Astro Bob blog: Celebrate Earth Hour tonight; amateur discovers a new cometEnjoy a darker night sky at least for an hour tonight plus an amateur astronomer discovers a new comet.
By: Bob King, Duluth News Tribune
Celebrate Earth Hour tonight
The gibbous moon glides toward Saturn over the next two nights while leaving Leo's brighest star Regulus behind. The map shows the sky around 9:30-10 p.m. Created with Stellarium
What better way to celebrate Earth Hour than by turning off the yard lights and stepping outside into the moonlight. People worldwide will celebrate the hour between 8:30 and 9:30 p.m. local time tonight by turning off unneccesary lighting and reducing electricity use in an effort to be more mindful of energy consumption and its potential effect on global warming. Global warming or not, I'll vote for just turning down the lights for no other reason than raising awareness of the precious resource above our heads. Dark skies have left our large cities and are rapidly dwindling all across the country.
It doesn't have to go this way. The small town of Spooner, Wisconsin, located an hour and a half south of Duluth, recently approved a new outdoor lighting ordinance that will reduce the amount of stray, wasted light from both commercial and residential lighting fixtures. Dennis Quinn, the city's building inspector and the person credited with creating the new ordinance, said the city has long been looking to reduce its glow and energy costs associated with unshielded lighting. Going forward, all new lighting fixtures in the city will have to be "semi-cutoff" that allow only two percent of the light to shine upwards. The rest remains on the ground where it's needed most. Greg Furtman, an amateur astronomer who lives near Spooner, made a presentation to the Planning Commission on energy-efficient lighting several years back, helping to push the idea forward. If Spooner can reduce its light pollution, any city can.
This patch of sky in the constellation Taurus was photographed at two different times by the Spitzer Space Telescope in the light of infrared or heat energy. The two frames are exactly aligned; the objects are moving because they're asteroids. There are lots of them -- how many can you see? Credit: NASA
NASA's newest space telescope, the Wide Field Infrared Survey Explorer (WISE), has been busy finding new asteroids at the rate of dozens per day. Most of these are out in the asteroid belt between Mars and Jupiter, but a few ramble along orbits that take them near Earth with the potential for hazardous encounters in the future. One of the discoveries will cross our planet's orbit just 700,000 miles away.
WISE photographs the sky in infrared, a form of light we sense as heat. Small, dark asteroids easily escape detection by ground-based telescopes in visible light, but WISE picks up their heat signature as they're warmed in sunlight. I think of the rock walls that line our area's creeks and rivers. Even on a winter day, you can feel the warmth they radiate with your hands after the sun's been out. Between the start of its mission in January until it ends this October WISE is expected to discover over 100,000 new asteroids in the main asteroid belt and hundreds of near-Earth ones.
A WISE infrared image of a cosmic rosebud blossoming with new stars in the cluster Berkeley 59 in Cepheus. The blue dots to the right of center are new stars which formed from the cloud's gas and dust. The red glow surrounding the hot, young stars is warm dust heated by the stars. The green material glows with heated polycyclic aromatic hydrocarbons, molecules that can be found on Earth in barbecue pits, exhaust pipes and other places where combustion has occurred. Credit: NASA/JPL-Caltech/UCLA
The mission will also shed light on other "dark" subjects including dim brown dwarf stars and vast clouds of cosmic dust including the one above that envelops a small star cluster.
An amazing thing happened this past Tuesday -- an amateur astronomer discovered a new comet using just a telescope and his eye. We live in an era of robotic patrols of the night sky; most comets are discovered by automated surveys long before ordinary humans find them. The discover, Don Machholz of California, is no stranger to visual comet hunting having discovered eight others between 1978 and 2004. Once again Mr. Machholz has beaten the machine to the punch.
He picked this one up with his 18.5-inch reflecting telescope on Tuesday but because of the approaching dawn couldn't tell which way it was moving. After what must have been a difficult three day wait, he confirmed it's new position on Friday morning and sent the news to the Central Bureau for Astronomical Telegrams, a clearing house for astronomical discoveries. This little fuzzy blob now has a name: Comet C/2010 F4 Machholz. It's rather faint -- 10.7 magnitude -- and located low in the northeastern sky in Pegasus just before dawn. We'll be watching and reporting on Don's new comet as more information arrives.