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Monthly Archives: March 2011
Saturn’s rings surge in brightness this week
On Sunday Saturn reaches opposition, when it will be closest to the Earth for the year. The closer something is to us, the brighter it appears in the sky. Not only will the planet be brighter than compared to months … Continue reading
Tagged Astro Bob, backscattering, opposition, Saturn, Seeliger Effect
5 Comments
Life’s nice with liquid, gas and ice
Mud turned to ice under our feet last night as the temperature dropped to 20 F. I spoke before a group of naturalists at the Boulder Lake Environmental Learning Center north of Duluth. After the talk we walked outside and … Continue reading
Crescent moon by way of nova
Waking up to a crescent moon was nice enough this morning. I went out to spy a possible new nova in the summer constellation of Sagittarius. Novas occur in very close double star systems where stars like our sun or … Continue reading
Tagged Astro Bob, moon, nova, white dwarf
4 Comments
See the Spring Triangle and Saturn tonight
I’m not the first to call it the ‘Spring Triangle’ but the name sure fits. We’re talking about Arcturus, Saturn and Spica and what a fine figure they cut in the eastern sky from 10 o’clock onward. I suppose it … Continue reading
Tagged Astro Bob, methane, Saturn, Spring Triangle, Titan
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Curious glows of the night plus the sun gets cookin’
The sun is starting to heat up again. OK, it’s already hot, but do you remember the big sunspot group (1166) that jump-started the northern lights earlier this month with a succession of medium to large flares? After rotating around … Continue reading
Tagged Astro Bob, aurora, flares, gegenschein, sun, zodiacal light
4 Comments
Mercurial light warms up tonight’s Earth Hour
Wow, it’s been a busy day. So much so I nearly forgot about Earth Hour, an annual ‘turn off the electricity’ event celebrated around the world at 8:30 p.m. local time. It began in 2007 in Australia over concerns about … Continue reading
Tagged Astro Bob, Earth Hour, Mercury
1 Comment
Of frost and space station watching
Space station watchers are back in business again starting tomorrow morning with a 6:34 a.m. pass in the southern sky as seen from the Duluth region. This several-week-long ‘season’ of visibility features grazes of the moon and bright star Vega … Continue reading
Tagged Astro Bob, frost, ISS, space station
2 Comments
New aurora video a masterpiece
After more than six months of picture-taking on dozens of cold nights, photographer Ole Salomonsen of Tromsø, Norway has combined some 50,000 still images into a spectacular 4-minute video of the northern lights. Key among his goals was to show … Continue reading
Tagged Astro Bob, aurora, Ole Salomonsen, orrery
2 Comments
Astronomers discover star no hotter than your sauna
I boil water for tea twice a day. And while boiling water burns like heck if it spills on your hand, it’s not usually what we think of when it comes to star temperatures. Those typically range from the low … Continue reading
Tagged Astro Bob, brown dwarf, star
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A little tilt is all it takes
I hope the first couple days of spring have lived up to seasonal expectations where you live. They have here, but now a howling snowstorm is on its way, threatening to repave all the lovely, exposed ground with a foot … Continue reading