Phil Hart - Under the Stars

The sky at night is not black. Dark yes, but certainly not black. I now have enough data from dark sky sites in central and western Victoria and the Ice In Space Astro Camp at Lostock in NSW to offer some comments on what makes the sky bright and how far you have to travel to get a 'dark sky'.

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Clouds wouldn't be so bad for astronomers, if they weren't so hard to forecast. But with new high resolution model output now available from the Australian Bureau of Meteorology, things are looking up a little at least. The animation above is not a real satellite picture, but rather a 'synthetic satellite loop' - a forecast of what the weather model thought the clouds would look like over a 48 hour period.

Michaels Camera Store in Melbourne are hosting an exhibition of astrophotography images taken by members of the Astronomical Society of Victoria.

The exhibition will be on in the upstairs gallery at Michaels Camera Store, corner of Elizabeth and Lonsdale Streets in Melbourne. Opening night is Friday 3rd September from 5:30-7:30pm. The exhibition will then run until Thursday 30th September during store hours, Mon-Thu 9-6pm, Fri 9-9pm, Sat 9-5pm and Sun 11-5pm.

Every March, the Astronomical Society of Victoria hosts a 'Messier Star Party' at its Leon Mow Dark Sky Site near Heathcote, to celebrate and observe the famous catalogue of deep sky objects that Charles Messier originally recorded as nuisance objects that confused him in his hunt for comets in 18th century Paris.

If you've never heard of a 'Star Party' before, this video will give you a better idea, music and all :-). I recommend enjoying it in full screen glory via philhart.smugmug.com.

These pictures of bioluminescence in the Gippsland Lakes in my gallery have proven quite popular, so it seems time to provide a story to accompany them. But this is not a short story, rather a convoluted one of fires and floods, of microscopic algae and the inspiring, remarkable and surprising beauty of nature.

At the end of a very enjoyable three days of astrophotography with a several other astronomers at the Leon Mow Dark Sky Site in Victoria (Australia), I caught a nice display of Geminid meteors. Over two or three hours, while also tending to cameras and telescopes, I spotted about 44 Geminid meteors as well as a number of other 'sporadics'. My camera also caught quite a few.

For two hours, I kept a Canon 5D mkII ticking over at ISO3200 with 8 second exposures through a 24mm f1.4 lens wide open, all on a Vixen GP-DX equatorial mount. I stacked that against a single 2 minute exposure to capture the surrounding stars and the milky way through Orion and up to Sirius and Canis Major at the top.

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It's been awhile since I started playing with night sky timelapse videos, but finding a way to share them online with better than YouTube quality has been a bit of a stretch. Enter SmugMug and their video galleries which do the job nicely.

Below are the first few videos I've put online. You can even get them in Full HD resolution via the SmugMug 'Stars in Motion' gallery.

I've spent the last week trapsing around NSW, starting at the Central West Astronomical Society's 2009 Astrofest in Parkes - home of 'The Dish' (better in HD!):

On Saturday I dragged Neil Creek, a long time and astronomically minded friend, to Heathcote. A contributing factor was that I knew we'd both enjoy pointing his brand new Canon 5DmkII at the heavens, and in particular towards Comet Lulin.

Am I jealous.. you bet :-)

This set of images compares the actual infrared satellite image for midday Saturday 13th September 2008 with forecasts made on the same day and up to 5 days ahead. The forecasts made up to 2-3 days ahead are quite accurate, so that a reasonable estimate of the astronomy prospects for a Saturday night could be made on the Thursday beforehand. While the general trends are still correct in the 5 day forecast, the details for a particular location become much less accurate.