Posted on: Saturday, April 17, 2004

SATURDAY SCOOPS
Scoping out the sky
By Chris Oliver
Advertiser Staff Writer

Jim Harwood, a retired professor of astronomy, will be on hand at the Amateur Telescope Clinic tomorrow at the University of Hawai'i Institute for Astronomy Open House in Manoa. He will provide advice on investing in a home telescope. Rebecca Breyer • The Honolulu Advertiser Star party The Hawai'i Astronomical Society will hold a star party April 24, after sundown, at Kahala Community Park and Waikele Community Park. Free. IInformation: 524-2450.

At a Bishop Museum event tied to the close approach of Mars last fall, Jim Harwood found himself approached ... for advice on buying a home telescope. Harwood, a retired professor of astronomy and lifelong enthusiast of the night sky, said he gets plenty of questions about backyard observing from amateur stargazers.

" Look into the Western sky tonight and the brightest object visible is Venus. To the left of Venus is the Orion constellation and looking left again is the 'dog star' Sirius," said Harwood. "The planet Jupiter is almost directly overhead. Though all are visible with the naked eye, a home telescope will magnify details such as Jupiter's moons wonderfully."

For those looking to invest in a "home scope" for the deck or lanai, Harwood will be on hand tomorrow with telescopes and tips at an Amateur Telescope Clinic, part of the University of Hawai'i Institute for Astronomy Open House in Manoa.

" I see a lot of advertisements pushing telescopes with way more power (magnification) than is needed for a home telescope," said Harwood. "I also have a friend in Seattle who repairs small telescopes and has lots of horror stories about incompetent or badly packaged equipment. It just seemed like there was a need to have some information about what was important when buying a telescope for home use.

" People often think that buying a telescope with a high magnification means they're going to see more objects or a greater distance, but it is the diameter of the mirror that is important, not the magnification," Harwood said. "A high magnification will blur images, which then bounce around too much whereas a wide mirror will give a much cleaner picture."

Harwood recommends a reflecting telescope with a 3-to-6-inch-diameter mirror (a reflecting telescope has a mirror with one curved surface; a refracting telescope has a lens requiring several precise curved surfaces).
" The larger the diameter of the mirror, the more telescope you get for your money," he said. "For example, the Edmund Scientific Astroscan has a 4¥-inch mirror with 16x magnification. For $200, it's an excellent family telescope."

With this telescope, Harwood says, it's easy to see the moon and stars quite brilliantly.

" The moon is spectacular. Its shadows are sharp, as are the planets. Saturn's rings and Jupiter's moons, which change from hour to hour, are also good, and the colors are great. Globular clusters look beautiful ... like pinpoints of jewels; there also are ring nebulae — round doughnut-shaped blue and white objects with the original star visible in the center. Then of course comets and asteroids come around from time to time. ..."
Harwood cautioned that home telescopes will not produce images like those seen using the Hubble telescope, which uses a powerful time-lapse camera.

Another tip: Make sure you have a stable tripod or mount. A spindly tripod makes a telescope hard to align, Harwood added.

Is a computer useful? "For a telescope in the $1,000 range, astronomy software programs enable you to click on the object you want to look at and the telescope will automatically find it, saving a lot of set-up time and fiddling around," Harwood said.

Harwood advised doing some simple research before buying a telescope and, most important, to buy one for the whole family. "It's not just a toy for a child, it's fun for everyone ... parents, grandparents and children."