this weekend

The brilliant planet Venus arrives at the pinnacle of its current 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 out to more than two hours before the first sign of dawn begins to light up the eastern sky.



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

Meanwhile, a much dimmer planet, Saturn, glowing with a mellow yellow light, rises shortly after Venus. And right in between the two planets shines the blue-white 1st-magnitude star, Regulus, in Leo, the Lion.

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

The eye-catching array kicks off this weekend. On Saturday morning, Oct. 6, Venus, Regulus and Saturn will form a wide triangle with the Moon hovering high above them.

On Sunday morning, Oct. 7, the Moon will be strikingly positioned inside of the Venus-Saturn-Regulus triangle.

Venus will appear to speed to the south of Regulus on Monday, Oct. 9. Then finally, on Sunday, Oct. 14, Venus will pass to the south of Saturn.

Crescent Venus

In telescopes and even steadily-held binoculars Venus is revealed this week as a wide crescent, but as it pulls ahead of Earth and speeds away in its orbit, its disk will shrink and it will display an apparent half-moon phase as seen in a telescope, soon after the start of November.

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

Another factor is that the famous ring system, which can be seen in any telescope magnifying over 30-power, is gradually closing as seen from our Earthly perspective. Their angle of inclination diminishes from 8.8 to 7.4-degrees during October. By the summer of 2009, the rings will appear edge-on to us and will be difficult, if not impossible to see, even in large telescopes.

Heart of Leo

As for Regulus, it marks the heart of Leo, a star pattern whose origins trace back to the earliest Mideastern peoples, especially those of the Tigris and Euphrates area. Among virtually all civilizations there, this constellation was accorded king-of-the-beasts status and regal symbolism.



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

And lastly, its distance of 78 light-years means the light you see arriving from Regulus now started on its journey to Earth right around the time of the great stock market crash in 1929.