An astronomical saga of star births, pancakes, and Kylo Ren

[ This blog is dedicated to tracking my most recent publications. Subscribe to the feed to keep up with all the science stories I write! ]

And if I can be shameless: Forbes pays according to traffic, so the more of you who share and visit and read my stuff, the better they pay me. Ahem.

The Hidden Depths Of The Dark Cloud Hiding Newborn Stars

For Forbes:

The third dimension is one of the biggest obstacles in astronomy. We see the stars, but we don’t know how far away they are without some additional information, which requires scientific cleverness. And when the object we’re studying is a nebula — a cloud of gas or dust — we only see its profile, not its full three-dimensional shape. But a new paper shows that, in some cases, we might be able to deduce the full shape of a nebula by how it vibrates: a kind of magnetic nebulaquake.

Astrophysicists Aris Tritsis and Konstantinos Tassis compared a sophisticated computer simulation to observational data on an object called the “Musca molecular cloud”, also known as the “Dark Doodad”. (“Musca” is the name of the constellation where it’s found, which means “the fly”. It’s only visible in the Southern Hemisphere.) They found that even though the Doodad looks like a filament, it’s actually more like a pancake that we’re seeing edge-on. Beyond the curiosity aspect (who wouldn’t want to study the Dark Doodad?), this result is important for understanding how stars are born.

[Read the rest at Forbes…]

Advertisements

Yerkes Observatory: 1897-2018

[ This blog is dedicated to tracking my most recent publications. Subscribe to the feed to keep up with all the science stories I write! ]

A few years ago, I visited Yerkes Observatory while driving across the country to gather material for a book that never came to fruition. It’s a marvelous relic of astronomy on the cusp of modernity, so when I heard it was closing its doors, I knew I had to write about it. Thankfully, Astronomy Magazine let me use some of my research from my book, including a few photographs. The following is a story of robber barons, huge telescopes, and an early unrecognized discovery of Pluto.

Yerkes Observatory is closing its doors

Once state of the art, this Gilded Age observatory has been left behind by progress. Now astronomers wonder what will happen to this piece of history.

Yerkes Observatory dome for the 40-inch refracting telescope. I rendered this photo in black and white for an old-timey feel, because why not? [Credit: moi]

For Astronomy Magazine:

A piece of astronomical history is closing its doors this year: Yerkes Observatory, which opened in 1897, will cease operations on October 1, 2018.

In many ways, this closure isn’t surprising. Yerkes is very much a relic of a past era, not the type of observatory that is used for major discoveries in the modern day. The University of Chicago, which owns and operates the facility, has decided the observatory is not worth the expense of maintaining it. However, we can hope someone will take over the operations and keep the building open to the public, because it’s truly one of the great pieces of scientific history and architecture. Yerkes Observatory is an impressive late-19th-century structure, housing what is still the largest refracting (lens-based) telescope in the world. The primary lens in the main Yerkes telescope is 40 inches (102 centimeters) in diameter. The observatory was named for the impressively mustached railroad tycoon Charles Yerkes, who bankrolled it in Gilded Age style. (The name is pronounced “YER-keys,” and the less said about how Yerkes ran his businesses, the better. “Yerkes was jerky” is a good mnemonic.)

The observatory stands on the shore of Geneva Lake in Williams Bay, Wisconsin, just across the border from Illinois. The land is sits on is parklike, and the building itself is a marvel of astronomical architecture and engineering from the dawn of the modern era of big science.

[Read the rest at Astronomy Magazine]

Discovering new planets with artificial intelligence

[ This blog is dedicated to tracking my most recent publications. Subscribe to the feed to keep up with all the science stories I write! ]

Thanks to Google AI, Astronomers Have Found New Planets

They’re not habitable, but the dual discoveries change how we’re going to hunt for the next Earth.

For The Daily Beast:

For the first time, NASA has used machine learning to identify two new planets in distant star systems. One of those worlds is the eighth in its system, making that planetary system the largest-known yet discovered.

We know stars can have eight planets already (hello, Solar System!), so that’s no surprise. The excitement comes in how this new world was found: using an artificial intelligence machine learning method known as “neural networks.”

On Thursday afternoon, Christopher Shallue, a senior software engineer at Google Brain, and Andrew Vanderburg, an astrophysicist at the University of Texas at Austin, announced the new worlds in a press conference. It’s the eighth planet orbiting the 90th star in the Kepler observatory’s catalog, so it carries the name Kepler-90i. It’s a smallish, rocky planet orbiting very close to its host star. This method also identified a fifth planet in the Kepler-80 system, described in the same research paper.

[Read the rest at The Daily Beast]

My new series on black holes!

[ This blog is dedicated to tracking my most recent publications. Subscribe to the feed to keep up with all the science stories I write! ]

I’ve just started a new series on black holes for Medium members. The first part is available now, with three more parts to come. And if enough of you read, they may keep me around to write more, so please read and share!

Exploring Black Holes: Frozen Stars and Gravitational Dynamos

Black holes are gravitational superheroes. Here is their origin story, including World War I, magnificent mustaches, and Albert Einstein

For Medium:

February 11, 2016, was a landmark day. After many decades of searching, scientists announced they had detected gravitational waves for the first time: disturbances in the structure of space-time that travel at light speed. But there was a second triumph of physics hiding inside that one. The waves gave us the best evidence so far for the existence of some of the most fascinating objects in our universe: black holes.
Few scientists these days doubt that black holes exist. But in a way, all our evidence for them is circumstantial. Black holes, by their very nature, are difficult to observe. All light falling on them is absorbed, rendering them nearly invisible.
On the other hand, black holes are the strongest gravitational powerhouses possible. When they strip matter off stars or out of interstellar gas clouds, that material heats up and shines brightly. It’s a seeming paradox: invisible objects that end up being some of the brightest things in the universe. The black holes known as quasars can be seen billions of light-years away. [read the rest at Medium…]

How standard are “standard candles”?

[ This blog is dedicated to tracking my most recent publications. Subscribe to the feed to keep up with all the science stories I write! ]

Not-so-standard candles

From Physics World:

The story is already legendary. In the late 1980s and early 1990s, two groups of rival researchers set out to measure the deceleration of the expanding universe. These groups often used the same observatory, sometimes even using the same telescope on consecutive nights. And they both found the same thing, publishing their results at roughly the same time in 1998–1999: the expansion of space–time isn’t slowing down at all. In fact, it’s getting faster. The leaders of those collaborations – Saul Perlmutter and Brian Schmidt – along with Adam Riess of the latter’s group, won the Nobel Prize for Physics in 2011 for this discovery. The implication of the result was that the universe consists not only of visible matter and dark matter, but also a gravitationally repulsive substance. Known as dark energy, the nature of this weird stuff remains as mysterious today as when it was first discovered.

Both groups used certain kinds of exploding stars called type Ia supernovae for their measurements. These supernovae brighten and fade in very similar ways and the current thinking is that this is because they have a common source: the explosion of either one or two white dwarfs, which are the stellar remnants of small-to-medium-mass stars such as the Sun. This consistent brightness allows astronomers to determine how far away the object was when the light left it and for that reason, type Ia supernovae are known as “standard candles” – reliable light- houses in the measurement of cosmic distances.

Or so we all thought.

The rest of this story is in the print edition of Physics World, which you can subscribe to through membership in the Institute of Physics, which costs £15, €20, or $25 per year. You can join by clicking here. You can also get a nice mobile- and tablet-formatted version of the story using the Physics World app, available in the Google Play and iTunes stores. However, if you just want to read the rest of this article, Physics World has kindly allowed me to offer it to you as a PDF download, which looks exactly like the printed version!

A white dwarf murder mystery

[ This blog is dedicated to tracking my most recent publications. Subscribe to the feed to keep up with all the science stories I write! ]

What killed the white dwarfs? (Aside from the giant explosion)

Merger or extra matter? Two papers come to opposite conclusions

For Ars Technica:

Type Ia supernovae are explosions that occur when white dwarfs strip matter off a companion star, exceed their maximum possible mass, and blow up.

No, wait: type Ia supernovae are the explosions caused when two white dwarfs collide.

While it’s reasonably certain that white dwarfs—the Earth-size remnant of stars similar to the Sun—are involved, the observational evidence for how these supernovae actually explode is messy. This week’s issue of Nature is a prime example: two back-to-back papers provide evidence for a white dwarf-companion star explosion and a two-white-dwarf collision scenario, respectively. Ultimately, these apparently contradictory results could mean there are two distinct types of white dwarf supernovae… or that we still don’t understand what’s going on.

The stakes are high. Unlike other supernovae, which involve the death of a star much more massive than the Sun, type Ia supernovae all explode in very similar ways. The pattern of light they emit during and after the explosion provides a reliable measurement of how far away they are. Since supernovae are bright enough to be visible from billions of light-years away, astronomers use them to measure the expansion and acceleration rate of the Universe, as recognized in the 2011 Nobel Prize in physics. Because they are so important to cosmology, researchers want to understand what objects are involved in the explosion and exactly how they blow up. [Read the rest at Ars Technica…]

Now it can be told: I will be writing a weekly post for The Daily Beast (making me The Weekly Beast?), on space, astronomy, and such things. My first column is about inflation, and why it’s a big deal:

If you compare any two points on the night sky, their temperature as measured in microwave light is identical to a few millionths of a degree. That light, known as the cosmic microwave background, comes to us from nearly the beginning of the Universe, so it has been traveling for 13.8 billion years. Even with the expansion of the cosmos, two points on opposite sides of the sky were never in the same place, yet they have the same temperature… assuming the current rate of the expansion of the Universe has been roughly the same since the beginning.

But maybe it hasn’t. The cosmic temperature coincidence (which would be a great band name), along with several other annoying aspects of the Universe, led a group of researchers to propose the theory of inflation. [read more…]

The Daily Beast’s latest astronomy columnist is…me!