Isles best seat for Mercury transit

Webcasts from the observatories will share Wednesday's event with the world

Hawaii will be on a world stage Wednesday, with the best view of a rare celestial event.

The smallest and densest of the terrestrial planets, Mercury will pass directly in front of the sun for five hours starting at 9:12 a.m.

Islanders won't be able to see the tiny planet's transit without telescopes -- nor should they try with the naked eye. But they will have access to real-time images of the event from Mauna Kea and Haleakala on a "Mercury Transit Hawaiian Style Webcast" on the Internet.

The University of Hawaii Institute for Astronomy, UH-Hilo Physics and Astronomy Department and Haleakala Amateur Astronomers will produce the webcast.

Kalama Intermediate School students will be on Haleakala with the amateur astronomers to observe the event and help capture it through images.

Scientists from Williams College in Massachusetts and the University of Arizona will join UH solar astronomers to study Mercury's progress across the sun with a special instrument on the telescope in the Mees Solar Observatory, Haleakala.

Hawaii is in a prime location not just to see the transit, "but to share it with the world with the best possible viewing configuration," said Gary Fujihara, science education and public outreach officer, UH Institute for Astronomy, Hilo.

"The cool thing about it," he said, "we've been getting inundated with calls from around the world, including organizations and institutions such as the Kitt Peak National Observatory and NASA's Goddard Space Center and other places running webcasts of the Mercury transit."

They're asking for access to images from Mauna Kea and Haleakala because Hawaii is in the middle of the "window of visibility" for the event, he said.

Sets of images will be used for time-lapse movies of the transit that will be updated every half hour. Videoconferences also will be conducted with astrophysicists, astronomers, engineers, students and Hawaiian cultural practitioners.

The moon, Mercury and Venus are the only objects between the Earth and the sun. When the planets between the Earth and sun line up, it's called a transit.

"It will be nice and high up in the sky," Fujihara said. "We should have great weather, great seeing, and because we're in Hawaii and we have lots of aloha, we want to share this event with the rest of the world via the Internet."

The Hawaiian Astronomical Society will have solar telescopes at the Bishop Museum for public viewing throughout the transit. Telescopes also will be available at the University of Hawaii-Hilo, 'Imiloa: Astronomy Center of Hawaii in Hilo and the Mauna Kea visitor center.

Some telescopes also will be set up on the UH-Manoa campus for astronomy students and teachers.

The last Mercury transit in 2003 couldn't be seen from Hawaii, and the next one in 2016 will be visible only for a few minutes at sunset, said Carolyn Kaichi, Bishop Museum planetarium manager.

The next one that can be seen from beginning to end will be May 10, 2062, she said.

"People should be very wary about trying to view it themselves," because they could damage their eyes, Kaichi said.

First, it can't be seen with the naked eye because Mercury's diameter is 194 times smaller than the sun's as seen from Earth, she said. Using some type of pinhole projection method won't work because it doesn't magnify size, she said.

Telescopes must be equipped with a solar filter to protect the eyes, she said. Kaichi encouraged people either to watch the webcast or go to the museum to see the event.

A NASA specialist will discuss the spacecraft Messenger's mission to Mercury on the webcast and "why is it such a weird planet," Fujihara said.

"Forget about Pluto being kicked out of the club. Mercury has a lot of mysteries," he said.

Mercury is the least explored terrestrial planet, and is believed important to understanding terrestrial planet evolution, according to the Messenger mission's Web site. The spacecraft will make three fly-bys of the planet before entering Mercury's orbit in March 2011.

The UH Institute for Astronomy produced a similar webcast in July last year for Deep Impact, the first spacecraft to impact the surface of a comet when it was targeted to crash on Comet Temple 1.

For more information and to see the event live, go to http://astroday.net/MercTransit06.html.