Brian Koberlein, Author at Universe Today

October 29, 2022October 29, 2022 by Brian Koberlein

Not Just Gold. Colliding Neutron Stars Forge Strontium, Lanthanum, and Cerium

Artist’s conception of a neutron star merger. This process also creates heavy elements. Credit: Tohoku University

In the beginning, there was hydrogen and helium. Other than some traces of things such as lithium, that’s all the matter the big bang produced. Everything other than those two elements was largely produced by astrophysical rather than cosmological processes. The elements we see around us, those that comprise us, were mostly formed within the hearts of stars. They were created in the furnace of stellar cores, then cast into space when the star died. But there are a few elements that are created differently. The most common one is gold.

October 28, 2022October 28, 2022 by Brian Koberlein

JWST Sees the Same Galaxy From Three Different Angles Thanks to a Gravitational Lens

This illustration shows how gravitational lensing works. The gravity of a large galaxy cluster is so strong, it bends, brightens and distorts the light of distant galaxies behind it. The scale has been greatly exaggerated; in reality, the distant galaxy is much further away and much smaller. Credit: NASA, ESA, L. Calcada

One of the great tragedies of the night sky is that we will never travel to much of what we see. We may eventually travel to nearby stars, and even distant reaches of our galaxy, but the limits of light speed and cosmic expansion make it impossible for us to travel beyond our local group. So we can only observe distant galaxies, and we can only observe them from our home in the universe. You might think that means we can only see one face of those galaxies, but thanks to the James Webb Space Telescope that isn’t entirely true.

Remove All Ads on Universe Today

Join our Patreon for as little as $3!

Get the ad-free experience for life

October 26, 2022October 26, 2022 by Brian Koberlein

The Smallest, Lightest Neutron Star Ever Seen Could be a “Strange Star”

The supernova remnant HESS J1731-347 surrounding a small neutron star. Credit: Victor Doroshenko

The life of every star is a fight against gravity. Stars are so massive they risk collapsing under their own weight, but this is balanced by the heat and pressure a star generates through nuclear fusion. Eventually, that comes to an end. The outer layers of a star will be cast off, and the remaining core will become a stellar remnant. Which kind of remnant depends on the mass of the core.

October 23, 2022October 23, 2022 by Brian Koberlein

Scientists Find an Ancient Stellar Catalog Written by Hipparcus Hidden in a Medieval Tome

A folio from the Codex Climaci Rescriptus. Credit: Peter Malik

If you think writing paper is expensive these days, be glad you didn’t live in the middle ages. Back then, paper was as rare as hen’s teeth, so good luck finding some to write one. But if you happened to be a monk, chances are there were plenty of old books made of parchment. Many of them have useless stuff like old star catalogs, so why not just recycle the parchment for your new copy of religious literature?

October 20, 2022October 20, 2022 by Brian Koberlein

Astronomers Chart the Influence of Dark Matter and Dark Energy on the Universe by Measuring Over 1,500 Supernovae

Artist view of a supernova explosion. Credit: NASA

In 2011, the Nobel Prize in physics was awarded to Perlmutter, Schmidt, and Reiss for their discovery that the universe is not just expanding, it is accelerating. The work supported the idea of a universe filled with dark energy and dark matter, and it was based on observations of distant supernovae. Particularly, Type Ia supernovae, which have consistent light curves we can use as standard candles to measure cosmic distances. Now a new study of more than 1,500 supernovae confirms dark energy and dark matter, but also raises questions about our cosmological models.

October 15, 2022October 15, 2022 by Brian Koberlein

Astronomers Think They Have a Warning Sign for When Massive Stars are About to Explode as Supernovae

Artist's impression of Betelgeuse. Credit: ESO/L. Calçada

Red supergiant stars are explosions waiting to happen. They are in the last stage of their life, red and swollen as they fuse heavier elements in a last effort to keep from collapsing. But eventually, gravity will win and the red supergiant core will collapse, triggering a supernova. We know it will happen, but until recently, we didn’t know when.

October 7, 2022October 7, 2022 by Brian Koberlein

A Solar Gravitational Lens Will be Humanity's Most Powerful Telescope. What are its Best Targets?

mage of a simulated Earth, at 1024×1024 pixel resolution, at the distance of Proxima Centauri,at 1.3 pc, as projectedby the SGL to an image plane at 650 AU from the Sun. Credit: Toth H. & Turyshev, S.G.

One of the central predictions of general relativity is that a massive object such as a star, galaxy, or black hole can deflect light passing nearby. This means that light from distant objects can be gravitationally lensed by objects closer to us. Under the right conditions, gravitational lensing can act as a kind of natural telescope, brightening and magnifying the light of distant objects. Astronomers have used this trick to observe some of the most distant galaxies in the universe. But astronomers have also thought about using this effect a little closer to home.

October 2, 2022October 2, 2022 by Brian Koberlein

The Milky Way is Surrounded by a Vast Graveyard of Dead Stars

Distribution of stellar remains in the Milky Way. Credit: University of Sydney

Everything dies in the end, even the brightest of stars. In fact, the brightest stars are the ones that live the shortest lives. They consume all the hydrogen they have within a few million years, then explode as brilliant supernovae. Their core remains collapse into a neutron star or black hole. These small, dark objects litter our galaxy, like a cosmic graveyard.

September 30, 2022September 30, 2022 by Brian Koberlein

A Dwarf Galaxy Passed Close to the Milky Way and Left Ripples in its Wake

Artist's view of ripples on the edge of the Milky Way. Credit: NASA JPL-Caltech R. Hurt (SSC Caltech)

When you imagine the collision of galaxies, you probably think of something violent and transformational. Spiral arms ripped apart, stars colliding, cats and dogs living together, mass hysteria. The reality is much less dramatic. As a recent study shows, our galaxy is in a collision right now.

September 28, 2022September 28, 2022 by Brian Koberlein

Jupiter’s Atmosphere is Surprisingly Hot

Temperature measurements of Jupiter's upper atmosphere. Credit: James O’Donoghue

Jupiter is a big planet, but it’s still a planet. That means it doesn’t heat itself through fancy mechanisms like nuclear fusion. Its interior is heated through its own weight, squeezing the interior through hydrostatic equilibrium, and its surface is heated mostly by the Sun. Since Jupiter only gets about 4% of the light per square meter that Earth gets, you’d expect its upper atmosphere to be pretty cold. Traditional models estimate it should be about -70 degrees Celsius. But recent measurements show the upper atmosphere is over 400 degrees Celsius, and in the polar regions as much as 700 degrees Celsius. In the words of Ruby Rhod from the movie The Fifth Element, “It’s Hot Hot Hot!”