torsdag 28 oktober 2010

Gaps in a grey month

The last couple of weeks have been hard for enthusiastic night-time photographers in the north (for instance like me...), with an ever present thick grey cover of clouds dominating the sky.

Recently, however, a small gap in the otherwise grey month offered a fantastic view of the northern lights - here shining directly in through my window.

Other times, the cloud cover has offered the view of some optical phenomena, like in this case, a classic 22 degree lunar halo, where the Moon and brilliant Capella at mag -0.48 (just above the Moon) manage to shine through the clouds.

22 degree lunar halo

tisdag 12 oktober 2010

Northern Lights - The Winter Season is here !

Even if the autumn already has offered some nice northern lights, it is something very special to experience the first northern lights after the first snow of the season has fallen. At least to me, it somehow marks the beginning of the polar darkness period (mørkertiden in Norwegian) - my absolute favourite time of the year when everything gets more quiet, darker and more beautiful in so many ways.

Yesterday, both the snow and the northern lights arrived:

First snow of the winter + Auroras

lördag 2 oktober 2010

Comet on its way to Earth

A very interesting short-periodic comet (103P/Hartley 2) is currently on its way to the inner solar system in high speed, and will, according to magnitude predictions, most likely reach naked-eye visibility during the autumn. On November 20, the comet will pass the Earth at a "mere" distance of 18 million km, which makes this comet one of the closest that has ever passed by our planet!

Below, I will post regular updates about the comet during the year:

4 November 2010

Today is a unique day in the study of the comet - NASAs EPOXI mission will fly pass comet Hartley at a distance of only 700 kilometer ! As a ground-based observer, however, I am confined to my own back-yard and managed to get these images using a guided DSLR with a 300mm lens while waiting for the clos-up pictures from EPOXI.

The large green coma and the faint tail can be seen clearly in the pictures. The comet is now to be found in the constellation Canis Minor, not far from the bright 0-magnitude star Procyon, which acts as an excellent guide-star for anyone who wants to see the comet for themselves. The comet can still be seen easily with normal 8x42 binoculars, even from moderately light-polluted areas.

29 October 2010

After a long period with rainy weather and heavy cloud-cover, I finally got another glimpse of the comet again. Despite the fact that the 57% illuminated Moon was very close in the sky to the comet (the Moon in Cancer and the comet in Gemini) it was possible to see the comet in a normal pair of binoculars using averted vision.

The comet is now to be found fairly low in the constellation of Gemini and a series of stacked 30-sec exposures reveals a very large and diffuse coma (I estimate the degree of condensation to ~D.C. 2). The outer coma was estimated to be as large as the diameter of two full moons next to eachother, so the coma is LARGE now!

29 Oct 2010: Comet Hartleys way through the constellation Gemini

11 October 2010

Still, very cloudy weather dominates here in Northern Norway, but tonight a 30 min gap of clear sky between the snow-clouds appeared and then both the comet and some northern lights could be seen. The comet has now made its way into the constellation Perseus (see map below), and is fairly diffuse with a large coma with a low degree of condensation (D.C. 2-3).

11 Oct 2010: Comet 103P/Hartley 2 is now to be found in Perseus

11 Oct 2010: The comet could be seen as a green fuzz-ball between the snowclouds and aurorae

At higher magnification the false nucleus as well as the green inner and outer coma and a faint tail can be seen!

8 October 2010

Tonight I only got a tiny gap in the cloudcover and only managed three shots during my 15-minutes long observing session. With very strong wind and no time for polar alignment, I simply just tried a 10 sec shot at high ISO (6400) in cover of the house as the comet passed by the famous double cluster.

So, not excactly optimal conditions, but I was happy to notice that the comet could be seen clearly through 8x42 binoculars in sub-optimal conditions and must have increased in brightness since last time I observed it. I had no time for any own magnitude estimates, but according to other observers, the magnitude is now somewhere around 5-6.

8 Oct 2010: Comet 103P/Hartley 2 passing the double cluster

3 October 2010

Promising news: Already now on October 3, is comet Hartley 2 well visable in a pair of standard 10x42 binoculars and offered a fine imaging opportunity when tonight it passed just below the constellation Cassiopeia (not far from Shedar, which acts as a good guide to finding the comet).

Below, the comet (glowing in green due to the presence of cyanogen gas) is passing close to NGC 281 (also known as the Pacman-nebula) - a large gasous-cloud (glowing in red):

3 Oct 2010: Comet 103P/Hartley 2 (to the left) and NGC 281 (to the right) in Cassiopeia