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The Honolulu Advertiser
Posted on: Sunday, January 27, 2008

Close encounters of the bright-planet kind

By Carolyn Kaichi
Bishop Museum

The first day of the month starts off with a beautiful planet pairing in the eastern sky. Early in the morning, the two brightest planets, Venus and Jupiter, rise together before the sun with a small waning crescent moon in attendance.

The two planets have been drawing together over the past couple of weeks and on Friday will be the closest together from our point of view.

Venus is 338 million miles closer to us than Jupiter and much smaller (more than 1,000 Venuses would fit inside Jupiter), yet it outshines the larger planet. Venus has a thick blanket of sulfuric-acid-laced clouds that is highly reflective, and its proximity to the sun also contributes to the inner planet being more than 6 1/2 times brighter than Jupiter.

But Jupiter is still larger to the eye and its family of four "Galilaen satellites" is fascinating seen through a small telescope or binoculars. Jupiter actually has 62 known moons of varying sizes and distances from the planet, but the discoveries of the four largest are attributed to Galileo Galilei almost 400 years ago.

Using a telescope not much stronger than toy-store models of today, Galileo observed the orbits of the Jovian moons in 1610 and proved that the Earth is not the center of the universe, as was widely believed in his time.

The two formidable planets will dominate the other points of light in the morning sky for the next few days, rising a little after 5 a.m. during the first week of February. But while they rise as a pair on the first day, Jupiter slowly begins to pull away from Venus as the brighter planet begins to move closer to the sunrise.

Venus is on its way to becoming an evening planet again, and the process will be a slow progression that will eventually bring Venus back to the night sky in mid-summer.

Being the most obvious lights in the night next to the moon, Venus and Jupiter have references in almost every ancient civilization, but the names we know today come from the Romans.

Venus, whose counterpart in Greek myth is Aphrodite, is associated with love, beauty and fertility. And in many other cultures, the planet is also seen as a strong and important symbol. Because the movement of the inner planet results in it being visible either as a morning or an evening "star," many early cultures gave Venus two separate names.

Among the many names in the Hawaiian language for this planet, Hokuao and Hokukauahiahi are two for Venus in the morning and evening, respectively.

Jupiter, the second-brightest planet and having the largest apparent diameter, also commands attention. Named for a Roman god, its mythological counterpart is Zeus, king of the Greek gods residing atop Mount Olympus. Jupiter the planet spends about a year in each of the constellations of the zodiac, taking 12 years to circle the sun, and that may have contributed to the ancients associating it with a powerful god's name. The Hawaiians called this planet 'Ikaika, a name describing strength or power.

FEBRUARY ECLIPSES

A solar and lunar eclipse happen in February, although we will only be able to catch the ending of the lunar eclipse.

The solar eclipse starts Feb. 6 at 5:20 p.m., but will be visible only in the lower southern hemisphere — in New Zealand, southeast Australia and Antarctica.

The eclipse will be an annular type, where the moon will not totally cover the sun, but will leave a ring of sunlight around the disk of the moon during the height of the event. Although the shadow will cover parts of the Pacific, we will not be able to see even a partial eclipse at our latitude.

The lunar eclipse will be visible from Hawai'i, but not under the best circumstances.

The moon will be out of the total phase of the eclipse when it rises at 6:30 p.m. Feb. 20. However, the partial phase will last until around 7 p.m. We will still be in twilight for most of that time, but if you are interested in seeing the eclipse, you should be in an area where you can see the moon as it rises (facing east).

THE PLANETS

Earth:

February gains an extra day this year. Leap year is the result of astronomical time not quite aligning with our current calendar, based on the solar day. We add the extra day to compensate for the differences.

Mercury:

Look for great images to come from the Messenger spacecraft as NASA downloads them from the recent flyby in January.

Eventually, Messenger will settle into orbit around the tiny planet to complete its mission in 2011 (see messenger.jhuapl.edu).

To see Mercury in the sky, look for it low in the east after the second half of the month before sunrise.

Venus:

Rising with Jupiter in the first week of the month a little after 5 a.m., Venus will rise with Mercury by the end of the month, a half-hour later.

Mars:

Mars is high in the sky by the time darkness falls in February. It's still relatively bright, although the first- and second-brightest stars in the sky already outshine it: Sirius, in Canis Major, is below Orion not far from the Red Planet, and Canopus sits low in the southern sky.

Mars is in the constellation of Taurus and close to Orion; both constellations contain red-orange stars that can be contrasted with the orange hue of Mars. This is also a good opportunity to see the difference between the glittery appearance of the stars Betelguese (in Orion's shoulder) and Aldebaran (eye of Taurus) and the steadier glow of the planet.

Jupiter:

After their rendezvous in early February, Venus and Jupiter go their separate ways. While Venus rises later during the month, Jupiter rises earlier. By the end of the month, the largest planet rises an hour later, at 4 a.m. in the constellation Sagittarius.

Saturn:

Saturn rises at around 7:30 p.m. at the beginning of the month then is at opposition on Feb. 24, rising as the sun sets and remaining in the sky all night. On the night of the lunar eclipse (Feb. 20), the moon will be rising close to the ringed planet to offer a nice telescopic addition to your evening.

MOON PHASES

New moon: Feb. 6

First quarter: Feb. 13

Full moon: Feb. 20

Third quarter: Feb. 27

Questions? Contact Carolyn Kaichi at 847-8203 or hokupaa@bishopmuseum.org.

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