a couple of diagrams. In the first diagram (side view) I've attached to this post, I've made the atmosphere thicker that it would be in reality, but it makes it easier to see what is going on. The pink/red area represents the atmosphere covered by someone aiming a camera straight up at zenith. The green area represents the atmosphere covered with the same camera, but aimed From the horizon upwards.

The second diagram is a plan view of the same situation, looking from directly above, rather than from the side. The dots represent individual events/meteors, and I've spread them out evenly (more or less). Note how many fall in the green vs the red areas, and also how many dots appear in the green zone CLOSE to the camera vs away from it.