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Grand Finale

In Solar System by Brian Koberlein0 Comments

More than a decade ago the Cassini probe entered orbit around Saturn. It was a risky mission. We had never orbited such a distant planet, which meant there was plenty to go wrong. Cassini also carries a companion probe, known as Huygens, which had a mission to land on Titan. Cassini has been a remarkable success, and has given us an unprecedented view of Saturn and its moons. But now the aging spacecraft is running out of power, so it’s time for Cassini to have one last mission. Read More

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Legends Of The Cold

In History by Brian Koberlein6 Comments

From 1645 to 1715 the Sun entered an extended quiet period known as the Maunder minimum. During that time there was almost no observed sunspot activity on the Sun. It was also a period of abnormally cold winters in Europe, known as the Little Ice Age. A similar, but smaller period of solar quiet from 1796 to 1820 (known as the Dalton solar minimum) correlates to the period of Charles Dickens’ childhood, whose books engrained the idea of a “White Christmas” in English society. These events support the idea that sunspot activity could have an effect on global temperatures. But a new look at the Little Ice Age finds that the connection isn’t quite so clear. Read More

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Millions In Motion

In Astronomy by Brian Koberlein0 Comments

Our Sun is adrift among the stars. As our home star moves through the galaxy, so to do the other stars. This means that the apparent positions of the stars change over time. Because of the great distances of stars this shift is minuscule and difficult to measure. For years we have only been able to measure the motion of a few close stars. But that’s beginning to change. Read More

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Hello, Rock!

In Meteors by Brian Koberlein1 Comment

One of the questions I’m asked from time to time is whether a funny looking rock someone found is a meteorite. The short answer is no, since meteorites are extremely rare. The not-so-short answer is that it probably isn’t a meteorite, but there are some basic tests you can do yourself. Read More

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Black Holes And Dark Matter

In Black Holes by Brian Koberlein3 Comments

Over the years, dark matter has remained an enigma. Observations of things like large scale galaxy distribution and the motion of stars and gas within galaxies points to the existence of some sort of weakly interacting matter, we still haven’t figured out what this dark matter could be. We know a lot of things it can’t be, such as neutrinos, but the solution still eludes us. So one idea that keeps coming back is that dark matter might be due to black holes. Not stellar mass black holes formed from dying stars, or supermassive black holes found in the centers of galaxies, but smaller black holes that may have formed in the early universe. Read More

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ALMA Sees Hydrogen Super-Halos Around Young Spiral Galaxies

In Galaxies by Brian Koberlein3 Comments

Young galaxies are often surrounded by a halo of hydrogen gas. Over time this gas can be pulled inward, where it can feed star production in the galaxy. While we’ve known these halos existed, it has been difficult to determine their size. But new research from the Atacama Large Millimeter/submillimeter Array (ALMA) has found that some galactic halos are surprisingly large. Read More

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Nitrogen Powered

In Solar System by Brian Koberlein0 Comments

If you’ve ever enjoyed a fizzy drink, you know how a gas can bubble out of a liquid. Pick up a bottle of soda, for example, and it looks like an ordinary liquid. But when you open the bottle, small bubbles start to form, rising to the top of the liquid. If you’re not careful, the bubbles can even cause the soda to froth out of the bottle. This frothing effect might also explain strange island-like structures on the surface of Saturn’s moon Titan, which seem to appear and disappear from time to time. Read More