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| DATE | 2005-10-29 |
| FROM | Ruben Safir
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| SUBJECT | Subject: [NYLXS - HANGOUT] Halloween Mars
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Tonight, Mars puts on
quite a show
By BOB ARNDORFER
Sun staff writer
October 29. 2005 6:01AM
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Picture
ZOOMzoom
NASA/The New York Times
Mars is seen through the Hubble
Space Telescope on Aug. 27, 2003.
o, it's not the Great Pumpkin, Charlie Brown.
In a prologue to Halloween, the Red Planet - actually it looks more the
color of a jack-o'-lantern - tonight will make its closest pass by Earth
until 2018. And in a special telescope-viewing at Santa Fe Community
College beginning at 8 p.m., the public will have a chance to see the
best show on Mars in years.
Many normally obscure features of the Martian surface should be clearly
visible through telescopes, said Sally Hoffman, the Santa Fe Community
College astronomy professor who is hosting tonight's event. They include
the Hellas Basin - a 4 billion-year-old impact crater - Mars' polar
caps, the mysterious greenish-gray markings that led to the myth of
"little green men" inhabiting the planet, and maybe even a Martian
sandstorm.
"The view of Mars this year promises to be much clearer than in 2003,
even though the approach in 2003 was the closest in 100,000 years,"
Hoffman said.
The phenomenon that's causing all the Martian fuss is called
"opposition," which occurs when Mars in its orbit is exactly opposite
the Earth from the sun. It occurs every two years, but some years the
Red Planet is closer to Earth because of the vagaries of its oval-shaped
orbit.
Hoffman said tonight at 11 Mars will be about 43 million miles from
Earth. During the 2003 opposition, it was about 34 million miles away.
By comparison, the moon is about 240,000 miles from Earth.
Mars will rise in the eastern sky, she said, and by about 7 p.m. should
be visible even to people who have trees blocking their view of the
horizon. It will be unmistakable in its distinctive orange color as it
rises almost overhead.
With the naked eye, Hoffman said, Mars will be interesting in its
brightness, but few features will be visible.
Through a telescope, however, this year's show should be better than
2003 - when Mars appeared about 20 percent larger than it does now -
because the planet is almost twice as high in the sky than it was two
years ago.
"When it's lower in the sky as it was in 2003, you're looking through a
lot more of our atmosphere to see it," said Hoffman, who will give
visitors Mars maps at tonight's free program. "This time it's about 30
degrees higher at its highest point, so we're looking through just a
small portion of our atmosphere."
The much-ballyhooed 2003 opposition was marred by other visibility
problems, she said, including a giant global Martian sandstorm that
obscured much of the planet's surface features.
Although Mars' distance from Earth is closest at 11 tonight, Hoffman
said, actual opposition won't occur for about another week.
"Opposition does not occur at the same time as closest approach," she
said. "It will be at perfect opposition on Nov. 7."
The beauty of opposition, compared with, say, a solar or lunar eclipse,
is that it lasts much longer - weeks instead of minutes. Hoffman said
Mars will be near opposition until the end of the year.
That means the show in a couple of weeks will be as good as tonight's;
if it's cloudy or raining tonight, Hoffman said, the SFCC event will be
rescheduled for the same time next Saturday.
And in two weeks there will be another opportunity for the public to see
Mars through telescopes.
The Florida Museum of Natural History and the Alachua Astronomy Club
will sponsor "Magnificent Mars" on Nov. 12 - coincidentally on the
anniversary of Orson Welles' infamous 1938 radio broadcast of a Martian
invasion, "War of the Worlds."
The free program will feature presentations and telescope viewings of
Mars and other celestial bodies.
What won't be seen during this or any other Mars opposition is the Red
Planet the size of a full moon, as has been suggested on the Internet.
That, like little green men, is a myth.
Bob Arndorfer can be reached at 374-5042 or arndorb-at- gvillesun.com
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