Green Flash at Sunset

[scotastro]

As the sunset a few minutes ago it produced a very bright green flash.

It is the third seen in binoculars this year from the Centre, but the first that was very very green - so much so that Helen watching without bins saw it too. Be trying for a picture next clear evening.

I was interested in this sunset as there are reports of colourful sunsets due to the Alaskan volcanoes.

Mike

GAC

Galloway Astronomy Centre

www.gallowayastro.com

[The Warthog]

Nice catch! It's definitely on my bucket list.

[algol]

lookin at sun in binos? aint that a little dangerous

[scotastro]

Good point. I should have said that care needs to be taken, don't start looking too early or you will hurt your eyes.

The green flash only occurs as the very last tiny bit of the Sun disappears, and it lasts only seconds so there is very little sunlight hitting your eyes.

Mike

[David Galvin]

I have placed a 'Green Flash' video on UK Astronomers if you would care to take a look. This was whilst on board a cruise ship as we left the dock hence the odd view through the gantry.

http://ukastronomers.com/page/login#DAVIDGALVIN/action/videos/show/54/ajax/true

[Astroman]

The green flash is not related to the volcanoes. it is solely an atmospheric refraction phenomenon. As the Sun descends from your point of view, it shines through progressively more atmosphere. If the horizon is long enough, and the atmosphere is layered in density just right, the air acts as a prism, splitting off the green part of the spectrum just as the Sun disappears. It is visible naked eye, and can be followed with binocs if GREAT CARE is taken not to observe while more than a small sliver of the solar disk is still visible.

My horizons are nowhere near long enough to witness this amazing, spurious event, but I hope someday to be well placed by an ocean to see it someday.

[Stephen Green]

I keep looking but have never had the luke to see one

Stephen

[scotastro]

Thanks for the scientific bit Astroman - I wasn't meaning to connect the two. I was just wanted to see if the sunset sky was more colourful due to the volcanic dust.

In the direction the sun sets from me is the Irish Sea and Northern Ireland so you don't need an ocean horizon to see one.

Mike

[The Warthog]

Thanks for the scientific bit Astroman - I wasn't meaning to connect the two. I was just wanted to see if the sunset sky was more colourful due to the volcanic dust.

In the direction the sun sets from me is the Irish Sea and Northern Ireland so you don't need an ocean horizon to see one.

Mike

Interesting. Can you see N. Ireland from your coast?

[scotastro]

Not from the house, the Mull of Galloway gets in the way, but the Irish coast is only 40 miles to the west.

Mike

[Astroman]

As long as your horizon is very open, you can see the green flash. I mention the ocean as ideal because of the long horizon, but also because the heat sink effect of the ocean can cause the requisite layering of the atmosphere.

Of course, I'd love to see it from the summit of Mauna Kea.

[saturn5]

Got my first green flash this year looking out over the North Atlantic.

heres a link if your interested in a couple of images.

http://stargazerslounge.com/index.php/topic,27197.0.html

Dont know about you Mike but i was kinda chuffed after i saw it.

[scotastro]

Nice pics S5 - I was really pleased when I first saw it - at first you doubt yourself as the colour is too green. I'm just waiting for another nice sunset when I can try imaging it.

Mike

[saturn5]

Cheers Mike,i was especially pleased as i actually planned it and for once it was a plan which didn't go belly up

[Ludd]

Four and a bit years down the line, and I'm checking in to report a green flash seen from near Burning Cliff in Dorset (just east of Osmington Mills).

Mrs Ludd and I had just done an all-day walk along the SW Coastal path on Saturday and as we approached the place we were staying, I realised that the setting sun was going to appear below the bands of cloud hanging in the sky over Weymouth, Chesil Beach and Portland. Sure enough the sun came out about 15 minutes before sunset, and the whole coast was lit up with a rich golden orange light. As the sun starting sinking below the horizon (the sea beyond Chesil Beach) I wondered whether this might be the moment to see my first ever green flash. Lo and behold, the very last second, or maybe second and a half, of sunlight was suddenly intensely green.

I'd watched videos of this before, but I wasn't prepared for how distinct it would be. Pretty much made my weekend, that did.