Letter From the Director

Welcome to the DiRAC Institute Spring newsletter!

As we’re nearing the close of this academic year, I’m excited to share with you some of the work, discoveries, teaching and mentoring initiatives started at DiRAC over the past months.

Today, the New York Times features the discovery of 104 asteroids by the Asteroid Institute, using the THOR algorithm running on the Asteroid Discovery Analysis and Mapping (ADAM) cloud-based astrodynamics platform! This groundbreaking computational technique running ADAM not only allows us to discover and track asteroids in historical data sets, but will change the way we do asteroid discovery in the future.  

We would like to announce the DiRAC Research Prize for Undergraduate Research, a new paid summer research opportunity for UW undergraduates. This program will enable UW students to spend a quarter with DiRAC researchers working on data-intensive problems across all areas of astrophysics. Such hands-on experiences offer opportunities to further develop research skills and understand how research works in practice from idea to an academic poster or paper. This Prize was made possible by generous funding received from DiRAC Husky Giving Day 2022 supporters and the DiRAC Advisory Board.

Beyond the Prize, we are also happy to be supporting the return to in-person of “Astronomy on Tap” — a UW graduate-student driven outreach program — and share a few research highlights from the multitude of amazing research at the Institute: from discovering rare “black widow” binary star, protecting the view of the heavens from satellite constellations, to supernova siblings discovered in the ZTF survey.

These are just some of the many accomplishments our researchers made in a year still marked by the lingering impacts of the pandemic. I am extremely proud by how all of us — our staff, our undergraduate and graduate students, postdocs, researchers, engineers and faculty — who continue to be supportive and caring for each other, while expanding the boundaries of science.

Thank you,

Mario Jurić

Director, DiRAC Institute
Professor, Department of Astronomy

New Summer Research Prize for UW Students

We are pleased to officially announce our new Summer Research Prize for UW undergrads!

This program will award $3500 to UW undergrads working on summer projects with researchers in the DiRAC Institute (note: we especially welcome projects w/ collaborative mentors across the department!). 

Thanks to the generous support from the Advisory Board members and the community during Husky Giving Day, we expect to award 5 of these prizes this summer.

The application form is simple, and can be turned in via email to jrad@uw.edu. Selections will be made before the end of Spring Quarter. Prize winners will give a brief seminar at the end of the Summer or early Fall to showcase their projects, which the entire department will be invited to.

University of Washington

Astronomy on Tap is Back

After a long time, and many breaks, hiatuses, and Astronomy’s at Home, for the first time in two years AoT is back in person! It resumed in February and be sure to follow them on Twitter and Facebook to get updates on future events or watch past events on their YouTube channel.

Each FREE Astronomy on Tap event features accessible, engaging science presentations on topics ranging from planets to black holes to the beginning of the Universe. Most events have games and prizes to test and reward your new-found knowledge! There is always lots of time to ask questions and interact with the presenters and other scientists who inevitably stick around for the beer.

Supernova Siblings and their Parent Galaxies in the ZTF Bright Transient Survey

Supernovae are the explosions of stars that can be seen across vast distances, appearing as new bright points of light in optical images of the sky, even when the original star was far too faint to be detected.

When different types of stars explode (e.g., low-mass and high-mass) they cause supernovae with a variety of characteristics (e.g., brightness, color, duration). When two or more supernovae (explosions of stars) occur in the same galaxy, we say they have the same “parent galaxy” and are “sibling supernovae”. The characteristics of sibling supernovae can thus be compared knowing that, since they have the same distance from Earth and come from similar environments, any differences between them are more likely to be related to the type of star that exploded. Sibling supernovae are thus very useful for obtaining a better understanding of both supernovae and their parent galaxies.

“An image of the grand design spiral galaxy Messier 100, which has parented at least seven sibling supernovae in the past century (that we know of!). This image was obtained through the g filter by the PanSTARRS survey, and siblings 2019ehk and 2020oi were discovered by ZTF.”

Since the average supernova rate for a Milky Way-type galaxy is just one per century, a large imaging survey is required to discover an appreciable sample of sibling supernovae. In this paper we present 10 sibling supernovae in 5 parent galaxies from the wide-field Zwicky Transient Facility (ZTF).

For each of these families we analyze the supernova’s location within the parent galaxy, finding agreement with expectations that supernovae from more massive stars are found nearer to their parent galaxy’s core, and in regions of more active star formation.

We also present an analysis of the relative rates of core collapse and thermonuclear sibling supernovae, finding a significantly lower ratio than past samples due to the unbiased nature of the ZTF.

Published paper by Melissa Graham

ADS: Supernova Siblings and their Parent Galaxies in the Zwicky Transient Facility Bright Transient Survey

About

Melissa Graham currently works for Rubin Observatory as the Lead Community Scientist for the Community Engagement Team and as a Science Analyst for the Data Management team. Her main research focus is supernovae, especially those of Type Ia.

Astronomers Discover a Rare ’Black Widow’ Binary, With the Shortest Orbit Yet

The flashing of a nearby star drew the attention of a team of astronomers, who discovered that it is part of a rare and mysterious system. As they report in a paper published May 4 in Nature, the stellar oddity appears to be a “black widow binary” — a type of system consisting of a rapidly spinning neutron star, or pulsar, that is circling and slowly consuming a smaller companion star, as its arachnid namesake does to its mate.

The team, led by co-author Kevin Burdge, a postdoctoral researcher at the Massachusetts Institute of Technology, found the black widow binary utilizing data from the Zwicky Transient Facility, a California-based observatory that takes wide-field images of the night sky.

“This discovery highlights the potential of large time-domain surveys like ZTF to find rare astrophysical objects,” said co-author Eric Bellm, a research assistant professor of astronomy at the University of Washington, fellow at the UW’s DiRAC Institute and scientist with both the ZTF and the Chile-based Vera C. Rubin Observatory.

Read full UW Press Release here.

An illustrated view of a black widow pulsar and its stellar companion. The pulsar’s gamma-ray emissions (magenta) strongly heat the facing side of the star (orange). The pulsar is gradually evaporating its partner.NASA/Goddard Space Flight Center/Cruz deWilde

Heavens Need Environmental Protection Just Like Earth, Experts Say

Space urgently needs special legal protection similar to that given to land, sea and atmosphere to protect its fragile environment, argues a team of scientists. The scientific, economic and cultural benefits of space should be considered against the damaging environmental impacts posed by an influx of space debris — roughly 60 miles above Earth’s surface — fueled by the rapid growth of so-called satellite mega-constellations.

In a paper published April 22 in Nature Astronomy, the authors assert that space is an important environment to preserve on behalf of professional astronomers, amateur stargazers and Indigenous peoples.

“We need all hands on deck to address the rapidly changing satellite situation if we can hope to co-create a future with dark and quiet skies for everyone,” said co-author Meredith Rawls, a research scientist with the Vera C. Rubin Observatory and the University of Washington’s Data Intensive Research in Astrophysics and Cosmology Institute, or DiRAC Institute.

Read UW News article in full here.

Starlink satellites over the Carson National Forest in New Mexico, photographed shortly after launch.M. Lewinsky