What's Up? with the StarGeezer

My Best Astronomy Experiences of 2011

 

As 2012 dawns, I've been reflecting on my "Best Astronomy Experiences of 2011". Read my "Best of" list and vote on NASA best accomplishment for the year.

Image left: Asteroid Vesta taken by NASA's DAWN spacecraft

Groundhog Day

February 2nd is "Groundhog Day". Legend has it that if "Phil" or any of his cousins pops out and sees his shadow we're in for six more weeks of winter weather. This legend is rooted in the fact that February 2nd is a "cross quarter" day, the midpoint of the winter season. The seasonal equinox, solstice and cross quarter dates mark the comings and goings of the seasons.

Important dates for 2012 are: Vernal equinox, March 20 (first day of Spring), Summer solstice, June 20 and Autumnal equinox on September 22nd. Cross quarter days for Spring, Summer and Fall, 2012 are, respectively, May 5th, August 6th and November 7th. Astronomically, its all about the relative position of the Sun in our sky and the changing of the seasons.

Here is a nicely done chart for 2012 from Archeoastronomy.com and a link to Groundhogday.org

There's more "hoopla" surrounding February 2nd, winter's cross quarter day, I suppose, because we're spending most of the time indoors waiting for Spring. I understand Kevin Harned and John Belski are visiting Punxsutawney, PA to see how things go for "Phil". Have fun, guys!

 

The latest sunrise

Although the days have been getting longer since the December 22nd solstice, we're having our latest sunrises now and Earth is closest to the Sun.  By the end of the month we'll have gained nearly an hour of daylight.

Read more at StarGeezerAstronomy

Watch the skies for Quadrantids Wednesday morning

If you can brave the cold, bundle up and watch the Quadrantid meteors Wednesday morning, January 4th. Best viewing time will be between 3 AM local time, when the moon sets, and dawn.

The "radiant", the apparent point of origin of the meteor stream, will be above your northern horizon near constellation Draco. Wear several layers of clothing and watch the darkest part of your sky.

For more: NASA Quadrantids

Watch the Moon meet Venus December 26th

The two-day old crescent new Moon will glide past brilliant Venus on Monday evening, December 26th.

Read how to enjoy the show at StarGeezerAstronomy

"Christmas Comet" survives encounter with Sun

A tiny comet recently discovered by Australian amateur astronomy Terry Lovejoy survived an intense encounter with the Sun on December 16. It just may be visible through early January at sunrise but you'll need to be south of the equator.

This image of comet C/2011 W3 Lovejoy was taken December 21st by Expedition 30 Commander Dan Burbank aboard the International Space Station. Courtesy D. Burbank/NASA

For details on this story visit StarGeezerAstronomy

Winter Solstice, December 22nd

December 22nd marks the winter solstice in the northern hemisphere and the summer solstice south of the equator. It's the first day of winter here in the north, the first day of summer in the south. Here in the northern hemisphere the solstice is the "shortest" day of the year with the fewest hours of daylight. On Thursday the days will start getting longer.

 You might have the impression that the days are already getting longer and that is because the earliest sunsets were the first two weeks of December. Sunsets are already happening a minute or two later. The order of events at winter solstice is earliest sunset, shortest day then latest sunrise which will occur January 5th.

At the December solstice the northern hemisphere is tilted away from the Sun, the southern tipped toward our star. At the spring and fall equinoxes the Sun is above the equator. This is the reason we have seasons! Interestingly, Earth is closest to the Sun on January 4th and furthest on July 4th!

Watch the Geminid meteors

The Geminid meteors peak Tuesday and Wednesday nights, December 13 and 14. Unfortunately this year the waning Moon will compromise the number of meteors you'll see. Rates for this shower average 85-130 meteors per hour. Skyglow from the Moon will limit visibility to only the brightest meteors.

You can observe the Geminids anytime after mid-evening but the best time will be in the hours before dawn. Shield yourself from the Moon and nearby lights and watch the darkest part of the sky. When you see a "shooting star" trace it's path. If it's a Geminid that line will take you to a point in the constellation Gemini which will be to the right of the Moon on Tuesday and Wednesday nights.

Bundle up and dress warmly when you go out, remember its December. Geminids are among the best showers of the year and relatively bright so even with the glare from the Moon you should see the brightest ones.

Read more here on NASA Science News

NASA has a new Meteor Counter App for iPhone

Watch for a meteor "outburst" Saturday evening

 

Watch for a possible outburst of Draconid meteors Saturday evening, October 8th. Read more here .

A special anniversary for Neptune

 

With a prediction by Frenchman Urbain Le Verrier, telescopic observations confirming the existence of a major planet were made on the night of September 23, 1846, and into the early morning of the 24th, at the Berlin Observatory, by German astronomer Johann Gottfried Galle, assisted by Heinrich Louis d'Arrest, working from Le Verrier's calculations. In François Arago's apt phrase, Le Verrier had discovered a planet "with the point of his pen."

Here comes Fall!

  Friday, September 23rd brings the Autumnal, or Fall, equinox. The exact moment of the equinox will be 9:06 Universal time or 5:06 am EDT in the Americas. At that moment the tilt of Earth's axis will cause the Sun's apparent position to glide across the equator into the southern hemisphere. The Fall equinox marks the beginning of the Fall season in the northern hemisphere and Spring south of the equator.

At the equinox of the seasons I always recommend that you observe sunrise or sunset and make a mental note of the Sun's position on your horizon. Do the same around the winter or summer solstice and compare your observations!