More Eclipse Information…   Leave a comment

From the previous post, you know the date and time of the solar eclipse… so you just need to look up right? NO!!

You have to be safe!  The ultraviolet rays from the Sun can cause permanent injury to your eyes. You should never stare directly into the Sun. That’s my safety PSA for the day.

So now, how do you safely view the eclipse? You can watch it directly with eye protection, or watch a projection of it on something. Let’s look at them in turn.

Protection: You can use specially made eclipse glasses, solar filters from telescopes or binoculars, or eclipse viewing filters. I wouldn’t use anything else.  Some people use welders glass or film negatives but it is not safe.  But hey, it’s your eyes.

Projection:  The cheapest, easiest way to view the eclipse is  to make a ‘pinhole projector’. Simply take two pieces of cardboard or paper and use a pinhole in one to project the image of the Sun onto the other. You will still see the effect of the Sun with a “cut out” image on the viewing side.

Here’s two web sites for more information:

A good longish video about how to view it safely (7 minutes):

General sun safety page:


In San Francisco, the eclipse will begin at 5:16 p.m. PDT. The maximum eclipse will occur at 6:32 p.m. when 84.22 percent of the sun will be obscured. The eclipse will end at 7:40 p.m.

Posted 14 May, 2012 by tjsummer in Uncategorized

Are you ready for the solar eclipse?   Leave a comment

The 20th of May 2012 will be one of the first solar eclipses for a long time that we have been able to see from California.  Safe viewing tips will be coming up soon. If you want to see what, if anything will be seen from your area, please check out:

or the more easily understood:

If you are in San Francisco, here’s the times to be aware of:

Lat.: 37.7378° N
Long.: 122.4399° W
Partial Solar Eclipse
Magnitude: 0.896
Event Date Time (UT) Alt Azi
Start of partial eclipse (C1) : 2012/05/21 00:15:54.8 033.7° 270.5°
Maximum eclipse : 2012/05/21 01:32:42.1 018.7° 281.5°
End of partial eclipse (C4) : 2012/05/21 02:39:57.3 005.9° 291.1°

For those of you not fluent in NASA speak, in San Francisco, the eclipse will begin at 5:16 p.m. PDT, this Sunday May 20th. The maximum eclipse will occur at 6:32 p.m. when 84.22 percent of the sun will be obscured, then it will slowly come out until 7:40 p.m.   Take advantage of this wonderful moment to share with your loved ones.

Posted 11 May, 2012 by tjsummer in Uncategorized

Astronomy Day – this Saturday!   Leave a comment

If you are in San Francisco, please join Astrono-me! Productions at the California Academy of Sciences to celebrate Astronomy Day, this Saturday 28 April 2012. There will be astronomy activities around the museum all day, and I will be there in the afternoon (around 3) creating pocket solar system models that you can take home with you.  Please stop by!

Astronomy Day started in Northern California in 1973.  It’s a chance for people to get to know the astronomy resources in their community.  It happens every year between mid April and mid May on the Saturday closest to the new moon.  This is so the sidewalk astronomers who set up telescopes for the general public won’t have to deal with the bright full moon blocking the fainter objects from their telescopes.  Most cities have many events going on, so check out what might be going on locally for you.

Happy Birthday, human space flight!   Leave a comment

The date was 12 April 1961. The occasion? The first human being in space!  Cosmonaut Yuri Gagarin circled the Earth in his Vostok spacecraft and safely came back to Earth.

Okay, it was yesterday. But all around the world, people commemorate this historic moment that humanity became citizens of planet Earth.  No longer were we defined by our countries and borders, but by our common home.  That this moment occurred during the space race and cold war between the United States and the Soviet Union is not lost on me.  But the scientific and technological achievement belongs to all of us.  Science has no borders, and the crucial component of it, curiosity, is born in every child. if you would like to take place in one of the worldwide celebrations, visit:


Posted 13 April, 2012 by tjsummer in Uncategorized

GLOBE at night   Leave a comment

Have you heard about citizen science?  It’s the term for when non-professional, scientifically interested people do real scientific research. One of my favorite citizen science projects is GLOBE at night, because you don’t need any special equipment to collect important data:

April is the last chance to participate this year, specifically April 11-20, 2012. A citizen, say, you, measures the sky brightness in your local area. (If you are in San Francisco, your latitude is roughly 38 and longitude is -122.) Looking at an easy to find constellation, in this case Leo the Lion, you report back which stars you can see.  They will give you instructions on determining  your longitude and latitude, as well as how to find the constellation.  It’s that easy! When you report your data, you can compare it to thousands of others around the world.  And when you do it, you are sharing information about a growing problem – light pollution.

Light pollution is when the lights of our cities and structures shine up into the sky rather than down on the ground where we need them.  And it isn’t just a problem for seeing the stars, it affects our energy consumption (which connects to a whole host of other problems), it can injure wildlife and possibly impact health. By participating in this study, you are shining the light of awareness on this problem – and that doesn’t create more light pollution!

Check it out, and comment if you like.  We always love to hear from you.

Annie Jump Cannon   Leave a comment

As you may know, International Women’s day is March 8th and today I am writing about one of my favorite early female astronomers, Annie Jump Cannon.  Born in 1863, She became deaf as a child and received a physics degree in 1884. She had a difficult time getting telescope time, as you might imagine!  She was able to find work on 1894 as a teacher’s assistant at Wellesley, and was able to learn about photography and, more importantly, spectroscopy there. In 1896, she was hired by Edward Pickering to assist with a star catalogue. Here’s where the going gets good.

She took two, partial incomplete competing systems and created a third stellar classification system – the one we still use today, more than 100 years later.  She backed up her observations with complete spectra for more than 230,000 stars – more than any astronomer, male or female, before or since. Her listing of stars in the order of O, B, A, F, G, K, M has inspired interesting mnemonics for millions of astronomy students.  Her career lasted for over four decades, during which women astronomers gained more ground. Below is a partial list of her accomplishments from Wikipedia.  Truly an amazing life!

Awards and honors

Jupiter, Venus and the Moon   Leave a comment

I hope you all have been enjoying the beautiful show in the sky the last few days. For those who don’t know, shortly after sunset you will see what appears to be two bright stars.  The lower, brighter one is Venus and the upper one is Jupiter. (I’m sure you can pick out the Moon.) Besides a lovely vista, why is this special?

The planets, unlike the stars, move ever so slightly from night to night. (Well, the stars move, too, but it isn’t visible with your eyes from Earth.) The word planet actually comes from the Greek word for “wanderer”.  The planets can appear to wander from our vantage point  as they move in their orbits and the Earth goes around the Sun.

So while the planetary motion is nothing supernatural, the view is out of this world!

This image is from Enjoy. Image

Posted 28 February, 2012 by tjsummer in Uncategorized

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