Bakersfield Night Sky – August 19, 2017
By Nick Strobel
Just two days until the start of the fall semester at Bakersfield College. Oh yes, and the great American solar eclipse too! We in Bakersfield will see a partial eclipse with at most 67% of the sun covered up. That 67% figure means 67% of the sun’s AREA will be blocked which means 67% of the sun’s light will be blocked. Another figure used to describe the coverage of the sun is the “magnitude”. The magnitude is the fraction of the sun’s DIAMETER that is eclipsed. For Bakersfield, the magnitude at maximum eclipse will be 0.734.
While the magnitude might be an interesting number, the 67% obscuration figure is the more important number because it tells you how much of the sun’s light will be blocked (see the inset of the star chart). Another important number to know is 10:20 a.m. That is when maximum coverage will be for Bakersfield viewers. That is mid-eclipse. The moon begins covering the sun at 9:04 a.m. and finishes covering the sun at 11:43 a.m. To find out the particular times and obscuration and magnitude amounts for your place of interest, go to https://eclipse2017.nasa.gov/sites/default/files/interactive_map/index.html .
With that map, you can zoom in to your particular spot and then click on your location to find the exact stats for that spot. The one tricky thing about the map is that it gives the times in “UT” which means “Universal Time”, the time along the prime meridian of zero degrees longitude. For the Pacific Timezone, subtract seven hours from the UT times to get our local time during daylight savings. Those in Idaho and Wyoming will need to subtract six hours from the UT times; those in Illinois will need to subtract five hours; and those in South Carolina will need to subtract four hours.
Last Saturday, the Kern Astronomical Society was out in force at the Beale Memorial Library to show the different ways of viewing the sun safely. There were telescopes with solar filters across the front of the telescope, a Coronado H-alpha solar telescope, an arc welders glass shade #14 mounted in a wood frame, and my SolarScope that projects an image of the sun onto a white board. KAS members also gave a couple of talks inside the library about the eclipse and viewing the sun safely.
If you couldn’t make it to that solar viewing party or need a refresher on how to safely view the sun, see the “Observe the Sun Safely” link on the William M Thomas Planetarium’s website at bakersfieldcollege.edu/planetarium . Also on the Planetarium’s website is a link to the live video stream on NASA TV happening during the eclipse. There will be images from eleven spacecraft, three NASA aircraft, more than 50 high-altitude balloons (in a project I described in my previous column), and the astronauts aboard the International Space Station.
Can’t make Monday’s total solar eclipse? The next total solar eclipse is on July 2, 2019 but you have to travel to the south Pacific or Chile or Argentina. The next total solar eclipse visible in the United States will be on April 8, 2024 . That one will sweep through Mexico, the eastern half of the United States, and the far eastern end of Canada. The next total solar eclipse visible in California will be August 12, 2045. Redding and Red Bluff will be on either side of the center line for that one, so the hotels and campgrounds will be packed on that day (remember that you read it here first).
Tonight the Summer Triangle will be high up in the evening sky. The Summer Triangle is made of the brightest stars in three constellations, Cygnus, Lyra, and Aquila. Deneb is at the tail of Cygnus. Cygnus looks like a cross flying down the length of the faint glow the Milky Way. Vega is at the side of Lyra. Four faint stars making a small slanted rectangle next to Vega make up the strings of Lyra. Altair is in the middle of the neck of the eagle Aquila. Two fainter stars are on either side of Altair to make an easy-to-see line.
Jupiter blazes away among the stars of Virgo in the southwest in the evening. A waxing crescent moon will form a triangle with Jupiter and the bright star to the left of Jupiter, Spica on August 25. The bright point we see as Spica is actually two very hot stars orbiting very closely to each other. One star puts out 12,100 times as much energy as the sun and the other 1500 times as much. The light from the binary has been traveling 250 years to reach us now. Have the two stars died and is their last light still traveling the vast distance to us? Most likely no. The Spica stars have lifetimes measured in millions of years. Though the brighter one is nearing the end of its stable lifetime, it appears to still have tens of thousands of years to go.
On August 29, the first quarter moon will be to the right of Saturn. The following night, the moon will be to the left of Saturn. There are now less than four weeks left for the Cassini mission orbiting Saturn!
The Fall 2017 schedule of public evening shows at the William M Thomas Planetarium is now posted. First show is Dawn of the Space Age on September 21.
Director of the William M Thomas Planetarium at Bakersfield College
Author of the award-winning website www.astronomynotes.com