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.
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.
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.
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.”
[The] James Webb [Space Telescope] will begin teaching us entirely new things … things we don’t even know about. — Jonathan Trump
Just like the highly anticipated release of a new phone, game, or gadget, astrophysicists worldwide are eager to start using the new telescope, the latest technology for viewing distant elements of our universe, which is currently set to launch in 2019. But rather than stand in line for hours outside a store, researchers had to submit compelling proposals to secure their spot in line and an opportunity to use the new technology.
The highly competitive, peer-reviewed James Webb Space Telescope Early Release Scienceprogram was created to test the capabilities of the new observatory and to showcase the tools the telescope is equipped with. Of more than 100 proposals submitted, only 13 were chosen to participate in the early release phase, including two separate proposals involving UConn researchers Kate Whitaker and Jonathan Trump, both assistant professors of physics.
Passing the Telescope Torch
The James Webb Space Telescope, designed to be a large space-based observatory optimized for infrared wavelengths, will be the successor to the Hubble Space Telescope. The Hubble telescope has been a versatile workhorse and vital tool since its launch in 1990, allowing researchers to peer deep into space and get crisp glimpses of distant galaxies.
But it has technological limitations, and is not currently scheduled for any upgrades or servicing. Since its last service in 2009, Whitaker says, many researchers have been keeping their fingers crossed that it would continue functioning. Hubble is currently the only way to make observations that are required for the type of research she and many others conduct.
“A lot of my research right now is pushing Hubble to its limits,” she notes. “It’s an exciting time, because with the capabilities of the James Webb Space Telescope, we will really push into the frontiers of research.”
The James Webb Space telescope is equipped with tools that will surpass Hubble’s capabilities. Webb will be launched further into space and will be capable of powerful imaging that will produce sharper images and be able to capture images into the infrared range.
Peering into the infrared range allows researchers to observe signatures, in the form of light, from events that happened long ago. The universe is constantly expanding and as light travels, it gets stretched over time, Whitaker explains. The further back you go, say a few billion years or so, the light is stretched so much that it will shift from the visible region of the spectrum into the infra-red.
“Since we cannot travel to these distant galaxies, all we can do is sit here and wait for their light to reach our telescopes,” says Whitaker.
Trump is a co-investigator on the proposal called “CEERS: The Cosmic Evolution Early Release Science Survey,” a plan to conduct an extragalactic survey in hopes of gaining insights into the formation of the first galaxies following the big bang. They plan to look at aspects of the assembly of galaxies, including their number density, chemical abundance, star formation, and the growth of supermassive black holes.
“Hubble has totally transformed our view of the universe and James Webb will begin teaching us entirely new things,” Trump says. “I’m incredibly excited to think about all of the things we don’t even know about, that James Webb will begin to tell us.”
The Early Release Program is aimed not only to showcase the capabilities of the James Webb Space Telescope right away, but to make the data publicly available as soon as possible. It is anticipated that the data will facilitate huge breakthroughs in research.
Stay tuned: 2019 promises to be an exciting year in astrophysics.
For the first time, scientists have directly detected gravitational waves — ripples in space-time — in addition to light from the spectacular collision of two neutron stars. This marks the first time that a cosmic event has been viewed in both gravitational waves and light.
The discovery was made using the U.S.-based Laser Interferometer Gravitational-Wave Observatory (LIGO); the Europe-based Virgo detector; and some 70 ground- and space-based observatories.
Neutron stars are the smallest, densest stars known to exist and are formed when massive stars explode in supernovas. As these neutron stars spiraled together, they emitted gravitational waves that were detectable for about 100 seconds; when they collided, a flash of light in the form of gamma rays was emitted and seen on Earth about two seconds after the gravitational waves. In the days and weeks following the smashup, other forms of light, or electromagnetic radiation — including X-ray, ultraviolet, optical, infrared, and radio waves — were detected.
GW170817: A Global Astronomy Event
The observations have given astronomers an unprecedented opportunity to probe a collision of two neutron stars. For example, observations made by the U.S. Gemini Observatory, the European Very Large Telescope, and the Hubble Space Telescope reveal signatures of recently synthesized material, including gold and platinum, solving a decades-long mystery of where about half of all elements heavier than iron are produced.
The LIGO-Virgo results are published today in the journal Physical Review Letters; additional papers from the LIGO and Virgo collaborations and the astronomical community have been either submitted or accepted for publication in various journals.
“It is tremendously exciting to experience a rare event that transforms our understanding of the workings of the universe,” says France A. Córdova, director of the National Science Foundation (NSF), which funds LIGO. “This discovery realizes a long-standing goal many of us have had, that is, to simultaneously observe rare cosmic events using both traditional as well as gravitational-wave observatories. Only through NSF’s four-decade investment in gravitational-wave observatories, coupled with telescopes that observe from radio to gamma-ray wavelengths, are we able to expand our opportunities to detect new cosmic phenomena and piece together a fresh narrative of the physics of stars in their death throes.”
On Monday, August 21, 2017, the moon eclipsed the sun across the US. What began as a small organic outreach activity blossomed into an epic community event. With help from UConn communications, the UConn Physics club, and staff in the physics department, astronomers Jonathan Trump, Cara Battersby, and Kate Whitaker hosted an eclipse viewing event open to the public. Solar projectors, solar glasses, and solar telescope drew and estimated 2,000 visitors, including many children and families to share in the majesty of the heavens. To read more about the great American eclipse, read the recent UConn Today article by Elaina Hancock, featuring commentary by astronomers Trump and Cynthia Peterson.
For more about the event and others around the state, see this article in the Hartford Courant
Please join the Department of Physics at UConn for a Solar Eclipse Viewing Party!
Hosted by Prof. Cara Battersby, Prof. Jonathan Trump, and Prof. Kate Whitaker
August 21 2017, Horsebarn Hill 1:00 – 4:00 PM (next to Dairy Bar) weather permitting
From our location, the solar eclipse begins at 1:25pm and ends at 4:00pm. Maximum (partial) occultation occurs at 2:45pm.
The organizers have 150 solar eclipse glasses available on a first-come, first-serve basis (encouraging folks to recycle them when they are
done). No reservations are necessary. Here is the schedule of the events:
2:00pm Short Tutorial on Eclipses
2:45pm Maximum (partial) occultation
3:15pm Ask an Astrophysicist
There will be also an ongoing activity from 1-4pm making pin-hole cameras (great for kids!), while supplies last. Finally, there will be 4 solar
telescopes set up for the entire event.
All ages are welcome!
Join our mailing list for updates: http://tinyurl.com/uconn-astro-mailing-list
A spectacular and likely unforgettable show will take place in the sky Aug. 21.
“Have you ever seen a total solar eclipse?” asks Cynthia Peterson, professor emerita of physics. “It’s a really, really exciting event!”
The reason she and so many others are excited for this event has a lot to do with its rarity. The last time a total solar eclipse was visible from the mainland United States was 38 years ago, in February 1979.
Very specific conditions have to be met to create an eclipse that can be viewed from Earth. The Earth and the moon must align perfectly with the sun as they speed through space, an amazing coincidence. To fully understand how this happens, Peterson says, it’s helpful to know some basic astronomy.
Conditions for a Total Solar Eclipse
The Earth moves in space around the sun, completing a full orbit once every 365.25 days, she explains. As the Earth and other members of our solar system travel around the sun, they continue in essentially the same plane, on a path called the ecliptic. Some celestial bodies, such as our moon, deviate from the ecliptic slightly.
The orbit of the moon is inclined on the ecliptic plane at an inclination of 5 degrees. As the moon deviates 5 degrees above or below the ecliptic plane, it will cross the plane at points called nodes.
“That is the first essential piece of the eclipse puzzle,” says Peterson. “The moon must be at a node for an eclipse to occur. Otherwise, the moon will not align and no eclipse will be seen from Earth.”
The moon’s position in the lunar cycle is another vital eclipse component. As the Earth travels in its orbit, the moon tags along, keeping its gaze locked on Earth, always facing from the same side as it completes its own orbit around Earth once every 29.5 days. Over the course of a month, the moon’s appearance changes, from crescent to full to crescent again and finally to what appears to be its absence, when it’s called a new moon. A new moon is the other requirement for a solar eclipse.
“The basic rule for a solar eclipse is to have a new moon at a node,” Peterson points out.
But during an eclipse, how can our moon, which is relatively small, appear almost as big as the sun, which is pretty gigantic?
Peterson explains, “The sun is 400 times bigger than the moon and the sun is also 400 times farther away from the moon, so the moon appears to fit exactly during an eclipse, when they are both the same angular size.”
Holding up her fist, she demonstrates: “Find a large object ahead of you and pretend it is the sun and your fist is the moon. If you hold up your fist and look with one eye, you can’t see the object/sun.”
These are the conditions for a total solar eclipse like the one coming up. “Solar eclipses happen when the new moon obstructs the sun and the moon’s shadow falls on the earth, creating a total solar eclipse.” Peterson moves her fist slightly away from herself until the edges of the object can be seen around it. “Or, when the moon covers the Sun’s center and creates a ‘ring of fire’ around the moon, it’s what’s called an annular eclipse.”
It’s those bits of the sun peeking out from behind the moon – in both partial and total eclipses – that everyone needs to be careful of. It’s extremely important to view the eclipse safely, Peterson stresses. “The problem with the eclipse is that every time it happens, some people are blinded [from looking at it unprotected]. The shadow goes whipping by at 1,000 miles per hour, and you never want to stare at the sun, even a sliver of it.”
So be prepared, and ensure you wear proper solar eclipse eye protection. Regular sunglasses will not help. Solar eclipse glasses can be used, welder’s goggles, or telescopes with proper lenses. Be sure the eye protection you choose is certified by the International Organization for Standardization (ISO). Other popular viewing methods are DIY viewing boxes like these.
Peterson, like many others who wish to get the full eclipse experience, will be traveling to an area directly in the path of the eclipse’s shadow. These areas are called totality. The Aug. 21 eclipse will cover an expansive area of totality that will include 14 states and 14 major U.S. cities, stretching from Lincoln Beach, Oregon to Charleston, South Carolina. For a map of the path of totality, go to the NASA website. Connecticut is unfortunately hours of travel from the nearest totality. Peterson will go as far as Nebraska for the experience.
“You’ll only see a partial eclipse here in Connecticut,” she says. “It will get a little darker, like a cloud covering part of the sun, and then brighten up again.”
She encourages those who can to try to travel to a viewing point for the total eclipse, where they may see “amazing phenomena” like the diamond ring, shadowbands, crescent-shaped solar images under trees (instead of the usual ‘coins’ which are pinhole images of the sun), and extremely sharp shadows in the final minute before totality, due to the very narrow sun at that time. “These phenomena can only be seen in totality,” she says.
The next chance to see a total solar eclipse will be in 2024, when its shadow will be cast closer to Connecticut. It will start in the U.S. in Texas, then make its way north, through northern Vermont and New Hampshire.
“That’s less than seven years from now,” Peterson points out, “but that’s the end of eclipses crossing the U.S. until the 2050s.”
For those on campus next week, you aren’t out of luck. For this eclipse there will be a viewing party on Horsebarn Hill behind the Dairy Bar, from 1 to 4 p.m., hosted by the Department of Physics. “We’ll have solar telescopes, a pinhole camera activity, and will do some short mini-lectures on astronomy at UConn and about how eclipses work,” says Assistant Professor of Physics Jonathan Trump, one of the faculty members who will lead the viewing party.
Peterson, longtime astronomer and scientist, says witnessing an eclipse – especially a total eclipse – can be extremely emotional. She suggests reading Annie Dillard’s essay about solar eclipses, where the author compares the contrast between viewing a partial eclipse and viewing a total eclipse to the difference between flying in an airplane versus falling out of the airplane. “Those are very different experiences.”
But wherever you are on the afternoon of Aug. 21, Peterson says, stop and enjoy the show: “Good luck and clear skies!”
The eclipse will be live-streamed by NASA, and can also be viewed on PBS’ NOVA at 9 p.m. on Aug. 21.
The Physics department is pleased to announce a new thrust in research, scholarship and teaching with the hire of three young astronomers:
Jonathan Trump arrives from a Hubble Space Telescope Fellowship at Penn State University, Cara Battersby who currently has an NSF fellowship at the Harvard Smithsonian Center for Astrophysics and Katherine Whitaker Tease who is currently completing a Hubble Space Telescope Fellowship at UMass. Both Kate and Cara will take a one-year leave to finish their current appointments and they will be on campus full time starting Fall 2017.