"STARGAZING"
Article by: Wayne Harris-Wyrick
July, 2008
Look at your star chart or the enlarged map below. Due south lies Scorpius, the scorpion, one of the oldest constellations in the sky. It sits on the ecliptic, the celestial pathway of the sun over the course of a year.
These ecliptic constellations, sometimes called the Zodiac, are used by astrologers (not astronomers!) to determine your horoscope sign. Your sign is the constellation the sun is in the moment of your birth.
The Scorpion, according to Greek mythology, was sent by Apollo to attack the mighty hunter Orion. Apollo was jealous of the attention that Artemis showed to Orion. In a great battle, the Scorpion killed Orion, but Apollo felt shamed for his actions and helped Artemis hang Orion's body prominently in the night sky.
The Scorpion was also placed in the sky, opposite Orion. As Scorpius rises in the east, Orion sets in the west. This arrangement prevented a continuation of the battle among the stars.
For Chinese skywatchers, the stars of Scorpius were part of a larger pattern called the Azure Dragon of the East. It represents spring and includes parts of the constellations Western skywatchers call Sagittarius, Libra and virgo. The Azure Dragon is the heavenly home of the Blue Emperor.
According to Polynesian mythology, the curving shape of this pattern of stars represesnts the jawbone that Maui used to hook the bottom of the ocean. he threw the great hook into the ocean and snagged the bottom, while his brothers rowed the boat. They rowed for three days, pulling at the line until they finally pulled up the largest of the Hawaiian Islands.
At the fiery heart of the Scorpion lies the brilliant star Antares, the 12th brightest star visible from the US. Antares shines with a distinctive yellow-orange flow, reminiscent of Mars. It is that similarity in color that gives Antares its name. Antares comes from the Greek phrases "against Ares," Ares being the Greek version of the god of war that Romans called Mars.
Mars often passes close to Antares, and the color and brightness of the two are so similar that the name of the star reflects that resemblance. This year, Mars and Antares will appear to be close in late November. But the sun will also be nearby, so you'll have to wait until mid-November, 2010, to see the two close together in the night sky.
Antares is a type of star that astronomers call a red supergiant. It once was an ordinary star, just a bit larger in diameter than our sun but 15 times as massive. Massive stars burn through their stellar fuel more quickly than smaller stars, in much the same way that a big sport utility vehicle burns more fuel per mile than a tiny subcompact.
Near the end of their lives, a massive star, starved for fuel, begins using scarcer fuels. These fuels cause the star to swell, and it becomes a red supergiant. Antares is in that stage now. If you put Antares where our sun is, its edge would reach almost to Jupiter!
The final stage of a red supergiant occurs when it runs out of fuel completely. With no fuel left, the star collapses in on itself. Since it is so large, it falls inward with tremendous energy smashing together then shattering from the impact. The star is blown apart in a supernova explosion.
We don't know exactly how close Antares is to becoming a supernova but it will be soon (on a cosmic time scale), and it will be dramatic easily visible in daylight for days or weeks.
Mercury is the most elusive of the naked-eye planets, always hanging close to the sun and never visible in a dark sky. Mercury makes one of its best appearances of the year starting today - July 1st, 2008. "Best appearance" for Mercury does not mean it's easily seen. But for the next week or so, it will be rising about an hour before the sun in the east. You'll need a clear view of the eastern horizon to have a chance of spotting it.
The evening of July 10th, mars will pass within a moon's diameter of Satgurn low in the western evening sky. Although they will be easily distinguished, they are the brightest two objects in that part of the sky and should make an interesting sight.
Look to the west as soon as the sky begins to darken. Mars will be the slightly fainter one with a noticeable yellow or orange tint to it. Saturn, the higher one, will look white. if you have a telescope, take a look. If you don't have a telescope, you can head out to your nearest planetarium.
From july 26-29, 2008 - Earth will pass through a cloud of tiny bits of dust and pebbles, debris from an unknown comet. These tiny bits of cometary debris hit our atmosphere at speeds up to 70,000 mph. At such speeds, they create great frictional heat with our air, causing the rock and the air around it to glow, what astronomers call a meteor. With as many as 20-25 meteros every hour, this debris cloud creates the Delta Aquarid meteor shower.
It's not a great meteor shower, but with no moonlight, you'll have a chance to see them. For the best view, get away from city lights and look after midnight.
A month from today, August 1, 2008, there will be a new moon. That new moon will pass directly between Earth and the sun, creating a total solar eclipse. But you'd better start planning now if you want to see it. It will be visible in Siberia, Russia, and extreme northern Greenland, but not here in the U.S.
The king of planets will shine brightly in Sagittarius. Venus will move farther from the sun and by month's end can be seen as the brilliant "Evening Star" in the west just after sunset.
Venus will climb higher in the west through the remainder of the year.
Mercury may be glimpsed in morning twilight before sunrise in the east.
New moon will occur Thursday; full moon will be July 18th, 2008.
