UConn is now home to tools that have played an instrumental role in mapping the universe — 10 large aluminum plates used as part of the Sloan Digital Sky Survey (SDSS). Measuring 32 inches across, one-eighth of an inch thick, and with thousands of tiny holes drilled in them, these plates may not be the type of instruments most people would initially picture; however, they have helped answer important questions about the universe.
Jonathan Trump, associate professor of physics, helped design the final round of plate observations for SDSS, which observed over three million objects in the sky, including stars, galaxies, and supermassive black holes from a telescope in New Mexico.
Akhshik gleans new information about very distant galaxies using a phenomenon called gravitational lensing. Due to the forces of gravity, light from distant galaxies is focused to appear brighter, and the images appear in different parts of the sky at different times, explains Akhshik. The researchers were also able to detect new details of distant galaxies through observations from different telescopes, which Akhshik says is almost like layering different filters on the same image.
Physics major Nicole Khusid, a rising senior at UConn, was featured in a UConn Today article about her research. Nicole has been working on gravitional lensing of distant sources of gravitational waves, seeking to understand their multimessenger signals and detectability by future astrophysics facilities. Nicole was awarded a SURF (Summer Undergraduate Research Fund) award to perform this research wtih Prof. Chiara Mingarelli. For the full story, see the article in UConn Today.
New Physics PhD graduate Yasaman Homayouni is featured in a story on the class of 2021 from the College of Liberal Arts and Sciences (CLAS). For the full story of what inspired Yasaman and other students during their time at UConn, see the article in UConn Today.
November 2, 2020 – Elaina Hancock – UConn Communications
The Sloan Digital Sky Survey’s fifth generation – a groundbreaking project to bolster our understanding of the formation and evolution of galaxies, including the Milky Way – collected its very first observations on the evening of October 23.
Image: The Sloan Digital Sky Survey’s fifth generation made its first observations earlier this month. This image shows a sampling of data from those first SDSS-V data. The central sky image is a single field of SDSS-V observations. The purple circle indicates the telescope’s field-of-view on the sky, with the full Moon shown as a size comparison. SDSS-V simultaneously observes 500 targets at a time within a circle of this size. The left panel shows the optical-light spectrum of a quasar–a supermassive black hole at the center of a distant galaxy, which is surrounded by a disk of hot, glowing gas. The purple blob is an SDSS image of the light from this disk, which in this dataset spans about 1 arcsecond on the sky, or the width of a human hair as seen from about 21 meters (63 feet) away. The right panel shows the image and spectrum of a white dwarf — the left-behind core of a low-mass star (like the Sun) after the end of its life.Image Credit: Hector Ibarra Medel, Jon Trump, Yue Shen, Gail Zasowski, and the SDSS-V Collaboration. Central background image: unWISE / NASA/JPL-Caltech / D.Lang (Perimeter Institute).
“In a year when humanity has been challenged across the globe, I am so proud of the worldwide SDSS team for demonstrating — every day — the very best of human creativity, ingenuity, improvisation, and resilience. It has been a wild ride, but I’m happy to say that the pandemic may have slowed us, but it has not stopped us,” says Juna Kollmeier, director of the project known as SDSS-V.
The project is funded primarily by an international consortium of member institutions, along with grants from the Alfred P. Sloan Foundation, U.S. National Science Foundation, and the Heising-Simons Foundation.
Jonathan Trump, UConn assistant professor of physics, has a long history with SDSS, and is one of the architects for the fifth installment of the program. He is also serving as the cadence coordinator for the project’s black hole science goals.
“My very first undergrad research project was an SDSS project. I have worked on SDSS as a post-doc, and I am working on it now as faculty,” Trump says. “I’ve been part of it from the first SDSS iteration, and as it has taken off, so has my career.”
Trump and his colleagues will focus on three primary areas of investigation with SDSS-V, each exploring different aspects of the cosmos using different spectroscopic tools. Together, these three project pillars—called “Mappers”—will observe more than six million objects in the sky, and monitor changes in more than a million of those objects over time.
The survey’s Local Volume Mapper will enhance our understanding of galaxy formation and evolution by probing the interactions between the stars that make up galaxies and the interstellar gas and dust that is dispersed between them. The Milky Way Mapper will reveal the physics of stars in our Milky Way, the diverse architectures of its star and planetary systems, and the chemical enrichment of our galaxy since the early universe. The Black Hole Mapper will measure masses and growth over cosmic time of the supermassive black holes that reside in the hearts of galaxies, as well as the smaller black holes left behind when stars die.
Trump says another novel aspect of SDSS-V is repeat observation, which he will be scheduling over the duration of the project as cadence coordinator, to help gather more data about the evolution of different features of matter near black holes.
“SDSS-V has more repeat observations as part of the plan. I would say that broadly in astronomy there is an emphasis on repeat observations,” he says. “For instance, black holes are fascinating – they are rips in space-time, and they are extremely exotic. Even one snapshot reveals how exotic they are, but they are also dramatically variable, and when we observe them day-to-day, week-to-week, year-to-year, we see dramatic changes in their emission, which we think correspond to dramatic changes just beyond the event horizon of the black hole. We are learning that you can reveal a lot about the physics of what is going on around black holes by watching them as a function of time.”
SDSS-V will operate out of both Apache Point Observatory in New Mexico, home of the survey’s original 2.5-meter telescope, and Carnegie’s Las Campanas Observatory in Chile, where it uses the 2.5-meter du Pont telescope. SDSS-V’s first observations were gathered in New Mexico with existing SDSS instruments, as a necessary change of plans due to the pandemic. As laboratories and workshops around the world navigate safe reopening, SDSS-V’s own suite of new innovative hardware is on the horizon—in particular, systems of automated robots to aim the fiber optic cables used to collect the light from the night sky. These will be installed at both observatories over the next year. New spectrographs and telescopes are also being constructed to enable the Local Volume Mapper observations.
Trump points out that another important aspect of SDSS, especially in a time of remote learning and researching, is the fact that data are made public and accessible.
“It is easy to access and mine the SDSS databases and make interesting studies,” he says. “They have wonderful tutorials for schools and for researchers to get started. They make it so easy for people to dive in. It is a very rich opportunity; it’s well organized and publicly shared.”
To learn more about the program, explore the data, or keep up with the research, visit https://www.sdss5.org/
This article first appeared online on UConn Today, November 2, 2020.
UConn graduate student Gloria Fonseca Alvarez was featured with a video in the Author Interview series produced by the American Astronomical Society (AAS):
In this video, Gloria talks about her work to understand the inner environments of black holes. The paper highlighted in the video shows that the orbits of emission-line gas around supermassive black holes are often smaller than expected from previous observations. We’re very proud to see Gloria’s exciting work recognized in the AAS Author Series!