Category: Astronomy

Exploring the cosmos

Comet C/2011 L4 Pan-STARRS

Like so many other amateur astronomers, I am eagerly awaiting the appearance of Comet C/2011 L4 Pan-STARRS.

The comet was discovered in June of 2011, by the Pan-STARRS survey telescope atop Haleakala, Maui. The comet will pass closest to earth on March 5th, at a distance of 1.09 au. Perihelion, the comet’s closest approach to the Sun, occurs early on March 10th UT.

Comet 2011 L4 Perihelion
C/2011 L4 (PanSTARRS) positions in the sunset as it passes through perihelion, chart for march 10th
For northern hemisphere observers the comet is still quite low, just rising out of the Sun’s glare. Over the next week it will rise above the sunset, and will be 12° above the horizon at sunset on Saturday, March 9th.

Initial predictions were quite optimistic with this comet, indicating a possible -1 magnitude for the comet. Reality seems to be somewhat more restrained, with a peak somewhere between magnitude one and two being more likely. Reports indicate that the comet has brightened to about 2nd magnitude, bright enough to be easily seen without optical aid.

Even more convenient, the comet will be well placed for observation this coming weekend. With new moon occurring on March 11th, this will be the prime weekend for a telescope outing. Amateur astronomers everywhere are already planing for this weekend. Our local club is no exception, expect a good crowd of telescopes to be at the Mauna Kea VIS this weekend. Myself? I will probably setup at the Substation site, just across the road from the VIS. The site offers a much better western horizon, which is blocked from the VIS by a line of pu’u, old cinder cones.

I will be taking photo gear, looking to get a decent photo of the comet. Stay tuned to Darker View to see the results if I meet with any success.

The latest orbital elements from the MPC

Another interesting opportunity will come on March 12th, when a slim crescent Moon will join the comet in the sky. A 1.4 day old moon, about 2% illuminated will be about 4° north (to the right) of the comet.

Laser Spirograph

With an upcoming open house, everyone around the observatory is frantically trying to get everything in place. There will be all manner of science exhibits throughout the observatory headquarters complex. Exhibits about our research, controlling the telescopes, an IR camera display (Get your portrait in IR!), liquid nitrogen ice-cream, just a lot of fun.

Laser Spirograph
A two mirror laser spirograph build
I am coordinating an exhibit we named Optics Lab… As you would expect, most of the exhibits in our area teach basic optics, light, lenses, etc. Understanding light and optics is a basic skill in a large observatory. We will have a few lenses on rails, a laser ray-trace table with acrylic lenses, an exhibit on polarization, and even a simple laser interferometer.

When attempting to teach something, a little eye-candy is helpful to catch the attention of the audience, particularly kids. Our group includes a laser engineer and a laser tech, so the use of lasers was obvious. There is little that catches the eyes of a kid faster than a bright laser beam. One of the first ideas they tossed on the table was a laser spirograph. After a few moments thought the answer was clear… I can build that!

SpiroLaser PCB
Schematic for the SpiroLaser control PCB
Time to dig about in the scrap box! Actually more than a few boxes in my case, I am a bit of an electronics pack rat. A green laser module… Check! Small DC motors… Check! A few voltage regulators… Check! A couple potentiometers… Check! First surface mirrors… Check! In an hour of rummaging about I quickly located everything that was needed.

Continue reading “Laser Spirograph”

The Forecast was Correct

It does appear that we got a substantial amount of snow last night. Webcam images show quite a bit of snow. No tracks either, no one has attempted the summit yet, the snowplows have not made it up.

I am not scheduled to go up today, or even again this week. Fresh snow can be pretty, shoveling snow? Not so much. Actually, I expect that the summit crew will be sitting at Hale Pohaku much of the morning, waiting for the plows to complete their job, not the most productive way to spend the day.

The snow is expected to last through today and into tomorrow. The White Mountain should be white for a while.

Fresh Snow
Fresh snow atop Mauna Kea, the first good storm of 2013

A Little Snow in the Forecast

It was a gorgeous day when we arrived on the summit. A deep blue sky above brilliant white snow covering the slopes. It was difficult to put much faith in a forecast calling for truly dire weather. I could see nothing to the southwest, the direction this weather was approaching from, just the blue Pacific stretching to the horizon.

Snow
A little fresh snow on the summit of Mauna Kea
Oh yeah… The car is still there. It is a truly sad sight to see, the car halfway down the slope. Rumor had it that a tow truck was to come up today to remove the vehicle, but the car was still on the slope when we left.

Not a bad day, I accomplished everything on my to-do list for the day. Some work in AO to check for any stray light, removing some old servers to make way for a new system, locating and labeling some optical fibers that are already in place for this same system. Everything went well, except the lunch time cribbage game, I lost badly.

The weather was degrading all day, first the clouds loomed overhead, then they descended as a heavy fog while the temperature dropped. It did indeed begin to look like the forecasts might have a bit of truth. The prediction is for heavy snow, as much as 6-10 inches. Not sure if that will materialize, it would be nice, we have not had any real snowfall this winter. I will just have to check the webcams tomorrow morning.

It was beginning to snow when we pulled out.