Jan 21, 2003

The Hour of the Planets




Dashing out the door to work or school? Pause for a moment and look up. There are two dazzling planets in the morning sky.





Link to story audio
Listen to this story via , a , or get help.


show caption
January 21, 2003:  John Steinbeck called it "the hour of the pearl."


It's "the gray time," he wrote in Cannery Row, "after the light has come and before the sun has risen--the interval between day and night when time stops and examines itself. No automobiles are running then. The streets are silent of progress and business. And the rush and drag of the waves can be heard as they splash in among the piles of the canneries."

Right: Photographer Sho Endo snapped this picture of Venus rising above the waves of Japan's Pacific coast before sunrise on Jan. 11, 2003.

That was 50 years ago. Nowadays the hour of the pearl is announced by ringing alarm clocks. It's when you drag yourself out of bed, rush to get dressed, grab a hasty breakfast. And what's that distant roar? The sound of the freeways.

So let's call it something different: "The hour of the planets."




Sign up for EXPRESS SCIENCE NEWS delivery
There are two bright ones in the dawn sky this month: Venus and Jupiter. Even after all the other stars and planets have begun to fade against the brightening sky, these two are absolutely eye-catching. And it only takes a moment to enjoy them as you dash out the door to work or school.

First, glance toward the southeast in the direction (more or less) of the rising sun, and you'll spot Venus (magnitude -4.4) shining 140 times brighter than a first magnitude star. Venus is often mistaken for a UFO or a landing airplane, but it you pause for a long look, you'll see that it doesn't move like either of those. It's as still as the morning streets of Cannery Row. (Actually, Venus does move; it rises slowly like the Sun. Keep an eye on it from dawn onward. If you know where to look, you can see Venus in broad daylight.)

Next, spin around and look west. There's Jupiter (magnitude -2.4), about the same distance above the horizon as Venus is. Although Jupiter is much bigger than Venus, it is 6 times farther away from Earth and correspondingly dimmer. Even so, Jupiter is 25 times brighter than a first magnitude star--very impressive.


show caption

Above: Venus and Mars are easy to spot in southeastern sky at sunrise. Note that Mars and the nearby star Antares both have a coppery hue and are easily confused. A similar

shows where to look for the giant planet Jupiter.


If you do have time to spare, and a small telescope, take a closer look at Jupiter and Venus.

Jupiter is very rewarding. You'll be able to see its rust-colored cloud belts with ease. First-time observers often note that the planet looks squashed--wider along the equator than between the poles. Is there something wrong with the telescope? No. Jupiter really is flattened. Although Jupiter is 70 times bigger around the middle than Earth, it spins more than twice as fast; a day on Jupiter lasts only 9 hours and 55 minutes. This rapid spin is what gives Jupiter its equatorial bulge. Small telescopes will also reveal up to four "stars" around Jupiter. Galileo using only a primitive spyglass saw them first in 1610. They are Jupiter's moons: Io, Europa, Callisto and Ganymede. Finally, the Great Red Spot (GRS)--a cyclone twice as wide as Earth--is also frequently visible. Experienced observers note that larger (10-inch) telescopes and clear steady skies are essential for good views of the GRS.


show caption
Right: Amateur astronomers Dennis Pang and Eric Ng of Hong Kong captured this image of Jupiter on January 18, 2003, using a 10-inch telescope and an inexpensive digital camera.


Although Venus is brighter than Jupiter, it seems less impressive through a telescope. Why? Because Venus is enveloped by thick and utterly featureless clouds. For many years, scientists suspected that Venus's clouds hid a tropical paradise, but now we know, thanks to radar studies and Russian spacecraft that have landed there, that Venus is a hellish wasteland. The surface of Venus is dryer than any desert on Earth and hot enough to melt lead. And those clouds? They are laced with sulfuric acid.

None of that is apparent in the eyepiece of your telescope, though. Venus looks rather pacific and bland. You might note that Venus isn't a complete circle. Like the Moon, Venus has phases, and at the moment it is waxing gibbous, a little more than a half full. More than anything, though, Venus looks like a distant pearl: white, serene, a relaxing sight.

Maybe Steinbeck was right. It is the hour of the pearl, after all.



Editor's note: In recent weeks, Jupiter has become a prominent evening planet, too. Look for it in the east after 8:00 p.m. local time. Also, mark Tuesday, January 28th, on your calendar. That's when the slender crescent Moon (with Earthshine) will glide by Venus in the morning sky--a lovely pairing.

Web Links

Bonus planet: While you're looking at Venus, can you see a red star nearby? That's Mars (magnitude +1.4). The red planet is much fainter than Jupiter or Venus, but it is brightening every day. Earth and Mars are drawing closer together and by August, 2003, Mars will shine 30% brighter than Jupiter does now. Glance at Mars. Glance at Jupiter. Imagine the red planet that bright.

John Steinbeck won the 1962 Nobel Prize in Literature for Cannery Row and other works.


Join our growing list of subscribers - sign up for our express news delivery and you will receive a mail message every time we post a new story!!!


says 'NASA NEWS'