Evan Gough, Author at Universe Today

June 28, 2023June 28, 2023 by Evan Gough

A Feline in the Heavens: The Smiling Cat Nebula

This is the Smiling Cat Nebula, aka Sh2-284. It's a stellar nursery of ionized hydrogen, powered by young stars in the center. If you can't see the cat, maybe you're more of a dog person. Image Credit: ESO/VPHAS+ team. Acknowledgement: CASU

A stellar nursery sounds like a placid place where baby stars go about their business undisturbed. But, of course, a stellar nursery is nothing like that. (Babies are noisy and cry a lot.) They’re dynamic places where powerful elemental forces rage mightily and bend the surroundings to their will. And this one, even though its name is the drowsy-sounding Smiling Cat Nebula, is no exception.

June 27, 2023June 27, 2023 by Evan Gough

A New Way to Measure Distances in the Universe

Image of the large-scale structure of the Universe, showing filaments and voids within the cosmic structure. Credit: Millennium Simulation Project. Now, the latest FLAMINGO simulation provide more detail about the evolution of the Universe within these structures. — Image of the large-scale structure of the Universe, showing filaments and voids within the cosmic structure. The latest FLAMINGO simulation provide more detail about the evolution of the Universe. Credit: Millennium Simulation Project

If we want to understand the Universe, we have to start with its size. Ancient people had no idea there was a Universe the way we understand it now, and no idea of its size. They thought there was the Earth, with everything else rotating around it. It was the only conclusion within reach for a long time.

June 16, 2023June 16, 2023 by Evan Gough

Earth Might Have Formed in Just a Few Million Years

Planets form by accreting material from a protoplanetary disk. New research suggests it can happen quickly, and that Earth may have formed in only a few million years. Credit: NASA/NASA/JPL-Caltech

Earth formed about 4.6 billion years ago. That simplistic statement is common, and it’s a good starting point for understanding our planet and our Solar System. But, obviously, Earth didn’t form all at once. The process played out for some period of time, and the usual number given is about 100 million years.

New research suggests that Earth formed more quickly than that in only a few million years.

June 15, 2023June 15, 2023 by Evan Gough

Did Life Need Plate Tectonics to Emerge?

New research indicates that mobile plate tectonics—thought to be necessary for the creation of a habitable planet—was not occurring on Earth 3.9 billion years ago. Image Credit: University of Rochester illustration / Michael Osadciw

It’s widely accepted that Earth’s plate tectonics are a key factor in life’s emergence. Plate tectonics allows heat to move from the mantle to the crust and plays a critical role in cycling nutrients. They’re also a key part of the carbon cycle that moderates Earth’s temperature.

But new research suggests that there was no plate tectonic activity when life appeared sometime around 3.9 billion years ago. Does this have implications for our search for habitable worlds?

June 14, 2023June 14, 2023 by Evan Gough

A White Dwarf is Starting to Crystallize into Diamond

An artist’s impression of crystallization in a white dwarf star. The twho known white dwarf pulsars may have interiors like this. Image credit: Mark Garlick / University of Warwick.

White dwarfs are the stellar remnants of stars like our Sun. They’re strange objects, and astrophysicists think their cores can crystallize into enormous diamonds. But they need to find more of these strange objects, and they need to know their ages, to understand how and when it happens.

June 12, 2023June 12, 2023 by Evan Gough

The Tarantula Nebula Shouldn’t Be Forming Stars. What’s Going On?

30 Doradus, also known as the Tarantula Nebula, is a region in the Large Magellanic Cloud. Streamlines show the magnetic field morphology from SOFIA HAWC+ polarization maps. These are superimposed on a composite image captured by the European Southern Observatory’s Very Large Telescope and the Visible and Infrared Survey Telescope for Astronomy. Credit: Background: ESO, M.-R. Cioni/VISTA Magellanic Cloud survey. Acknowledgment: Cambridge Astronomical Survey Unit. Streamlines: NASA/SOFIA

The Tarantula Nebula is a star formation region in the Large Magellanic Cloud (LMC). Tarantula is about 160,000 light-years away and is highly luminous for a non-stellar object. It’s the brightest and largest star formation region in the entire Local Group of galaxies.

But it shouldn’t be.

June 9, 2023June 9, 2023 by Evan Gough

Geoengineering is Shockingly Inexpensive

Geoengineering isn't a quick fix for our climate crisis, and it's also expensive. Image Credit: University of Leeds

Despite decades of warnings and international climate agreements, global carbon emissions are still rising. Carbon emissions seem like an unstoppable juggernaut as energy-hungry humans keep breeding and pursuing more affluent lifestyles. Reducing emissions won’t be enough to confront the climate crisis; we need additional solutions.

Geoengineering, also called climate engineering, could be the solution we seek. But is it financially feasible?

June 7, 2023June 7, 2023 by Evan Gough

Is it Time for a New Definition of “Habitable?”

This artist’s impression shows the planet Proxima b orbiting the red dwarf star Proxima Centauri, the closest star to the Solar System. The double star Alpha Centauri AB also appears in the image between the planet and Proxima itself. Proxima b is a little more massive than the Earth and orbits in the habitable zone around Proxima Centauri, where the temperature is suitable for liquid water to exist on its surface. Credit: ESO/M. Kornmesser

Things tend to move from the simple to the complex when you’re trying to understand something new. This is the situation exoplanet scientists find themselves in when it comes to the term ‘habitable.’ When they were discovering the first tranche of exoplanets, the term was useful. It basically meant that the planet could have liquid water on its surface.

But now that we know of over 5,000 confirmed exoplanets, the current definition of habitable is showing its age.

June 7, 2023June 7, 2023 by Evan Gough

JWST Shows How the Early Universe Was Furiously Forming Stars

This infrared image from NASA’s James Webb Space Telescope (JWST) was taken for the JWST Advanced Deep Extragalactic Survey, or JADES, program. It shows a portion of an area of the sky known as GOODS-South, which has been well studied by the Hubble Space Telescope and other observatories. More than 45,000 galaxies are visible here. Credits: NASA, ESA, CSA, Brant Robertson (UC Santa Cruz), Ben Johnson (CfA), Sandro Tacchella (Cambridge), Marcia Rieke (University of Arizona), Daniel Eisenstein (CfA). Image processing: Alyssa Pagan (STScI)

We can gaze out into regions in our neighbourhood of the Milky Way and find orgies of star birth. The closest region is in the Orion nebula, where astronomers have identified more than 700 young stars. They range from only 100,000 years—mere infancy for a star—to over a million years.

But we’re more than 13 billion years after the Big Bang now. What was star formation like way back when, when conditions in the Universe were so different?

June 6, 2023June 6, 2023 by Evan Gough

JWST Sees Organic Molecules Ludicrously Far Away

Astronomers using the Webb telescope discovered evidence of complex organic molecules in a galaxy more than 12 billion light-years away. In this false-color Webb image, the foreground galaxy is shown in blue, while the background galaxy is red. The organic molecules are highlighted in orange. Graphic courtesy J. Spilker / S. Doyle, NASA, ESA, CSA

When astronomers used the JWST to look at a galaxy more than 12 billion light years away, they were also looking back in time. And when they found organic molecules in that distant galaxy, they found them in the early Universe.

The organic molecules are usually found where stars are forming, but in this case, they’re not.