Total Lunar Eclipse: 28 Aug 2007

Post by **weixing** » Mon Aug 20, 2007 11:17 pm

Hi,
This is a Total Lunar Eclipse reminder. There will be a total lunar eclipse on 28 Aug 2007 (next Tuesday).

Below are some timing for Singapore:
1) Moon Rise: 19:10
2) Total Eclipse Ends: 19:22 (around 2 degree above ground level)
3) Partial Eclipse Ends: 20:23 (around 17 degree above ground level)

Hope clear sky and no low cloud on the eastern horizon.

Have a nice day.

Meng Lee · Post by **Meng Lee** » Mon Aug 20, 2007 11:33 pm

Er, how do I differentiate the yellowness-redness of the moon is being due to the penumbra shadow or due to atmospheric refraction?

Post by **weixing** » Tue Aug 21, 2007 12:11 am

Hi,

Er, how do I differentiate the yellowness-redness of the moon is being due to the penumbra shadow or due to atmospheric refraction?

Penumbra?? Usually, it is very difficult to see any difference when the Moon enter the Penumbra... may be you'll be able to see a bit of shadow just before the Moon enter the umbra.

When the Moon is low, atmospheric will usually cause the Moon to be more yellowish-orange and the colour is more constant across the whole Moon. During the total lunar eclipse, the Moon will usually in deep red and dimmer compare to the effect of the atmospheric. Also, unlike the effect of atmospheric, the colour and brightness will not be constant across the Moon.

Have a nice day.

Meng Lee · Post by **Meng Lee** » Tue Aug 21, 2007 12:26 am

Total eclipse ends when the moon just rises. So from 19.22 to 20.23, we are seeing the moon moving in the penumbra shadow and gradually leaving the Earth's shadow completely. Wah, its a difficult lunar eclipse.

Meng Lee · Post by **Meng Lee** » Tue Aug 21, 2007 12:47 am

Sigh, we haven't really had a good lunar eclipse for quite some time already.

rlow · Post by **rlow** » Tue Aug 21, 2007 2:24 pm

Our local sky is still very bright from 7.10pm to 7.22pm when the actual (umbral) lunar eclipse ends. For example, Venus usually starts to get visible to the sharp observer only around 7.15-7.20pm, and it becomes obvious only around 7.30pm. And at 2 degrees above horizon, you can forget about seeing it. The penumbral lunar eclipse is not obvious to the naked eye at all, so yes, this is going to be a rather difficult eclipse to observe.

Tachyon · Post by **Tachyon** » Tue Aug 21, 2007 4:42 pm

Sorry folks, will give this a miss. Too busy observing the stock market. Heh..

echelon · Post by **echelon** » Tue Aug 21, 2007 9:35 pm

Due to the poor conditions, I won't even bother with this eclipse. A good one will come along one of these days, just need patience.

starfinder · Post by **starfinder** » Tue Aug 21, 2007 9:36 pm

Meng Lee wrote:Total eclipse ends when the moon just rises. So from 19.22 to 20.23, we are seeing the moon moving in the penumbra shadow and gradually leaving the Earth's shadow completely. Wah, its a difficult lunar eclipse.

rlow wrote:Our local sky is still very bright from 7.10pm to 7.22pm when the actual (umbral) lunar eclipse ends. ... The penumbral lunar eclipse is not obvious to the naked eye at all, so yes, this is going to be a rather difficult eclipse to observe.

I think I have to disagree with the above assessments slightly.

I think it is the Totality of the eclipse (when the Moon is 100% in the Earth's Umbra) that ends at 7:22pm, not the eclipse itself. Thereafter, from 7:22pm, the Moon will still be partially eclipsed. It will be progressively less in the Umbra until it completely enters the Penumbra at 8:23pm.

So, between 7:22pm and 8:23pm, we would be able to observe the Moon's odd bitten-out shape in the Earth's shawdow (Umbra), getting less and less eclipsed and progressively fuller. Then, voila! A full Moon at 8:23pm, albeit a very slightly dimmer one, because it will then be completely in the Earth's Penumbra. At 9:22pm, the Moon will have completely left the Penumbra.

See the timings here:
http://sunearth.gsfc.nasa.gov/eclipse/L ... Aug28T.GIF

Of course, since our sunset will be at 7:10pm on that day, and Moon rise will be at 7:09pm, it will initially be difficult to observe the Moon due to sky brightness and low Moon altitude (as rlow says). However, I think from about 7:45pm onwards, the Moon will be just about high enough in the East to see at least a "half" eclipse.

Then again, I know our Clouds will cooperate during important events...

mrngbss · Post by **mrngbss** » Tue Aug 21, 2007 10:02 pm

starfinder wrote:
Then again, I know our Clouds will cooperate during important events...

Agreed!