Venus transit Tuesday offers twice-in-a-lifetime event
Published: Friday, June 1, 2012 at 12:19 p.m.
Last Modified: Friday, June 1, 2012 at 12:19 p.m.
In celestial terms, Venus is like Earth's twin; make that its evil twin.
Safe ways to view the transit
“Eclipse glasses” available from various online distributors; these look like the old 3-D glasses, but have specially coated lenses to filter out harmful glare. They do not seem to be available locally.
A piece of No. 13 or (preferred) No. 14 welder's glass; regular sunglasses are not sufficient. A 4-inch-by-5-inch piece of this glass can be purchased at Airgas welding supply stores in Gainesville and Ocala for less than $15.
A pinhole projection onto a second piece of paper, standing with your back to the sun; a shoebox used as a “camera obscura” helps block surrounding light.
Free public viewings, weather allowing. Weather.com forecasts partly cloudy skies for Gainesville on Tuesday with a 20 percent chance of rain.
In a recliner at home, watching a live webcast.
Do not use sunglasses, mylar not rated for eclipse viewing, smoked glass, combinations of lower density welder's glass or sunglasses, liquid filters, older occular solar filters, X-ray film or film negatives. Do not look through unfiltered binoculars or telescopes. Do not look directly at the sun.
University of Florida Astronomy Department, east end of band shell field (FLAVET Field), Museum Road; transit begins at 6:03 p.m.
Kika Silva Pla Planetarium, Santa Fe College, 3000 NW 83rd St., north sidewalk of Building X; events begin at 3 p.m. with talks by planetarium coordinator James Albury
Alachua Astronomy Club, Newberry Star Park at Easton Newberry Sports Complex, 24880 NW 16th Ave., Newberry; transit begins at 6:03 p.m.
www.exploratorium.edu/venus/ — from Mauna Loa Observatory in Hawaii; begins at 5 p.m. eastern time
venustransit.nasa.gov/2012/transit/webcast.php — from Mauna Kea Observatory in Hawaii; begins at 5:45 p.m. eastern time
www.slooh.com/transit-of-venus/ — from SLOOH Space Camera; begins at 6 p.m. eastern time
www.astronomerswithoutborders.org/projects/transit-of-venus.html — from Mount Wilson Observatory in California; begins at 5:45 p.m. eastern time
www.ccssc.org/transit2012.html — from Coca-Cola Space Science Center, Columbus State University in Georgia; begins at 5:30 p.m. eastern time
Consider the similarities: Earth's diameter is barely 600 kilometers more than Venus, and the two planets are not that far apart in surface area.
Yet where Earth sustains life, Venus would be toxic. Its atmosphere is mostly carbon dioxide and sulfuric acid, surface temperatures melt lead and the atmospheric pressure is a crushing 92 times that of Earth's, according to NASA.
"Every probe that makes it to the surface doesn't last more than a few days," says Virgil Lasaga, a "serious amateur astronomer" in Ocala.
So it's easy to see why Venus is not the vacation destination of the universe.
Then why the sudden focus on the second rock from the sun?
On Tuesday, for about seven hours — just under two-and-a-half locally — Earth will be lined up to witness Venus traverse the face of the sun, a solar conjunction that occurs only twice eight years apart every 100-plus years.
The last time in the current cycle was 2004; it won't be seen again until 2117.
The event will be visible to most of the U.S. until sunset Tuesday.
The editors of Sky & Telescope write the transit "takes ‘rare' to a new level. Don't miss next week's chance to see this, because you'll never have another chance in your lifetime."
Since the invention of the telescope, the transit's been viewed only six times: 1639, 1761, 1769, 1874, 1882 and 2004.
Typically, we see Venus only as a brilliant, twinkling pinpoint in the night or morning sky.
But for these few hours Tuesday, it will appear as a tiny black dot slowly crawling across the setting sun.
The transit could be seen with the naked eye. But don't try it, warn astronomers. Looking directly into the sun without filtering can result in permanent eyesight damage or even loss, much like looking directly into a solar eclipse — or the sun itself.
Even at nearly 93 million miles from Earth, "the sun is so bright, it can overload the optic nerve and within minutes of staring at it you could go blind," notes James Albury, coordinator of the Kika Silva Pla Planetarium at Santa Fe College.
He and his colleagues at the University of Florida Astronomy Department and the Alachua Astronomy Club — as well as Sky & Telescope, NASA and every other astronomy website — suggest other ways to safely view the transit that begins in Gainesville at 6:03 p.m.
Among the techniques:
"Eclipse glasses" available from online distributors; some look like the old 3-D glasses, but have specially coated lenses to filter out harmful glare.
A piece of No. 13 or No. 14 welder's glass; regular sunglasses are not sufficient. A 4-inch-by-5-inch piece of this glass can be purchased at Airgas welding supply stores in Gainesville and Ocala for less than $15.
A pinhole projection on a piece of paper; a shoebox used as a "camera obscura" helps block surrounding light.
Free public viewings; UF Astronomy, the Kika Silva Pla Planetarium and the Alachua Astronomy Club are hosting viewings, weather allowing.
In a recliner at home, watching a live webcast.
After the phenomenon was discovered by astronomer Johannes Kepler in 1629, it became a valuable tool allowing scientists to measure the distance between planets using a parallax method.
Attempts to do this in the 1700s now are considered "the Apollo project of the 18th century."
It defined the scale of the solar system, says Andy Howell, vice president of the Alachua Astronomy Club.
These distances are known nowadays and there are other ways of measuring celestial gaps, "so this is not really used for research now," notes Dr. Francisco Reyes of the UF Astronomy Department. "Some groups may use it for educational purposes or an exercise. But it is something very rare, very interesting."
The UF department will set up several telescopes at band shell field on campus.
Lasaga says he'll be set up in his backyard to privately view the transit.
"I've been waiting 31 years for this," he adds.
Barbara Stanson, another Ocala amateur, says she's taking off a half-day to go to Yankeetown for "a clear western horizon."
"I'm pretty sure there will be people at every public beach from Yankeetown south," she adds.
"It's the grandeur, the spectacle and the rarity that makes this stand out," says Howell, a self-described "serious amateur hobbyist."
His club will have several telescopes set up at the Newberry Star Park behind the Easton Newberry Sports Complex.
At the Santa Fe planetarium, telescopes will be set up on the sidewalk outside of Building X, says Albury, a co-host of PBS series "Star Gazers"; in the current episode airing through Sunday, he and co-hosts talk about the transit.
After sunset, folks can move inside and continue watching via webcast.
This transit is so rare, he says, because Venus has a tilted orbit compared with Earth's, and circles the sun faster than Earth does.
"When I sit back and contemplate what is happening," Albury adds, "it gives me a deeper sense of wonder about the cosmos. It's going to be quite exciting … at least for we astronomy folk."
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