The ClassAction browser is once again available on the internet. This has been made possible by improvements to Ruffle, an emulator that supports Flash content in modern browsers.

The ClassAction project consists of over 500 think-pair-share questions for use in introductory astronomy classrooms. Many of the questions feature animations, permutations, and hints. The questions are also supported by simulations and images which can be opened in pop-up windows.

ClassAction can also be used offline as a native app, available for Windows or MacOS.

The AAS Education Series has just released a video highlighting a new simulation created by the UNL Astronomy Education Group. This simulation depicts stellar evolutionary tracks and isochrones by making use of the MESA work from Harvard astronomers.

The new simulator and other NSF-funded smartphone sims are profiled in the AAS Education Series interview of Kevin Lee on YouTube. See the playlist for other videos in the series.

The underlying pedagogy is discussed in another set of videos, the AAS Smartphones in the Astronomy Classroom Series.

The new Stellar Evolution Simulator is available on our Smartphone Simulations page. A direct link is available here.

The Physics & Astronomy Summit 2024 will be held on Saturday, October 12. Our plenary speakers this year will Christopher Orban (The Ohio State University, expert in professional development workshops in computational physics) and Adam Houston (University of Nebraska, researcher on superstorms). The format will be similar to that of past summits. Local educators interested in leading a breakout sesssion or longer session are encouraged to proactively contact Kevin Lee (klee6@unl.edu) the Summit organizer. Registration information is available on the promotional flyer.

A new simulation is available on the Smartphone Simulations page. It uses the MESA stellar evolution models to illustrate how stars of different masses evolve. The Stellar Evolution Simulator can illustrate the paths of single stars, multiple stars, or clusters with different stellar masses. One can label stars with the initial or current masss and start evolution on the ZAMS omitting the protostar stage

Several resources related to eclipses are available on the https://astro.unl.edu site. These include:

• Simulations - The Eclipse Explorer (available at https://astro.unl.edu/smartphone/EclipseExplorer/) is a suite of five html5 simulations targeted at smartphones. The Labeled Shadow Diagram is useful for visualizing the different types of eclipses, while the Eclipse Table allows one to view how often eclipses occur.
• Astronomy Demonstration Videos - This set of over 40 videos on demonstrations commonly performed in the introductory astronomy classroom is available at https://astro.unl.edu/video/demonstrationvideos/.
  • Eclipses 1: Shadows & Scale – this video (available on YouTube at https://www.youtube.com/watch?v=huVCQXYy4jc) covers the types of eclipses and how they are related to the types of shadow.
  • Eclipses 2: Eclipse Seasons – this video (available on YouTube at https://www.youtube.com/watch?v=-kw6pW46saI) covers the 6° inclination between the plane of the Moon's orbit and the plane of Earth's orbit around the Sun.
• Formative Assessment Tasks – this sequence of ranking and sorting tasks (available at https://astro.unl.edu/newRTs/Eclipses/) will test understanding of many concepts related to eclipses.

The newest version of the Interactives Editor supports Labeling Tasks. It will allow authors to start with an astronomy image or diagram, place blanks over certain locations, and then specify a pool of appropriate terms and distractors. Students are then asked to drag a term to the appropriate location. These can serve as an introduction to material leaving the higher levels of Bloom's taxonomy for ranking and sorting tasks. Early applications included labeling spectral types in a starfield and the regions in the cutaway diagram of the interior of Earth. An example on Solar System Models is available here.

A problematic issue recently arose in Ruffle which disabled the reporting of slider values in textboxes. We have reverted to the November 9, 2023 version of Ruffle for the time being to avoid this issue.

A new simulation is available on the Smartphone Simulations page. It combines previously available components of Legacy simuations — the Daylight Hours Explorer (our most popular simulation) and a simplified Sun Motions Demonstrator. It allows one to explore the length of daylight hours as a function of latitude and date while viewing the corresponding path of the Sun in the observer's horizon diagram.

Two new videos are available on the Astronomy Demonstration Video page and on the YouTube UNL Astronomy channel. These videos include:

• Gravitational Lensing– which uses a wine glass stem to mimic the gravitational bending of light from quasars and distant galaxies. It is available here on YouTube.
• Stellar Spectra– which uses a didymium filter to model the absorption of spectral lines in the outer layers of a star. It is available here on YouTube.

A flyer promoting the 2023 Ruckman public lecture at 7:30 pm on Friday, October 6, 2023 in the UNL Student Union Auditorium is available here.

A flyer promoting the 2023 Physics & Astronomy Fall Summit is available here. Registration information for local teachers and information on both plenaries is available.

We have seen substantial improvements in Ruffle's emulation of ActionScript 3.0 over the summer. Note that many legacy resources that were problematic in the past are now functional. In fact, it appears that the small number of remaining shortcomings in Ruffle's emulation of ActionScript 3.0 are comparable in severity to those in ActionScript 2.0. Note that the ActionScript 3.0 blue screen warning still appears at this time, but we will likely turn that off shortly. Additional information will be posted on this topic as it becomes available.

This affects the following simulations: Sidereal and Solar Time Simulator, Lunar Phase Quizzer, Moons Phases With Bisectors, Earth Orbit Plot, Doppler Shift Demonstrator, Galactic Redshift Simulator, Pulsar Period Simulator, Circumstellar Habitable Zone Simulator, and numerous components of the NAAP Variable Star Photometry Lab.

This year's Summit will be held on Saturday, October 7, 2023. It will be held in Jorgensen Hall on the UNL city campus and will be similar in format to last year's workshop lasting most of the day. Our plenary speakers will be Dan Reichart (Professor of Physics and Astronomy at the University of North Carolina at Chapel Hill) an expert on teaching with robotic telescopes and David Harwood (Professor and Stout Chair in Stratigraphy of the UNL Department of Earth and Atmospheric Sciences) an expert on using Antarctic ice sheets to learn about elevated global temperatures.

If you are interested in being on the program (running a booth, a 30-minute breakout session, or a 90-minute breakout session) you are encouraged to proactively contact Kevin Lee at klee6@unl.edu and make arrangements.

The event was covered by the Nebraska News Service which interviewed several members of our group. Here are some additional event pictures of our group:

Morrill Hall's monthly "Meet the Scientist" event will feature Kevin Lee, as well as department members Keith Foreman, Rebecca Udby, and Simone Hill, and other members of the UNL Astronomy Education Group Chris Siedell, Emily Weissling, Sukaina Al-Hamedi, Frannie Mace, and Clara Carper as well as several ASTR 103 Honors Students. The event will look at eclipses from a variety of perspectives including simulations and sorting tasks.

CSMCE Project Assistant Emily Weissling delivered a presentation on Saturday, February 25 entitled “The James Webb Space Telescope and Infrared Light” as part of the Physics Department’s Jaecks Saturday Science program. The annual program brings hands-on science to Lincoln 5th graders.

In the image above (click to enlarge), enthusiastically glowing 5th graders eagerly try to show up in an infrared camera image of the audience.

The Interactives Editor available at https://astro.unl.edu/newRTs now allows the creation of sorting tasks. Icons can be either images, labels, a combination of both, or mixed. Sorting tasks are useful in formative assessment for probing characteristics, membership, and values where ambiguity would prevent a ranking task from being effective.

Example Sorting Task: Consider icons of labeled graphics depicting each of the planets and asking students to sort them into two bins: one with ρ > 2.0 g/cm³ and one with ρ < 2.0 g/cm³.

A first effort can be found here and at the QR code.

Development of this additional capability in the Interactives Editor was funded by the NASA Nebraska Space Grant.

The Nebraska Physics & Astronomy Fall Summit will be held on Saturday, October 22 in Jorgensen Hall on the UNL campus. The event targets all instructors of Physics and Astronomy at the high school and college level. A flyer describing the event and how to register is availalble here. An evolving detailed schedule of the day's events is available here.

The Ruckman Public Lecture will be given by Dr Michael Lam of the Rochester Institute of Technology and is entitled "Celestial Clocks and Ripples in Spacetime". It will be given on Friday, October 21 at 7:30 pm in the Nebraska Student Union Auditorium. The presentation is open to the public and is appropriate for general audiences. A promotional flyer for the event is available here.

A number of offerings on our web site have undergone changes recently. The following detailed handout is provided to summarize these changes.

A number of Legacy Projects (NAAP, ClassAction, and the Interactives) are once again posted on this site. This is now possible due to the recent improvement of the Ruffle Flash emulator. Although Ruffle is a work in progress, it has progressed to the point where many of these files are once again useful (and we speculate that more of them will be useful shortly as development of Ruffle is ongoing). Note that Ruffle is not a plug-in and poses none of the security risks that Flash posed.

A series of videos surveying using smartphone simulations in the introductory classroom have been posted on the Smartphone Pedagogy Page. The videos are available on YouTube and locally as iSpring presentations and .mp4 files. This series is sponsored by the American Astronomical Society.

The 2022 Nebraska Physics and Astronomy Fall Summitt will be held on Saturday, October 22, 2022. It will be held in Jorgensen Hall on the UNL city campus and the format will be similar to past offerings. People with programming contributions and suggestions are encouraged to be proactive in contacting the organizer Kevin Lee.

The simple simulation known as Switch is now available on the Smartphone Simulation page. It is very useful for tying together celestial equatorial coordinates and horizon coordinates and noting the locations of celstial poles in the sky for different latitudes.

Promotional materials for this year's (newly retitled) daylong workshop for local high school and college instructors of both physics and astronomy are attached. The workshop will be held in person at UNL and will be similar in format to previous workshops.

A public presentation — The Invisible Sky with JWST by Yoni Brande of the University of Kansas will be given the preceding evening (in person and on Zoom). A flyer with all details including the presentation abstract is available here.

The Saturday, October 16, 2021 workshop details are summarized here with the RSVP information. An early version of a schedule is provided here.

Yoni Brande of the University of Kansas will be giving a public presentation on the impending launch of the James Webb Space Telescope. The free presentation entitled The Invisible Sky with JWSTis scheduled for:

Friday, October 15, 2021
7:00 pm
UNL Union Auditorium and Zoom

A flyer with all details including the presentation abstract is available here.

A summer course for teachers entitled "ASTR 898: Phenomena of Planetary Satellites" is being offered in late June. All details are provided on the following flyer.

All Flash content has been removed from the site. More information on the necessity for this can be found on the Adobe Flash Player End of Life Page. Adobe states the following: "To help secure users' systems, Adobe will block Flash content from running in Flash Player beginning January 12, 2021."

It should be emphasized that all interactive content from the NAAP, ClassAction, and Interactive Ranking and Sorting Tasks projects is still available through Native Apps. These materials must be downloaded and installed on your local machine. They function in either WIN or MAC environments (but not on Chromebooks). They will continue to function as long as the underlying operating system allows them to function (which is likely to be many years) and they require no external plug-in. Although there are disadvantages to not having the materials available on the internet, there are also advantages to the new format. Advantages include the ease of accessing materials, the responsiveness of the materials, the ability to control simulation sizes, and guaranteed offline access.

The materials may be installed wherever you see benefit in doing so. At the University of Nebraska, all of the packages are installed on the machines of several classrooms, several public computer labs, and on the laptops available for student checkout across campus. They are also made available to students who are encouraged to install them on their personal machines. The native app executables for Win and MAC are available for download at Native Apps page. There are also short video tutorials on the installation process available and a simulation content guide illustrating which simulations are in the NAAP package and which are in the ClassAction package.

A new astronomy demonstration video has been uploaded focusing upon the luminosities and lifetimes of Main Sequence Stars. It is available on our YouTube Channel "UNL Astronomy" and embedded on the AU Demonstration Videos Page. It explores these issues using cars and sparklers as analogies for stars.

Statistics on this web site's usage have been tracked since the summer of 2008 using Google Analytics. Here is a posting of the 2020 data (which surprisingly looks a lot like the 2018 and 2019 data).

• 2020 Data
• 2019 Data
• 2018 Data
• 2017 Data
• 2016 Data
• 2015 Data
• 2014 Data
• 2013 Data
• 2012 Data
• 2011 Data
• 2010 Data
• 2009 Data
• 2008 Data

All 6 presentations association with the Fall 2020 joint Astronomy Education Workshop and Fall Meeting of the Nebraska Chapter of the American Association of Physics Teachers are now posted. They may be found on the https://astro.unl.edu/video/speakers/ page as embeded YouTube videos and on YouTube directly as part of the UNL Astronomy channel.

A new video has been uploaded on Eclipsing Binary Stars. It is available on our YouTube Channel "UNL Astronomy" and embedded on the AU Demonstration Videos Page. It simulates stars using special light bulbs and the variation in brightness with time of stars with different and similar sizes and surface temperatues.