Tuesday, March 16, 2010

An Iridium Flare, Venus and the Moon

But not all at the same time. First, just a very young crescent Moon and Venus taken earlier tonight.

Let's zoom in a little closer.


The Moon was fairly young so I was surprised it was so visible. Next month should be even better as Venus and the crescent Moon will meet higher in the sky.

But the main event tonight was trying to photograph my first Iridium flare. Iridium satellites are used for satellite phone service. If you are in the right place at the right time, the Sun can reflect off their parabolic dishes and give a very bright flare. The brightest can be seen during the day! I saw a good one here tonight at 7:20pm (local time) and saw that the center line was only a few miles from my place so I went for it.
When observing Iridium flares, you want to be as close to the center line as possible. My townhome is only about 6.4km from the center of this flare (according to my GPS) and that costs you three magnitudes of brightness. So you really have to be sure where you are to get the best view!

Not the best picture, but here it is.


It's that bright streak right in the middle. I did center it nicely! I should have zoomed in more on the flare region, but was a little gun shy on that since it was my first try. Next time.

If you want to observe an Iridium flare, Heavens Above is the place to go. You can enter your city, but your GPS coordinates are better. Don't know your GPS coordinates? They have a map you can use to zoom in on your observing location down to the street level. When looking at the magnitudes, remember that lower numbers mean brighter flare. -8 is the brightest you can get. 0 is much dimmer but easily visible. You can click on the flare and it will show you where the center line is relative to you so you can get closer to it.

These last only a few seconds, so obviously I didn't get a second shot tonight. I have an app on my cell phone that helps map these now, so if I pay attention, I should have more good chances to get pics of these.

Reprinted with permission from the Half-Astrophysicist Blog.

2 comments:

OrbsCorbs said...

I do not have your skill and patience with the camera. When I get pictures that look like that, it's usually because I screwed up the settings.

kkdither said...

Still a very cool picture, hale. No apology or qualifying necessary.