The W. M. Keck Observatory has successfully completed a $4 million campaign that will give astronomers the most detailed Adaptive Optics images of the cosmos ever created by mankind. Furthermore, the campaign was funded entirely by private philanthropy.
Today Comet C/2011 L4 (Pan-STARRS) will make its closest approach to Earth. Not that that is saying too much, close approach will be 1.09 AU or about 101,300,000 miles, just over the average distance from the Earth to the Sun. In contrast Comet C/2012 S1 (ISON) will approach us to closer than half that distance, about 0.42 AU or 39,000,000 miles from Earth on December 26th, 2013.
The comet should be visible as a 2nd magnitude object 7° above the horizon and a little south of the Sun at sunset. It will climb higher each evening, passing through perihelion, close approach to the Sun on March 10th.
C/2011 L4 ( PanSTARRS ) positions in the sunset as it passes through perihelion, chart for March 10th, 2013
With data collected from the W. M. Keck Observatory, California Institute of Technology (Caltech) astronomer Mike Brown — known as the Pluto killer for discovering a Kuiper-belt object that led to the demotion of Pluto from planetary status — and Kevin Hand from the Jet Propulsion Laboratory (JPL) have found the strongest evidence yet that salty water from the vast liquid ocean beneath Europa’s frozen exterior actually makes its way to the surface.
The data suggests there is a chemical exchange between the ocean and surface, making the ocean a richer chemical environment, and implies that learning more about the ocean could be as simple as analyzing the moon’s surface. The work is described in a paper that has been accepted for publication in the Astronomical Journal.
The findings were derived from spectroscopy delivered from the Keck Observatory, which operates the largest and most scientifically productive telescopes on Earth.
“We now have the best spectrum of this thing in the world,” Brown says. “Nobody knew there was this little dip in the spectrum because no one had the resolution to zoom in on it before.”
Today the planet Mercury passes through inferior conjunction, passing between the Sun and the Earth. In a week or so the planet will again be visible in the dawn sky, climbing higher each day. Maximum elongation will occur March 31st.
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.
C/2011 L4 (PanSTARRS) positions in the sunset as it passes through perihelion, chart for march 10thFor 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.
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.
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.
A two mirror laser spirograph buildI 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!
Schematic for the SpiroLaser control PCBTime 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.
