Glimpse eclipse at 1:42 p.m.
A solar eclipse will create a bright golden ring in the sky this afternoon, but viewing the eclipse improperly may cause blindness.
At around noon, the moon will begin to pass between the earth and the sun, blocking out most of the sun's light.
Between 1:37:25 p.m. and 1:43:30 p.m. today, the moon will appear to be in the center of the sun's disk.
Because this is an annular eclipse and not a total solar eclipse, the moon will only cover about 90 percent of the sun.
"An annular eclipse is when the moon is farther away in its orbit and it appears smaller than the sun," said Andy Williams, secretary of the Dartmouth Stargazers. "You get a gold ring in the sky like a great big doughnut."
A total solar eclipse occurs when the moon passes in front of the sun at a point in its orbit closer to the earth, Williams said.
Williams said today's eclipse will not produce much visible difference in the sky.
"The sky will be a little darker but you won't notice it because your eye adjusts, like when a cloud goes over the sun, but this happens gradually over an hour and a half," he said.
"But if you look during the time the moon is on the sun, the sky will seem bluer, the light will be a little odd and you can see Venus if you know where to look and probably Mercury," Williams said.
But Williams strongly emphasized that no one should look directly at the eclipse because doing so could cause severe retinal damage.
"People think that because the sun is blocked by the moon, it's okay to look at the eclipse, but the sun is not entirely blocked," he said.
On a normal day, a reflexive action causes a person looking at the sun to squint. But because the sun will be partially blocked tomorrow, the eye will not sense that it should reduce the amount of light it is allowing in, Williams said.
"The sun is dimmer and your eyes will not hurt so you will think it is OK but you can VERY EASILY cause PERMANENT eye damage. I am dead serious about this. You can create a permanent blind spot in your vision. DON'T DO IT!" Williams said in a BlitzMail message distributed around campus.
During the last solar eclipse visible in New England in 1970, more than 100 cases of blindness were reported in people who viewed the eclipse without protective eyewear, according to the Associated Press.
In his book, "Eclipse," Bryan Brewer explained the danger of looking directly at an eclipse.
"The lenses of your eyes act as tiny magnifiers; if you look at the partially eclipsed sun, its rays are focused on the retina of your eyes and can burn them. This is the same sort of thing that happens when you use a magnifying glass to focus the Sun to a pinpoint on paper or leaves to burn a hole in them."
To protect against eye damage, Williams said people should view the eclipse using a telescope with a solar filter, a pin hole camera or a welding mask rated at least 14.
He said pin hole cameras are easy to make. "All you need is a piece of white paper and a piece of cardboard," Williams said. "Put a pin hole through the cardboard. A smaller hole will make a smaller, but crisper picture and a larger hole will make a larger fuzzier picture. Focus the pinhole on the paper and that's perfectly safe to look at."
Williams said the Dartmouth Stargazers will provide all three kinds of viewing equipment on the green between 11:45 a.m. and the end of the eclipse.
The National Weather Service calls for partly sunny skies today.
"Clear skies are best, but partly sunny will do fine," Williams said.