Via kottke the Milky Way Transit Authority map by Samuel Arbesman.

From Cosmic Variance a note about a paper from Bob McElrath that appeared on arXiv. The paper is too technical for me, but a new perspective on something that puzzles scientists for so long is always a good thing…

It must have been a great show…

Yesterday I went to the observatory for another night of observing with Doctor and the Kid. I had planned to capture data for a light curve of Wasp-1 but clouds in the beginning of the night, and the usual delays that always happen made me change my mind and I ended up with a night of technical refinements, mainly a much needed polar alignment on the system. As usual, PAM dribbled me a bit for an hour or so, but I eventually managed to get a plate solve from it (plate solve on Maxim was trivial for a long time) and a session of measure-adjust-refine occupied my time while D&K tried to adjust the GM-8 that apparently had taken a bump. After some tweaking I looked for a target to test for alignment, and ended up doing a little more than half and hour on asteroid 9 Metis. Looking at the first and last frames from the sequence showed some movement in RA, so I went back and spent more time trying to further improve polar alignment. At the end of the night I had and error of less than 6 arcmin in azimuth, and less then 4 in elevation. Not good, but the observatory is not ready yet, and the odds of someone giving it a bump while doing some maintenance work are not slim, so I shutdown the pier at 4 am and 20 minutes later I was inside the sleeping bag.

By 8h40m I was tired of being awake trying to rest (insomnia has been frequent lately) and went back to the observatory to check the equipment. Doctor and Kid left later in the night, and everything was parked and covered in dew, so I opened the roof and let the equipment dry for a bit. It was a sunny morning with blue sky, nothing like the cloudy and boring day before, and I sat on some stairs to think for a bit, while getting some sun.

Eventually the Kid got up, and together with the Engineer (that had arrived late the previous night) we went for a coffee and a bit of talking, before raising our sleeves and get some work done, mainly electric work related with the UPS system on the observatory, and some cable management to avoid a rats nest. All went smoothly without much notice, with the exception of some excess energy that “blessed” my hand, kindly provided by the friendly chinese that manufactured a power strip with the live blue wire connected to the earth contact… Too bad it didn’t light me up.

This time we packed early, had lunch by 2pm, returning home after it with a brief stop for another coffee. 

Another weekend, another Sunday…

Click on the image for full size

After a few tries, that were used mainly to refine procedures and test practices, finally, my first exoplanet light curve! The data was captured on the night from September 13 to 14, 2008, in the UFObservatory, Portugal, with a Celestron C8 and a Atik 314L (full details soon) guided by a Losmandy G11. It was a full moon, and the transparency wasn’t very good, but the night had the purpose to setup piers III and IV at the (still under construction) UFObservatory. Pier II (mine) was already setup, aligned, and ready to image, and this exoplanet was used to perform technical first light for the instruments.

Capture started at 2008/09/13 22h49m44s UT and the last frame is time-stamped 2008/09/14 2h26m31s UT, covering a little more than 3.5 hours. The ephemerides for this transit (from www.transitsearch.org) predicted beginning of transit at 2008/09/13 23h53 UT (JD 2454723.50) ending at 2008/09/14 1h35 UT (JD2454723.57). The scattering on the measurements is very high, much more than I expected, and will have to be further investigated, but for now I’m blaming it on improper calibration (I didn’t captured flat frames for the sequence) and poor guiding. RA guiding was very acceptable, but Gemini often displayed a “DEC motor lags” message. Both RA and DEC motors were examined but there’s was no sign of binding on the worms, so next session is going to be monitored with a voltmeter, to make sure the power supply is functioning properly.