Thursday, January 9, 2014

The Ellensburg sky for the week of 1/11/14

Saturday: One Family Affair explored the trials of well-to-do civil engineer and bachelor Bill Davis as he attempted to raise his brother's orphaned children in his luxury New York City apartment (as described on Wikipedia). Another family affair explores how a well-to-do Solar System raises its constituents from birth, through growth, change, and death. Just like Buffy and Jody started off full of energy, planets start out hot and molten. Cissy got wrinkles as she approached middle age; planets become cratered as they age. We watched the TV show “Family Affair” to learn about a nontraditional Manhattan family grew and changed. Astronomers study other planets to learn how the Solar System will evolve. For more information about this Solar System Family Affair, go to http://goo.gl/G029D. Jupiter, the dad of the Solar System family, is about three fists held upright and at arm’s length above due east at 7 p.m.

Sunday: How do you study the life cycle of a dog? Easy. Get a dog from the animal shelter, care for it for 15 years and study it. How do you study the life cycle of a star? Easy. Pick a star, watch it for a few billion years, and…. Wait a minute. Astronomers can’t observe something for a few billion years. Instead, they study stars that are at different points in their long life cycle and piece together the information from those different stars. What they do is like studying a one-year-old dog for a few minutes, then studying a different two-year-old dog for a few minutes, and so on. The sky in and near the constellation Orion provides an example of four objects at different points of star life.
First, find Rigel, the bright star in the lower right corner of the constellation Orion. This star, rapidly burning its fuel for a high energy but short-lived existence, is three and a half fists above the south horizon at 10 p.m. About one fist up and to the left are the three objects of Orion’s sword holder. The middle “star” is really a star-forming region called the Orion nebula. There you’ll find baby Suns. Now, look about two fists to the right and a little below Rigel. You should be looking at a star that is about one tenth as bright as Rigel but still the brightest in its local region. The third star to the right of that star is Epsilon Eridani, the most Sun-like close and bright star. Betelgeuse, in the upper left corner of Orion, is a star at the end of its life that started out life a bit larger than the Sun.

Monday: Mars is about four fists above the south horizon and Saturn is about two fists above the east-southeast horizon at 6 a.m.

Tuesday: Jupiter is a half a fist to the upper left of the moon in the eastern sky at 7 p.m.

Wednesday: It’s a bird. No, it’s a plane. No, it’s a super moon. During this full moon, the moon is at perigee, meaning it is at its closest to the earth. And when items are closer to us, they appear larger. So a super moon is really a close moon, a moon that leads to extra high tides and brighter night skies.

Thursday: January is the coldest month of the year so it is time to turn up the furnace. Fornax the furnace is one fist above due south at 7 p.m.

Friday: What you see with the naked eye isn’t all that can be seen. While astronomers can learn a lot from observing the sky in the visible wavelengths, many celestial objects radiate more light, and more information, in wavelengths such as radio, microwave, infrared, ultraviolet, x-ray, and gamma ray. In 2009, NASA launched the Wide-field Infrared Survey Explorer (WISE) to study objects that radiate in the infrared range such as asteroids, cool dim stars, and luminous galaxies. For an interesting comparison of how different wavelengths show different aspects of a galaxy, go to http://goo.gl/nvuax. If it weren’t for infrared telescopes such as WISE, astronomers would not know about the significant amount of dust in galaxies.


The positional information in this column about stars and planets is typically accurate for the entire week. For up to date information about the night sky, go to https://nightsky.jpl.nasa.gov/planner.cfm.

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