Venus transit announcement, long version, part 2

We have a solar telescope in the observatory and a white light filter for a second telescope inside HJRO. We will be open for viewing the Venus transit and have at least six FAAC astronomers there. We will have other telescopes outside. Some telescopes will be available for viewing through. If we have large crowds we will have more than one telescope and the Venus Transit will last for at least 2 hours at our site. So if the weather permits, a lot of visitors will have a chance to see the disk of Venus in front of the sun.

We will also have a "projection" system there. Not an only projection system that projects the sun behind a telescope, but a different kind of open air kind of projection system developed by Ed Jones an astronomer in Ohio. This uses a flat mirror and a special lens that allows a large disk of the sun to be projected about 88 feet away from the projector. This large disk is 9 1/2 inches in size and will be either projected on a large AV screen outside the observatory door in the shade or on a piece of poster board (if it's windy). This projects the sun in a beam but it's never concentrated into a point as that beam travels to the screen, it only spreads out from 4 inches to 9.5 inches where it's in focus. This beam is not as dangerous as the old projected beams because there is no concentrated light. But you still don't want to look at the flat mirror and the beam as it's almost as bright as looking at the sun directly.

You can see the large disk on the screen and you will see sunspots. We could also filter that beam with a filter and give it a color that would make it look yellow or orange, but I'm not sure we'll try that, because it's going to look better and sharper and brighter without a filter on it.

We will also have between four and six other telescopes setup outside, most of these will have white light filters on them. Showing sunspots and the disk of Venus passing over the sun. There may be one other HA setup outside, but I'm not sure it will be available for direct viewing, it may be used for photos being taken of the sun during the event. We may also use one of the telescopes inside the observatory to take photos from time to time. If we take photos it will be through the Meade Telescope inside the observatory and that will have a laptop connected to it, so you may see the photos as they are being taken on a laptop screen.

Outside we should have a few other viewing options. The Venus transit will start at about 6PM. If you want to see the beginning of the transit you will need to arrive early. We cannot say that everyone who visits will be able to see the exact start of the transit as there are only so many telescopes. There is an interesting timed event that is happening, that some astronomers will want to measure, it's the moment the venus shadow disk is just inside the suns disk. Some astronomers present may be taking pictures at that time (around 6:15 to 6:20) and they may be timing the transit with their iphone or android "TRANSIT OF VENUS APP". They may be taking photos through some of the telescopes. Once that moment is passed, we will see the shadow continue it's move across the disk of the sun. It will be a round dot. It will continue to travel across the sun and still be on the face of the sun as the sun sets in this area.

Now some will be viewing this for up to three hours here. If your on the rooftop of Wayne State or at the boat launch you can view it for a longer period of time. If you view it from HJRO, you will not be able to view it for 3 hours, but only for 2 hours, because the sun will start to be obscured by large trees in front of Lincoln Park High school. This will block our view of the last hour of the sun. Some positions may see the sun from our site for up to 30 minutes more. I may move the projector on the running track and we might be able to view the sun up to 8:30PM on the projection screen, but most telescopes on the grounds will be finished by 8PM. Some astronomers may even decide to drive to a nearby location with their scopes just before 8PM if the crowd is small and they decide it's worth the short trip. There is another viewing location, but it's away from the observatory and I don't think anyone is planning on going to that location. It's in Allen Park and only a few people can observe from that spot, due to limited parking.

NOW IF YOU DON'T HEED our advice to SAFELY VIEW THE SUN what will happen to your eyes.

If you do the wrong thing and want to view the sun in an unsafe manner, you will likely cause permanent damage to your eyesight, up to and possibly including permanent blindness. If you view the sun with your naked eyes within 40 to 90 seconds you will damage your eyes. You will not feel the damage and the cells in your eyes will not feel the pain. 24 to 48 hours after you damage your eyes you may not be able to recognize faces of your loved ones at the dinner table, because your eyes will be damaged. If you use a telescope or binocular to view the sun without the proper filter, you will likely cause immediate thermal damage and blindness and will never see again.

You should not look at the sun directly. If you damage you eyes with just some minor damage, your eyes may recover. You may have cataracts later in life and have to get surgery when your old, because you looked at the sun in an unsafe manner when you were young. PLEASE BE SURE TO ASK QUESTIONS OF SOMEONE WHO KNOWS WHAT THEY ARE TALKING ABOUT. Make sure you are viewing the sun through a safe viewing method.

There are eclipse sun glasses, but these are not to be used with other optical aids, like binoculars. Many filters are to be used IN THE FRONT of the telescope. There are really not filters that are to be used at the eyepiece that are safe without a filter in the front of the telescope. Some things, that new people in astronomy try, thinking it's safe, are NOT SAFE.


BAD STUFF
It's NOT SAFE TO USE WRAPPERS or SILVER BALLONS as a filter.
It's NOT SAFE to use a CD or DVD disk as a filter.
MOST WELDERS GLASSES ARE NOT SAFE.
EXPOSED FILM IS not safe.
OLD Filters used ONLY in the eyepieces are NOT SAFE

SAFE
PST or SOLAR telescope.
Safe filters made by major companies like Thousand Oaks, Baader Planetarium (The filters must be for VISUAL USE, not photographic filter rated solar filters.)
EYEPIECE projection can be safe, but you must be careful about the setup.
Pinhole projection is safe, but you're not going to probably see a large enough image to see Venus in the transit.
Eclipse glasses are safe.

And the "safe" methods need to be inspected by someone who knows if they are damaged. A safe filter can be damaged so careful handling and setup needs to be done to insure your eyes won't be harmed.


When in doubt, don't. Save your eyesight for another day. You can always watch it on the internet.


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