Abstract

Joliet Junior College, a community college in Joliet, Illinois, held a free public viewing event to celebrate the April 8, 2024, Total Solar Eclipse. From Joliet, Illinois, this eclipse was a deep partial solar eclipse, not a total solar eclipse. The Moon occluded 94.2% of the Sun’s disk at maximum eclipse. About 1300 people attended this event, and each received a free custom eclipse viewer to safely see the eclipse. There were also telescopes available for attendees to safely observe the Sun. A LightSound device was available for the low vision community and NASA’s live stream of the total solar eclipse played indoors. Attendees could explore Sky and Telescope’s solar eclipse globe. The sky was clear throughout the eclipse. For several minutes around maximum eclipse, the air temperature was noticeably lower, and the sky a darker blue than when the Moon covered less of the Sun. Venus was seen by some attendees for about three minutes after maximum eclipse. In this article, I describe this highly successful event and briefly discuss the efforts involved organizing it. I also include recommendations that could help others organize similar solar eclipse viewing events successfully in the future.

1. Introduction

Joliet Junior College (JJC), a community college in Joliet, Illinois, held a highly successful free public viewing event to celebrate the April 8, 2024, Total Solar Eclipse at the college’s Main Campus. This eclipse was total in a 120-mile-wide path that stretched from western Mexico, through northern Mexico, the south-central US, the mid-western US, the northeastern US and eastern Canada (Espenak & Anderson, 2024). From Joliet, this eclipse was partial. The Sun’s disk was 94.2% covered by the Moon at maximum eclipse (U.S. Naval Observatory, n.d.-a). The Sun was visible as a thin crescent at maximum eclipse, as shown in Figure 12.

Around 1300 people attended this event. Each attendee was given a free custom JJC eclipse viewer to safely see the Sun. In addition, attendees could engage with the eclipse via a variety of telescopes and pinhole projection. A LightSound device (Davies et al., 2024) and NASA’s “Getting a Feel for Eclipses” tactile book were available for the low vision community. Sky and Telescope’s solar eclipse globe was available for attendees to explore paths of totality for eclipses occurring from 2001 to 2100.

Clear skies made the viewing experience especially memorable because we were able to experience the drop in air temperature as well as the darkening of the sky around maximum eclipse. Some of us even saw Venus for a few minutes after maximum eclipse.

This article is laid out as follows: In Section 2, I describe the preparations and planning that went into organizing the event very briefly. This is because the preparations were similar to those of the college’s October 14, 2023, solar eclipse viewing event, and they were described in detail in Dcruz (2024). Section 3 contains a description of the event itself. In Section 4, I provide tips for organizing such events successfully for the benefit of others. Section 5 contains the conclusions.

2. Organizing the Public Viewing Event for the April 8, 2024, Solar Eclipse

Solar eclipses occur infrequently yet they are easy to observe safely with eclipse viewers or eclipse glasses. Many people can view partial solar eclipses because they occur over a wide geographic area and people can see them from wherever they are located, weather permitting. On the other hand, not as many people can witness total and annular solar eclipses because the path of totality or annularity is around 100 miles wide, the path may not cover many populated areas, and not everyone can travel to be within the path. Hence, to engage as many people as possible with total and annular solar eclipses, it is important to organize viewing of the partial solar eclipse for those who are outside the path of totality or annularity, in addition to organizing viewing within the path of totality or annularity.

JJC was not in the path of annularity of the October 14, 2023, solar eclipse or the path of totality of the April 8, 2024, solar eclipse, but was fortunate to experience both eclipses as partial ones. As an astronomer who teaches “Descriptive Astronomy” and “Life in the Universe” courses at JJC, I was eager to engage as many people as possible with these two partial solar eclipses. Hence, I led the organization of public events for both eclipses. This involved working with an enthusiastic and dedicated team of people from across the college who helped in preparing for the event in the months, weeks and days before it occurred. The core members of the team were Andrew Morrison (Professor of Physics and Astronomy), Caitlin Lee (Trackman Planetarium Outreach Coordinator), Geoffrey White (Physics and Chemistry Lab Supervisor) and me (Professor of Astronomy). Several faculty members, staff and students as well as the core team volunteered on the day of the event.

Most of the steps involved in organizing this event were the same as those used in preparing for the October 14, 2023, solar eclipse viewing event and are described in Dcruz (2024). Unfortunately, the October 14, 2023, eclipse could not be seen from Joliet due to thick clouds and occasional rain. We were very disappointed that we could not witness it. We would have seen the Moon cover 44.3% of the Sun at maximum eclipse had it been clear (U.S. Naval Observatory, n.d.-a). We still held our event as we had announced that we would be indoors, in the college’s Event Center, watching the NASA live stream of the annular solar eclipse in case of inclement weather. We added a short show on eclipses and the Sun in the college’s Herbert Trackman planetarium to enrich the attendee experience. (The Trackman planetarium features a Digitarium Lambda from Digitalis Education Systems, Inc., in a 30-foot diameter dome.) Around 80 people came to the event. Each person was given a free JJC eclipse viewer in addition to being offered the NASA live stream and planetarium show. Attendees appreciated the planetarium show immensely. A detailed description of how we coped with the inclement weather is in Dcruz (2024).

Though most preparations for the April 8, 2024, eclipse were the same as those of the October 14, 2023, eclipse, there were some differences, and these are listed below:

1. For our custom eclipse viewers, we chose to have one design to cover both eclipse events. The viewers were ordered in July 2023 for both events to keep the cost per viewer low. Having to order viewers only once meant that one less task needed to be done to prepare for the April 8, 2024.

2. The NASA live stream of the total solar eclipse was shown in the college’s Main Campus cafeteria in addition to the Event Center (which was right next to where the event was held). JJC’s Media Services ran the live stream at both locations.

3. Faculty, students and staff who volunteered on the day of the eclipse were given a copy of Sky and Telescope’s guide titled “The Great 2024 Eclipse,” a few days before the eclipse (Tyson, 2024). This comprehensive guide to the April 8, 2024, eclipse helped volunteers to be suitably prepared to answer eclipse-related questions during the event.

4. Morrison and I took photographs of the Sun using a solar filter on our smartphones with the help of the Solar Snap Eclipse app.

There were volunteers who helped out at both eclipse viewing events, and they were extremely thrilled to see the April 8, 2024, eclipse. They enthusiastically carried out their assigned tasks both times but obviously were much more excited to help out at the April eclipse.

3. Viewing the April 8, 2024, Solar Eclipse from Joliet Junior College

JJC’s viewing event was held from 12:30pm till 2:30pm on the grass outside the Event Center, at the college’s Main Campus. The eclipse started at 12:50pm and ended at 3:21pm for Joliet, IL. Maximum eclipse occurred at 2:06pm. From past experience, we anticipated that most attendees would depart soon after maximum eclipse. This is why our event was set to end soon after maximum eclipse. However, we were prepared to stay till the eclipse ended if any attendees expressed an interest in doing so.

Around 1300 people attended the event, and they were each given a free custom JJC eclipse viewer to safely see the Sun (see Figure 1, Figure 2, and Figure 3).

Three Sunspotter telescopes (see Figure 3) and a Sun Funnel on an 8-inch reflecting telescope (see Figure 4) were available for attendees to view the Sun’s projected image. Projected images produced by these telescopes can be seen in Figure 4, Figure 7, Figure 11, and Figure 12.

A 4-inch Meade reflecting telescope equipped with a solar filter (see Figure 3 and Figure 5) and a Coronado SolarMax60 with a permanently mounted hydrogen-alpha filter (see Figure 6) were set up for attendees to directly view magnified images of the Sun. The Coronado telescope showed emission from the Sun’s chromosphere (the middle layer of the Sun’s atmosphere), while the other telescopes and the eclipse viewers showed emission from the Sun’s photosphere, the lowest layer of the Sun’s atmosphere (the uppermost layer of the Sun’s atmosphere is the corona). Sunspots, solar prominences, filaments and plages could be seen through the Coronado telescope, while only sunspots could be seen using the other telescopes. Figure 7 shows two sunspots visible in a projected image of the Sun produced by a Sunspotter telescope.

Pinhole projection of the Sun’s image was also available, though it was not used much as the other solar viewing methods were much more popular (see Figure 8 and Figure 9).

A LightSound device connected to a battery-powered external speaker was set up for the low-vision community. This device converts the changing intensity of sunlight during a solar eclipse to different musical tones so people with low vision can experience the eclipse via sound. None of the attendees at JJC’s event needed the LightSound device, but we plan to set it up at future solar eclipse events in case there are attendees who could benefit from it.

NASA’s “Getting a Feel for Eclipses” tactile book was also available for the low vision community to learn about solar eclipses, the paths of totality of the August 21, 2017, and April 8, 2024, Total Solar Eclipses, and the path of annularity of the October 14, 2023, Annular Solar Eclipse.

In addition, we had a solar eclipse globe from Sky and Telescope for attendees to explore (Figure 3 and Figure 10). This globe shows the paths of totality for eclipses occurring from 2001 to 2100. Many people enjoyed examining the paths of totality depicted on this globe.

Figure 11 shows the Sun in projection three minutes before maximum eclipse, and Figure 12 shows the Sun in projection at maximum eclipse.

Around 30 minutes before maximum eclipse, the air temperature began to drop noticeably and continued to drop till maximum eclipse occurred. After maximum eclipse, the air temperature started to increase noticeably for about 30 minutes. In addition, around 12-15 minutes before maximum eclipse the sky started to darken perceptibly. It remained blue but became darker closer to maximum eclipse. The opposite occurred for about 12-15 minutes after maximum eclipse.

I spotted the planet, Venus, with the naked eye, without using my eclipse viewer, about a couple minutes after maximum eclipse and told others how to find it. Quite a few people were able to see it for the next three minutes or so.

I had previously led the organization of a hugely successful public viewing event at JJC for the August 21, 2017, Total Solar Eclipse (Dcruz, 2019). Around 1500 people attended this event. The Moon covered 88.4% of the Sun at maximum eclipse then (U.S. Naval Observatory, n.d.-b), which is a little less than on April 8, 2024. There were clouds in the sky for the first half of the eclipse, and considerable haze for the rest of it. During the first half, from time to time, the clouds would thin, permitting us to see the eclipse in spurts. We were extremely happy when the clouds happened to thin sufficiently at maximum eclipse. It is likely we would have experienced a slight drop in temperature and a bit of darkening of the sky around maximum eclipse in 2017 given how deep this partial solar eclipse was (see for example, Carlisle, Dubé & Inglessis, 2024, though planet visibility in this reference is for the April 8, 2024, eclipse, not the August 21, 2017, eclipse), but the cloudy and hazy conditions prevented these phenomena from occurring.

Those of us who were at both the 2017 and the 2024 events were delighted to experience the drop in air temperature and the darkening of the sky around maximum eclipse during the 2024 solar eclipse. It was the first time I experienced both during a solar eclipse. I was awestruck that I could experience this part of the April 8, 2024, solar eclipse not just by looking at it directly with my eclipse viewer, but by feeling the cooler temperatures on my skin, by seeing darker blue skies away from the Sun and experiencing the decrease in intensity of sunlight all around me while the Sun was high in the sky. The latter was disorienting as the Sun is usually near the horizon when the intensity of sunlight is lower.

4. Tips for planning successful solar eclipse observing for the community

Given the success of the public viewing events that Joliet Junior College organized for the August 21, 2017, and April 8, 2024, solar eclipses, I list below some key tips that could help organizers plan similar successful events in the future. A more detailed list of tips is available in Dcruz (2024). I am happy to be contacted at [email protected] with any questions associated with planning such events.

• If possible, hold a free public event and give attendees free eclipse viewers or eclipse glasses.

• Choose a suitable grassy location from which the entire eclipse can be viewed. A location that also has easy access to bathrooms and an indoor space to show the live stream of the eclipse from NASA or other organizations would be ideal. The live stream can serve as a backup in case of inclement weather. The indoor space can be used by attendees to warm up if it is cold outside or to cool down if it is hot outside.

• Start planning early, especially if you plan to give out custom eclipse viewers or eclipse glasses as it can take a few months to design and order these items. Even for non-custom eclipse viewers or glasses, it is better to order them well ahead of time. Many others will be ordering these items too, and the companies making these will be swamped with orders in the weeks before the eclipse occurs and may have difficulty keeping up with the increase in demand for eclipse viewers and glasses in the lead up to the eclipse. Early planning also allows those involved at different stages of the planning process to have sufficient time to work on their tasks.

• Recruit lots of volunteers to distribute eclipse viewers or glasses.

• Train some volunteers to use any solar equipment you may have. Some attendees may not feel comfortable looking at the Sun through an eclipse viewer or eclipse glasses, so having a Sunspotter or a Sun Funnel on a telescope to project the Sun’s image would be appreciated by these people. Train at least one volunteer to use a LightSound device connected to an external speaker, in case you wish to use this device during your event. Have trained volunteers monitor all solar equipment at all times.

• Start promoting your event at least a month in advance.

• Take lots of pictures of your event and/or have a photographer take pictures.

• Have fun working with your team as you plan your event and enjoy observing the eclipse along with those who come to your event.

5. Conclusions

Joliet Junior College’s free public viewing event for the April 8, 2024, solar eclipse was a huge success as around 1300 people came to the event to view the eclipse safely. Each attendee received a free custom eclipse viewer. Several attendees looked at projected images of the Sun produced by Sunspotter telescopes and a Sun Funnel on an 8-inch reflector. Many attendees viewed magnified images of the Sun through a 4-inch reflector fitted with a solar filter and a Coronado SolarMax60 telescope. There was considerable interest in the solar eclipse globe. A LightSound device and NASA’s “Getting a Feel for Eclipses” tactile book were available for the low-vision community to engage with the eclipse.

Attendees experienced the drop in air temperature and the darkening of the skies that occurred for several minutes around maximum eclipse due to how deep this partial solar eclipse was and because the skies were clear. Some attendees saw Venus for about three minutes after maximum eclipse. Because of these experiences, this eclipse was indeed a memorable astronomical event.

Many attendees mentioned that they enjoyed the college’s event immensely. One long-serving JJC employee said that it was the best event she had ever attended at the college. These remarks are extremely gratifying and are greatly appreciated.

Many faculty, students and staff contributed to the success of this event by helping to prepare for it and volunteering at the event itself. Their contributions were invaluable.

It was fortunate that the weather conditions were extremely favorable for this eclipse, resulting in so many people viewing it easily. The next time Joliet will experience as a deep partial solar eclipse as this one will be on September 14, 2099, which is a long way off.

Due to the success of this event and JJC’s August 21, 2017, solar eclipse viewing event, I have provided tips on how to organize successful solar eclipse viewing events for the public in this article. I hope these will be beneficial to those who are planning such events in the future.

Acknowledgements

I am very grateful to the Joliet Junior College Foundation and the Joliet Junior College Department of Natural Sciences for providing funding for the October 14, 2023, and April 8, 2024, solar eclipse viewing events. I also thank the editors for providing feedback that helped to improve this article.