You’ve probably heard of a blue moon – a second full moon in a calendar month – but have you ever heard of a blue star? During wartime, they signify having a family member in the service, but in astronomy they’re extremely rare giant hot stars that are extremely short-lived. That makes a new discovery. Read more »
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Research from Penn’s Department of Physics and Astronomy has produced the largest catalog of galaxy morphology classification to date. Led by former postdocs Jesús Vega-Ferrero and Helena Domínguez Sánchez, who worked with professor Mariangela Bernardi, this catalog of 27 million galaxy morphologies provides key insights into the evolution of the universe. The study was published in
The researchers used data from the Dark Energy Survey (DES), an international research program whose goal is to image one-eighth of the sky to better understand dark energy’s role in the accelerating expansion of the universe.
A byproduct of this survey is that the DES data contains many more images of distant galaxies than other surveys to date. “The DES images show us what galaxies looked like more than 6 billion years ago,” says Bernardi.
Newly Discovered Region of The Milky Way Is Filled With Stars Ready to Blow Up
BEN TURNER, LIVE SCIENCE
9 APRIL 2021
Astrophysicists have found a new region of the Milky Way, and it s filled with searingly hot, bright-blue stars that are about to explode.
The researchers were creating the most detailed map yet of the star-flecked spiral arms of our galactic neighborhood with the European Space Agency s (ESA) Gaia telescope when they discovered the region, which they have named the Cepheus spur, they reported in a new study.
Nestled between the Orion Arm – where our solar system is – and the constellation Perseus, the spur is a belt between two spiral arms filled with enormous stars three times the size of the sun and colored blue by their blistering heat.
“Astronomers – and casual viewers of the night sky – must expect a future in which the low Earth orbit population includes tens of thousands of relatively large satellites,” Jonathan McDowell at the Harvard-Smithsonian Center for Astrophysics warned in a 2020 study. “The impacts will be significant for certain types of observation, certain observatories and at certain times of year.”
Until a couple years ago, humanity had launched fewer than 10,000 objects into orbit since the start of the Space Age. However, with the advent of low-cost commercial rocket launch technology which has seen the price per pound of launching cargo fall from $24,800 during the Shuttle era to just $1,240 today the rate at which we put satellites into orbit is set to increase exponentially.
A time exposure captures trails left by Starlink internet relay satellites after their release into low-Earth orbit last year. Image: Andreas Möller
New research indicates rapidly growing numbers of satellites, so called “mega constellations” devoted to space-based internet and other commercial services, are generating more overall light pollution, or skyglow, than previously understood.
An analysis in
Monthly Notices of the Royal Astronomical Society: Letters concludes the overall brightness of the night sky could increase by more than 10 percent across a large part of the planet.
“Our primary motivation was to estimate the potential contribution to night sky brightness from external sources, such as space objects in Earth’s orbit,” said Miroslav Kocifaj of the Slovak Academy of Sciences and Comenius University in Slovakia, who led the study.