Eyes Full Of Stars

Mars reached opposition to Earth on January 29th, but another solar system object has been gradually making its way into the evening sky, Saturn. In addition to a beautiful ring system, Saturn holds another distinction, it is the most remote member of the solar system easily visible to the unaided eye. Currently located at a distance of about 830 million miles in the direction of the constellation Virgo, Saturn presents a nearly edge-on view of its ring system to earthbound observers.

All kinds of critters roam the night sky including fanciful beasts like dragons, sea monsters, centaurs, a unicorn and a winged horse. Other constellations depict creatures you are likely to encounter on a trip to the local zoo or aquarium. But, did you know that one of the best represented animals is the goat?

In the ancient world, goats were popular livestock. Their hardy constitution and scrappy nature made them the animal of choice to survive rocky, arid and bleak conditions. Goats provided sustenance in the form of meat, milk and cheese. A sea-faring goat is the subject of the zodiacal constellation, Capricornus. But, there are stars named after goats too. To find them we need to turn to the constellation Auriga in the northern sky.

A description that might occur to people seeing Mars through a telescope for the first time. On Wednesday January 27th, the red planet will be the closest it gets to Earth during the current apparition. Of course, 62 million miles isn’t exactly right around the corner. At its brightest, Mars will rival the visual magnitude of the night sky’s most luminous star, Sirius.

Since Mars’ record opposition of late August 2003 when it reached just under 35 million miles distant, all kinds of Mars-related activity has taken place. Some, like the perennial Mars hoax email, have served to increase misinformation common to pop astronomy. Others spurred on by NASA’s Mars Exploration Program mantra of “follow the water”, have yielded a bonanza of new discoveries and the endless series of questions we must answer to explain them.

On January 3rd we reached perihelion in our orbit around the Sun. Perihelion marks the point in Earth’s orbit where our planet is nearest to the Sun. Every year we reach perihelion during the first days of January. Our perihelion distance is about 2 million miles closer to the Sun than our average distance of 93 million miles.

Because Earth’s orbit around the Sun is not circular but elliptical, we are closer or farther away from the Sun at the extreme points of the ellipse. Perihelion’s opposite is known as aphelion and happens each year around the Fourth of July. Because Earth’s elliptical orbit is not as out-of-round, or eccentric, as the orbit of Mars, the effect on us is very subtle.