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The Honolulu Advertiser
Posted on: Sunday, September 30, 2007

We move all the time — even while in traffic gridlock

By Carolyn Kaichi
Bishop Museum

I assume every driver has experienced this situation before: being stuck for miles in bumper-to-bumper traffic only to have a mysterious point where traffic starts flowing smoothly with no evidence of any accident or stall.

Perhaps at an earlier time there was a reason for people to slow down at that point, but even after that incident was long over the snarl remains in that space. If the words "time" and "space" in the same sentence makes you think of a documentary on public television, consider that we experience the relationship in some form every day. Whenever I'm stuck in gridlock I try to amuse myself by putting some perspective on this situation.

Even when you aren't moving on the ground, you are moving through space as the Earth rotates on its axis. At the equator the surface is moving at 1,040 mph, decreasing in speed as you move toward the poles.

At our latitude in Hawai'i, approximately 20 degrees north of the equator, we are speeding along over 900 mph. The Earth is also in orbit around the sun—making a full circle in 365 days at the speed of 18.5 miles per second, or 66,629 mph. In addition, the solar system revolves around the galactic center of the Milky Way and the galaxy expands with the rest of the Universe at much faster speeds. The fact remains that the sensation of being "still" is a matter of perspective, although it doesn't seem to matter much when you are late for an appointment.

So what does all this have to do with the "space" that we look at when we're star-gazing? Even though we are traveling though the universe at dizzying speeds, it still takes time to traverse through the astronomical distances of space. The Phoenix spacecraft, launched toward Mars in August of this year, is cruising toward the Red Planet at 74,000 mph. It is scheduled to approach the planet in May —nine months later. Another spacecraft, named New Horizons, has been soaring to Pluto since January 2006 at a speed of 45,000 mph and it still has nine years to go before it reaches its goal.

Beyond our solar system, we examine the nearest star system closest to our sun, a set of stellar triplets known as Alpha, Beta and Proxima Centauri. At around 25 trillion miles away, it takes light going at the speed of 186,000 miles per second over four years to reach there. Now imagine the vehicles we are presently using for human space exploration (as opposed to the unmanned missions I referred to above), the Space Shuttle and the International Space Station as the means of traveling to those stars.

Their orbital speeds are 17,500 mph as they circle the Earth — almost 30 times faster than your average commuter jet. However, even at those speeds astronauts trying to reach Alpha Centauri would take a 162,000-year trip — one way. But there are no planets orbiting this system and the closest extrasolar planet is over twice that distance.

As we see stories on the news about global warming and the changing environment, keep in mind that as of yet we are not going anywhere in the near future. Even as scientists search for more planets or life within our own solar system, we have not yet even discovered any other environment that can support life. Earth is not a "disposable" planet and regardless of whether the climate changes in 50 years or 500 years, finding another home is not the practical option.

ORIONIDS, BIG FULL MOON

Like clockwork, the Orionid meteor shower is back as the Earth runs into the debris field left over from Halley's comet. This year the peak is on Oct. 21 at noon HST. Obviously you won't be seeing any meteors while the sun is directly overhead so I inquired with the local meteor watchers group to find out if there was a preferred time to see the most meteors. The answer was that either the day before or the day after would be equally likely to be best, and predicting which one would be better was difficult. The Moon will be just past first quarter, and will set between 1 a.m. and 3 a.m. on Oct. 20 to Oct. 22, respectively.

From moonset until sunrise, the meteors' "center," the constellation Orion, will be high in the sky and in the best location for meteor-watching. So grab your lawn chair and head out to the darkest spot you can find. The best way to see meteors is to scan around, so pick an area that you can see as much of the sky as possible.

The full Moon this month is the largest full Moon of the year. With the full phase coinciding with perigee, the Moon's closest point in its orbit around the Earth, tides higher than normal are expected.

THE PLANETS

Mercury: Mercury is visible low in the west before sunset the first week of the month, then becomes increasingly lost in the glow of the sun as it heads toward conjunction and into the morning sky by the end of October. If you have a very clear view to the west, however, you may spot a young Moon on Oct. 12 adjacent to the little planet for a brief period before the two set shortly after the sun.

Venus: Bright and steady, Venus shines in the morning sky, rising shortly after 3 a.m. throughout the month as it retrogrades. Because of that, it appears almost stationary and allows for a wonderful grouping starting from Oct. 7 for almost a week. On the 7th, look for the crescent Moon, Saturn, Venus and Regulus (the brightest star in Leo) in a small cluster in the east from around 3:30 a.m. to sunrise. After that date the Moon will no longer be in the mix but the other three bright objects will stay together for at least a week afterward.

Mars: Look for Mars rising in the east around 11:30 p.m. close to a gibbous Moon on the first of the month. This is the beginning of the Red Planet's return to prominence in the night sky-culminating in its Christmas Eve opposition. Mars will continue to rise earlier and become bigger and brighter as the year winds to a close, offering a beautiful view of its orange hues and telescopic features.

Jupiter: Jupiter is slowly and surely leaving the night sky and by December will pass behind the sun to emerge in the morning glow. It is by far one of the more interesting sights in a telescope or binoculars from the city, with its striped clouds and Galilean moons in motion around the giant planet. Watch for a crescent Moon on the evening of Oct. 15 pass between Jupiter and the closest bright star Antares in the constellation Scorpius.

Saturn: Saturn is temporarily losing the luster of its nickname "the ringed planet" as the rings continue to "close," or become edgewise to our line of sight. It's significantly dimmer than it was when it was closer to Earth in its orbit, but it still outshines Regulus, the brightest star in its host constellation Leo. Saturn is close to its brighter sister Venus throughout the month — make sure you check out the close grouping from Oct. 7 - 14.

MOON PHASES

Third Quarter: Oct. 3

New Moon: Oct. 10

First Quarter: Oct. 18

Full Moon: Oct. 25

All dates are Hawai'i Standard time.

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

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