Over the years I have hand wired so many microcontroller PCB’s. Along with my own projects for myself there are more than a dozen of my little microcontroller devices at work about the observatory. The OSIRIS IR calibration source, the Keck 2 dome inclinometers, a precipitation sensor interface, the Keck 1 AO electronic vault temperature sensors, the weather mast fan and shelter controller, the list goes on. Anyplace a bit of electronic intelligence is needed for the task.
Of course the challenge is that each of these controllers has been hand wired and built for a specific task. This takes a few hours of running little wires on a perfboard. And while I enjoy such wiring, it does make the task take notably longer.
While a couple of my microcontroller designs have been laid out on proper circuit cards, like the SciMeasure camera exposure controllers, I have never laid out a general purpose microcontroller PCB. This is not for lack of thinking about it, so many times I have considered this could be so much easier if I could only invest a little time in a layout.
Today Mercury will be at maximum western elongation, as high in the morning sky as it will appear for this current apparition. After today the planet will slide back into the dawn, passing through superior conjunction on March 6th to reappear in the evening around the end of March.
The best evening apparition of 2017 will be in July, with a maximum elongation of over 27°. The best morning apparition will be May at over 25°, with today being nearly as good at over 24°.
There are no transits of Mercury in 2017, the next will be Nov 11, 2019.
61G lava flow this morning, first time I have been out since the shelf collapse, what a difference, it just pours out of the tube. There is a small fragment of the old shelf, it continues to collapse, heard and watched a couple truck sized chunks fall out of it and into the surf.
Did another dawn attack, arriving at the flow about 2am, staying until after sunrise. The new rope line is stupidly far back, so far back no one was honoring it. I stayed about 200-300 yards away, but saw folks on the top of the cliff over the tube where I had seen glowing globs land just half an hour before.
This February will feature a very close approach of Comet 45P/Honda–Mrkos–Pajdušáková. The comet will pass about 0.08AU (11.9 million km or 7.4 million miles) from Earth on February 11th, making it an easy telescopic object, and a marginal naked eye comet at around 6th magnitude.
This is a short period comet with an orbit only 5.25 years long. At aphelion it orbits out very close to Jupiter, while at perihelion it is well inside the orbit of Venus. As such it may occasionally pass very close to Earth.
The comet itself is rather interesting. Discovered in 1948 the comet has been a the frequent target of scientific observation as it may pass quite close to Earth. In 2011 it passed about 0.06AU from Earth and was the target of radar observations.
Currently in the evening sky the comet is sinking into the sunset rather rapidly. It will pass by the Sun around the end of January to appear in the morning sky. It will rise rapidly above the dawn, by February 5th it will be rising at 3:22am, about four hours before the Sun. On the day of close approach, February 11th, the comet will rise well before midnight in the northern sky.
The comet is predicted to remain quite bright, around 7th magnitude or better for all of January and most of February, possibly peaking at around 6th magnitude near close approach to the Earth. As this is a well observed comet these magnitudes are likely to be reasonably accurate.
Of course any comet getting this close to us will catch the attention of the doomsday preachers and assorted apocalyptic predictions. Comet 45P is already a bit of a YouTube celebrity with quite a few videos filled with dire predictions.
I predict that we will have a pretty comet in the new year’s sky to provide a nice target for telescopic observations and astrophotographers. I would suggest making a point to get out and observe this comet as it passes by.
A perfect blue day at Māhukona, in a word… Idyllic.