27 August 2008

Biodynamic Astronomy Lecture and Star Party on September 6th

Over the past many years I've made several visits to a biodynamic farm called Live Power Farm. The children at San Francisco Waldorf School have a tradition of going there to learn about farming and as a parent on several of these trips I have had a chance to get to know the farmers at Live Power Farm and the approach they embrace, biodynamic farming. It relates to astronomy because it is a very natural and harmonious approach to working with soil, seed, sun and the cycles of nature. As a member of the Live Power CSA, I share in the bounty of the farm and enjoy the amazing food they produce every week.

On my visits to Live Power Farm I learned that the farmers are very cognizant of the lunar cycles and planetary positions with respect to the Sun and Earth. They use a well known guidebook by Maria Thun and biodynamic calendars to guide their work on the farm and I was fascinated to see how farmers worldwide have come to understand cycles in the heavens and use these cycles in their farming. I spent many nights at Live Power Farm talking with the farmers and apprentices about the celestial mechanics of the sky to deepen their appreciation of how these cycles actually come to be.

Saturday September 6th I will be hosting a lecture with Stephen Decater of Live Power Farm. I will share my insights on how to understand the motions of the Moon and planets and how we see their motions from our vantage point here on Earth. Stephen will share his interpretations of these motions and how he works with the cycles in the heavens to guide his work on the farm. Please join us at 7:00 pm for the lecture and 8:30 for star gazing and telescope viewing of the skies. This event takes place at the Marin Waldorf School and is being sponsored by Live Power Farm, San Francisco Waldorf and Marin Waldorf Schools. I hope to see you there.

05 August 2008

KFOG Broadcast: August 5th, 2008

Dance of the Planets

The evening sky in August and September will feature a terrific display of planets, stars and the moon in an elegant dance just above the horizon shortly after sunset. This interplay of planets is a chance to become familiar with the motions of the planets, particular the closest three (Mars, Venus and Mercury) in stark contrast with the motion of the stars and Saturn.

Sky and Telescope has an impressive animation
showing the motion of the objects in the evening sky from the start of August until the end of September. The stars move a small distance closer to the horizon every evening of the year, but the planets move from the west toward the east in their orbit around the sun.

04 August 2008

Perseids Meteor Shower

While observing in the mountains two weeks ago I saw several meteors streak across the sky. Meteors are always a joy to watch because they appear completely without warning yet are so brilliant to see. Seeing one is the reward for keeping focused on the sky and keeping your eyes open and attentive. Every night of the year there are many meteors to be seen but throughout the year there are particularly intense periods of meteor activity called Meteor Showers. The biggest show of the year is the Perseids Meteor Shower which peaks this year during the morning of August 12th. StarDate Online has a helpful list of meteor showers throughout the year and provides some insight how they happen.

There are two simple guidelines for observing the Perseids. First of all you want to be in a dark location with a clear view of the eastern sky. From San Francisco there is a great deal of light pollution which will obscure many of the meteors. The brightest meteors will still be visible but the rate will be considerably lower than the 1-meteor-per-minute rate you would see in very dark skies. So if you want a good view, drive east away from urban centers. Second of all, you want to view them in the early morning hours when the earth is speeding into the spacedust that makes up the meteor shower and when the moon has set. The best viewing should be from 2 AM until 4:30 AM. NASA has a helpful page showing where to look in the sky. During the early morning hours the rate will increase up to a maximum of 1 per minute.

02 August 2008

Great eclipse images

The total solar eclipse of August 1st was well documented. Sky and Telescope has a nice gallery of pictures. I find that photos can't really do justice to the real thing, but a collection of photos like those on Sky and Telescope are interesting if taken in total -- that is, look at many of them and imagine seeing all of these images at the same time with your eye. That is what it is like at an eclipse. Your eye can see a lot more shades of brightness than a camera and besides the visual spectacle of an eclipse, being there is an unforgettable experience.

A colleague showed me this amazing view of the total solar eclipse from an airplane. The most intriguing thing to me is the way the shadow of the moon looks from the vantage point of an airplane and how it moves from north to south during the very short period of totality. It must be a very eerie sight to see in person.

Astrophotographer Dennis diCicco takes excellent photographs and this depicts him at work in China.This image gives you a sense of what it looks like to be there with a dusk-like but not dark sky. You can see Mercury and Venus to the upper left of the sun-moon pair.

The Exploratorium had its usual great coverage of the eclipse live from China. The video is now available for replay on their website. It is a great resource if you want to get an idea of what it is like to be at an eclipse.