Astronomy

Judging by the number of Twitter fanboys, I must be the only one who think Twitter is one big pile of overhyped media crap. It is waste of time being promoted to lifestyle. Its success must come from the fact that one can peek into someone else's life, and realize it's as boring and meaningless as your own.

Still, some sites really use this channel to do something creative, and provide some sort of high-speed mini-RSS feed. The Mars Phoenix Twitter channel may be interesting to keep an eye to, certainly while NASA has briefed the US President about the discovery of something huge, and more "provocative" than the discovery of water existing on the Martian surface.

A decent star atlas is obligatory if you want to observe deep sky objects. It offers a nice glance on which objects are available for observation, and an easy way of star-hopping to get to the deepsky object. When I started astronomy at the age of 13, I bought myself the Will Tirion Star Atlas 2000. It was a book with 8 pages of star charts up to magnitude 6, and an explanation of every constellation in the sky.

Magnitude 6 is rather limited - if you have a small telescope, you'll quickly find stars up to magnitude 8. Luckily, there are some astronomers who have published some star atlases online :

• Toshimi Taki's star atlas offers 12 printable A3 pages with stars up to magnitude 6.5
• Andrew Johnson offers 20 A4 printable pages of star atlas up to magnitude 7 (18000 stars), available in black & white, or in color.
• And finally, Toshimi Taki also has a star atlas up to magnitude 8.5, offering an impressive 150 page atlas, covering 88000 stars.

Last night the weather forecast predicted some clear patches in the sky, so this was a good chance to test my new Orion XT10 telescope. Around midnight, I hauled the telescope outside : not an easy job, as the scope weighs around 25 kg... I would not say the observing conditions were ideal : far from, the moon was almost full, and rising in the south-east, there was lots of high altitude cirrus clouding and only a big patch open sky, so I needed to hurry.

I had quite some problems with the Object Locator : this uses an initial calibrating procedure called the 2 star alignment procedure (2SAP). After performing this, the Object Locator indicates the manual alignment error which they amusingly call 'Warp factor'. The warp factor should normaliter be below 0.5. An initial 2SAP attempt gave me a warp factor of 26. A second one gave a warp factor of 34. Then I knew there was something wrong. The next day, I tested out the alignment calibration function in the daylight, which indicated that the telescope wouldn't transmit any vertical movement to the Object Locator. In the Problem section guide of the manual, this should occur if
- there would be a problem with the cabling
- or the tension knobs of the telescope wouldn't be turned fit enough.

Unfortunately, both of these were Ok. I decided to disassemble the scope, and study where the Intelliscope system went wrong. It quickly seemed that the altitude encoder disc, which was responsible for the vertical movement measurement, didn't moved with the telescope. Only after studying this page with assembly instructions, it seemed that an extra nylon spacer on the tension knob prevented movement of the altitude encoder disc. After removal of the spacer, the disc nicely moved along with the scope. So, I was pretty glad I sorted this out. Next weekend, better weather is forecast, so I'm keeping my hopes high...

As the Object Locator was out of order, I quickly glanced to M13 in Hercules. There was lots of hindering light from the full moon, but the 20cm Dobson nicely resolved the center of this globular cluster into all of its stars. A second object was M57, the Ring cluster in Lyra, rather awkwardly located in the zenith. The ring was nicely visible, but the central star couldn't be resolved. I guess the moon was too much of an impediment. I then tried the UHC-E filter, which gave a slightly better result, but I was disappointed, cause I expected more of this filter. Again maybe the moon... At that moment, Lyra disappeared after the clouds, which took back control over the skies.

So, a rather disappointing first tryout. There's better weather announced, and the moon will slowly move out of the way, so I hope to have a better try in the next weekend...

My current 20cm Helios Dobson telescope is now over 4 years old,and has been a true eye-opener since I upgraded from my old 114mm telescope. It offered a crystal clear view at deep-sky objects, and thanks to the high-quality finder scope, finding objects has never been that easy.

However, I recently discovered that my regular astro-shop decided to stop its astronomical activities, and thus offering its last stock on dumping prices. This computerized Orion SkyQuest Intelliscope XT10 was too beautiful to resist. It's a 25cm (10 inch) Dobson scope which is a nice upgrade from my current scope. As a bonus, it includes a laser collimator, in order to keep the telescope calibrated, and a Intelliscope Object Locator, which is a small keypad based device, which attaches to the base of the scope. It offers an easy way to locate objects by simply choosing one from a 14000-object database, and tells you how much you need to turn the scope.

Unfortunately, using the scope will be for later : we're experiencing a typical Belgian summer, which means that it has been raining for weeks...

Serious comet chasers have been watching Comet C/2007 W1 (Boattini) for some time. For awhile, it exceeded its predicted brightness but is back to cruising at normal. During the last weeks, Boattini was a southern hemisphere object… But not for long. Now its about to round the Sun and head north!

In the next couple of weeks, Boattini will slowly become visible in Belgium as a bright object in the morning sky, visible with the naked eye. Here's a finder chart.

The Universe within 1 billion Light Years is a Web-0.1 alike website which lets you explore the neighbourhood of our galaxy, with zoom functions and an explanation of the most interesting objects.

Tonight you might watch some galactical fireworks : the Geminid meteor shower peaks this night. Start watching this evening, around 10 pm local time. At first you might not see very many meteors—but be patient. The show really heats up after midnight and by dawn on Friday, Dec. 14th, there could be dozens of bright meteors per hour streaking across the sky. For the best results, watch the esastern sky in the morning hours before sundawn. Mars is in the vicinity, so that's a good beacon.

The Geminids are not ordinary meteors. While most meteor showers come from comets, Geminids come from an asteroid—a near-Earth object named 3200 Phaethon. It's a mystery how an asteroid can produce meteors, but the most common accepted theory is that Phaeton used to be a comet, and that the current asteroid is the inner iron core that remains.

More top 10 lists : here are the top 10 most beautiful astronomical pictures of 2007.

I just had a first view on comet Holmes under medium circumstances (a bit of fog, and the moon low in the east) : the object is easily visible with the naked eye, and is very easily recognizable as a non-stellar object through plain binoculars : just aim at Perseus in the north.
There is very few detail to see in the comet; Holmes just looks like a giant snowball with a gray-greenish tint. Very large and beautiful object that will get better in the next few weeks, as the moon decreases in size and brightness.