Monday, 13 January 2014

The Plough

The Plough (right) also known as the Big Dipper is possibly one of the most recognised parts of the sky , with its saucepan shaped arrangement of stars. Its important for finding the Pole star. If you go to the far side of the saucepan and trace the last two stars up you will come to Polaris, which isn't as bright as you would think. The Little Dipper shown on the left has the handle of the saucepan curving in the opposite direction to the Big Dipper

Looking at all these stars its hard to imagine that they are so far away.

1.Dubhe - the second brightest star in the Big Dipper and is the main pointer to the pole star, Polaris. It is a giant star approx 123 light years away
2.Merak- another star pointing to Polaris. It is 2.7 times more massive than our sun. 79.7 light years away
3. Phad- 83.2 light years away.
4. Megrez- the dimmest star of the seven stars in the plough. . It is 14 times brighter than the sun though
5. Alioth - the brightest star in the big dipper and 31st brightest in then whole sky. It is 82 light years away from Earth
6.Mizar/ Alcor- consisting of the four star system of Mizar and the double star system of Alcor. Only two stars out of the six are visible to the naked eye
7.Alkaid - the last star in the handle and the third brightest in the group. It is about 10 million years old.

bearing in mind that one light year =5878625541248(miles) very hard to comprehend  
Polaris although not a member of the Plough constellation it is an important star in which all others revolve. The Big Dipper points to this star (shown above)

The Big and Little Dipper are moving clusters and are travelling in the same direction as the earth

Thursday, 2 January 2014

Very early morning

Its been quite a while since i have had an opportunity to get out, so with the weather being poor at night an early morning slot came up. According to the weather forecast it was supposed to be clear with only a slight wind ideal for night sky photography.

So i managed to get up for 4.45 am and was out of the house by 5.15 am and as the location was local i managed to get set up by 5.30 giving me about 2 hours before the sun came up. For once the weather forecast was correct unlike the many nights I have looked out only to see rain , cloud cover or strong winds. Once my eyes had adjusted to the dark which took about 10 mins I was in place and camera gear set up. Then it happened cloud moved in quickly from the east, but not total cloud cover allowing for some photograph.

The location chosen was down at a local farm, I know for a visit the day before where some of the equipment was located, such as the combine harvester, as I wanted to use them in the foreground. Luckily they hadn't been moved , so I moved around with a red light.Its surprising how much you can see when you get your eyes adjusted, a good job as there was plenty of obstacles to negotiate.

Even in light wind its best to use a tripod which is weighted down, the good thing about Monfrotto tripods is that they have a place to hook a bag directly under the centre column. I had already checked the battery before coming out, its surprising how many don't and they run out of power at an interesting time , I had mounted the Tokina 11-16 mm lens on my Nikon D7000 and preset the ISO to 1600. Then it was a question of using the longish shutter speed to capture some stars. It was a different sky to the night sky I knew, so i just used compass points as guides.

Well before the sun came up the clouds started to reflect the warm glow of the sun which made this a magical time, well worth getting up for. At 5am its also a good time for reduced light pollution as many people are not awake, but when i packed up you could see the amount of lighting that was being used.

All in all a good early morning session, different to the night sessions as you are always up again time with the sun due to rise so its important to get set up quickly and know what you want to photograph.

Now Father Christmas has been very good to me this year and I hope to use some new equipment very soon weather permitting. I am still looking for that dark site, many people have suggested this and that but none are really suitable as its not truly dark, saying that very few sites are.