Posts Tagged ‘Deneb’

Monday Monday

Another clear sky early on Monday morning offered an opportunity to experiment some more with the Sony a200. After some mild processing I thought I’d post up two of the better images that I managed to take. The first one is a return to the constellations Cygnus, Lyra and Draco. Unlike the Sunday morning image, both Cygnus and Lyra are fully visible. The double star Albireo in Cygnus as well as Vega in Lyra can both be seen floating above the roof tops. Again, if you take a closer look at Cygnus you can see part of the milky way running downwards from Deneb throughout the constellation.

The second image shot, shows the constellation Auriga and Taurus. Capella1 is clearly visible as is The Pleiades just towards the upper right hand corner of the image. If you look carefully, you can make out some fantastic nebula detail that the camera has picked up. Moving to the bottom right of the image, just above the roof top behind Aldebaran you can also see the Hyades star cluster2

Unbelievably the clouds began to move in at around 02:30 UT. It happened so quickly that within ten minutes large parts of the sky were just blanketed in that ubiquitos orange and grey gloom that saw me forced to pack up and call it a night for another time.

  1. Capella is actually a non eclipsing binary system consisting of two yellow G class stars that are in the process of becoming red giants.
  2. At a distance of 151 light years, The Hyades is the nearest star cluster to the solar system. Also known as Collinder 50, the cluster contains 300 to 400 stars that share the same chemical composition, motion through space and place of origin.

Catching Photons

The sky early on Sunday morning (05.10.08) was the best I have seen in a long while. The Astroforecast Dot Org put sky transparency at about average but from where I was observing at 02:30 UT it looked a lot better than that. This wasn’t one of my usual sessions, instead it was a great chance to take my shiny new Sony a200 DSLR for a test drive, and believe me, I had no illusions that there were going to be dud shots a plenty and a lot of experimenting going on.

It’s one thing reading up on f/stops, focal length, ISOs and exposures . . . it’s another putting it all into practice. I thought I’d take small steps and start things off by trying my hand at photographing constellations. First on the agenda was Cygnus. Focusing on infinity proved to be a real pain in the neck and I probably should have had the foresight to set the focus ring on the 18mm - 70mm zoom lens earlier in the evening.

Captures were predictably awful, but I persevered. I was pleasantly surprised when I spotted Orion just rising over the roof tops to the south east at 02.44 UT. I quickly positioned the tripod and the camera and began shooting. I started off at f4.5 using ISO 800 and a 5 second exposure. I then upped this to 10 seconds and then finally 30 seconds. It was the 30 second exposure that won the day and offered up the best (albeit slightly out of focus) capture of the evening revealing both M42 (The Orion Nebula) and M43 (De Mairan’s Nebula) as well as the star Iota Orionis which forms the tip of Orion’s sword.

I returned to my original quarry of the evening - Cygnus, which was now sinking slowly towards the horizon. Using an f/stop of 3.5 and a focal length of 18mm I managed to capture this  30 second exposure at ISO 800. Not the most dramatic shot, but it’s early days. Like the Orion shot, light pollution was quite visible in this capture as was some chroma noise, but I managed to process the worst of it out in Photoshop. I should have had the foresight to take some dark frames (note to self: TAKE DARK FRAMES!).

The white giant Deneb can be clearly seen while the star fields and dust lanes of the Milky Way are just visible as they tumble down the length of Cygnus. The top of Lyra can be seen drifting slowly out of view while Vega1 hovers just above the roof tops. Over to the far right of the image can be seen the constellation Draco or as the ancient Egyptians called it Taweret which means one who is great after the goddess of the northern sky.

By about 03:20 UT the cold really was beginning to set in so I decided to put the DSLR aside, but before I called it a night I decide to do a little observing through the Bresser 10×50s. Turning the binoculars on to Orion, I took a look at M42 and what a view - just stunning. Randomly sweeping the sky, I eventually landed on Ursa Major and took a peek at The Horse and Rider i.e. the stars Mizar and Alcor. Turning towards the zenith I decided to take in another view of M31 before sweeping south on to The Pleiades and finally back to M42 in Orion.

All in all, I’m quite pleased with my first proper attempts at DSLR astrophotography but I’m sure I’ve got a long way to go yet before reaching the next level.


  1. Based upon excess emissions of infrared radiation coming from Vega, it was ascertained that there was a disk of dust around the star much like the Kupier Belt of our own solar system. Irregularities in this disk of dust also suggest that there is at least one planetary body with a mass equal to Jupiter in orbit around the star.

Not a Cloud in Sight

Saturday night was probably the best observing session that I have had in a while. The seeing was 5/5 while the sky transparency was in the region of 4/5, so not great. As always, my observing program begins with a look at the moons Jupiter. On show were from left to right Ganymede, Io and Europa. Callisto should have been about 8.7 arc minutes west from the centre of Jupiter. I’ve written it off as being down to light pollution and reduced sky transparency, but this is the second time I have failed to resolve Callisto through my 25×100 binoculars.

Moving on from Jupiter, I turned my attention to the constellation of Sagittarius, or what I could see of it from my position. My interest here, was to observe four Messier objects: M25, M24, M18 and M17. Using the 25×100s’ I successfully located M25, an open cluster of stars 2000 light years away from Earth. I wanted to clarify my find, so turned to my trusty 10×50s’ binoculars. The view of the cluster through the 7° FOV was a delightful sight, but I’m sure it would probably have been better in darker surroundings.

Although M24 is just west of M25, locating it proved a little more difficult. Also known as The Sagittarius Star Cloud, M24 is a pseudo cluster of stars some 600 light years wide. While I had placed the cluster It was extremely difficult to resolve it through the orange LP haze. The myriad of stars that were visible still delivered a beautiful sight all the same.

While I was searching for M24 a surprise satellite shot into my FOV. Now I don’t normally set out to track satellites, but a few have sprung up on me during my observations over the past month so I decided to do some checking up to find out which satellite this was. The Lacrosse 4 Rocket is the only one that fits in with my time frame and azimuth coordinates. As I’m not adept at tracking satellites I can’t be too sure how reliably this information compares with my observation.

Returning to my Messier search I began looking for M18, an open cluster not too far above M24 which also proved a little conspicuous. None the less, the view through my 10×50s’ was still a rewarding one. However, the real crown jewel of the evening was to be M17, The Omega Nebula.

A H II emission nebula between 5000 and 6000 light years from Earth and 15 light years in diameter, M17 is a fantastic sight. Even although it looked like a dim grey(ish) white smudge against the night sky through my 10×50s’ it is amazing to think that the gas in this nebula is around 800 solar masses.

The final Messier object on my list was M16, The Eagle Nebula. Technically, this open cluster is in the constellation Serpens, but it lies pretty close to The Omega Nebula so I thought I’d include it in my observations. Surrounded by a H II region known as IC 4703, the nebula lies a staggering 7000 light years away and is truly fantastic to behold.

Taking a much needed break I eventually moved my observations towards Cygnus and six objects, a mixture of stars and DSOs’. Deneb, NGC 7000, IC 5070, NGC 6960/6992/6995, Albireo and M56 in Lyra.

Turning the 25×100s’ on Deneb, a white super giant and one of the most luminous stars known, it was clear to see that it stood up to it’s reputation. The depth of stars that also surrounded this monster star was enumerable and breathtaking. From here I worked my way upwards towards NGC 7000 otherwise known as The North America Nebula 1.

Another emission nebula, distances to NGC 7000 are not precisely known. If Deneb is responsible for ionizing the gas in the nebula, estimates would place it at about 1800 light years away with a diameter of around 100 light years. The depth of stars in this area of the sky was unbelievable and completely blew me away, but unfortunately, due to transparency conditions I could’nt make out any nebulosity. My luck was also out with IC 5070 or The Pelican Nebula as it is better known. Disappointments aside, this is a truly brethtaking part of the sky and I felt as though I could have gazed upon it for hours.

Moving down Cygnus, my next target was The Veil Nebula i.e. NGC 6960/6992/6995. The remenants of an ancient supernova that exploded somewhere between 5000 to 8000 years ago, the nebula is all that remains. Though actual distances to this DSO are not known, estimates place the nebula between 1,400 and 2,600 light years away. I wasn’t overly optimistic that I could nail this faint DSO down, and how right I was. I quickly gave up the search here as I realized that my efforts would be fruitless.

My second last stop was the double star Albireo. At a distance of 380 light years from Earth, Albireo consists of a brighter yellow star and a faint blue companion. My 25×100s’ split the two stars reasonably well and I could pick out the contrasted colours of the two stars. From here the final stop was the globular cluster M56 in Lyra.

By this point my binoculars were beginning to fog up, suffice to say M56 remained quite elusive. Rather than continue to search through fogged up binoculars I broke out my 10×50s’ and reacquainted myself with some old friends while making a new one.

The Pleiades were quite high in the south east sky and I couldn’t resist a peek. Without waxing lyrical, this is one of the best views in the night sky and a simply stunning sight.

From here I moved on to M31, The Andromeda Galaxy and nearly broke my neck looking at it. Sitting almost at the zenith, this was probably one of the best views I have ever gotten of it through a pair of binoculars. Moving down from the constellation Andromeda, I decided to try my luck with the Triangulum Galaxy M33. I swept the sky a few times from Mirach in Andromeda to αTrianguli and that’s when it suddenly resolved right there in my binoculars like magic. A pale, distant ellipsoid lying some 2.9 million light years away.

After searching for this DSO earlier in the month, this was quite an achievement for me. Undoubtedly limited local light pollution at 02:30 UT in the morning was a big help. At this point, the cold began to set in, so I decided to content myself with my observational successes and call it a night.

  1. On an interesting note, while I was repositioning the binoculars on my way to NGC 7000, a small, faint meteorite passed through Lyra towards the north, just within my field of vision. At a guess I’d say it had an entrance and disappearance arc of maybe 20° to 30° with a small short tail.