Venus Transit June 8

[Guest guest]

Dear List: Some information on the Venus-Sun combustion June

8.—Janna

 

http://science.nasa.gov/headlines/y2004/02jun_viewersguide.htm

 

Schedule of Events: 2004 Transit of Venus

Event Description

UT

EDT

CDT

First Contact The disk of Venus first "touches" the limb of the Sun,

and the

transit begins.

0513

1:13 am

12:12 am

Second Contact Venus' black disk is now completely onto the Sun.

0533

1:33 am

12:33 am

mid-Transit The midpoint of the 6 hour transit.

0820

4:20 am

3:20 am

Third Contact Venus begins its exit from the Sun. Look for the black

drop

effect just before Third Contact.

1107

7:07 am

6:07 am

Fourth Contact The transit is finished.

1126

7:26 am

6:26 am

 

June 2, 2004: Want to see the 2004 Transit of Venus? Be prepared to

wake

up early.

 

On Tuesday morning, June 8th, for the first time since 1882, Venus

will pass

directly between Earth and the Sun. For six hours the planet's black

silhouette

will crawl across the face of our star. It might be a pretty sight,

or not. No one

can say for sure because no one alive today has seen a transit of

Venus.

 

If you live near the east coast of North America, you can see the

crossing. The

transit will be underway at dawn and visible for as much as two hours

after

sunrise.

 

Before you read the rest of this story, a reminder: Never look at the

Sun

without eye protection. The early morning Sun rising through the

mist,

reddened and dimmed by distant clouds, is so tempting; it seems safe

to

stare. Don't! Even a low-hanging Sun can cause eye damage. Proper

transit-

watching techniques are discussed below.

 

The transit begins at 1:13 a.m. EDT (in the middle of the night) and

ends at

7:26 a.m. EDT. If you can see the Sun before 7:26 a.m. EDT, then you

can see

the transit. Sky watchers east of the Mississippi River are favored.

The transit

will not be visible at all from Mexico, British Columbia and the

following US

states: Arizona, California, Colorado, Idaho, Nevada, New Mexico,

Montana,

Oregon, Texas, Utah, Washington, Wyoming.

 

A transit of Venus isn't like a solar eclipse. The Sun won't be

blotted out or

even noticeably dimmed. Venus is too small; the disk of the planet

covers only

0.1% of the Sun.

 

Although Venus is tiny, you can probably see it without

magnification. Try

looking through a safe solar filter, for example, #13 or #14 welder's

glass or

special "eclipse glasses" designed for solar viewing. (Do NOT use

stacked

sunglasses, metallized candy wrappers or compact disks; these are

unsafe

filters often recommended in error.) Seen through a good filter, the

Sun looks

like a glowing disk, about the size of the Moon, marked with a black

speck--

Venus.

 

In the yellow zones, sky watchers can see, at most, Venus taking a

tiny bite

out of the sun's limb. In Alaska the transit begins at sunset on June

7th. Also

available: A world map and a more detailed US visibility map.

 

The view is much better through a telescope. But beware: sunlight

focused

through a telescope can blind you instantly. There are two ways to to

safely

observe using a telescope:

 

Solar projection is one way. Align your telescope with the Sun. Do

not look

through the telescope or its finder scope; use shadows on the ground

to effect

the alignment. The shadow of a telescope looks skinniest when it is

pointing

directly at the Sun. Once the Sun is in the field of view, an image

will shoot out

of the eyepiece. Hold a white screen behind your 'scope and, voila: a

picture

of the Sun. Adjust the focus of the telescope (or the distance

between the

eyepiece and the screen) until Venus looks crisp and round.

 

Solar filters are another way. Capping your telescope with a suitable

sun-filter

can reduce the intensity of sunlight to safe levels. Then you can

look right

through the eyepiece. If you're not sure what filter is safe, contact

the vendor

of your telescope to ask for advice. Or click here for suggestions.