See a Celestial Summit Meeting

See a Celestial Summit Meeting
On Saturday morning, October 6th, 2007, Venus, Regulus and Saturn will form a wide triangle with the Moon hovering high above them.

The brilliant planet Venus arrives at the pinnacle of itscurrent morning apparition next week, rising at, or shortly before 3:20 a.m.local daylight time, its earliest rising time this year or next. That works outto more than two hours before the first sign of dawn begins to light up theeastern sky.

At sunrise, Venuswill have climbed nearly 40 degrees above the east-southeast horizon (10 degreesis roughly equal to your clenched fist held at arm's length. So at sunup, Venuswill stand nearly "four fists" up from the horizon).

Next week, an ever-changing "Celestial SummitMeeting" will greet early risers as Venus interacts with Regulus, Saturnand a lovely crescent Moon in some very interesting celestial configurations.

Saturn, in contrast appears much dimmer – about 1/120 asbright as Venus – primarily because it's located about 17 times farther out inspace than Venus as seen from here on Earth.

And although it shines only 1/229th as bright as Venus andranks at the bottom on the list of the 21 brighteststars, we know today that Regulus is also regal in an astrophysical sense. It'sa highly luminous blue-white star, and just as earthly kings were uncommonpersonages among the human population, a star like Regulus is also uncommonamong the stellar population. Its spectral class is B7; one of the very smallminority of those born with enough mass to occupy an exalted station near thetop of the main sequence of star classification.

Joe Rao serves as an instructor and guest lecturer at New York's Hayden Planetarium. He writes about astronomy for The New York Times and otherpublications, and he is also an on-camera meteorologist for News 12 Westchester, New York.

Joe Rao
Skywatching Columnist

Joe Rao is Space.com's skywatching columnist, as well as a veteran meteorologist and eclipse chaser who also serves as an instructor and guest lecturer at New York's Hayden Planetarium. He writes about astronomy for Natural History magazine, Sky & Telescope and other publications. Joe is an 8-time Emmy-nominated meteorologist who served the Putnam Valley region of New York for over 21 years. You can find him on Twitter and YouTube tracking lunar and solar eclipses, meteor showers and more. To find out Joe's latest project, visit him on Twitter.