by Kim Malville
The skies of March and April gave us spectacular views of Venus in the evening. At the start of May Venus will continue to stun us by reaching an altitude of 35° above the western horizon and remaining visible for three and a half hours after sunset. In the beginning of the month you will find Venus close to the tip of the northernmost horn of Taurus the Bull, the star known as El Nath, “the Butting One”. The other horn known as Tien Kuan, “the Gate of Heaven” is next to the Crab Nebula, the remnants of the famous supernova of 1054.
But this is the month for the demise of Venus as it plunges toward the horizon, moving to only 3° above the horizon at the end of the month. It will vanish entirely, lost in the light of the sun by June 3, when it is in conjunction with the sun.
May 5: If you have never seen Halley’s Comet, you should catch this meteor shower, the Eta Aquariids. These meteors are fast and bright, streaming out of the constellation of Aquarius, often leaving bright tails of hot flowing gas. Although the nearly full moon will be bright, this year the shower is predicted to be stronger than usual. The best time will be between 3:30 and 5am. What you will see will be fragments of Halley’s Comet, which were dropped in its orbit. As these sand-grain sized fragments burn up in the atmosphere, they deposit atoms and molecules left over from the birth of the solar system. My advice, enjoy these meteors. Don’t wait for the next appearance of Halley’s Comet, which is due on July 28, 2061.
May 7: Full moon. Known variously as the Full Flower Moon, the Corn Planting Moon, and the Milk Moon. The latter name comes from all the delicious flowers goats and cows eat during spring, thereby producing equally delicious milk.
May 11: Mercury appears in our skies in west-northwest below Venus.
May 15: Venus has turned into a lovely moon-like crescent in which 11% of the disk is illuminated. Some people with excellent eyesight can detect the crescent without a telescope. One technique is to look at Venus using a pinhole camera, with a piece of cardboard with a hole one or two mm. Finally, you could try holding binoculars very steady to view the crescent of Venus. It was Galileo’s observations of Venus that shot down the belief that Earth was in the center of the universe. Using his telescope, Galileo found that Venus went through phases like our Moon. Galileo’s observations of the phases of Venus was another nail in the coffin of the geocentric cosmos. To the misfortune of Galileo, his discovery of the phases of Venus angered the leaders of the Church of Rome, leading to the appearance of Galileo before the Inquisition.
May 21/22: Venus and Mercury move into conjunction, visible low in the west-northwest horizon.
May 23: The very slender crescent moon appears close to Venus and Mercury near the horizon.
Black holes are messy eaters
Black holes are terrible gluttons, eating everything that comes their way. Like Henry the Eighth, they gnaw on vast haunches of matter and energy and then toss the partially consumed bones out into space. In 1974 Stephen Hawking shocked the world of physics and astronomy by showing that black holes can leak energy and eventually disappear. His revolutionary idea was that some of the immense gravitational energy outside the edge of a black hole can be converted into matter in the form of pairs of particles, an electron and a positron (negative electron). Instead of eating both of them, one member of that pair gets sucked into the maw of the black hole while the other escapes. If a positron escapes, it quickly becomes annihilated in a burst of energy when it meets an electron, producing Hawking Radiation. This “partly consumed food” pulls energy and matter away from a small black hole, leading to the black hole’s death.
A similar process has just been discovered involving two stars orbiting each other. Such a pair of stars wandered too close to the black hole in the center of our galaxy. One member of this pair was eaten by the black hole and the other was tossed away at a great speed. That star was recently discovered rushing away from the black hole in the center of our galaxy at a high speed of 4,000,000 million miles an hour. Our galaxy is a large place, and it will take that star 100 million years to leave the Milky Way entirely. Most stars in our galaxy have planets and if there is one similar to the earth with inhabitants who have eyes to see the skies, what a wild ride they are having!
Black hole burps
You may remember the amazing photograph of a black hole that appeared last year, produced by a collaboration of 200 astronomers using a combination of eight telescopes on four continents. That black hole in the center of M 87, lying at a distance of 55 million light years, is burping hot clouds of matter traveling 99% the speed of light. As matter fell inward toward the event horizon of the spinning black hole, it was caught up in tangled magnetic fields. Those magnetic fields became coiled up like a corkscrew and sprung outward, accelerating the fastest moving particles in the universe, which reach us as cosmic rays. (Note: past tense is appropriate because what we observe occurred 55 million years ago). Light from those blobs of hot gas were just recently observed by the Hubble Space Telescope. Thank your lucky stars that we don’t live in that galaxy.