Occultation Research Group

Presenting Findings from a Recent Occultation at the Annual Meeting of the Virginia Academy of Sciences (VAS) - May 28th 2026

Thu, 04 Jun 2026 00:00:00 GMT

import ImageWithCaption from '../../components/ImageWithCaption.astro'; import ImageGallery from '../../components/ImageGallery.astro'; On May 28th, 2026, two undergraduate members of the Occultation Group traveled to Christopher Newport University in Newport News, Virginia, to present scientific results from a stellar occultation. They were participating in the 104th annual meeting of the Virginia Academy of Sciences (VAS), and brought along with them a poster detailing the background, preparation, expedition, and analysis for the observation of a stellar occultation by (623) Chimaera, an asteroid which is selected for spacecraft fly-by in the early 2030s. The occultation occurred on October 21st, 2025, and a link to a news story and video report which covers this occultation in detail can be found here. The students, Diego Gomez and Colin Surovell, are two first-years at the University of Virginia and experienced members of the Occultation Group. Both have worked hard to obtain the data for this occultation and to analyze it. Diego Gomez applied himself to understanding the lightcurves which were created from each telescope's data. Lightcurves are graphical representations of the target star’s brightness before, during, and after the occultation. Gomez had this to say about the analysis experience: “I definitely learned how, even though we can plug our data into external tools, we were able to do it ourselves and actually see the shape of the asteroid from just the lightcurves. I feel like, since you can do that, it’s really accessible science for anyone to do. Pick a target, observe it, and plot it in this way–it’s an incredibly inclusive science.” Colin Surovell felt that the experience helped cement many of the scientific concepts which he uses in the research group. “I really enjoyed getting to show people our research. Putting together the poster was really helpful to me specifically; being able to put everything into a format which is so presentable helped give me a deeper understanding of the work that we do.” The conference itself was particularly exciting. Dozens of posters lined the tables of a gymnasium at Christopher Newport University, each bringing their own scientific story to the conference. “Presenting our work was satisfying–there were lots of people who worked in the field of astronomy and lots who worked in other disciplines, and it was really enjoyable to see that we were able to explain our research to people who didn’t have the specific background knowledge that we have,” reported Surovell. These results are being prepared into a scientific manuscript which is planned to be submitted to a peer-reviewed journal within the coming weeks. We are proud of our observers for representing our group so well at VAS! Clear skies, Teddy Oakey \ President, Class of 2026

Chasing Jupiter’s Moon Kallichore in the Outback - March 18th 2026

Mon, 13 Apr 2026 00:00:00 GMT

import ImageWithCaption from '../../components/ImageWithCaption.astro'; import ImageGallery from '../../components/ImageGallery.astro'; On March 12th, 2026, amidst feathery flurries of snow, eight members of the Occultation Group at the University of Virginia boarded a plane bound for Sydney, Australia. Just weeks before, we’d been contacted by researchers at the Instituto Astrofísica de Andalucía on behalf of the European Space Agency (ESA), asking us to collect data on Kallichore, a small, irregular moon of the giant planet Jupiter. Kallichore had previously only been observed through one other occultation and minimal astrometry. Huge orbital uncertainties and an essentially unknown profile made Kallichore somewhat of a mystery. Two years ago, the ESA launched a probe named the Jupiter Icy Moons Explorer (JUICE), which is set to visit three of Jupiter’s largest moons in the 2030s. The mission will study the potential subsurface oceans in these worlds, as well as investigate the possibility of habitability underwater. Interestingly, there is a possibility to redirect the JUICE spacecraft to conduct a flyby of Kallichore, but the ESA needs to know the precise location of Kallichore with much greater accuracy—which is where the Occultation Group steps in! Our observations will help refine Kallichore’s “astrometry”, as it is known, to within the desired range of the ESA for a JUICE flyby. Kallichore is especially interesting because it is part of the Carme group, a family of Jovian moons which are believed to be remnants of an object which originated from somewhere out past Neptune. Due to limited interactions with other bodies, the geologic and chemical conditions on Kallichore likely resemble those of the early outer Solar System. Studying this moon would offer valuable insights into these conditions at a relatively nearby location, possibly giving us hints as to how organic molecules made their way to our own planet. With this background in mind, we flew across the Pacific, traveling with four of our own telescopes. We would be collaborating with other teams traveling internationally, as well as domestic observers. The total efforts for this campaign consisted of fifteen telescopes. After over thirty hours of travel, we landed in Sydney. We had to wait several hours to check into our rooms, so after securing our luggage and rental cars, we made a beeline to the beach. In the comfort of a quiet cove, all our stress and aches seemed to wash off into the azure waters. That evening, we all worked together to cook a delicious meal—homemade chicken and noodles! This was the first of many “family dinners” we would have during our trip. Following dinner, we practiced setting up our telescopes, maneuvering them to the target star field, and locating the target star in our cameras. We were all amazed to see new constellations, such as the Southern Cross, as well as a few familiar constellations like Orion and Canis Major—but upside down! We would repeat this training process every clear night, troubleshooting problems with the mounts, optical arrays, and cameras; earning ourselves a deeper understanding of the quirks of each telescope with every passing day. The following day, we had some free time! The third and fourth years drove off to study at a cafe while the rest of us took a trip into Sydney. We spent hours walking along charming streets and appreciating the abundance of green spaces the city had to offer. We even got to see the Sydney Opera House, which rose from the waters like the pearly sails of a ship. Between sightseeing, homework, and training, our time in Sydney passed quickly, and soon we were on our way to our next destination, which would lie along the shadow path. We drove five hours inland to a small town in the Australian savanna, named Dubbo. This is where we hoped to base our operations. Any occultation has a selection of locations from which it can be seen from (see map below!), similar to how eclipses can be seen along a “path of totality”. We selected Dubbo as an ideal central location to base out of, since its location would allow us to either push farther inland or back to the coast to avoid cloud cover. On our roadtrip, we entertained ourselves with intensely competitive alphabet games. We enjoyed watching the landscape change from subtropical greenery, to craggy mountains, then to rolling green hills, and finally to the grassy savanna. We found Dubbo to be a wonderful little town, with friendly locals, a nice zoo, and its own observatory! We had reached out ahead of time to collaborate with them, since as luck would have it, Dubbo Observatory was located directly under the shadow path. We provided our cameras and timing equipment to the operator of the observatory, and attached them to a very nice seventeen-inch PlaneWave telescope. On the days leading up to the occultation, tension started to rise. As we watched the weather forecast, clouds expanded across the entire country. At one point, we were prepared to drive a whole day's trip inland in search of clear skies, but recent rains had washed out many of the country roads which we would have used to reach observing sites in central Australia. As the forecast developed, it would become clear that we would have ill luck across most of southern Australia. We communicated with the other teams participating in this observation to distribute ourselves across the shadow path, spaced from one another by approximately 100 kilometers each, so that there might be a chance that one of our teams would catch a break in the clouds. Our eight observers spent the afternoon scouting on Google Earth, as real-time satellite imagery would inform us on where small pockets of clouds might appear. We ended up selecting over eighty potential sites to observe from across the state of New South Wales. On March 18th, 2026, the night of the event, all four teams from UVA set up at different locations in the Dubbo area. My teammate and I were dropped off on a small dirt road in the grasslands, and set up our telescope under ominous, dark grey clouds, watching as lightning threatened in the distance. About half an hour out from the event, rain drops began to fall. After debating for a few minutes, we reluctantly but confidently made the call to take down our equipment, worried about the damage rain could inflict upon the electronics. We worked quickly, throwing our jackets over the mount, battery, and laptop to protect them from water. Unfortunately, all of our teammates faced the same weather issues and we returned frustrated, yet proud of our efforts. Though we were all a little downtrodden, we also acknowledged that this was the way scientific research often goes. If we could control the weather, we would, but experiences like these are what make successful expeditions all the more sweet! As it turned out, we would have had to travel to the opposite coast of Australia, over two thousand kilometers away, in order to catch clear skies. The following day, we packed up and returned to Sydney. As I sat in the car on the way back, I reflected on the trip. I was surrounded by people who, many of whom had started off as teammates or friendly acquaintances, but now had grown to be some of my closest friends. The following day we all went out for a delicious water-side brunch together. This was our last full day in Australia and we decided to make the most of it. Following brunch, I went with a few others on a hike in the Royal National Park. Throughout the hike, we traced the edge of a cliff, looking down into the deep sapphire waters of the pacific. The path was surrounded by a dense carpet of subtropical brush, reaching as far as the eye could see. As we progressed along the path, we were met by views of shimmering waterfalls which ran down the sides of the cliff, interrupted by misty rainbows. Humongous waves crashed against craggy rocks and the ocean seemed to disappear into the blue sky. This was by far one of the most beautiful places I’d ever been! As I flew back to Charlottesville the next day, I thought over the experiences we’d had again. I’m so incredibly grateful to have had the privilege to have been able to take part in this mission. I comforted myself with the knowledge that in all of our efforts, we were successful. If not for the weather, we would have come home with exactly what we came for. The Occultation Group at the University of Virginia would like to gratefully acknowledge support for this expedition from the Instituto Astrofísica de Andalucía, the European Space Agency, the Jefferson Trust, and the UVA Parents Program/Student Council. Your contributions have made all of our works possible, and we are incredibly grateful. Georgia Clickner \ Editor, Class of 2029

Characterizing the Emirates Mission to the Asteroid Belt target (269) Justitia from the United Arab Emirates - January 13th 2026

Mon, 09 Feb 2026 00:00:00 GMT

import ImageWithCaption from '../../components/ImageWithCaption.astro'; import ImageGallery from '../../components/ImageGallery.astro'; On January 13, 2026, twelve students from the University of Virginia (UVA), around seventy observers working with the Sharjah Academy for Astronomy, Space Sciences and Technology (SAASST), and several members of the Southwest Research Institute (SwRI) started recording data for the occultation of asteroid (269) Justitia in the United Arab Emirates, one of the Occultation Group’s furthest expeditions yet. However, this expedition didn’t start here—for many of us, it began many months prior: planning logistics for a trip to a country halfway around the world, reviewing weather forecasts, collecting funds to support the trip, and selecting the students who would attend. A week prior, while many Hoos were relaxing during their winter break, members of the Occultation Group left their homes, with telescopes in tow, and ventured to the Emirates! This expedition was a collaboration among SwRI, SAAST, and the UAE Space Agency (UAESA), which plans to launch the Emirates Mission to the Asteroid Belt (EMA) in March 2028. The mission is set to visit seven main-belt asteroids, orbiting the final target and deploying a lander on its surface. That final asteroid is named (269) Justitia, and is one of the reddest asteroids in the main belt between Mars and Jupiter. This leads some to believe it is a captured body from the outermost regions of the Solar System, where such red planetesimals are common. As this asteroid would be part of the Emirates Mission to the Asteroid Belt, its orbit had to be mapped well—any incorrect prediction could alter the trajectory of the probe. Additionally, oddities displayed in a previous occultation hinted at a possibility of a satellite—if there was one, there was a good chance it would also occult the star on January 13th. On the seventh, we landed in Dubai, and nine out of the twelve UVA students met at the airport. Four of us went north to stay in Ras Al Khaimah with our Vice President Keya Garg’s family, while the rest of us drove south with the help of local member Vasilisa’s drivers, Irene and Rona (thank you!). Driving out of the airport was a surreal experience—the first things I noticed were that all the signs were in Arabic and English, and the scale of everything around us immediately felt unreal. As we headed closer to the city, the skyline came into view, and I could make out the spire of the tallest building in the world—the Burj Khalifa! Driving to our residences, three of us stayed at a hotel, while Mark Chernov and I continued to an apartment in downtown Dubai, where we would wait for Matthew Walls and Charles Dorsey to join us later that week. Our balcony on the 18th floor gave us our first chance of relaxing and enjoying the beautiful view of the Palm across the water. On our first day, we drove through downtown to get to the Sharjah Academy. Instead of the typical building layout I expected, the premises acted as a solar system with a large golden-domed central building representing the sun and a large lawn encompassing it with painted spheres acting as the Solar System’s planets “orbiting” it. Outside of the “Solar System”, in a building behind a futuristic set of doors that looked like they stepped out of Star Wars, were the team’s 34 telescopes—thirty CPC1100 systems from SwRI and four Celestron 11” telescopes from UVA—recently assembled thanks to a generous grant from the Jefferson Trust. With the systems fresh off delivery, we had to get to work downloading, updating, and configuring the right software on each computer, along with ensuring everything was in place. Many of the telescopes SwRI brought with them were last deployed in Wichita, Kansas as part of the Occultation Group’s recent expedition this summer to observe (59980) Moza, another target of the EMA. Here we were also able to meet the leads from the UAE behind the trip, Hoor al-Mazmi and Anoud al-Zaabi, along with the members of SwRI that had organized this mission, Marc Buie and Brian Keeney (who is a UVA alumnus!). It had been decided that the UVA occultists would be split—the four members of the executive team would be spread out among the local observers, while the remaining eight members were split into four teams of two that would handle the Celestron 11" telescopes. All four of the UVA teams were set near the expected bounds of the asteroid, with the apartment team being in the south and the other two teams being in the north. My partner would be first-year student Matthew Walls, meaning that we would share the responsibility of assembling a telescope and recording the occultation alone in the desert. After completing business for the day, we headed to this fantastic, authentic restaurant that gave me a taste of the local cuisine—Hardee’s! Although it was a taste of home, it was actually the first time trying it for the majority of us (would recommend!). Naturally, after enjoying the comforts of American fast food abroad, we threw ourselves straight into dune bashing! Off-road, high-speed driving across the Emirati dunes, twisting and turning along the shifting terrain. The ups and downs made my stomach do somersaults. After bashing, we came together for a buffet featuring a show by a fire dancer! The dinner was our genuine first taste of food here, and we had the option of lamb, beef, dumplings, fried rice, and more. The show impressed us throughout the meal, and several undomesticated cats joined us for the event—whether to enjoy the show or steal our food, we will never know. That night, as Teddy put it, we were able to “sleep in” until 4:30 am. Call time was at 6 am in Sharjah, and both Matthew and Vasilisa would join us by morning. Here we met all the local members of the expedition, ranging from people who have never touched a telescope before to others who were studying astrophysics. I personally had the chance to briefly meet several members, one of whom mentioned his interest in astrophotography and his own AM3 telescope system that he used. Being in an entirely new country also allowed me to further explore one of my interests—bird watching! Luckily, I had packed my personal pair of binoculars, so I was prepared for any feathered friend that came my way. Although right next to the desert, Sharjah still had a wide variety of birds, including many colorful ones such as the Superb Sterling (as seen below), which was a frequent visitor to the Academy. Its vibrant blue back, combined with its fiery orange belly, drew my attention to it each time it visited. The following day was our first 1:30 am wakeup for our 3:00 am meetup. As we were nine hours ahead, our bodies felt like we were falling asleep at 9:00 am and waking up at 4:30 pm. We set up telescopes for the first time outside, with the trainers walking around to anyone who needed help, while the UVA teams assembled telescopes on our own, spending a few hours fully assembling and disassembling our systems, troubleshooting hardware, collimating our optics, and debugging software issues. After a few hours spent discussing logistics, log sheets to track data, and more, the UVA team travelled to the coast, where we finally had our own beach episode! Charles had finally arrived from London and met us there, giving the whole group their first chance to relax together. Back at the residence, Mark cooked his signature dish, a delicious salmon (or as he would say, sal-min), that the team staying at the apartment desperately needed. The goal of the next day was to meet at 3:00 am and be fully assembled and on the star field by 4:00 am, and a majority of the teams did just that! I was really impressed with the whole group, as many of the people were completely new to the systems and managed to get a full grasp on them in just a few days. Discussion of choosing sites followed, and the teams hit the road to locate the site they would be using on event night. Charles Dorsey, Mark Chernov, Matthew Walls, and I rode together and, after a few sub-parspots, found our sites. Matthew and my site was a large dirt field right next to a farm (with the fresh smell of manure, yum!). Mark and Charles had a bit worse luck and ended up having to go with a clearing in the middle of the desert that had a long, 20-minute off-road adventure to get to. On our way to the sites, we had the chance to see a bunch of local wildlife, including a lot of camels just chilling around and a few small herds of sand gazelles. Dress rehearsal occurred the following day, which is when, on the day before the occultation, we do a rehearsal of exactly what we would be doing during the event. We got to the site a few hours early, set up, and recorded data at the time it would be at tomorrow. Matthew and I had ample time before the event, so we were able to look at some constellations in the night sky. The sky was looking pretty hazy when we got to the site, which gave us some worries for tomorrow, but it managed to clear up around half an hour out. Coming back to Sharjah, I learned that the entire group had around a 75% success rate! Hearing that was crazy and really showed me how well and organized SwRI runs things, taking inexperienced observers to successful ones in just a few training sessions. As it was our last chance to do touristy things, a bunch of us headed over to the Dubai Mall to hit a bunch of the things on our travel list—see the Burj Khalifa up close, get gifts for friends at home, and of course, eat some authentic Dubai chocolate. We headed back home to make sure we got an early rest for the event tomorrow—we were all so excited for the big day! Event day! Months of planning, weeks of assembling telescopes, days of training astronomers, all led up to this. The teams left early, with Matthew and I arriving on site by 2:00 am, and Mark and Charles arriving before 2:30. Since Matthew and I were one of the southernmost chords, we were expecting a constraining negative; however, we saw the star blink out! Three out of the four teams saw a positive, while Georgia and Vasilisa’s team saw a constraining negative (i.e. the star did not blink out), which is extremely valuable data, as it tells us precisely where the edge of the asteroid is located. The mission was a success! We look forward to sharing the final profile when it has been peer-reviewed and published, but currently it is under scientific embargo. The team enjoyed their final day in the UAE, attending a fabulous lunch at a tea house hosted by Hoor al-Mazmi. The group packed up and, taking one last walk around, enjoyed a final sunset. We all made our way back to the airport, taking off with some of us going through Frankfurt, others through London, all to get back to UVA in time for the fourth day of classes. It was such an amazing trip, and it would not have happened without the fantastic people involved. We would like to share our appreciation towards the Parent’s Program, the Jefferson Trust, the UVA Student Council, and the College of Arts and Sciences Small Research and Travel Grant program for their dedicated support of our group and our mission to pursue asteroid science all across the world. John DiPasquale \ Observer, Class of 2028

October 21, 2025 – Largest UVA Group Expedition to Observe Occultation by (623) Chimaera

Sun, 28 Dec 2025 00:00:00 GMT

import ImageWithCaption from '../../components/ImageWithCaption.astro'; import ImageGallery from '../../components/ImageGallery.astro'; On October 21, eight UVA teams traveled to North Carolina to observe the occultation of asteroid (623) Chimaera. The eight UVA teams involved eighteen students total, making this trip the largest out-of-state expedition the Occultation Group at UVA has ever had! The asteroid target, Chimaera, is a main-belt asteroid that is estimated to be approximately 44.1km in diameter, comparable to the size of Rhode Island, and making it larger than 99% of asteroids! This asteroid is particularly interesting because it is a target for the upcoming Emirates Mission to the Asteroid Belt (EMA) planned to launch in March 2028 by the UAE Space Agency. Ground-based observations are crucial to get preliminary data on Chimaera to help plan for the EMA mission. The eight UVA teams worked along with nine other observing teams from across the United States. The UVA teams set up eight telescopes total in the area surrounding Charlotte, North Carolina. In total, there were eighteen telescopes set up across the United States to observe Chimaera. The UVA teams left Grounds on Monday, October 20 around 8:00 pm local time to set up in North Carolina. Set-up went smoothly for all eight UVA telescopes and the sky had minimal clouds in sight. Chimaera was so bright that it could’ve been mistaken as a star through the telescope! All UVA telescopes started capturing data at 07:13:40 UTC (03:13:40 local). Seven out of eight UVA telescopes watched as the asteroid approached and partially occulted the target star, causing a 48% drop in the star’s brightness along the central line of the asteroid's path. One of the UVA telescopes didn’t observe the occultation, but these negative results are very crucial in understanding the boundaries of the asteroid’s size. As a whole, all but two telescopes across the United States successfully captured data. Out of sixteen successful data captures fourteen were positive and two were negative. The two negatives were located at the upper and lower boundaries of the asteroid; these two negatives will help us understand the size of Chimaera during data analysis. Unfortunately due to technical issues one telescope observed the initial dimming of the star as Chimaera began occulting the target star, but could not observe the reappearance of the star at the end of the occultation. However, this expedition was still overall a great accomplishment. After the successful mission, the UVA teams all went to Waffle House at the prime time of 5:00 am to celebrate with waffles and bacon! However, the expedition was not over yet. As we waited for our food, we already started working on preliminary data analysis. These preliminary flux vs. time lightcurves taken by each UVA telescope all turned out beautifully. The following image depicts a lightcurve of Chimaera gathered by one one of the UVA telescopes during the expedition. Using all the lightcurves captured from each telescope, a skyplane plot can be made to visually show the size and shape of the asteroid. This plot depicts each of the telescopes’ view or chord as a straight line on the plot; this line will disappear at the time the respective telescope observed the start of the occultation and reappears when the occultation ends. With multiple cords put together, this plot essentially draws a picture of what the asteroid’s 2D shadow looks like. Skyplane plots can show Chimaera’s topographical features and any special characteristics that researchers might want to focus on in the future. Data analysis is still on-going, so many things have yet to be explored. We plan to release updates once analysis is complete, so make sure to keep an eye out! It is hoped that these ground-based observations for Chimaera assist in the preliminary analysis of the asteroid, preparing for when we get the chance to see Chimaera through the eyes of the EMA Explorer in 2028! Lauren Daszynski \ Observer, Class of 2029

September 30, 2025 — Occultation by Ringed Kuiper Belt Object (50000) Quaoar

Wed, 10 Dec 2025 00:00:00 GMT

import ImageWithCaption from '../../components/ImageWithCaption.astro'; import ImageGallery from '../../components/ImageGallery.astro'; On September 25th, 2025, four members of the Occultation Group packed their bags with tents, camping gear, a telescope, and just enough clothes to survive a week ahead on the tropical island of Kauaʻi, on the far west of the U.S. state of Hawaiʻi. We had a busy trip ahead of us, and excitement was tangible in the air! We were traveling into the central Pacific Ocean to observe a stellar occultation (transit of a star, much like an eclipse) by the fascinating object (50000) Quaoar, a dwarf planet in the outermost regions of the Solar System. Quaoar is a dwarf planet roughly 1000 km in diameter—or 600 miles—which is about half the size of the ex-planet Pluto. Quaoar has at least one small moon, Weywot, but more interestingly, possesses a very unique set of rings. Rings are common around the larger planets, famously Saturn, but have only been shown to exist around three rocky bodies in the Solar System. In all three cases, especially in the case of Quaoar, these rings can only be detected by watching them pass in front of a star during an occultation, and looking for small diffraction effects in the data as the rings bend and interfere with the starlight. The rings are especially odd in that at least one of them exists beyond the Roche limit of Quaoar, which is the theoretical radius where rings should be able to stably exist around a planet (and recent occultation results suggest even another ring even farther out!). Observing and characterizing these rings was the objective of our expedition! Usually, these diffraction effects are only observable with telescopes between 1-2 meters, and the largest telescope in our arsenal is 0.61 meters, which is not quite enough! To make up for the difference in telescope size (aperture), we planned on observing the occultation with as many telescopes as possible from the same location, combining their mirrors to act as one single large telescope! Of course, transporting many telescopes from Charlottesville is logistically and financially challenging, so we elected to ship only our largest 0.61 m telescope, and carried a smaller, 0.28 m telescope through checked baggage. To make up for the remaining aperture, we contacted the Kauaʻi Educational Association for Science and Astronomy (KEASA), a local astronomical society located on the western coast of the island, who operate an observatory complex on the Pacific Missile Range Facility (PMRF), a large Navy base near the towns of Waimea and Kekaha. Located in the KEASA observatory complex on the PMRF are a series of telescopes: a 0.51 m Dobsonian, a 0.43 m Dall-Kirkham Cassegrain, and a 0.25 m Newtonian. A local member of the KEASA provided a mobile 0.36 m Dobsonian telescope as the final piece of the puzzle. Calculating the combined circular area of each of these telescopes brings our total aperture size to 1.01 meters, theoretically large enough to detect small wobbles in the starlight indicative of ring presence. After a short layover in Denver, we slowly descended onto the Aloha State and excitedly hopped off the plane, grabbed our rental car, and ate some delicious saimin on the way to our first hotel: a mountaintop in the rainforest! Budgetary restraints meant our options were limited for most of the days of the trip, but camping permits were well within our budget and we booked a remote site at the top of the scenic Waimea Canyon. Just as our luck would have it, rain began to fall as we drove up the hazardous road and we had just enough time to set up our tents as the storm picked up. Our first night was long and wet, and one of the tents collapsed under the storm, soaking our poor vice president, who moved into the warm car for the remainder of the night. The rain did not let up on day two, and the conditions of the roads had degraded to the point that we did not feel comfortable driving back to town, so we made the most of a cold and wet situation and explored the nature reserve! We trekked down to a river, following it to an enormous waterfall with large irrigation infrastructure. Everywhere we went, raw ginger grew out of the ground and was blossoming! That evening, as I settled in my tent under light rainfall, I drifted off to sleep—only to be shaken awake an hour later by excited whispering: the stars had come out! We spent the next few hours under one of the brightest night skies I have ever seen. I attached my DLSR camera with rubber bands to the telescope mount and took several long exposure pictures of the Milky Way. We eventually retired to our tents, since we had an early morning. Waking up at four a.m. is never easy, but the view made everything worth it. We were rising so early in the hopes of catching an occultation by a different asteroid to test all of our equipment, but were treated to something I never expected to see: stretching up to the planet Venus just before twilight was an exceptionally faint band of light– when I noticed it, I gasped. It was what is known as the zodiacal light, and is the result of sunlight reflecting off of the sparse interplanetary dust in the plane of the Solar System (kind of like a very faint version of Saturn’s rings, but on the scale of the Solar System). It can only be seen with the naked eye from the darkest sites on the surface of the Earth. Truly a treat! The Sun began to rise and we were finally able to see where we were camping- we had no idea we were on the edge of a cliff! About twenty feet away, the ground gave way to a three-hundred foot deep canyon. A magnificent sight. The rain would stay off all day and night, and the following day we were able to return to town. We continued rehearsal with our telescope at night. The final two days were all business– we spent all day ensuring all of the equipment we would equip the KEASA telescopes with were in tip-top shape, batteries charged and GPSes calibrated. The need for electricity meant we were staying in an AirBnB for the final part of the trip. Once our host, Captain James Dire, arrived, we spent our penultimate afternoon on the PMRF familiarizing ourselves with the two telescopes we could access and that were compatible with our cameras and computers. Everything was going smoothly! The next night was the big day! The occultation was scheduled to occur at approximately 8:30 p.m. local time; the four telescopes we already worked with were good to go, and we had just over three hours to configure the other two telescopes to run in time. These new two were enigmatic– they were unmotorized, which meant that their owners, local KEASA members, would have to move the behemoth telescopes by hand! Keeping an eye on a computer screen, identifying a tiny, faint target star, and pushing a twelve-foot telescope by hand every thirty seconds is a monumental task, especially for a first-time occultist. Even more troublesome was that one of the telescopes didn't seem to come into focus with our camera installed, but Andrey Moore was able to save the day with some quick MacGyver-style thinking, rotating the placement of each camera+computer+timer system between the telescopes just twenty minutes before we started to capture our data. Because Quaoar is so far away, it moves much slower in its orbit and will typically occult a star for around 60-80 seconds (also due to its enormous size), which is much longer than small, nearby asteroids, which typically will occult for about a second or two at most. However, the relative motion of Earth and Quaoar meant that Quaoar was approaching retrograde, meaning the two planets were moving in the same direction, which means that occultations during this period could be three or four times as long as normal. In this case, the maximum predicted duration for the occultation was about three minutes! This made this particular occultation particularly exciting for ring science, since the rings would be passing in front of the star for three times as long as well, and we could gather more signal in our detector. Because of how far our the rings are, we would need to record for fifteen minutes on either side of the main body occultation to make sure we captured any interesting event. Sure enough, all six telescopes were prepped and ready for the occultation just in time, and each team (with some close calls) managed to observe for the full thirty minutes– and everybody saw the occultation! In order to say anything definitive about the rings, we will need to bin and stack the data from each telescope on top of one another, but we are interested to see what the data show! We look forward to updating this article when more information is available. We would like to share our appreciation to the KEASA and PMRF for their facilities support in this expedition, the Outdoors Club at UVA for camping supplies, and the Parent’s Program and SAF funding for financial support for travel and equipment expenses. Clear skies, Teddy Oakey \ President, Class of 2026

Astronomy students travel the world to peer deep into space

Mon, 15 Sep 2025 00:00:00 GMT

Matt Kelly writes about the Occultation Group and our mission.

Final Campaign to Observe Stellar Occultation by 59980 1999 SG6

Fri, 05 Sep 2025 00:00:00 GMT

import ImageWithCaption from '../../components/ImageWithCaption.astro'; import ImageGallery from '../../components/ImageGallery.astro'; Through a collaboration with Dr. Marc Buie of the Southwest Research Institute (SwRI), who generously provided 12 CPC1100 systems for UVA and local observers, the Occultation Group at UVA organized an 18 telescope deployment in the +/- 3-sigma zone. ## Technical Details This 18 telescope deployment proved to be a daunting logistical challenge. For us UVA observers, it was the first time we set up unmanned telescopes for a campaign to automatically collect data at event time. For the eight telescopes set up by the UVA group, seven were able to successfully collect data with one unmanned station unfortunately drifting off the star field before the event time. ## Observer Overview - Phillip "Teddy" Oakey and Keya Garg: Four CPC1100 telescopes (two unmanned) - Andrey Moore: Two CPC1100 telescopes (one unmanned) - Uday Kapoor: Two CPC1100 telescopes (one unmanned) - Kai Getrost: One 20" personal telescope - Gary Hug: One personal telescope - Marc Buie: Two CPC1100 telescopes - Vadim Nikitin: Two CPC1100 telescopes - Brian Heimes and Chet Batterman: one CPC1100 Telescope - Roger Venable: Three 14" telescopes. ## Next Steps As this was the final domestic occultation of this asteroid before the mission launches, all we have left to do is finish our analysis of the observations and compile a profile of the asteroid. More updates will come as we continue to profile this mission. We plan on releasing a vlog for the event in the coming weeks which will provide much more insight on our travel and data collection processes for this event. Andrey Moore \ Secretary, Class of 2027

June 1, 2022 Pluto Occultation

Thu, 02 Jun 2022 00:00:00 GMT

import ImageWithCaption from '../../components/ImageWithCaption.astro'; import ImageGallery from '../../components/ImageGallery.astro'; Unlike the asteroids that the group typically observes, Pluto harbors an atmosphere. When Pluto occults a star, this atmosphere refracts the light of the star, resulting in a "central flash" in the middle of the occultation (see Figure). The strength and shape of this flash depend on the pressure and temperature of the atmosphere, and hence occultations are a way of studying Pluto's atmosphere. Previous occultations of Pluto were observed in 2007 and 2018, so the occultation in 2022 provided an opportunity to see if Pluto's atmosphere has changed over the past 15 years. The central flash is most prominent at the chord that passes directly through the center of Pluto, and in this occultation the centerline passed near Katherine, Northern Territory, Australia. Liam and Becky joined a group from SwRI, led by Leslie Young and Eliot Young, at Katherine Rural Campus. Several students from a nearby university joined as well. During the days, the group explored the campus (lots of farm animals), enjoyed the Australian wildlife (many wallabies!), and went swimming in a beautiful nearby gorge. During the evenings, they practiced setting up the telescopes and observing Pluto. On June 1, 2022, after several nights of practice, the teams set out to observe the occultation. Liam was on a team with Mike Skrutskie observing near Katherine, and Becky was on Anne Verbiscer’s team about an hour north of Katherine. It was hot and muggy, despite it being the early hours of the morning, and when Becky's team started setting up the sky was cloudy. Fortunately, in the hour leading up to the occultation, the clouds began to clear, and the team was able to align the telescope, and finally get on field, in time to observe the event. They watched the star slowly dim, and then slowly reappear, as Pluto passed in front of the star, with the entire occultation lasting several minutes. At their site north of Katherine, Becky's team was too far from the centerline to observe a noticeable central flash, but the team that Mike and Liam were on was more fortunate. They observed a bright central flash, over 2.5 times the brightness of the star. In addition, they observed with two telescopes - one 51-cm equipped with a red filter, and one 61-cm equipped with a blue filter. In total, 15 telescopes were set up to observe Pluto: 8 near Katherine, 3 additional in Australia, and 4 in Indonesia. Analysis of the results, particularly the central flash observed by Liam and Mike's team, suggest that Pluto's haze opacity has changed from 2007 to 2022 and that Pluto's atmosphere may be experiencing freeze-out (Young et al. 2023, DPS presentation). However, data analysis is still ongoing, and one mystery that remains is the narrowness of the central peak compared to models (Young & Young, 2025). Becky Williams \ President, Class of 2024

March 27, 2022 Polymele Occultation

Mon, 28 Mar 2022 00:00:00 GMT

import ImageWithCaption from '../../components/ImageWithCaption.astro'; import ImageGallery from '../../components/ImageGallery.astro'; On March 27, 2022, three UVA teams traveled to North Carolina to observe asteroid (15904) Polymele. Polymele is a Jupiter trojan asteroid and one of the targets of the NASA Lucy mission. Occultations by these mission target asteroids are extremely useful for pinpointing their locations and determining their shapes and sizes ahead of time. The more that we know about an asteroid before Lucy arrives, the better the Lucy team can plan Lucy's flyby to target any interesting features an asteroid might have. The three UVA teams joined 23 additional teams throughout the US to observe Polymele occulting a distant star. Mike Skrutskie took one telescope, Matt Nelson another, and student team Liam Walters and Becky Williams a third. The three teams loaded up the telescopes and drove from Charlottesville, Virginia to Rockingham, North Carolina, close to the border with South Carolina. The night was clear, and all three telescopes were lucky enough to observe a positive! Liam and Becky observed a “double hit” (meaning the star blinked out twice), suggesting that Polymele looks more like a peanut than a simple round ellipsoid. Together, the three UVA cords helped constrain the northern edge of the asteroid. Over the next few days, analysis of all 23 teams' data revealed an additional exciting find: two of the non-UVA teams had caught an occultation by a small satellite asteroid located about 200 km from Polymele! This satellite is too small and too close to Polymele to be observed with any method other than occultations, and the discovery prompted ongoing follow-up occultations to observe the satellite a second time. The goal is that Lucy will be able to visit both Polymele and its satellite when it flies by in 2027. Becky Williams \ President, Class of 2024