![]() ![]() Elizabeth first got interested in space after watching the movie Apollo 13 in 1996, and still wants to be an astronaut someday. Elizabeth is also a post-secondary instructor in communications and science at several institutions since 2015 her experience includes developing and teaching an astronomy course at Canada's Algonquin College (with Indigenous content as well) to more than 1,000 students since 2020. in Space Studies from the University of North Dakota, a Bachelor of Journalism from Canada's Carleton University and a Bachelor of History from Canada's Athabasca University. Her latest book, " Why Am I Taller?", is co-written with astronaut Dave Williams. ![]() ![]() Elizabeth's reporting includes multiple exclusives with the White House and Office of the Vice-President of the United States, an exclusive conversation with aspiring space tourist (and NSYNC bassist) Lance Bass, speaking several times with the International Space Station, witnessing five human spaceflight launches on two continents, working inside a spacesuit, and participating in a simulated Mars mission. She was contributing writer for for 10 years before joining full-time. Together with the bounds found for stellar-mass black holes and the M87 black hole, our observations provide further support that the external spacetimes of all black holes are described by the Kerr metric, independent of their mass.Elizabeth Howell (she/her), Ph.D., is a staff writer in the spaceflight channel since 2022 covering diversity, education and gaming as well. We compare our results to the broader landscape of gravitational tests. Date: ApPrimary Reference: The Event Horizon Telescope Collaboration, et al. Using the observed image size and the broadband spectrum of Sgr A*, we conclude that a thermal surface can be ruled out and a fully reflective one is unlikely. 4 years ago README.md First M87 EHT Results: Calibrated Data Authors: The Event Horizon Telescope Collaboration et al. When surrounded by a transparent emission region, black holes are expected to reveal a dark shadow caused by gravitational light bending and photon capture. 130 The EHT images of M87's core at 230 GHz (1.3 mm wavelength) revealed a ring-like structure whose diameter. To consider alternatives to the presence of an event horizon, we explore the possibility that Sgr A* is a compact object with a surface that either absorbs and thermally reemits incident radiation or partially reflects it. The Event Horizon Telescope (EHT) Collaboration has recently reported the first images of the event-horizon-scale structure around the supermassive black hole in the core of the massive elliptical galaxy M87, one of its two main targets. We use these bounds to constrain metrics that are parametrically different from Kerr, as well as the charges of several known spacetimes. Analogue signals collected by the antenna are converted to digital signals and stored on hard drives together with the time signals provided by the atomic clock. Each antenna, spread out over vast distances, has an extremely precise atomic clock. We use the exquisite prior constraints on the mass-to-distance ratio for Sgr A* to show that the observed image size is within ~10% of the Kerr predictions. A schematic diagram of the VLBI mechanism of EHT. We calibrate the relationship between the geometrically defined black hole shadow and the observed size of the ring-like images using a library that includes both Kerr and non-Kerr simulations. We present new constraints on potential deviations from the Kerr prediction based on 2017 EHT observations of Sagittarius A* (Sgr A*). This is the only stationary, vacuum, axisymmetric metric, without electromagnetic charge, that satisfies Einstein's equations and does not have pathologies outside of the event horizon. Astrophysical black holes are expected to be described by the Kerr metric. ![]()
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