8/7/2023 0 Comments Autumn sky map algolHe writes about astronomy for Natural History magazine, the Farmers' Almanac and other publications. Joe Rao serves as an instructor and guest lecturer at New York's Hayden Planetarium. Should you be blessed with clear skies, enjoy this "eye-catching" performance. Because the entire eclipse takes 9 hours and 40 minutes from start to finish, the entire performance can be seen in a single night when the timing is right, such as will be the case on Friday night from coast to coast. In 1782, amateur astronomer John Goodricke was the first to realize that this star was really a pair of stars orbiting a common center of gravity and that when the dimmer of the two crossed in front of the other, the light from Algol appeared to fade. Thus, its name seems to suggest that the medieval Arabs were aware of its marked changes in brightness. Some believe Algol is so called because it marked one of Medusa's eyes, which seemed to "wink" every 2.867 days. Later, when flying over the seacoast of Ethiopia with his winged sandals, he noticed the sea monster (Cetus) approaching the beautiful chained princess, Andromeda, and dispatched the monster. However, to avoid being turned to stone as he aimed his sword, he looked at the reflection of the sleeping Gorgon in his highly polished shield and beheaded her. Perseus' mission was to behead Medusa and bring the head back to the island of Seriphus as a wedding gift. Anyone who gazed at her immediately turned into stone. In the mythological figure of Perseus - the son of Zeus and the mortal Danaë - Algol marks the head of the Gorgon Medusa, a hideous creature with a form of naturally curly hair - snakes. Algol is at minimum light for about 20 minutes - as the large, dim star passes across the smaller, brighter one - then it gradually returns to normal.Īlgol brightens and fades almost like clockwork, but nonetheless, is still subject to small, complex changes which are of considerable interest to astronomers. If you are observing casually, a look every half hour is sufficient if you are trying to determine the time of mid-eclipse, 10-minute intervals are better. Two hours before the predicted minimum, start checking Algol's brightness. Farther west, Algol will be lower in the sky the Mountain and Pacific time zones will either still be in twilight or it will be right around sunset, so only the gradual increase in brightness (after it gets sufficiently dark) will be observable. This is about one hour after evening twilight ends for the Central time zone, and therefore observers should begin their watch as soon as the sky becomes dark. 27) with Algol situated about halfway up in the northeast sky. 26 will be best seen from the eastern and middle parts of the United States and Canada since its midpoint is due at 8:50 p.m. From most locations, Algol will appear to soar high above the eastern horizon. The former date is particularly suitable for much of the continent, maximum eclipse occurring just after midnight Eastern Daylight Time (11:02 p.m. 23, and again during the evening hours of Monday, Oct. Two eclipses this weekįor North American viewers, the two most favorable occasions this month for watching an Algol eclipse will come during the late-night hours of Friday, Oct. Most of this change occurs within the three hours before and three hours after the time of maximum eclipse. During this interval Algol fades gradually to minimum light, then gradually returns to full brightness. The light variations recognizable by the naked eye are confined to less than 10 hours of each cycle. It is also called Metallah (or Mothallah), meaning "head of the triangle." And, in fact, our word "ghoul" comes from the same Arabic word. Its name derives from Ra's al-Ghul, Arabic for "the demon's head," according to the late star-name expert George A. At minimum, it is slightly brighter than another nearby binary star system, Alpha Trianguli. (Image credit: SkySafari/Simulation Curriculum)Īt its maximum light, Algol is about equal in luster to the nearby star Gamma Andromedae, a triple-star system in the Andromeda constellation also known as Almach. At minimum, it is slightly brighter than Metallah. At its brightest, Algol is about as bright as Almach.
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |