ASTRO

Posts related to astronomy and astrophysics research

Astronomer Jonathan Trump interviewed on UConn 360

UConn Astrophysicist and observational astronomer Jonathan Trump was a recent guest on UConn 360, a podcast from the Storrs campus of the University of Connecticut. In this conversation, Jonathan tells about how attending a lecture as an undergraduate at Penn State captured his interest and changed the course of his professional career. Now Jonathan offers similar career-changing opportunities to UConn students, who just this year have applied for and obtained dedicated time for observations by the Hubble space telescope.

Amelia Henkel, Graduating President of the Undergraduate Women in Physics Club, speaks about her time at UConn

 

Amelia Henkel, graduating Double Major in Physics and Human Rights, and President of the Undergraduate Women in Physics Club, speaks on the CLAS website about her passion for physics and human rights, and how she mastered challenges in her remarkably interdisciplinary curriculum. “We really need to interact with other disciplines,” says Amelia, “because that’s when physics has the opportunity to make a real impact on the rest of the world.” Her broad research interests range from A to W: from Astronomy to Women’s, Gender, and Sexuality Studies. “Respecting and promoting human rights is a prerequisite to realizing our full potential as human beings,” says Amelia. Physics as a discipline has made progress to become more inclusive, but many groups remain minorities including women. In daily college life in physics departments female students still face “microaggressions and discriminatory practices” which are often unintended and unconscious but nonetheless damaging and frustrating.  As the President of the Undergraduate Women in Physics Club, Amelia helped to organize “events that promote community cohesion and inform the students about the nature of some of the barriers that exist in physics and in STEM, while talking about how we can overcome them.” The recent department-wide event Women in Physics Colloquium organized by Amelia was thought provoking and well-received. The percentage of women earning a Bacheleor’s Degree in Physics from UConn, though slowly increasing and compatible with the national average of about 20% published by APS, is far away from where we wish to be. But the efforts of students like Amelia contribute to improving the situation.  Many thanks to Amelia whose commitment helps to make our department better.

Read more about Amelia on the CLAS website. A short summary of her story is in UConn Today.

Astronomers Assemble View of Evolving Universe

 – Donna Weaver & Ray Villard, Space Telescope Science Institute

The University of Connecticut’s Katherine Whitaker is part of a team of astronomers who have put together the largest and most comprehensive “history book” of the universe from 16 years’ worth of observations from NASA’s Hubble Space Telescope.

This image, a mosaic of nearly 7,500 separate Hubble exposures, presents a wide portrait of the distant universe and contains roughly 265,000 galaxies that stretch back through 13.3 billion years of time to just 500 million years after the universe’s birth in the Big Bang. (Space Telescope Science Institute Image)

The deep-sky mosaic provides a wide portrait of the distant universe, containing 200,000 galaxies that stretch back through 13.3 billion years of time to just 500 million years after the Big Bang. The tiny, faint, most distant galaxies in the image are similar to the seedling villages from which today’s great galaxy star-cities grew. The faintest and farthest galaxies are just one ten billionth the brightness of what the human eye can see.

The image yields a huge catalog of distant galaxies. “Such exquisite high-resolution measurements of the legacy field catalog of galaxies enable a wide swath of extragalactic study,” says Whitaker, the catalog lead researcher. “Often, these kinds of surveys have yielded unanticipated discoveries that have had the greatest impact on our understanding of galaxy evolution.”

The ambitious endeavor, called the Hubble Legacy Field, also combines observations taken by several Hubble deep-field surveys, including the eXtreme Deep Field (XDF), the deepest view of the universe. The wavelength range stretches from ultraviolet to near-infrared light, capturing all the features of galaxy ‘assembly over time.

“Now that we have gone wider than in previous surveys, we are harvesting many more distant galaxies in the largest such dataset ever produced,” says Garth Illingworth of the University of California, Santa Cruz, and leader of the team. “This one image contains the full history of the growth of galaxies in the universe, from their times as infants to when they grew into fully-fledged ‘adults.’”

Illingworth says he anticipates that the survey will lead to an even more coherent and in-depth understanding of the universe’s evolution in the coming years.

The deep-sky mosaic provides a wide portrait of the distant universe, containing 200,000 galaxies that stretch back through 13.3 billion years of time to just 500 million years after the Big Bang.

Galaxies trace the expansion of the universe, offering clues to the underlying physics of the cosmos, showing when the chemical elements originated and enabled the conditions that eventually led to the appearance of our solar system and life.

This new wider view contains 100 times as many galaxies as in the previous deep fields. The new portrait, a mosaic of multiple snapshots, covers almost the width of the full Moon, and chronicles the universe’s evolutionary history in one sweeping view. The portrait shows how galaxies change over time, building themselves up to become the giant galaxies seen in the nearby universe. The broad wavelength range covered in the legacy image also shows how galaxy stellar populations look different depending on the color of light.

The legacy field also uncovers a zoo of unusual objects. Many of them are the remnants of galactic “train wrecks,” a time in the early universe when small, young galaxies collided and merged with other galaxies.

Assembling all of the observations was an immense task. The image comprises the collective work of 31 Hubble programs by different teams of astronomers. Hubble has spent more time on this tiny area than on any other region of the sky, totaling more than 250 days.

The image, along with the individual exposures that make up the new view, is available to the worldwide astronomical community through the Mikulski Archive for Space Telescopes (MAST), an online database of astronomical data from Hubble and other NASA missions.

The new set of Hubble images, created from nearly 7,500 individual exposures, is the first in a series of Hubble Legacy Field images. The team is working on a second set of images, totaling more than 5,200 Hubble exposures, in another area of the sky.

In addition, NASA’s upcoming James Webb Space Telescope will allow astronomers to push much deeper into the legacy field to reveal how the infant galaxies actually grew. Webb’s infrared coverage will go beyond the limits of Hubble and Spitzer to help astronomers identify the first galaxies in the universe.

The Hubble Legacy Fields program, supported through AR-13252 and AR-15027, is based on observations made with the NASA/ESA Hubble Space Telescope, obtained at the Space Telescope Science Institute, which is operated by the Association of Universities for Research in Astronomy Inc., under NASA contract NAS 5-26555.

This article first appeared in UConn Today on May 2, 2019.

UConn Astronomers React to First Photo of a Black Hole

credit: Event Horizon Telescope collaboration

This image is the first ever taken of a black hole, captured by the Event Horizon Telescope (EHT) project. The black center is a direct view of the event horizon of a supermassive black hole with a mass of 6.5 billion times the Sun, lying at the center of the Virgo cluster of galaxies. The bright ring is emission from hot gas just above the event horizon, with an asymmetric shape caused by gravitational lensing of light in the strong gravity of the black hole. The EHT collaboration captured the image using a network of 8 radio telescopes that spanned the Earth, effectively creating a planet-sized interferometer.

For more information, see the full NSF press release:

This result directly impacts research in galaxy evolution and cosmology that is being carried out at UConn. The following comments from UConn Astrophysics researchers indicate the level of interest that this result has generated within the international Astrophysics community.

This is a stunning technical achievement. Supermassive black holes are the most extreme objects in the Universe, bizarre rips in spacetime that lie in the center of every massive galaxy. But despite their extreme properties, black holes have a remarkably simple mathematical description, with just a few numbers describing all of their vital properties: mass, size, and spin. Until now, the only way to measure black holes was through indirect methods, like my own research program that uses the timing of light echoes in the surrounding gas. The Event Horizon Telescope black hole image is a tremendous first step in a new understanding of extreme gravity and the detailed astrophysics of black holes. – Jonathan Trump, Assistant Professor
I am fascinated by this result and how we can actually see a direct image of a black hole that is a trillion times our distance to the Sun. This is truly an amazing result for human beings achieved within the limitation of our observational instruments. As an observational astronomer who works with black holes, this result also opens up new possibilities to learn about their unknown features such as black hole spin that could revolutionize our understanding of black hole physics. – Yasaman Homayouni, Graduate Student
This result is a beautiful demonstration of what is possible when the global community works in concert towards a scientific goal. Sometimes the greatest discoveries are not found by the biggest new telescopes in space, but through creative thinking, years of dedicated effort, and big data techniques, building upon what we have here on Earth. – Cara Battersby, Assistant Professor
It is truly extraordinary to be able to provide this new evidence for Einstein’s ideas on space and time through observations made no less than one hundred years since he first proposed them. As to the discovery itself, there are two aspects to black holes, one is that they pull everything in, and the other is that they do not let anything out. With nothing being able to get out, they thus look black to an observer on the outside, to thereby give them their black hole name. Now for many years we have had evidence of things falling into black holes, but had never previously had any evidence that things cannot get out. These new data show a fireball ring of things falling in, with the ring surrounding a black space in the center where nothing can get out. We thus confirm that indeed nothing can escape a black hole. – Philip Mannheim, Professor

For more about this topic, see this recent article in the Daily Campus, UConn Astronomy Community Responds Joyously to M87 Black Hole Image.

Kate Whitaker wins the Sloan Fellowship!

Original UConn Today article here

Rising Star in Astrophysics Receives Sloan Foundation Fellowship

Kate Whitaker, assistant professor of physics, stands next to a telescope inside the observatory on top of the Gant Complex on Feb. 14, 2019. (Peter Morenus/UConn Photo)
Kate Whitaker, assistant professor of physics, stands next to a telescope inside the observatory on top of the Gant Complex on Feb. 14, 2019. (Peter Morenus/UConn Photo)

As an assistant professor of astrophysics, Kate Whitaker spends a lot of her time thinking about stars. Hundreds of billions of stars that comprise galaxies, to be more precise. But with a recent fellowship from the Alfred P. Sloan Foundation, it is Whitaker’s star that is shining brightly.

Whitaker is one of 126 outstanding U.S. and Canadian researchers selected by the Alfred P. Sloan Foundation to receive 2019 Sloan Research Fellowships. The fellowships, awarded yearly since 1955, honor early-career scholars whose achievements mark them as among the most promising researchers in their fields.

Valued not only for their prestige, Sloan Research Fellowships are a highly flexible source of research support. Funds may be spent in any way a Fellow deems will best advance his or her work.

“Sloan Research Fellows are the best young scientists working today,” says Adam F. Falk, president of the Alfred P. Sloan Foundation. “Sloan Fellows stand out for their creativity, for their hard work, for the importance of the issues they tackle, and the energy and innovation with which they tackle them. To be a Sloan Fellow is to be in the vanguard of twenty-first century science.”

According to colleagues, Whitaker certainly fits the bill as one of the brightest young minds at UConn and beyond.

“Kate’s record so far is truly impressive and speaks to her potential as a leader in her field,” explains Barry Wells, head of UConn’s Department of Physics. “It was my great pleasure to nominate her for a Sloan Foundation Research Fellowship, and I am thrilled they felt she was worthy of the prize.”

An observational extragalactic astronomer, Whitaker’s research tries to reveal how galaxies are evolving from the earliest times to the present day.

In addition to her position at UConn, Whitaker is also an associate faculty at the new Cosmic Dawn Center in Copenhagen, Denmark. Whitaker and her students actively collaborate with DAWN, working towards pushing our detection of quiescent “red and dead” galaxies even earlier in time.

She will be among the world’s first scientists to explore the universe using the new James Webb Space Telescope when it is launched in 2019, which she says will allow her to push into new frontiers of research.

Apart from that exciting work, Whitaker and colleagues Cara Battersby and Jonathan Trump were tasked with building a full-fledged astronomy program from scratch at UConn. Not only has their work exceeded expectations, the fruits of their labor are already beginning to emerge. Whitaker and colleagues have so far created five new astrophysics courses with two more slated for next year, established an official astronomy minor, and are operating a thriving research program that involves doctoral students, undergrads, and even local high school students.

“I am both thrilled at this opportunity and humbled to be named amongst such a prestigious cohort of scientists,” says Whitaker. “With the Sloan Foundation’s generous support, I aspire to continue to lead ground-breaking studies of the distant universe, the mystery of which will no doubt captivate our imaginations.”

The Alfred P. Sloan Foundation is a philanthropic, not-for-profit grant making institution based in New York City. Established in 1934 by Alfred Pritchard Sloan Jr., then-President and Chief Executive Officer of the General Motors Corporation, the Foundation makes grants in support of original research and education in science, technology, engineering, mathematics, and economics. A full list of the 2019 Fellows is available at the Sloan Foundation website at https://sloan.org/fellowships/2019-Fellows.

Faculty Profile: UConn Astrophysicist Cara Battersby

Meet the Researcher: UConn Astrophysicist Cara Battersby

UConn astrophysicist, Cara Battersby sits in an office in front of poster of galaxies.

UConn astrophysicist, Cara Battersby. (Carson Stifel/UConn Photo)

A young Cara Battersby once scrawled out the phrase “Science is curious” in a school project about what she wanted to do when she grew up.

This simple phrase still captures Battersby’s outlook on her research about our universe.

Recently shortlisted for the 2018 Nature Research Inspiring Science Award, Battersby has been working on several projects aimed at unfolding some of the most compelling mysteries of galaxies near and far.

“I’m really interested in how stars are born,” Battersby says. “They’re the source of all life on Earth.”

Many of the “laws” we know about how stars are formed are based exclusively on observations of our own galaxy. Because we don’t have as much information about how stars form in other galaxies with different conditions, these laws likely don’t apply as well as we think they should.

Battersby is leading an international team of over 20 scientists to map the center of the Milky Way Galaxy using the Submillimeter Array in Hawaii, in a large survey called CMZoom. She was recently awarded a National Science Foundation grant to follow-up on this survey and create a 3D computer modeled map of the center of the Milky Way Galaxy.

The center of our galaxy has extreme conditions similar to those in other far-off galaxies that are less easily studied, so the Milky Way is an important laboratory for understanding the physics of star formation in extreme conditions.

By mapping out this region in our own galactic backyard, Battersby will be able to form a better idea of how stars form in more remote areas of the universe.

“I love that astrophysics is one of the fields where I can get my hands into everything,” Battersby says. “Stars are something real that you can actually see and study the physics of.”

Battersby is also investigating the “bones” of the Milky Way. Working with researchers from Harvard University, she is looking at how some unusually long clouds could be clues to constructing a more accurate picture of our galaxy.

“Because of the size of our galaxy, it’s infeasible to send a satellite up there to take a picture,” she says.

Since we are living within the Milky Way it is much harder for us to get a clear idea of what it looks like. We know that the Milky Way is a spiral galaxy, but we don’t yet know how many “arms” the spiral has and if it’s even a well-defined spiral.

These kinds of celestial mysteries have long fascinated Battersby.

Battersby says she would “devour” astronomy books and magazines her parents gave her, but it wasn’t until college that her passion truly developed.

She did her Ph.D. thesis at the University of Colorado on high-mass stars being formed on the disk of our galaxy. During this research she made an astounding discovery that every high-density cloud in space is already in some phase of forming a star, a process that takes millions of years.

This led her to conclude that star formation starts as the cloud is collapsing bit by bit, modifying previous ideas of the timeline of this process.

“If you look at something new in a way no one’s looked at it before, the universe has a great way of surprising us,” Battersby says.

View full story on UConn Today.

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By: Anna Zarra Aldrich ’20 (CLAS), Office of the Vice President for Research

 

 

Physics undergrad is the recipient of 2018 Mark Miller research award

Physics major Brenna Robertson has been selected as the recipient of the 2018 Mark Miller Undergraduate Research Award. Brenna’s proposal, which focuses on modeling supermassive black hole spin using spectral emission diagrams, was selected from among a strong pool of applicants. Brenna Robertson is working with Prof. Jonathan Trump.

The Mark Miller Award is a stipend to allow a student to remain in Storrs over the Summer session to work on a research project with a faculty member of the Physics Department. It was created through a donation made by Mark E. Miller, a UConn physics major alum.

NASA awards to two physics undergraduate students

Undergraduate Physics Majors, Sam Cutler and Anthony (Josh) Machado, recently received awards from the NASA Connecticut Space Grant Consortium.

Awards recipients Sam Cutler (right) and Josh Machado

Sam was awarded an Undergraduate Research Fellowship to perform research at UConn this summer working with Prof. Kate Whitaker. The title of his research project is “Examining High Redshift Rotation Curve Outside the Local Universe”.

Josh was awarded the Undergraduate Scholarship by the NASA Connecticut Space Grant Consortium, and will be performing astrophysics research this summer at UConn working with Prof. Cara Battersby.

UConn Prof. Kate Whitaker interviewed by Gizmodo

Gizmodo has recently launched a new series of articles to explore how the best images in science were created and why.  In a recent article in this series by Ryan F. Mandelbaum entitled, “The Making of ‘Pillars of Creation,’ One of the Most Amazing Images of Our Universe”, the author presents a classic set of images taken with the Hubble Space Telescope showing a zoomed-in view of the Eagle Nebula. The article explains some of the details about the instrument that took these images, and how a color image is obtained by combining black-and-white photographs taken at a number of different wavelengths. In the article, UConn astronomer Prof. Kate Whitaker explains why an advanced space-based instrument like the HST is required to obtain awesome views like this of our cosmic neighborhood.

One Giant Leap in Mapping the Universe

An artist’s rendering of hot material falling into a supermassive black hole, creating what is called the accretion disk, shown in orange. Reverberation mapping measures the time it takes light to travel between two areas of the accretion disk. The ‘light echo’ enables direct measurement of the mass of the black hole. This reverberation mapping project is the first project to weigh many black holes at once. (Image by Nahks Tr’Ehnl, Penn State University)

 – Elaina Hancock – UConn Communications

Surveying millions of astronomical objects, such as supermassive black holes, is a huge and time-consuming undertaking. An international team of researchers, including UConn assistant professor and astronomer Jonathan Trump and graduate student Yasuman Homayouni, have been successful in improving and speeding up this complex task of surveying and mapping our skies, in a study published in the Astrophysical Journal.

“In one sentence, it’s a new, industrial-scale way to weigh large numbers of supermassive black holes,” says Trump.

The effort is part of the Sloan Digital Sky Survey, one of the most successful survey projects in the history of astronomy, which has produced the largest and most detailed three-dimensional maps of the Universe to date. Just like early map makers trying to better understand the planet we live on, modern mapping of galaxies, quasars, and supermassive black holes – the largest type of black hole, found in the center of almost all currently known massive galaxies – gives researchers insight into these phenomena and the Universe we live in. The Sloan Digital Sky Survey is creating as detailed a map as possible of a portion of our sky, and has already collected data on more than three million astronomical objects.

Trump and his colleagues are working toward this goal using a method called reverberation mapping on an especially large sample of distant galaxies with supermassive black holes. The technique measures the mass of the black holes by using light echoes of gas orbiting the black holes, far outside the ‘event horizon’ within which nothing can escape falling into the black hole. With this data, he says, black holes can be described very easily.

“Mass is fundamental,” Trump says. “Once you know the mass, you can calculate almost everything there is to know about a black hole.”

It is this ability to understand so much about black holes from knowing just their mass that makes them good mapping targets. Black holes are more than just rips in space and time, and more than vacuum cleaners sucking up everything that gets too close to their event horizons, Trump explains. There are tight connections between black holes and the galaxies they exist in, so knowing the mass of a black hole allows researchers to unlock more information about the galaxy itself. For example, as black hole mass increases, the galaxy’s mass also increases in lockstep. There is also evidence that black holes act as stabilizing forces within their galaxies, and if a black hole happens to be located close to a supernova, the black hole can act to disperse the heavy elements that are created only in these exploding stars throughout the galaxy.

But there is more to learn. “We know black holes are important and they matter for the rest of the Universe, but we still don’t know exactly why,” says Trump. “They are such strange beasts in our reality.”

Speeding up the Mapping Technique

One drawback of reverberation mapping is that it requires multiple observations, over extended periods of time. With so many astronomical objects to observe and only so much equipment capable of taking such detailed measurements, large-scale mapping of this kind has not previously been possible.

“This technique is hard to do,” says Trump. “You need a lot of very well calibrated observations.”

In addition to the sheer number of objects observed for this project, the light signals observed were at times very faint because their sources of emission are at such great distances.

However, this project’s sizable dataset has increased the sample of black holes with reliably known masses by two-thirds in the past year alone – by 44 quasars to be exact. These data are quickly building on decades of existing work that had around 60 well mapped, representing only the last few percent of the history of the Universe.

The reverberation mapping data have reached deeper, around six or seven billion light years away, looking at more distant black holes. And the future of the project will go even farther, Trump says, which will translate to going even farther back in the history of the Universe.

He draws an analogy to periods in a human life to explain the distances in space and time: “We published data on 44 well-characterized black holes at about the middle age of the Universe. We hope to get to 100 [black holes] at around a quarter of the Universe’s age, so equivalent to around its early adolescence or maybe even childhood. A lot of changes happen in adolescence and childhood for us, and the Universe went through a lot of changes at that age too.”

Read more in the Sloan Digital Sky Survey press release here.

This research was supported by funding from the National Science Foundation grant AST-1517113, and Trump’s research group has additional support from the National Aeronautics and Space Administration, NASA HST-GO-15260.