Tag: cosmology
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Was the Big Bang actually the beginning?
I usually avoid the kinds of sexy big questions that often make cosmology books by Paul Davies or Stephen Hawking or Roger Penrose popular. The main reason for that is because those big questions may not be answerable, because they are beyond the reach of our telescopes or experiments. One such question—what, if anything, came…
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Green Peas were all my joy, galaxies were my delight
Most galaxies are somewhat red or blue in appearance, depending on the populations of stars that comprise them. However, citizen scientists working with the GalaxyZoo project identified a previously unknown type of galaxy: Green Peas, so named because they are small and green. The color comes from ionized oxygen, a particular form of emission that…
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Death of a white dwarf, 10 billion years later
White dwarfs are the remnants of the cores of stars like our Sun. They have the mass of a star packed into the volume of Earth, but when they die, their light can be detected across the observable Universe. Researchers using the Hubble Space Telescope identified the farthest white dwarf supernova yet seen, one which…
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Learn cosmology with me and Ryan Gosling
OK, one part of that title isn’t true, unless Ryan Gosling signs up for the class in the next few days. There are still spots in my new online class “The Universe in a Box”, beginning next Tuesday, April 2. Sign up today! Also, we’re beginning another new class at CosmoAcademy: “The Sun and Stellar…
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Planck: news from the infant Universe
For cosmology-lovers like me, yesterday was a full, busy day. The Planck telescope released its first full set of data, refining the estimates of the age of the Universe and its contents. I wrote two big pieces, one for Ars Technica and one for Galileo’s Pendulum. First Planck results: the Universe is still weird and…
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In which I get a little fanboyish about ALMA
I’m a theoretical physicist by training and inclination, but I’m not immune to awesome experiments or observatories. (Ahem.) Case in point: the new Atacama Large Millimeter/submillimeter Array (ALMA) in Chile. This array of 66 telescopes in the high Atacama Desert is particularly well suited to hunt for the earliest galaxies and stars in the Universe.…
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Aging binaries provide new calibration for cosmic distances
Cosmology—the study of the Universe as a whole—requires accurate measurements of the distances to galaxies and other objects billions of light-years away. However, the reliability of those estimates depends on how accurately we know the distance to closer objects, such as the Milky Way’s satellite galaxy known as the Large Magellanic Cloud (LMC). A new…
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Will we ever know the identity of dark matter?
Forgive me if I get excited for a moment, but…today marks my first contribution to BBC Future! The feature I contributed is part of the “Will we ever?” series, in which science writers ask some big questions about what research may or may not be able to answer in the future. My article pondered whether…
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“A” is for axion
Originally posted on Galileo's Pendulum: Wot’s all this, now? Today I begin a new feature, which I will try to update once a week: the Alphabet of Cosmology. In these entries, I’ll highlight a concept, experiment, or observation in cosmology—the study of the history, contents, and evolution of the Universe—that may not be as…
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A drink from the cosmic cellar shows that some things never change
Certain physical quantities—the fundamental electric charge, the masses of certain particles, the strengths of the basic forces of the Universe—are generally assumed to be constant in time and space. Some of our theories depend on that constancy, but it’s not an absolute certainty: it’s possible that in distant galaxies, the rules might be a little…
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