The seven-year photobomb: Distant star’s dimming was likely a ‘dusty’ companion getting in the way, astronomers say

UW doctoral student Anastasios “Andy” Tzanidakis announced the discovery of a rare type of binary star system. Tzanidakis and Dr. James Davenport, a UW research assistant professor of astronomy and associate director of the DiRAC Institute, were investigating why the star Gaia17bpp had gradually brightened over a 2 1/2-year period. In some investigative follow-up work, which involved examining decades of observations of Gaia17bpp, they determined that the star itself was not changing. Instead, according to the data, Gaia17bpp is likely part of a rare type of binary star system, and its apparent brightening was the end a years-long eclipse by a stellar companion that is — quite simply — dusty. Gaia17bpp’s likely companion is slow-moving and surrounded by a disk of unknown material.

Catching this eclipse was a once-in-a-lifetime event, and indicates that this type of system may be more common than previously known. If so, scientists will need to develop theories of how such an unusual stellar pairing arose – because right now, that’s not easy to do.

Here is a link to the full story:

https://www.washington.edu/news/2023/01/10/dusty-binary/

Big Data in the Night Sky

In conversation with James Davenport and 2022 DiRAC Research Prize recipients read more about Vera C. Rubin Observatory and important role of the scientists at the UW’s DiRAC Institute.

Astronomers discover a rare ’black widow’ binary, with the shortest orbit yet

In partnership with the news team at the Massachusetts Institute of Technology, the UW News office has posted a story about a rare and mysterious star system discovered by a team of astronomers and reported in a paper published this morning in Nature. The researchers report that the system appears to be a “black widow binary” — consisting of a rapidly spinning neutron star, or pulsar, that is circling and slowly consuming a smaller companion star, just as its arachnid namesake does to its mate.

UW Space Dialogue with Meredith Rawls

Astronomy, satellites, and the future of our sky

Join us Thursday, May 5th at Noon PDT on Zoom

We are witnessing a new era as skies fill with thousands of low-Earth-orbit satellites that reflect sunlight. Observational astronomy at all wavelengths is increasingly affected, and so is the shared human experience of the night sky. For optical ground-based astronomy, the impacts of satellites are worst for large wide-field facilities. One urgent example is Rubin Observatory in Chile, which will begin a ten-year sky survey in 2024. I will discuss how satellite streaks can impede discovery, and share recent studies that aim to better quantify this. Finally, I will describe the work underway by a dedicated international team to understand, disseminate, and mitigate the impacts across the electromagnetic spectrum for increasingly broad groups of stakeholders.

Bio:
Meredith Rawls is a research scientist in the Department of Astronomy and DiRAC Institute at UW. She writes software and data pipelines to handle terabytes of nightly images from Vera C. Rubin Observatory’s Legacy Survey of Space and Time, which will produce the highest resolution movie of the night sky ever made. Her background is in stellar astrophysics, and she earned her PhD from New Mexico State University. Lately she studies the plethora of newly-launched commercial satellites in the hopes observers worldwide don’t lose the sky. She has served on and chaired working groups and coauthored reports for numerous astronomy workshops on satellite constellations, and she is spearheading the SatHub initiative at the new International Astronomical Union Centre for the Protection of the Dark and Quiet Sky from Satellite Constellation Interference.

NASA releases first image from an in-focus Webb telescope

Distant galaxies come into focus as Webb is on track to meet or exceed expectations. Today, NASA announced that it has successfully completed two further steps to align the mirrors of the Webb telescope. The resulting performance indicates that Webb will meet or exceed its design goals.

Hubble telescope spots a ‘Space Triangle’ galaxy crash with ‘tsunami of starbirth’

“Part of the reason for that shape is that these galaxies are still so close to each other, and NGC 2444 is still holding on to the other galaxy gravitationally,” participating astronomer Julianne Dalcanton, of the Flatiron Institute’s Center for Computational Astrophysics in New York and the University of Washington in Seattle, said in the Hubble statement.