Forty years ago I received my first, and until about 10 years ago my only, telescope: a classic 60mm refractor on a German Equatorial Mount. What it lacked in aperture it more than made up for in the quality of the images. Over the years I have seen shadow transits on Jupiter, Syrtis Major and polar caps on Mars, and, from a very dark sky, M81 and M82 through that scope. But perhaps the most incredible thing that scope showed me was the wonderfully different colored stars all over the sky. Its pinpoint images spawned a love for double stars that showcase contrasting colors, and provided a welcomed relief from the marathon of faint fuzzies to which my friends with more massive telescopes insisted on hopping.
Hence the topic of the club’s first Bright(er) Night Observing: Red and Double Stars. We’ll be tracking down a select number of the stars in the observing list that can be found by clicking on the “Event” link to the left of the blog, and following the
“Starlist.pdf” link.
In particular, we will be aiming for UU Aurigae; W and h 3945 in Canis Major; ι and X Cancri; γ Eridani; δ Geminorum; β, ε and ζ Monocerotis; W, δ, ζ and σ Orionis; η Persei; and 30, TU, ΟΣΣ 66 and φ Tauri. All these targets, and more, can be found on the starlist pdf.
Some of the double stars on this list are optical illusions, chance alignments of totally unrelated stars. Others, such as σ Ori are wonderfully complex systems of gravitationally-bound siblings. Some are quite close together and sometimes difficult to separate, others are fine objects for binoculars. I have tried, in this list, to focus on double stars whose components exhibit significant color differences, differences that are not simply appealing to the eye, but which also tell astronomers significant detail about the stars themselves.
I have also included some particular, and peculiar, red-colored stars called carbon stars – some are stand-alone stars, others are members of a double-star system. What’s not to like about carbon stars (originally classified as spectral class R or N and now reclassified as C): they appear deeply and vividly red in most scopes, particularly those with long focal lengths, and are persistent reminders of stars’ role in the creation of every element heavier than hydrogen and helium. This process, called nucleogenesis, occurs either within a star during its normal lifespan, or in the supernova explosion that marks the death of more massive stars. Carbon stars receive their name, and deep red color, from the fact that they have reached a stage in their life-cycles when they have been burning helium instead of hydrogen for fuel and have thus produced significant amounts of carbon and whose outer atmospheres contain more carbon than oxygen, giving the star a sooty atmosphere which scatters back the higher wave-length light leaving the star appearing red.
I hope you can join us on the 22nd!
Steve
The Jan. 29 & 30 Full Moon will be the "largest" Full Moon of 2010, because the Moon is Full at 1:18 am, Sat., Jan. 30, and at Perigee (closest to Earth) about 2.7 hours later. The Moon's Orbit, like virtually all Orbits, is an Elipse. Moon will be closest to Earth since Dec.12, 2008. Astronomical Tides will be unusually high. The Full Moon in January is often called the "Wolf Moon". Most cultures named the Full Moons. We get our Full Moon names from Europeans, Native Americans, and primarily - Colonial Americans. There were more wolfs in Colonial America and their howling was more noticed in January.
