Venus Transit Report

7:17 PM, transit underway, sun going behind the trees.

The transit of Venus early Tuesday evening was the eighth such event since the invention of the telescope. The first in 1631 was predicted, but so far as we know, not successfully viewed by anyone. In 1639 two people saw the black ball of the planet Venus glide slowly across the face of the brilliant sun. About a hundred saw the transits of 1761 and 1769, by which time efforts were being made to time the event and thus determine the scale of the solar system. In 1874 and 1882, when thousands viewed, the United States spent over $300,000 dollars (not adjusting for inflation) on expeditions to time the transit. Though the scale of the solar system has long been fixed by other means, millions saw the transits of 2004 and 2012 live, at least if you count second-hand viewing by means of media. (Sources: Guy Ottewell’s Astronomical Calendar for the  numbers of viewers and a lecture by Laurence Marschall for the expenditure.)

Not looking good.

Here at Gettysburg College, about 150 fortunate souls got to see a transit of Venus first hand. For those who organized the event (Jackie Milingo, Dick Cooper, Mike Hayden, and me), disappointing memories of 2004 were fresh. The transit of that year was a morning happening, already in progress at sunrise. A thick fog hung over Gettysburg, and before it burned off, the transit had ended. No one there saw a thing. The transit this Tuesday occurred at the opposite end of the day, beginning just after 6:00 PM and still not halfway over at the time of local sunset. To narrow our chances a bit further, there is a wooded hill to the west of the observatory, and we knew the sun would dip behind those trees well before the official time of sunset. Clouds dogged us through the day. As the staff arrived to set up, the skies turned mostly sunny, only to be followed by a band of thick clouds that closed in around 5:30, just as dozens were arriving at the observatory. Their time on this pale blue dot would be up before the transits of 2117 and 2125, but the only remedy was to put a NASA webcast on a laptop and hope that it would not turn out to be their only view of the event.

Watching the webcast.

As the transit began, the webcast (difficult to see outdoors and frequently buffering) was all we saw. We noticed nothing on the image at first contact, but after several minutes, we could see a tiny dent in the edge of the sun. By 6:30 the whole of the planet Venus was enclosed by the backdrop of the sun, but still only on the webcast. All those outside the observatory were watching a blue patch of sky in the northwest moving excruciatingly slowly toward the sun, and hoping it would get there before the sun went behind the trees. There was no denying that the crowd was getting a bit tense.

“We’ve got Venus!”
Lines at the scopes.

The wait did pay off. The clouds pulled away from the sun, partially at first. We tweeted “#VenusTransit success @gettysburg!” from @GCPlanetarium at 6:37 when the faculty members supervising the solar-filter equipped scopes got their first glimpses of the sun with the transit in progress. Lines formed behind every active viewing station, but it soon became clear that that sun would remain in the big patch of blue sky until it set, and there would be no hurry. At the peak of activity, people went from view to view, looking in eyepieces or at projections, holding small children up to do the same, and snapping pictures with cameras and cell phones. I took the last picture from the observing platform at 7:17 through the eyepiece of a telescope (see top of post). It shows the sun, partly covered by unfocused leaves, but the spot that is Venus is still visible above them. Then the crowd almost all drifted away and a we started to pack up. A handful of new people walked up, local listeners of WZBT, the college radio station that had promoted the event. I was about tcommiserate with their bad timing when I took a moment to look around and realize the obvious: the athletic practice fields just to our east were still bathed in sunlight. I picked up one of the cased-up Sunspotters and we walked into the sunlit field for their only view, and my last one, of planet Venus against the sun.

Astroscan (red) and projection box.


Cooper with successful video setup.

If you are wondering about the technical side of things. here is what we had set up – all comericially available equipment, some of it quite old. Three 8-inch Schmidt-Cassegrain telescopes (one Celestron and two Meades) with standard solar filters; one Celestron 5 with video eyepiece and monitor; one Edmund Astroscan projecting into a cardboard box (the box shields the faint image); and two Sunspotters, purpose-made solar projection telescopes. As we put it all away, Mike Hayden joked that we should carefully label everything for use in 2117.

7:32 PM, a final look.



Transit Day Update

The day of the transit has arrived! If you are planning to attend the Gettysburg College Observatory event this evening, please read our original post with all the details. We look forawd to seeing you at the observatory!

A check of available weather forecasts this morning shows that conditions will not be ideal: partly cloudy with a chance of a shower or thundershower rolling through at transit time. As things stand, we are planning to go ahead with the event. It only takes a brief appearance of the sun during the transit to make it a success. But please be forewarned that we could get unlucky. If clouds hide the sun from 6:04 PM until it goes behind the trees (about 7:15), we will not see the transit.

In the case you are not able to view the transit live, here is a list of live Venus transit webcasts. We also plan to live-tweet about our local event at @GCPlanetarium.

Alumni Open House

Some photos from our Alumni College open house at the observatory on May 28.

Cooper setting up.

Looking north.
Looking east, includes the shuttle van, and someone with a red headlamp walking by.
Looking west. Mars is on the left, about 1/3 of the frame from the top.
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Transit of Venus: Public Observing

[Please also read our Transit Day Update!]

The Gettysburg College Observatory will be hosting a public observing event for the historic transit of Venus, weather permitting, on June 5 from 5:45 PM until the sun sun goes below the trees, about 7:30. Your hosts will include Dr. Jackie Milingo, astronomy professor; Dick Cooper, astronomy lab instructor; Mike Hayden, college network director and amateur astronomer; and me, Ian Clarke, planetarium director and astronomy lab instructor. We plan to set up a variety of equipment to safely observe this rare event (last until 2117). Here are the key details:

WHAT: Public Observing of the Transit of Venus.
The www.transitofvenus.org website and this video will get you started in understanding planetary transits of the sun.

WHEN: June 5, 2012, 5:45 PM to sunset.
The event will be held weather permitting. If it looks like there will be a chance of viewing the sun, we will be there to at least try. In the event of overcast skies with no breaks showing in satellite photos, we will not hold it. You may check this site or @GCPlanetarium twitter for an update the afternoon of the transit.

WHERE: Concrete pad outside the Gettysburg College Observatory.

The Observatory is located near the West Fields on the edge of campus. To get to the there, walk (do not drive) down the gravel road past the West Building (home of The Attic) toward the domed building. Only observatory staff are permitted to park at the observatory itself, so please allow time to park on campus and walk. If you cannot walk the distance but would still like to attend, email Ian Clarke ahead of time to make arrangements.There are no restrooms at the observatory, though there is usually a portable around the nearby athletic fields. This map, adapted from the campus map, shows the location of the observatory:

Finally, here is what the sky should look like from the observing platform at the start of the transit, just after 6:00 PM:

created with stellarium 0.11.1

The Sky this Month: March

Our monthly skyshows are coming up in a few days! (Sunday, 3/4, at 4 PM and Monday, 3/5, at noon). Subjects will include the opposition of Mars, the conjunction of Jupiter and Venus, the vernal equinox, a constellation tour, and astronomy news. Hope to see you at the Hatter Planetarium!

Venus, Jupiter, and the Moon Feb 22-26

Here’s a look at the local evening sky over the next few days, as the waxing crescent moon emerges from the sunset glow and passes Venus and then Jupiter. At just about 24 hours “old” tonight, the moon will be the thinnest of crescents less than 10 degrees above the horizon. Good conditions are a must for seeing the moon this soon after new. The crescent will grow and become easy to see over the next few days as the moon orbits the earth and proceeds through its usual phase cycle. It will be near Venus on the 25th and near Jupiter on the 26th. The moon’s track is shown in the images below (moon size exaggerated for clarity). The images were created with Stellarium and combined with the GIMP.

Venus and Jupiter themselves will be only three degrees apart in early March. Hear more about that at our Sky this Month Show for March, 3/1 at 4:00 PM and 3/2 at 12 Noon.

Feb 22-24, 6:00 PM.
Feb 24-26, 7:00 PM.

Observing Report: Thurs, Feb 9

Jupiter and Venus (below) above the GC Observatory dome.

 Thursday lab had a good session at the observatory, if a bit cold (28 F at the end of the second session). Both the 7 and 8 PM groups had a sky tour, including celestial sphere concepts, Jupiter and Venus in the west, and bright stars and major constellations of the season (Ursa Major, Orion and the Winter Oval, Pegasus and more). We used Meade telescopes to observe Venus, Uranus (less than one degree away!), the Orion Nebula, star clusters M37 and M35, and the Andromeda Galaxy. Before the 8 PM session was over, Mars and the waning gibbous moon were rising in the east. Both session finished with a tour of the observatory (CCD carts, research telescope, control room). We’re looking forward to going out again later in the semester and hopefully using the CCD cameras to take some telescopic images. All images here by Ian Clarke with a Panasonic FZ-100.

From lower L to upper R: Orion, the Hyades, and the Pleiades.
Uranus (L) and Venus.

Mars and the moon.

Sky this Month Shows Coming Up

Our February “This Sky this Month” show will be offered this Sunday, Feb. 12, at 4:00 PM and Monday, Feb. 13 at 12:00 Noon. Topics will include the stars and constellations of late winter, the approach of Jupiter and Venus in the evening sky, as well as current astronomy news. Shows are free and open to the public as always. Directions, etc., are available on the web site.