Tuesday, July 10, 2018
The Ellensburg sky for the week of 7/14/18
Saturday: The Moon starts its night sky Solar System tour tonight. It is less than a half a fist held upright and at arm's length above Mercury, low in the west-northwest sky at 9:30 p.m.
Sunday: Fresh off of a successful appearance with the innermost planet, the Moon passes over Venus in the sky tonight. You'll barely be able to fit a finger between Venus and the Moon at 9:30 p.m., low in the western sky.
Monday: At 11:45 p.m., Saturn is almost exactly two fists above due south and Mars is one fist above the south-southeast horizon.
Tuesday: Say "Cheese". 167 years ago today, Vega, in the constellation Lyra the lyre, became the first star ever photographed. The photograph was taken at the Harvard Observatory using the daguerreotype process. Vega is the third brightest nighttime star we can see in Ellensburg, behind Sirius and Arcturus. Vega is nearly straight overhead at 11:00 tonight.
Wednesday: 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 2012, 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 celestial objects, go to http://goo.gl/nvuax. For example, if it weren’t for infrared telescopes such as WISE, astronomers would not know about the significant amount of dust in galaxies.
Thursday: Last week marked the three-year anniversary of NASA’s New Horizons probe passing by Pluto. If the band Nirvana was still together, they’d probably rewrite one of their hit songs to be called Heart-Shaped Spot, after one of Pluto’s most distinctive features. “She eyes me like a dwarf planet when I am weak. I’ve been imaging your heart-shaped spot for weeks.” Astronomers think this heart-shaped spot is a large plain of nitrogen ice that consists of convective cells 10-30 miles across. Solid nitrogen is warmed in the interior of Pluto, becomes buoyant, and bubbles up to the surface like a lava lamp. You will find great pictures and information about what New Horizons found this past year at http://pluto.jhuapl.edu/. Hey, wait, I’ve got a new complaint. People should be more interested in astronomy.
Friday: Take a two and a half hour walk. Too long, you say? Forty-nine years ago today, Neil Armstrong and Buzz Aldrin took the first ever walk by humans on another world. They spend two and a half hours setting up scientific instruments and collecting rocks for study back on Earth. Michael Collins orbited the Moon in the spacecraft the astronauts would use to return to Earth. The Moon is celebrating this event with Jupiter tonight. They are about two fists above the southwest horizon at 10 p.m. with Jupiter being less than a half a fist below the Moon.
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.