March 2017

Where Do We Come From? What Are We? Where Are We Going?

March 31, 2017

Is there something about human beings that ensures we will always explore? I think so, even while acknowledging that there are many who have chosen throughout history not to examine potential frontiers. The choices we make on Earth will be reflected in our future beyond the Solar System, assuming there is to be one. Nick […]

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Skyscraper in the Clouds

March 30, 2017

Analemma seems the perfect name for the proposed ‘floating’ space tower being discussed by the Clouds Architecture Office, an imaginative New York firm whose unusual designs include a Martian habitat made of ice and a concept study of flight into deep space using comets for resources. An analemma is a diagram that traces the movement […]

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A Retrograde Asteroid Sharing Jupiter’s Orbit

March 29, 2017

We recently looked at JAXA’s planned solar sail mission to Jupiter (see JAXA Sail to Jupiter’s Trojan Asteroids), but I want to come back around to the Trojans this morning in light of a discovery announced today. The more we learn about the Trojans, the better. Most appear to be class D asteroids, dark with […]

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The Challenges of Przybylski’s Star

March 28, 2017

About 370 light years away in the constellation Centaurus is a variable star whose spectrum continues to raise eyebrows. The star is laced with oddball elements like europium, gadolinium, terbium and holmium. Moreover, while iron and nickel appear in unusually low abundances, we get short-lived ultra-heavy elements, actinides like actinium, plutonium, americium and einsteinium. Hence […]

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Looking for Our Sun’s ‘Super-Earth’

March 27, 2017

An obscure instrument called a blink comparator became world famous following Clyde Tombaugh’s discovery of Pluto in 1930. It was by rapidly switching between astronomical photographs that the young Tombaugh was able to compare objects in the field of view where ‘Planet X’ was presumed to hide. Pluto turned out to be a good deal […]

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Astronomy Rewind: Keeping Our Data Alive

March 24, 2017

When I was growing up, there was a small outbuilding between my house and the stand of woods behind our property. The previous owner had built it as a little house in its own right, everything on a miniature scale, so that while it looked like an actual house — with front door, nice windows, […]

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Ceres: Axial Tilt and Surface Ice

March 23, 2017

Earth’s axial tilt (its obliquity) is 23.5 degrees, a significant fact for those of us who enjoy seasonal change. The ‘tilt’ is the angle between our planet’s rotational axis and its orbital axis. If we look at Earth’s obliquity over time, we find a 41,000 year cycle that oscillates between 22.1 and 24.5 degrees. Here […]

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Rosetta: Chronicling Cometary Change

March 22, 2017

Learning about the changes that occur on a cometary surface over time was a primary goal of the European Space Agency’s Rosetta mission, which orbited comet 67P/Churyumov-Gerasimenko between August 2014 and September 2016. This was a period when the comet was swinging through the inner Solar System as it closed to perihelion. Now we have […]

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Runaway Stars in Orion

March 21, 2017

Unexpected things can happen when you’re looking for exoplanets. Ask Kevin Luhman (Penn State), whose search for free-floating planets in the Orion Nebula is now telling us something interesting about star formation in general. In a small region dominated by young stars called the Kleinmann-Low Nebula, some 1300 light years from Earth near the center […]

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Star in Tight Orbit around Black Hole

March 20, 2017

Beyond their obvious value in advancing our knowledge, astronomical discoveries can be thought of as exercises for the imagination, making us think about what we would see if we were actually near the phenomenon being observed. The view from a planet deep in a globular cluster can only be spectacular, and has been the subject […]

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