NASA Provides a Timelapse Movie Showing How the Universe Changed Over 12 Years

This mosaic is composed of images covering the entire sky, taken by the Wide-field Infrared Survey Explorer (WISE) as part of WISE’s 2012 All-Sky Data Release. By observing the entire sky, WISE can search for faint objects, like distant galaxies, or survey groups of cosmic objects. Credits: NASA/JPL-Caltech/UCLA

The Universe is over 13 billion years old, so a 12-year slice of that time might seem uneventful. But a timelapse movie from NASA shows how much can change in just over a decade. Stars pulse, asteroids follow their trajectories, and distant black holes flare as they pull gas and dust toward themselves.

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Webb Scans a Nearby Brown Dwarf and Finds it has Clouds Made of Sand

An artist's conception of a brown dwarf. A new study identifies CK Vulpeculae as the remnant of a collison between a brown dwarf and a white dwarf. Image: By NASA/JPL-Caltech (http://planetquest.jpl.nasa.gov/image/114) [Public domain], via Wikimedia Commons
An artist's conception of a brown dwarf. A new study identifies CK Vulpeculae as the remnant of a collison between a brown dwarf and a white dwarf. Image: By NASA/JPL-Caltech (http://planetquest.jpl.nasa.gov/image/114) [Public domain], via Wikimedia Commons

In its first few months of operation, the James Webb Space Telescope (JWST) is already proving that it was well worth the wait! To date, it has provided astronomers with the most detailed and precise images of the cosmos, conducted observations of iconic galaxies and nebulae, peered to the very edge of the Universe, and obtained spectra from distant exoplanets. These resulting images, made public through the JWST Early Release Science (ERS) program, have provided a good cross-section of what this next-generation observatory can do.

Among its many objectives, the JWST will provide valuable insights into the formation and evolution of exoplanet systems through direct imaging. Using data from the ERS, an international team of astronomers and astrophysicists conducted a direct imaging study of a brown dwarf companion (VHS 1256-1257 b) orbiting within a triple brown dwarf system approximately 69.0 light-years away. The spectra they obtained from this body provided a detailed composition of its atmosphere, which included an unexpected find – clouds made of silicate minerals (aka. sand)!

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A New Technique Finds a Bundle of Brown Dwarfs

brown dwarf artist's concept
An artist's conception of a T-dwarf brown dwarf object. Credit: Robert Hurt.

Astronomers have a brown dwarf problem. They should be seeing a lot more of these objects, which are cooler than stars but hotter than planets. Yet, there have only been about 40 directly imaged over the past few decades. Why aren’t astronomers finding more of them? It helps to remember that brown dwarfs are dim, low-temperature objects. They don’t stand out in a crowded starfield. If they’re too close to their stars, the starlight hides them from our view. They’re much better observed in the infrared part of the electromagnetic spectrum. All these characteristics make hunting for them difficult.

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Twin Brown Dwarfs Discovered, Orbiting one Another at Three Times the Distance From the Sun to Pluto

Gravity is a funny force.  The gravity of every given object technically impacts every other given object, though, in practice, large distance and small masses make those forces negligible for such interactions.  But in some cases, especially when large groups are floating in empty space, gravity can still hold sway over considerable distances.  Such is the case with a new pair of brown dwarfs found by astronomers at the Keck Observatory.

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Brown Dwarfs are Probably Much More Common in the Milky Way Than Previously Believed

Brown dwarfs are too big to be planets, but not quite massive enough to be stars. Credit: NASA/JPL-Caltech

Brown dwarfs are strange things. They are in the middle ground between planets and stars. A star is defined as an object massive enough for hydrogen to fuse into helium into its core, while a planet is too small for core fusion to occur. It seems a simple distinction until you learn about fusion. Anything with a mass below about 13 Jupiters is too small for fusion to occur, and is thus a planet. If your mass is about about 80 Jupiters, then you can fuse helium and are therefore a star. But if your mass is between 13 and 80 Jupiters, things get interesting. You can’t fuse hydrogen to shine brightly, but you can fuse lithium into other elements. This is known as lithium burning. It doesn’t provide lots of energy, but it is technically nuclear fusion.

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Brown Dwarfs can Spin so Fast They Almost Tear Themselves Apart

Comparing the rotation of a brown dwarf with Jupiter and Saturn. Credit: Robert Hurt (IPAC/Caltech)

We tend to image planets as spheres. Held together by gravity, the material of a planet compresses and shifts until gravity and pressure reach a balance point known as hydrostatic equilibrium. Hydrostatic equilibrium is one of the defining characteristics of a planet. If a planet were stationary and of uniform density, then at equilibrium, it would be a perfect sphere. But planets rotate, and so even the largest planets aren’t a perfect sphere.

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We Now Have a 3D Map of The 525 Closest Brown Dwarfs

Zooniverse brings out the best of the internet – it leverages the skills of average people to perform scientific feats that would be impossible otherwise.  One of the tasks that a Zooniverse project called Backyard Worlds: Planet 9 has been working on has now resulted in a paper cataloguing 525 brown dwarfs, including 38 never before documented ones.

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Astronomers see Swirling Weather on the Closest Brown Dwarf

An artist's conception of a brown dwarf. A new study identifies CK Vulpeculae as the remnant of a collison between a brown dwarf and a white dwarf. Image: By NASA/JPL-Caltech (http://planetquest.jpl.nasa.gov/image/114) [Public domain], via Wikimedia Commons
An artist's conception of a brown dwarf. A new study identifies CK Vulpeculae as the remnant of a collison between a brown dwarf and a white dwarf. Image: By NASA/JPL-Caltech (http://planetquest.jpl.nasa.gov/image/114) [Public domain], via Wikimedia Commons

Brown dwarfs are the weird not-planets but not-stars in the universe, and astronomers have wondered for decades if their atmospheres are striped like Jupiter’s, or splotchy like the sun’s. A team of astronomers based at the University of Arizona used NASA’s TESS Observatory to find the answer: if you saw a brown dwarf for yourself, it would look more like a giant planet than a star.

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Brown dwarf discovered with a radio telescope for the first time

Artist view of a cool brown dwarf. Credit: ASTRON / Danielle Futselaar

Brown dwarfs are interesting objects. They are generally defined as bodies massive enough to trigger the fusion of deuterium or lithium in their cores (and are thus not a planet) but too small to fuse hydrogen in their cores (and therefore not a star). They are the middle children of cosmic bodies.

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Astronomers find 100 brown dwarfs in our neighborhood

An artist's conception of a brown dwarf. A new study identifies CK Vulpeculae as the remnant of a collison between a brown dwarf and a white dwarf. Image: By NASA/JPL-Caltech (http://planetquest.jpl.nasa.gov/image/114) [Public domain], via Wikimedia Commons
An artist's conception of a brown dwarf. A new study identifies CK Vulpeculae as the remnant of a collison between a brown dwarf and a white dwarf. Image: By NASA/JPL-Caltech (http://planetquest.jpl.nasa.gov/image/114) [Public domain], via Wikimedia Commons

Brown dwarfs are smallish objects sitting somewhere between stars and planets, making them notoriously hard to find. But a recent citizen science project aimed at finding the elusive Planet 9 has instead revealed a treasure trove of these oddities, right next door.

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