Evan Gough, Author at Universe Today

January 29, 2019January 29, 2019 by Evan Gough

Without the Impact that Formed the Moon, We Might Not Have Life on Earth

The chemicals that made life possible on Earth may have come from another planet that collided with Earth, forming the Moon. Image Credit: Rice University

The Earth wasn’t formed containing the necessary chemicals for life to begin. One well-supported theory, called the “late veneer theory”, suggests that the volatile chemicals needed for life arrived long after the Earth formed, brought here by meteorites. But a new study challenges the late veneer theory.

Evidence shows that the Moon was created when a Mars-sized planet named Theia collided with the Earth. The impact created a debris ring out of which the Moon formed. Now, this new study says that same impact may have delivered the necessary chemicals for life to the young Earth.

January 25, 2019January 25, 2019 by Evan Gough

Quasars with a Double-Image Gravitational Lens Could Help Finally Figure out how Fast the Universe is Expanding

A Hubble Space Telescope image of a doubly-imaged quasar. Image Credit: NASA Hubble Space Telescope, Tommaso Treu/UCLA, and Birrer et al

How fast is the Universe expanding? That’s a question that astronomers haven’t been able to answer accurately. They have a name for the expansion rate of the Universe: The Hubble Constant, or Hubble’s Law. But measurements keep coming up with different values, and astronomers have been debating back and forth on this issue for decades.

The basic idea behind measuring the Hubble Constant is to look at distant light sources, usually a type of supernovae or variable stars referred to as ‘standard candles,’ and to measure the red-shift of their light. But no matter how astronomers do it, they can’t come up with an agreed upon value, only a range of values. A new study involving quasars and gravitational lensing might help settle the issue.

January 24, 2019January 24, 2019 by Evan Gough

A Planetary Nebula Like This Will Only be Visible for About 10,000 Years Before it Fades Away

The ESO's VLT captured this image of planetary nebula ESO 577-24 as part of its Cosmic Gems Programme. Image Credit: ESO

For some stars, their last act is a final exhalation of gases, which we call a planetary nebula. While a living being’s last breath is closely followed by death, a star can continue to shine. And that shining illuminates the final exhalation of gases like a cosmic, diaphanous veil.

Astronomers have captured one such planetary nebula in this stunning image. This brightly-lit, stellar exhalation will last only 10,000 years, a brief moment in astronomical terms. As the last breath expands and travels away from the star that exhaled it, it will become diffuse and will no longer be visible. All that will be left is the tiny and intensely hot remnant of the star that spawned it.

January 23, 2019January 23, 2019 by Evan Gough

One of Our Best Views of the Supermassive Black Hole at the Heart of the Milky Way

Top left: simulation of Sgr A* at 86 GHz without interstellar scattering. Top right: simulation with interstellar scattering. Bottom right: observed image of Sgr A*. Bottom left: observed image of Sgr A* after removing the effects of interstellar scattering. Credit: S. Issaoun, M. Mo?cibrodzka, Radboud University/ M. D. Johnson, CfA

An almost unimaginably enormous black hole is situated at the heart of the Milky Way. It’s called a Supermassive Black Hole (SMBH), and astronomers think that almost all massive galaxies have one at their center. But of course, nobody’s ever seen one (sort of, more on that later): It’s all based on evidence other than direct observation.

The Milky Way’s SMBH is called Sagittarius A* (Sgr. A*) and it’s about 4 million times more massive than the Sun. Scientists know it’s there because we can observe the effect it has on matter that gets too close to it. Now, we have one of our best views yet of Sgr. A*, thanks to a team of scientists using a technique called interferometry.

January 23, 2019January 23, 2019 by Evan Gough

A Disc of Icy Material, not Planet 9, Might Explain the Strange Movements in the Outer Solar System

Could a disk of icy material be responsible for the strange orbits of distand objects in our Solar System? Image Credit: ESO/M. Kornmesser

Is there or isn’t there a Planet 9? Is there a planet way out on the outskirts of our Solar System, with sufficient mass to explain the movements of distant objects? Or is a disc of icy material responsible? There’s no direct evidence yet of an actual Planet 9, but something with sufficient mass is affecting the orbits of distant Solar System objects.

A new study suggests that a disc of icy material causes the strange movements of outer Solar System objects, and that we don’t need to invent another planet to explain those movements. The study comes from
Professor Jihad Touma, from the American University of Beirut, and
Antranik Sefilian, a PhD student in Cambridge’s Department of Applied Mathematics and Theoretical Physics. Their results are published in the Astronomical Journal.

January 22, 2019January 22, 2019 by Evan Gough

Saturn’s Rings are Only 10 to 100 Million Years Old

Saturn's rings in all their glory. Image from the Cassini orbiter as Saturn eclipsed the Sun. Image Credit: By NASA / JPL-Caltech / Space Science Institute

Can you imagine the Solar System without Saturn’s rings? Can you envision Earth at the time the dinosaurs roamed the planet? According to a new paper, the two may have coincided.

Data from the Cassini mission shows that Saturn’s rings may be only 10 to 100 million years old. They may not have been there during the reign of the dinosaurs, and may in fact be a fairly modern development in our Solar System.

January 18, 2019January 18, 2019 by Evan Gough

Cassini Saw Rain Falling at Titan’s North Pole

An image from the Nasa-Esa-Asi Cassini spacecraft provides evidence of rainfall on the north pole of Titan. Image Credit: NASA/ESA/ASI/Cassini.

The Cassini mission to Saturn ended in September 2017, but the data it gathered during its 13 year mission is still yielding scientific results. On the heels of a newly-released global image of Saturn’s moon Titan comes another discovery: Rainfall at Titan’s north pole.

Climate models developed by scientists during Cassini’s mission concluded that rain should fall in the north during Titan’s summer. But scientists hadn’t seen any clouds. Now, a team of scientists have published a paper centered on Cassini images that show light reflecting off a wet surface. They make the case that the reflecting light, called a Bright Ephemeral Flare (BEF) is sunlight reflecting from newly-fallen rain.

January 17, 2019January 17, 2019 by Evan Gough

CERN is Planning to Build a Much Larger Particle Collider. Much, Much, Larger.

CERN's Future Circular Collider. Image Credit: CERN

CERN, the European Organization for Nuclear Research, wants to build a particle collider that will dwarf the Large Hadron Collider (LHC). The LHC has made important discoveries, and planned upgrades to its power ensures it will keep working on physics problems into the future. But eventually, it won’t be enough to unlock the secrets of physics. Eventually, we’ll need something larger and more powerful.

Enter the Future Circular Collider (FCC.) The FCC will exceed the LHC in power by an order of magnitude. On January 15th, the FCC collaboration released its Conceptual Design Report (CDR) that lays out the options for CERN’s Future Circular Collider.

January 17, 2019January 17, 2019 by Evan Gough

Astronomers Aren’t Pleased About a Russian Plan to Put Billboards in Space

A screen capture from StartRocket's promotional video for their Orbital Display. Image Credit: StartRocket.

It was bound to happen.

While the rest of us look up at the night sky, and wonder at what we’re seeing, ponder how it all fits together, and strain ourselves trying to understand how our origins are intertwined with all that we see, others don’t. They look up at the magnitude of the night sky and think none of these things.

Instead they think, “Hmmm…that’s a big, empty billboard. How can I make money from it?”

January 16, 2019January 16, 2019 by Evan Gough

The Prototype for the Starship has been Assembled, Hop Tests Could be Happening Soon

In an announcement sure to make you quiver with delight, Elon Musk says that SpaceX could begin short-hop test flights of its Starship prototype as early as next Spring. The Starship, which looks like something from a 1950’s sci-fi novel cover (awesome!) is intended to carry people to the Moon and Mars. When the spacecraft design was originally announced in 2016, it was called the Mars Colonial Transporter, and it sent shockwaves through the community.

Now, it’s almost test-flight time.