by Kim Malville

Almanac

Jupiter continues to dominate the evening skies. It is in the constellation of Taurus close to Aldebaran, the red eye of the Bull. A large trapezoid is formed by Jupiter, Aldebaran, Betelguese and Capella.

March 1-2: Saturn rises about 11pm close to the waning moon, and they travel together throughout the night. Saturn lies between Virgo and Libra and is retrograding.

March 7-10: Comet PanSTARRS may become visible to the naked eye. Look low in the west just after sunset.

March 10: Daylight savings time starts at 2am.

March 12-18: This should be the best time to view Comet PanSTAARS.

March 20: Vernal equinox, when the sun moves into the northern hemisphere of the heavens: 5:02am.

March 28, 29: The moon, slightly past full, is close to Saturn.

Comet PanSTARRS

“Comets are like cats. They have tails and they do precisely what they want.” David Levy

This may be the best comet in our skies in years at our latitude. Its funny name comes from the telescope that discovered it: the Panoramic Survey Telescope And Rapid Response System of the University of Hawaii. This new telescope is designed to detect asteroids and comets that come near and possibly threaten the earth. Ironically it missed the asteroid that exploded over Russian on Feb 14. The telescope was first put into operation in May 2010 and since then has detected more than 4000 previously known asteroids and 7 completely new ones. It has also discovered 9 supernovae and, of course, one comet. This new comet is falling toward the sun out of the Oort Comet Cloud, where it has been hiding from view for 4.5 billion years. Never before has it felt the heat of the sun, and there’s no telling how it will behave. These new comets have coatings of volatile substances, which may evaporate quickly, cause a rapid increase in brightness, and then fade.  It will come closest to the sun on March 10, passing within 28 million miles of the sun, well inside the orbit of Mercury. By then it should  have grown a long tail. Predictions of its brightness after March 12 have varied from Venus to the stars of the Big Dipper, but it will make March a very special month.

Russia’s tiny asteroid

The object that exploded over Russia last month was a tiny asteroid that measured roughly 45 feet across, weighed about 10,000 tons, and traveled about 40,000 mph. The object vaporized 15 miles above the surface of the Earth, causing a shock wave that triggered the global network of listening devices that was established to detect nuclear test explosions. The force of the explosion was between 300 and 500 kilotons, some 30 times larger than the Hiroshima explosion. Some 1500 residents of Chelyabinsk were injured, mostly due to flying glass. Damages are estimated at $33 million due to the sonic shock striking the city and causing walls to collapse.

The fact that the asteroid hit on the same day that we were expecting the close passage of a larger asteroid is an extraordinary coincidence. The smaller asteroid was traveling in a very different trajectory and much more quickly, indicating that the two were not at all related. This is the largest recorded meteorite/asteroid explosion since the Tunguska explosion in 1908, which leveled more than 800 square miles of forest in Russia. This asteroid was too small and too dark for it to be detected by PanSTAARS.

 Hexagon on Saturn

It’s good to have mysteries. The clouds of the north pole of Saturn contain a very strange and unexplained hexagon. Nobody is sure why. Originally discovered during the Voyager flybys in 1980s, nothing like this has been seen anywhere else in the Solar System. It has lasted more than 20 years. Each of the six well defined sides are of nearly equal length. Four Earths would fit into each side. Beyond the planet in the photo, one can see the shadow of Saturn projected on its rings.

 Shadows on Jupiter

Two dark shadows move across the banded and mottled cloud tops of Jupiter in this amazing photograph taken on  January 3, 2013. Of the four bright Galilean moons (visible in binoculars) Io is the smallest and closest to Jupiter, while Ganymede is the largest. Io is the most volcanically active object in the solar system. Its orange color is due to the sulfuric magma that has coated its surface. Were any folks living in the cloud tops of Jupiter, they would experience a total solar eclipse when the shadow passes over them. The great red spot is on the right hand side of Jupiter in this picture.

Dung beetles and the Milky Way

A male dung beetle tries to impress his favorite lady beetle by rolling the biggest ball of excrement it can create along a straight line. Rival males are known to overtake their rivals and claim the affection of the waiting lady. Speed and straightness are vital.  It has recently been demonstrated by zoologist Eric Warrant at Lund University in Sweden that these beetles, who work at night, follow the light of stars and the moon. Their eyes are good, about 1000 times better than honey bees. Birds, seals, and, yes, even humans use the stars to navigate, but this is the first time it’s been shown that insects can follow starlight. It turns out they are following the bright line of stars in the sky that is our the Milky Way. In an experiment in a planetarium when only the Milky Way was projected on the dome, the beetles followed a straight line across the floor. When the planetarium projector was turned off, they rolled their dung in circles. Because the Milky Way is brighter in the southern hemisphere, life is good for dung beetles south of the equator.