July 2007

Notes & Queries for the Weekend

July 21, 2007

Those who have toiled in the vineyards of literary studies may recognize the allusion in my title to Notes & Queries, a journal collecting short pieces on a variety of research topics. Back in grad school I was forever looking up odds and ends in its pages related to the Anglo-Saxon alliterative line. A far […]

Read the full article →

Liquid Water in the Kuiper Belt?

July 20, 2007

As if New Horizons didn’t already have its work cut out for it, now we have the possibility of seeing a frigid geyser going off on Pluto’s companion Charon when the probe arrives in 2015. The process is called cryovolcanism, the movement of liquid water onto the surface where it freezes into ice crystals. New […]

Read the full article →

A Close Stellar Encounter?

July 19, 2007

Astronomers have found a highly elliptical debris disk around the star HD 15115, one that seen virtually edge-on from Earth gives the appearance of a needle running straight through its star. The disk was first imaged by the Hubble Space Telescope in 2006, its unusual shape causing astronomers to request near-infrared imaging by the W.M. […]

Read the full article →

Odds on the Human Future

July 18, 2007

I’m not very good at playing odds, though I do seem to pick up money routinely from a friend who is a Chicago Cubs fan (this year may be different — we’ll see). But bringing odds into the discussion of the Fermi Paradox can be an interesting exercise, and Princeton astrophysicist Richard Gott has already […]

Read the full article →

The Sun in a Crowded Sky

July 17, 2007

We’re so used to thinking of our Sun as a solitary object that having two Suns in the sky inspires the imagination of artist and writer alike. But what about whole clusters of stars? Evidence is mounting that the Sun was actually born in such a cluster. That’s quite a jump from the era, not […]

Read the full article →

Probing Radiation Hazards to Future Missions

July 16, 2007

A human presence in space is one day going to mean something more than putting a crew into low Earth orbit or even going to the Moon. But longer journeys — to Mars, to Jupiter’s moons and beyond — count among their many challenges the problem of radiation. To solve it, we’ll have to start […]

Read the full article →

Nanotech, Colony Worlds and the Long Jump

July 14, 2007

An obvious objection to the idea of human journeys to the stars is time — if we can’t find ways to reduce travel time to well within a human lifetime, so the thinking goes, then we’ll have to stick with robotics. But expand the timeframe through multi-generational ships and you change the parameters of the […]

Read the full article →

Outer Gas Giants Rare?

July 13, 2007

Centauri Dreams sometimes gets e-mail from readers asking how research results can be so contradictory. We’ve discussed gas giants around red dwarf stars, for example, noting theories that such planets are rare in this environment. And then we come up with stars like Gliese 876 and GJ 317, both red dwarfs, and both sporting not […]

Read the full article →

Water Vapor on a Hot Jupiter

July 12, 2007

Probing planetary atmospheres is tricky business at the best of times, but when you’re limited to planets you can’t even see, the project seems well nigh insurmountable. Nonetheless, astronomers using the Spitzer space telescope are having some success working in the infrared. They focus on transiting hot Jupiters, and earlier this year were able to […]

Read the full article →

Planetary Debris and Its Effects

July 11, 2007

Since we’ve just been looking at stellar metallicity and planet formation, news from the European Southern Observatory catches my attention. A new paper from ESO astronomers discusses the question of planetary debris falling onto the surface of stars, and its effects on what we observe. Evidence has been accumulating that planets tend to be found […]

Read the full article →