Asteroids in the inner solar system

July 1, 2021 | Physics Today

Observations and computer simulations of their orbits and interactions with planets yield insights into the asteroids’ dynamic lives. Sarah Greenstreet is a senior researcher with the B612 Asteroid Institute in Mill Valley, California, and a research scientist with the Dirac Institute at the University of Washington in Seattle.

Read More »

Astronomers Thrill at Giant Comet Flying into Our Solar System

June 30, 2021 | Jonathan O’Callaghan

In October 2023 a new telescope in Chile called the Vera C. Rubin Observatory will begin a 10-year survey of the entire overhead sky called the Legacy Survey of Space and Time (LSST). “Typical telescopes find objects out to 50 or 60 AU,” says LSST team member Mario Jurić of the University of Washington. “With LSST, we […]

Read More »

Astronomers Document the Rise and Fall of a Rarely Observed Stellar Dance

January 14, 2021 | James Urton | UW News

A team led by Dr. James Davenport, research assistant professor of astronomy at the UW and associate director of the UW’s DIRAC Institute, analyzed more than 125 years of observations of HS Hydra – from astro-photographic plates in the late 1800s to 2019 observations by TESS – and showed how this system has changed dramatically over the course of just a few generations.

Read More »

Photometric Redshifts with the LSST II: The Impact of Near-Infrared and Near-Ultraviolet Photometry

April 23, 2020 | DiRAC News

Published paper includes contribution from DiRAC Researchers: Graham Melissa, Connolly Andrew, Morrison Christopher B., Ivezić Željko, Daniel Scott, Jones R. Lynne, Jurić Mario, Yoachim Peter, Bryce Kalmbach J. Published Date: April 2020. Abstract Accurate photometric redshift (photo-zz) estimates are essential to the cosmological science goals of the Vera C. Rubin Observatory Legacy Survey of Space and […]

Read More »

Photometric Biases in Modern Surveys

March 30, 2020 | DiRAC News

Dr. Stephen Portillo, DiRAC Postdoctoral Fellow, coauthored paper “Photometric Biases in Modern Surveys” published in March 2020. Many surveys use maximum-likelihood (ML) methods to fit models when extracting photometry from images. We show that these ML estimators systematically overestimate the flux as a function of the signal-to-noise ratio and the number of model parameters involved in the […]

Read More »

Orbital Dynamics of 2020 AV2: the First Vatira Asteroid

February 25, 2020 | Physics Today

Paper published by DiRAC Researcher, Dr. Sarah Greenstreet. Dr. Greenstreet is a joint postdoctoral fellow with the Asteroid Institute, a program of B612, and the DiRAC Institute at the University of Washington. Her research interests include the study of orbital dynamics and impacts of small bodies in the Solar System.

Read More »

Insights from MU69’s (Lack of) Craters

May 17, 2019 | AAS NOVA

Months ago, a team of scientists led by Sarah Greenstreet (B612 Asteroid Institute and University of Washington) conducted a study in which they made predictions for the crater count they expected to find on MU69’s surface. Greenstreet and collaborators used observations of Pluto and Charon’s surfaces and models of known Kuiper-belt populations to explore the […]

Read More »

Patient Astronomers Catch Stellar Litterbugs

January 9, 2019 | UW News

Dr. Melissa L. Graham, LSST Research Scientist and DiRAC Fellow, coauthored paper on a large Hubble survey of supernovae “Delayed Circumstellar Interaction for Type Ia SN 2015cp Revealed by an HST Ultraviolet Imaging Survey”. Read UW Press Release Here Read a related story in GeekWire

Read More »