Archive for November, 2008
Nov
22
2008
The Bringer of Light
For the past few months I have been really looking forward to Venus 1 making a welcome return to the evening sky. So when I glanced out of the front window at around 17:45 UT on Friday and saw two bright points of light shining through the broken clouds - I knew instantly that I was looking at Jupiter and Venus.
I took this 3.2 second exposure in JPEG mode using a lens focal length of 70mm with an f/stop of 5.6 at ISO 100. The white balance was set to daylight and I purposely turned noise reduction off. Venus can be seen brushing closer to the horizon while Jupiter sits slightly higher in the sky.
The final image shown above was post processed in Photoshop CS2 where I adjusted the black and white points as well as the colour balance. To add some depth to the shot I duplicated the balanced layer and set it’s blending mode to lighten. I then applied a gaussian blur of 25 pixels to it which I then faded to 33%. The reason for doing this was that I wanted a shot that looked like it had been taken through a fog filter. I personally think this adds a liitle atmosphere to the picture. The final touch was to add a little enhancement to both Jupiter and Venus and hey presto you have a subtle but nice soft focus shot of two beautiful planets.
- Since prehistoric times Venus has been venerated amongst many ancient civilizations. The Babylonians named the bright planet Ishtar, the goddess of love that would come to epitomize womanhood. Their cuneiformic texts relate observations of the planet that date back to some time around 1600 BC. The ancient Greeks, like the ancient Egyptians believed Venus to be two bodies - the morning star and the evening star. They named the morning star Phosphoros ‘The Bringer of Light’ and named the evening star Hesperos ‘The Star of the Evening’. They soon came to realize that they were one and the same. By the time of the Romans, the planet had be named Venus to honor their goddess of love. ↩
Nov
19
2008
Planet Trek
November has been a fairly non existent month as far as observing goes. The weather has offered no real respite over the past two weeks and I seriously began to wonder if I’d ever see the stars again. So when the clouds finally broke up early this morning and allowed the crystalline sky to shine through I was pretty bowled over. I was so happy that I spent the best part of fifteen to twenty minutes just gazing up at the heavens unaided.
The waning moon was high in the south east and it’s glow curbed any kind of real DSO hunting, but I was more than happy to gaze at the variegated craters and Maria of the lunar surface. I was also looking forward to taking in a long awaited view of Saturn.
I always find something quite hypnotic about observing the moon - it has a phantasmal quality that always leaves me wondering if what I’m seeing is actually real. The 25×100 binoculars that I use are better suited to DSO hunting but they still serve to give good wide field views of the moon and bring out some remarkable detail. Concentrating my efforts on the Mare Imbrium in the northern hemisphere I began my observations above the Imbrium lava flows where I could see the large rimless crater Sinus Iridium. From here I traveled over to the north east to observe the ancient and mysterious crater Plato. The 17th Century astronomer Johannes Hevelius1 referred to this magnificent crater as ‘The Greater Black Lake’.
Moving a little further south from the Mare Imbrium, towards the terminator, I could see the large crater Archimedes with it’s two smaller companions Autolycus and Aristillus flanking it in the north east. Interestingly enough, the stretch of lunar surface between Autolycus and Archimedes is the final resting place of Luna 2 after the Soviet probe crash landed there in 1959. Just north from Aristillus, I could make out the small crater Piazzi Smyth and Mons Piton, a lone mountain that rises 2.3Km from the Mare Imbrium.
Lying just a little further east I could see the impressive Apennine Mountain range that extends a huge 600Km perimeter around the south eastern rim of the Mare Imbrium. Some of the peaks here rise 5Km from the lunar surface - the last two in the chain, Mons Hadley Delta and Mons Hadley form the valley where the Apollo 15 crew made their historic landing.
West from Apennine Mountains and Archimedes I observed the small but prominent impact crater named after the Greek astronomer and philosopher Timocharis of Alexandria 2 (320BC - 260BC). A minor ray system surrounds Timocharis that places the age of the crater around one billion years old.
Traveling south west towards the eastern edge of the Oceanus Procellarum, the beautiful ray crater Copernicus, as always, offered a stunning sight. It’s complex ray system extending 800Km across the lunar surface. Turning north east of Copernicus, lying at the beginning of the Apennine Mountains sits the moderate sized crater Eratosthenes. The crater was believed to have formed around 3.2 billion years ago which marks the beginning of the lunar Erastosthenian epoch, hence the name of this crater.
Having contented myself with a short tour of the Mare Imbrium I cast my gaze on to a more distant world - Saturn. As I said earlier, my 25×100 binoculars are better suited to DSO observing than viewing planetary bodies but I thought I’d take the chance to observe the jewel of the solar system. While the view was not the best one that I have ever seen, I can at least say that I have managed to take in this year’s first Saturnian observation.
As this graceful giant rose over the eastern horizon, I could just make out the faint traces of the rings that encircle the planet and are presently almost facing edge on to us at the current time. As for viewing any of Saturn’s moons, the orange sodium haze that comes from living near an oil refinery, several large towns and the incoming misty clouds combined to reduce the percieved sky transparency. So I was bang out of luck - this time.
- Johannes Hevelius was born on the 28th of January 1611 in Gdansk Poland. Regarded as the founder of lunar topography, he spent four years of his life charting the surface of the moon. He also discovered the moon’s libration and later published the results in his Selenographia sive Lunae Descriptio. Within his life he also discovered four comets and posited his thesis that these distant objects revolved around the sun in parabolic orbits. He named the constellation Sextans in honor of his observatory after it was destroyed by fire in 1679 along with all of his instruments and books. He died on January the 28th 1687 and was buried at St. Catherines Church in Gdansk. ↩
- Born in the 4th Century BC, Timocharis was a Greek astronomer and philosopher who helped Aristillus to create the first true star catalogue that the western world had ever seen. ↩
Nov
16
2008
Magnum Opus
As the last rays of the setting sun disappeared behind the horizon on Saturday evening, I really thought I was on to a winner. The sky was absolutely spotless - the stars were were out and Jupiter could be seen blazing over in the south west. This was prime observing weather and make no mistake. So imagine how disappointed I was when I gazed out of the window two hours later to find a thin blanket of cirrostratus coating the sky.
However, my disappointment soon evaporated as I saw the waning moon rising over in the east looking all diffuse and atmospheric. This was just too tempting a target and I broke out the tripod and the a200.
The picture above was intentionally blown to capture the lunar corona and was the best of four exposures that was taken at 26mm using an ISO of 100 with an f/stop of 4.5 and a shutter speed of 10 seconds. The image was then processed in Photoshop where I adjusted the black and white points and altered the colour balance. I also applied a layer mask and applied a circular gradient set to colour dodge to bring out a little more detail in the corona.
Having taken all the corona shots that I was going to take I packed up and headed indoors to process the RAW images and console myself with a can or two of Guinness. Little did I realize what I was going to observe in the wee small hours of Sunday morning.
Glancing from the side window at about half past midnight I saw something that I have been desperate to see for a long time. A prominent lunar corona - at first I mistook it for a lunar halo, but this didn’t stop me grabbing my gear and heading out to capture a few shots.
The shot above was a 5 second exposure, again taken using 26mm at ISO 100 with an f/stop of 4.5 and the white balance set to daylight. I took 3 decent exposures but randomly chose the one above, which I might add, required very little processing in Photoshop. The white and black points were altered as was the colour balance, but otherwise the picture is presented here as is.
I was so glad that I looked out when I did, otherwise I would have missed this beautiful phenomenon. In fact I’d have traded a whole nights’ worth of observing just to see a lunar corona like this. A wonderful sight and one of the few times I was actually pleased that there was some cloud cover.
