Coming up! “Two Small Pieces of Glass”

Sunday, October 15, at 2:30 and 4:00
Thursday, October 19, at 12:00 Noon

“Two Small Pieces of Glass: The Amazing Telescope” is a full-dome video show that “follows two students as they . . .learn the history of the telescope” and explore “the wonder and discovery made by astronomers throughout the last 400 years.” BONUS:  our own livedemonstration on the current sky. Total time <40 minutes.

The show is free and all are welcome. Doors close when the show begins.

Upcoming Show: The Sky this Month

Sunday, October 1, 2:30 and 4:00
Thursday, October 5, at 12:00 Noon

Faculty and staff take note: We’ve brought back our weekday noon showing. No food and drinlk in the planetarium, but you should be out by about 12:40.

Visit our immersive, full-dome digital theater for a guided tour of the current night sky and a review of recent astronomy news. This month’s edition will include the astronomical roots of Halloween. This free program is a live presentation given by Hatter Planetarium director, Ian Clarke. The full fall schedule can be found here.

The Hatter Planetarium is located on the first floor of Masters Hall. The show is free and the public is welcome. First-come, first-seated; the doors close when the show begins.

Coming Up: “Constellations across the Cultures”

Written and produced by Hatter Planetarium students and staff, with insights from Gettysburg College faculty, this is our own full-dome show created in Spring 2017.
Sunday, September 17, at 2:30 and 4:00
Thursday, September 21, at 12 Noon.
You might look into the night sky and see a hunter, a bear, or a harp. But what about a drinking gourd, fish trap, or meat ant?  We’ll use the full-dome, immersive environment of the planetarium to explore what constellations are, the history of our familiar set, and how the same groups of stars have been imagined by different cultures at different times. Running time about 40 minutes, including a bonus live sky tour.
The Hatter Planetarium is located on the first floor of Masters Hall. The show is free and the public is welcome. First-come, first-seated; the doors close when the show begins.

Field Trip Request Form is Open for 2017-18

A local elementary school group.

We are now taking field trip requests from school and community groups for the 2017-18 academic year. Just complete this form on our web site. If you are a teacher or group leader, here are few things to keep in mind when thinking about shows for the 2017-18 academic year:

  • Our shows are all free!
  • Reserve as early as you can; demand gets heavier after the Christmas break, and our “season” ends in early May.
  • Our window for doing shows during weekday school hours will once again be Thursdays. Evenings and weekends are somewhat more flexible, depending on other demands on the space.
  • The capacity of the theater is 40 in seats or ~80 on the floor.
  • Outreach is an important mission of Gettysburg College’s planetarium, but it is not the primary one. Please be aware that you’re entering a working college environment, probably with classes in session in the building, and also that none of the staff works full-time on the planetarium
  • It’s AMAZING!

Fall 2017 Schedule of Shows

Announcing our fall schedule of public planetarium shows! All are free and open to the public in our immersive, digital planetarium theater in Masters Hall on the Gettysburg College campus. We’ll start with “The Sky this Month” on September 4. In addition to a look at what’s up in September, this show will include a segment on Gettysburgians’ experience of the 2017 solar eclipse, from campus to the path of totality.

We are bringing back a weekday noon show, now on select Thursdays, to give college employees more of a chance to visit our renovated planetarium (though these show are open to the public too). While you can’t eat in the planetarium, our show length of about 40 minutes should give you time to get a quick bite afterward.

In addition to the posting below, the schedule is available as a PDF, and all public shows are published on the college’s events calendar.

See you at the planetarium!

Hatter Planetarium Schedule
Fall 2017

The Sky this Month

  • September 3, 2:30
  • September 3, 4:00
  • September 7, Noon


Constellations across the Cultures

  • September 17, 2:30
  • September 17, 4:00
  • September 21, Noon


The Sky this Month

  • October 1, 2:30
  • October 1, 4:00
  • October 5, Noon


Two Small Pieces of Glass

  • October 15, 2:30
  • October 15, 4:00
  • October 19, Noon


The Sky this Month

  • November 5, 2:30
  • November 5, 4:00
  • November 9, Noon


The Hot and Energetic Universe

  • November 12, 2:30
  • November 12, 4:00
  • November 16, Noon


The Sky this Month

  • December 3, 2:30
  • December 3, 4:00
  • December 7, Noon


Pennsylvania Eclipse in the 30s?

Was there a solar eclipse that a south-central Pennsylvania school child might have seen around 1935? First, my apologies to the gentleman who asked this question at our pre-eclipse show on August 13. He remembers smoking glass in prepartion for viewing the event. [Don’t do this, kids! Keep your quality-controlled, ISO-certified solar glasses.] Anyway, I intended to post an answer that week, but before I could research, NASA redirected all its web eclipse traffic to their “eclipse 2017” site. But now the information is back. Here is the map of North American total eclipses of the sun from 1901-1950.

So there was no total eclipse in south-central PA through the whole period. The famous New York total eclipse of 1925 would have been partial here, but surely too early for our audience member’s recollection. For further data we can turn to NASA’s online JAVASCRIPT SOLAR ECLIPSE EXPLORER.  It’s fun! And it reveals three or four candidates. The August 31, 1932 eclipse (path of totality on the map above) would have been 88% partial here, so that is a possibility. Next chronologically is a partial eclipse on February 3, 1935. With 31% obscuration it’s worth observing and it’s the year our guest remembered. On April 19, 1939 locals would have seen an 8% obscured sun. I am not sure that would have been worth getting school kids exicted about. Finally April 7, 1940 brought an annular eclipse to some parts of the country. It would have been 61% partial in south central Pennsylvania.

I hope this helps, sir!


New Seating Option

Avarte Funktus Auditorium Chair

There are Funktus amongst us! Beginning with the eclipse shows on August 13 and 14, there will be a new seating option at the Hatter Planetarium. Ten of these Avarte Funktus auditorium chairs were part of the original plan for the summer 2016 renovation, but tracking them down and acquiring them proved a bit of a challenge. They arrived this week, and you’ll find them in the back row at public shows. Feel free to sit there if you prefer a more traditional seat than our rolling classroom seats. When the planetarium is in classroom mode, the new seats can be stored out of sight.

The Eclipse of 2017: A Local Perspective

Something big is happening in the sky on August 21. For the first time since 1979, a total solar eclipse will be visible from the contiguous US. Though Gettysburg will see only a partial eclipse, it is not out of the question for local sky gazers to travel to the path of totality, which occurs in a 70-mile wide strip stretching from Oregon to South Carolina.

Image credit: NASA Visusalization Studio More info:

Anyone making such a trip has doubtless done a lot of research. In this post I will try to describe the event for those left behind in the Gettysburg area.

First, let’s define a few terms. A solar eclipse occurs when the moon, from the point of view of an observer on earth, covers up some or all of the sun. A lunar eclipse is when earth-based observers see the shadow of the earth covering some or all of the moon. These eclipses occur at least four times every year, sometimes more. The schedule is predictable but not regular. Thus the fact that there was a total eclipse of the sun crossing the USA from coast to coast 99 years ago does not mean that there will be another 99 years from now. The actual cycles of eclipses are both complicated and fascinating. Solar and lunar eclipses differ in their accessibility. A total lunar eclipse is visible anywhere on earth that the moon is up during the eclipse period. That’s over half the earth. In contrast a total solar eclipse can be seen only in a very limited geographic area.

One last note: while a partial eclipse is truly worth watching; it is not just a lesser version of a total one. The iconic moments of a total eclipse of the sun, such as being able to see the sun’s corona (its faintly glowing outer atmosphere) or being able to see stars in the daytime, only occur during totality. They are not visible during a partial eclipse, such as Gettysburg will experience. Even a small portion of the sun is extremely bright!

Locally the show will get under way at 1:17 PM EDT with first contact. That’s when the moon begins to “take a bite” out of the sun.

Now here’s the safety part: it is not safe to look at the sun even when it’s partially covered up. Pointing binoculars or a telescope at the sun (without knowing exactly how to prepare and equip it) can lead to instant eye damage. Get yourself some “eclipse glasses.” You could order online from a reputable source; I’ve also seen them locally at Lowes of Waynesboro. Instead of or in addition to the eclipse glasses you can make yourself a pinhole projector. It’s cheap and it works.

Back to the local schedule. From 1:17 on the moon will cover more and more of the sun, until maximum eclipse at 2:41 PM, when the 79% of the sun (by area) will be covered. The sight will look like this through your filter glasses or on your pinhole projection:

Maximum eclipse from Gettysburg


Notice how the moon and sun are about the same size. “But wait!” you say, “isn’t the sun a lot bigger than the moon?” Yes, about 400 times bigger; the moon happens to be about 400 times closer.

After 2:41 the moon’s disk will slowly slide by and the area of the sun visible will increase. With last contact at 3:59, the partial eclipse will be over.

How will weather affect viewing? In order to actually observe the sun and moon as depicted in the image above, the sky will need to be clear enough to see the sun. If it’s overcast that won’t happen, though you may still notice some darkening of the skies around the time of maximum eclipse.

You may also be wondering about events in the environment. Will it get dark? Will birds roost? That’s a good question. 21% of the sun is still very bright, so it won’t get dark in the Gettysburg area, but you may well notice some changes around you. Some of you may remember the eclipse of May 1994. It was an annular eclipse from some parts of the US, though it was partial (83%) here in south-central PA. I was fortunate enough to see this one from Gettysburg, and near maximum eclipse the light definitely looked odd. I even saw the partially eclipsed sun projected by natural “pinholes” between tree leaves. Birds grew quiet and a breeze blew up. It was a wonderful afternoon, though it was unmistakably daylight.

Finally, you may be interested in future total eclipses of the sun in the US. We don’t have to wait as long this time. The total solar eclipse of April 8, 2024, has  a path that cuts from Texas to Maine and includes a bit of northwestern Pennsylvania. If, however, you want to view a total eclipse of the sun from your backyard in Adams County, you’ll need to find some way of living until September 12, 2444.

At Gettysburg College we have events planned before and during the eclipse. On August 13 and 14 the Hatter Planetarium will present “Eclipse Across America” to help get you ready. During the eclipse itself there will be a public event at the Gettysburg College Observatory, hosted by Dr. Jackie Milingo and Dr. Craig Foltz. Your humble scribe (Ian Clarke) plans to be somewhere in the path of totality on that day. Clear skies, folks!




Public Eclipse Viewing at the Gettysburg College Observatory

2012 Transit of Venus at Gettysburg College Observatory

The Gettysburg College Observatory will be hosting a public observing event for the August 21, 2017, eclipse of the sun, weather permitting. Your hosts are Dr. Jacquelynne Milingo and Dr. Craig Foltz. They plan to set up equipment to safely observe this event. They will have a limited number of solar filter glasses for you to use. Some local retailers (e.g., Lowes in Waynesboro) are also selling them, so you may want to bring your own.

Here are the key details for eclipse day:

WHAT: Public Observing of the August 21, 2017 eclipse of the sun. This
website will get you started in understanding this event. NOTE: the eclipse is paritial, not total, from Gettysburg. This post will give you an idea of what to expect locally.

WHEN: August 21, 1:00-4:00 PM. (Eclipse maximum is 2:41.)
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.

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. There are no restrooms at the observatory, though there is usually a portable within walking distance. This map  shows the location of the observatory:

Special Summer Show: “Eclipse Across America”

Sunday, August 13, 2:30 and 4:00 PM
Monday, August 14, 12:00 Noon
At the Hatter Planetarium

This year we are ending our summer hiatus early to help you prepare for the solar eclipse of August 21, 2017 with a viewing of “Eclipse Across America.” This show will detail the lore and mechanics of eclipses and give you a big picture view of the the way this eclipse will unfold across the contininent. We will follow the show with a live presentation on the local circumstances of the event and ways to view it. We’ll finish up with some Q & A. Note: the path of totality does not enter Pennsylvania. Weather permitting, Gettysburgians will witness a partial eclipse, with about 80% of the sun covered by the moon.

Total show time is about 40 minutes. The show is free and open to the public on a first-come, first-seated basis. Doors close when the show begins.

“Eclipse Across America” was created by Dan Zielinski of Jenks Planetarium (Oklahoma) and Dr. Todd Young of Fred G. Dale Planetarium (Nebraska) and distributed to Spitz SciDome planetariums free of charge.