Super Moon

[wjfox]

Looking out of my window, the Moon is looking spectacular right now. Closest it's been to Earth in 20 years apparently...

[PeckhamRose]

Thanks so much for posting this.

MrPR got his tripod and best camera out as a result, and has been on the balcony ten mins photographing it.

Maybe will post the result tomorrow.

OK ok we all know what the moon looks like, but even so.

What a great evening with a sky full of visible stars even in London!

[mike-fitt]

It looks absolutely amazing.

[Ann]

Yes I noticed it tonight when I went to collect a takeway. No idea about the science of it all but the moon does look spectacular tonight.

Please post photo's if you can PR.:))

[aspidistra]

It was truly amazing this evening. :)

[Jah Lush]

So beautiful I took its photograph.

[katie1997]

It was so beautiful to see the moon so close to the Earth. I couldn't stop looking at it. I will remember it forever :)

[Annette Curtain]

http://4.bp.blogspot.com/_JrjU6RHk5w4/TJkO5RA7HiI/AAAAAAAAABs/e1D78HReINk/s1600/werewolf_bogoon.jpg " What Moon ? "

[PeckhamRose]

Sorry to disappoint, but MrPR says he has not got astrong enough telephoto lens. But I will persuade him to let me see the best he has and I will make a decision....!

[Huguenot]

I haven't seen it yet over my side of the world :(

Someone asked about the physics of it, so I shall share - but please don't let it detract from what is clearly a very beautiful and life-enhancing experience!

The Moon is 3,479km wide. On average it's around 380,000km away from Earth. At this particular perigee, it's 356,577km away (so about 25,000 km closer).

This means that on average it subtends an angle of 0.524 degrees to the human eye (or the equivalent of a disc 18.3mm wide - approximately equivalent to a 5 pence piece - at a distance of 2 metres).

At the current perigee it subtends an angle of 0.558 degrees to the human eye (or the equivalent of a disc 19.5mm wide - still approximately a 5 pence piece - at a distance of 2 metres).

Unfortunately this variation in size is very close to the 'achievable' maximum resolution for the human eye (which is defined by the size of the 'cone' receptors in the eye, and is 0.7mm at 2 metres for someone with perfect vision), and simply beyond it for many of us.

In layman's terms, that means that in effect the moon cannot 'be seen to be' any larger than normal.

The appearance of a large size for the moon is usually attributable to the proximity to the horizon. The closer it is to things of 'human' size, the larger our brains tell us it is.

Hopefully though, that information will only add to the effect, because it reminds us how beautiful and fallible the human mind is!

[Huguenot]

Sorry - I can actually confirm that there's absolutely no chance of seeing the distinction in size of the moon even if you have perfect vision.

That's because at night the pupil is 'fully' open to get as much light in as possible. This creates distortion in the image (because the human eye lens isn't perfect)

Hence at night the resolution of the eye is closer to 2mm at 2 metres, and hence is worse than the difference in sizes between the 'two' moons. The moon couldn't possibly have been seen to be larger at perigee.

[Jah Lush]

Ok Mr Clever Dick just enjoy it when comes around to you.