Friday, June 10, 2011
Total Lunar Eclipse - Morning June 16, 2011
On the morning of Thursday, June the 16th there is a total lunar eclipse visible from all of Australia (as well as Africa, Central and parts of South-East Asia). Western Australia sees all of the eclipse, and while for central and Eastern Australia twilight occurs after totality begins, a goodly chunk of the eclipse is seen.
The eclipse starts as the Moon begins its descent towards the western horizon. You have to get out of your comfy bed and into the cold of the early morning to see it, so dress warmly and have plenty of hot cocoa on hand. This is the longest eclipse since 2000, and the best since August 2007, so it is well worth getting up and braving the cold.
The eclipsed moon near Scorpius at 5:30 am local time as seen from Adelaide, SA. In the eastern states, twilight will be starting, and in WA the eclipse will be ending. Click to embiggen.
The Moon enters the darkest part of the Earth’s shadow (the Umbra) at 4:23 am on the east coast, 3:52 am for the central states and 2:23 am in Western Australia.
Over the next hour you will see the shadow slowly creep over the Moons face until the Moon is covered by the shadow of the Earth (5:23 am eastern states, 4:52 am central states and 3:23 am WA). You should see the stars becoming more visible as the Moon darkens.
What is the best way to watch the eclipse? Well, with the unaided eye to start with. The sight of the shadow crawling over the Moon will be awesome, and you can watch the sky darken and the stars pop out as the eclipse progresses. The Moon will not be completely dark, but will be a deep red colour. Unlike solar eclipses, lunar eclipses are perfectly safe to look at.
Over in the east, as twilight approaches, Jupiter, Mars and Venus form a line. Venus is close to the bright red star Aldebaran. This is a nice accompaniment to the ongoing eclipse. You may even see a satellite going over (from Adelaide the ISS passes between Mars and Venus at 6:49 am) or a meteor or two.
You can also use binoculars; the eclipse will look quite nice in binoculars, and you will be able to see the darkened part of the Moon clearly. In a telescope, you will notice that the Earth's shadow is not sharp. You can use a low power lens to see the entire Moon to best effect, or with a high power scope you can time when various craters are covered by the shadow.
Photographing the eclipse can be done with simple digital cameras. You can just point the camera through your telescope lens and press the button, that works! For binoculars though, other than at maximum eclipse the Moon is too bright and the bright part will be over exposed.
Partial Lunar eclipse as seen from Adelaide at 21:30 pm, 26 June 2010. 4" Newtonian Reflector, 20 mm Plossl eyepiece and Canon IXUS 100 IS (400 ASA, 1/15 exposure). Click to embiggen.
For photography without a telescope, you will need a tripod or something to keep the camera steady as you take the photo. You will need to take the photo on the fastest setting you can to avoid overexposure.
Most simple digital cameras have a night mode, or allow you to set the exposure for a few seconds or more , but for most of the eclipse the Moon will be so bright you should use something like a daylight setting with no flash - experiment a little the night before to find the right settings).
If your camera has a zoom setting, zoom out to the maximum optical zoom
The Moon setting at 7:00 am local time as seen from Adelaide, SA. The shadow of the Earth is moving off the Moon Click to embiggen.
Maximum Eclipse occurs at 6:13 am on the east coast, with twilight beginning. The sight of the bronze disk of the Moon hanging in a twilight sky should be pretty good. In the central states, mid eclipse is 5:42 am and in WA it is 4:13 am
In the central states, twilight brightens as the Earths shadow slips off the Moon, and in WA the total eclipse ends at 5:03 am, and the partial eclipse ends at 6:02 am.
The YouTube clip below shows an animation of the eclipse as visualised in Stellarium.
You can link to the YouTube videocast of the eclipse here. You can get more information (eg twilight times) from the eclipse section at Southern Skywatch, and here's a printable guide suitable for kids and schools.
Cloud cover predictions can be found at SkippySky.
Because twilight occurs in both the morning and evening. Today Nautical twilight started at 06:22 in the morning and will start again at 17:40 in the evening.
So now here I am in country SA, with a great view from our backyard, with your blog up on the screen...
Can't thank you enough for all you've taught me about astronomy through here. Info and facts which I've then passed on to others. You do a great service to your readers!