how to safely watch the transit of venus on tuesday - aluminized mylar film
Many people plan to watch the Golden Star Day on Tuesday (June 5)
But it is very important to remind potential viewers to take special precautions (
Like a solar eclipse.
Watch the outline of Venus on the bright sun pan.
For the United States and Canada, transit will begin when Venus's black plate first touches the outer rim of the sun, what astronomers call "contact I ".
From Eastern United States. S.
Eastern Canada, I should contact around 6: 03. m. EDT (2203 GMT).
From the western United States. S.
Western Canada, I should contact around 3: 06. m. PDT.
It takes about 18 minutes for Venus's black plate to move completely to the sun's face;
Eventually, its black plate is on the edge of the upper left corner of the sun.
If you imagine the disk of the sun as the surface of the clock, I will contact me between 11: 30 and 12.
Venus will then move along the track running diagonally from the top left to the bottom right.
If you want to predict transit time from where you live, the astronomical application department of the US Naval Observatory has produced an online transit computer at the following locations: sunling day involving mercury, the Transit of Venus is easy to see with the naked eye;
This planet as a uniquealbeit tiny —
Black spots with a diameter of only 1/32 of the sun.
This size is large enough to be easily perceived with the naked eye. [
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Eye Safety is always a major problem when dealing with the sun.
Watching the sunspots is like studying sunspots, because after all, you see a black spot on the sun.
But trying to see the sunling is also like trying to see a solar eclipse.
You have to be ready at a specific time and you may have to be far away from home.
However, for the transit of Venus, your exact location is far less important than total solar eclipse.
In particular, observers in eastern North America, where transit will occur in the evening, your observation site should have a low horizon to the eastnortheast.
Check the sunset points of the sun and verify that trees or buildings do not block your sight, which is a good precaution.
When Venus passes through the surface of the sun, it will look absolutely black compared to the gray of any sunspots that may be present on the solar disk.
The safest way to view the crossings so far is to build a so-
The so-called pinhole camera.
Small holes or small openings are used to form an image of the sun on the screen, which is located about 3 feet behind the opening. [
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Binoculars or small telescopes mounted on a tripod can also be used to project an enlarged image of the sun onto a white card.
When telescopes or telescopes point directly to the sun, be sure not to pass through them!
Venus should be an obvious small dot on the projected image.
A variant of the Pinhole theme is "pinhole mirror ".
"To make one, cover the pocket mirror with a sheet of paper with four coins --
Made an inch hole in it. Open a sun-
Facing the window, place the covered mirror on the sunny windowsill so that it can reflect a plate of light on the far wall inside.
The disc is an image of the face of the sun.
The farther away from the wall, the better you place it;
There are only 1 inch pictures per 9 feet (2. 7 meters)
From the mirror
The clay model holds the mirror well in place.
Size holes on paper.
Again, a big hole makes the image bright but blurry, and a small hole makes the image dim but clear.
To achieve the best results, darken the room as much as possible.
Be sure to try it in advance to ensure that the optical quality of the mirror is good enough to present a clean, circular image.
Of course, don't let others look at the sun in the mirror.
Acceptable filters for independent visual solar observations include aluminum-containing Mella.
Some astronomical dealers carry Mela filter material specially designed for sun observation.
Arc No. 13 or No. 14 is also acceptable
Welder glass, only a few dollars in the welding supply store.
Unacceptable filters include sunglasses, old color film negatives, neutral photos
Density Filter and polarization filter.
Although the visibility of these materials is very low
The level of light transmission, they pass the near of an unacceptable high level
Infrared radiation that can cause thermal retina burns.
The fact that the sun looks dim, or that you don't feel uncomfortable when you look at the sun through a filter does not guarantee that your eyes are safe.
Projecting an enlarged image of the sun onto a white card or screen using a telescope is relatively safe and can be used for group viewing.
For severe transit observations, a full telescope
The aperture solar filter is much better.
These filters are attached to the side of the telescope facing the sun, not the side facing your eyes.
This will cause most of the sun to be filtered out before entering the telescope. [
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Transit can only be viewed using the right solar filter --
Solar filters sold by famous astronomical equipment.
If your mirror belt has a filter fixed on the eyepiece, discard it immediately!
As we all know, these filters break at the high temperature of the Sun's enlarged image.
Finally, never look at the sun directly through your telescope or even through your viewfinder.
It is highly recommended to cover the viewfinder before shipping to avoid accidental browsing.
I was recently asked if they could look at the sun through a telescope when they were wearing a pair of "eclipse glasses"-special filters mounted on cardboard glasses frames.
The answer is definitely not!
This filter is bare. eye use only!
If you try to pass through the eyepiece of a telescope or telescope while wearing these glasses, the concentrated heat from the sun will almost certainly melt a hole through the filter material, let the dazzling sun burst into your eyes. Next Time?
If bad weather hinders or completely obscures your view of the Golden Star, the next opportunity will not arrive until December. 10, 2117.
Unfortunately, when that date finally arrives, it is unlikely that most people who are reading these words will be nearby. [
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In addition, most parts of North America will miss 2117 events, as transit will not begin until the sun sets.
Only the far West observer can see the beginning of Venus crossing the sun before sunset.
The Golden Star Day of December
However, 2125 will be more friendly to North America.
Soon after sunrise, Venus will begin to cross the sun into the East Coast.
For the rest of the continent, Venus is already on the sun when it rises.
See the last two or three hours of transit from the west coast of Canada and the West Coast of the United StatesS.
Editor's note: If you take a good photo of the Golden Star and want to share it with space.
For a story or gallery, please send pictures and comments to the space.
Tariq Malik, com executive editor of Tmalik @ space. com.
Joe Rao is a lecturer and guest lecturer at the Hayden Planetarium in New York.
He writes astronomy for The New York Times and other publications, and he is also
Camera meteorologist for News 12 Westchester, New York.