Stars


One of my favorite things to do with students in the late fall is to take them outside and point first to the Orion nebula, then to the Pleiades, and finally to the Hyades cluster, saying “these are snap shots in the evolution of open clusters.” Each of these systems is the home of young stars, but while the Orion nebula is very much a stellar nursery, with stars just 10 million years old or younger, the Pleiades, is more...

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The word Novae generally refers to a “New Star,” or a “Guest Star” – An object that springs up in the sky quite suddenly as a new but non-permanent object. Today we give these non permanent sky features a dozen or more names: Supernovae (types I & II with all sorts of extra letters), Recurrent Novae, Cataclysmic Variables and more. While observed and documented for about 2000 years, only for the last...

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AAVSO/BAA Day 1: Binary Adventures


Posted By on Apr 11, 2008

Variable stars come in many forms – there are happy little regular stars, widely separated and merrily circling ones dancing an eon long dance. Some white dwarfs – dead stars, cooling into stellar embers of stars – become vampires as they gravitationally suck mass from their companion and heat themselves back out of the stellar grave. There are stars with touching atmospheres that are merging, spiraling, reheating in...

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After several days of travel, I’ve settled into the front row of the BAA/AAVSO meeting in New Hall, in Cambridge, UK. Dr. Paula Skody is giving an excellent talk on pro-am collaboration to make Hubble Space Telescope observations of cataclysmic variables. She studies pulsating white dwarfs – stars whose outer 99% have oscillations that can be seen as high speed, slight changes in brightness. The most interesting of these...

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I saw a really cool paper (to me) on the pre-print server today. Astronomers Kuzic et al. have made detailed measurements of two groups objects in the center of the galaxy within half a parsec of the center of the Milky Way. These objects, named IRS 13E and IRS 13N (aren’t those exciting names?) are each composed of very young stars (less then 1 million years). The objects in 13E are Wolf-Rayet and O-Type giant stars that will...

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Tau Boo Back Flips (magnetically)


Posted By on Feb 13, 2008

As some of you may know, my favorite favorite star to bring up when discussing binaries is Tau Boo B (Go ahead, say it out loud. Giggle. Join me in the giggling. Wasn’t that fun?). This little red dwarf star is the companion star to the much more famous, but no where near as fun to say, bigger Tau Boo A. Tau Boo A is a solar (sorta) twin, with similar temps (it’s a bit hotter) and a similar mass (its a bit bigger) to the...

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