Thomas Paine

To argue with a person who has renounced the use of reason is like administering medicine to the dead.

Tuesday, January 1, 2013

Centauri Dreams

The location of Alpha Centauri A and B, Proxim...
The location of Alpha Centauri A and B, Proxima Centauri and the Sun in the Hertzsprung-Russell (HR) diagram. (Photo credit: Wikipedia)
English: Apparent orbit of Alpha Centauri by p...
English: Apparent orbit of Alpha Centauri by professor see (Photo credit: Wikipedia)
English: Alpha Centauri
English: Alpha Centauri (Photo credit: Wikipedia)

Centauri Dreams


Planet Discovery Through Disk Structure
As the number of confirmed planets and planet candidates has grown, we’ve gone through a variety of techniques for exoplanet hunting, as Michael Lemonick’s new book Mirror Earth: The Search for Our Planet’s Twin (Walker & Co., 2012) makes clear. I’m only a third of the way into the book but I bring it up because it’s germane to today’s discussion in two ways. The first is purely administrative. Readers of Centauri Dreams are used to seeing information about the book I’m reading on the front page, but as many emails have reminded me, lately it’s been absent. What’s happening is this: The s
A New Year Awaits
I’ve gotten so used to thinking ‘maybe this will be the year when the first Alpha Centauri planet is discovered’ that I almost said it again about 2013. Fortunately, we already have a (still unconfirmed) Centauri B b, and the latest I’ve heard is that it may take five years or so before we can say something definitive about a planet in a habitable zone orbit around our neighboring system. So the coming year may not be the year of Alpha Centauri, but we can expect exoplanet news in abundance as the various teams continue their work, and plenty of activity from the organizations now working to a
Alpha Centauri in Perspective
In his new article on Alpha Centauri in Astronomy & Geophysics, Martin Beech (Campion College, University of Regina) noted that the Alpha Centauri stars seem to go through waves of scientific interest. Beech used Google’s Ngram Viewer to look for references to the system in both the scientific literature as well as general magazines and newspapers, finding that there is a 30-year interval between peaks of interest. The figure is suspiciously generational, and Beech wonders whether it reflects an awakening of interest in this nearby system as each generation of scientists and publishers ari

Dec 24 2012

Best Wishes for a Stellar Holiday
Martin Beech has written a superb summary of Alpha Centauri studies for the Royal Astronomical Society’s journal Astronomy and Geophysics, covering recent work up to and including the discovery of planet candidate Centauri B b. A fine holiday gift! I had been hoping to write it up this morning, but Christmas events, not least of which is the need for some last minute shopping, have made that impos

Dec 21 2012

New Models of Galactic Expansion
Unexpectedly waking this morning despite Mayan prophecy, I suddenly remembered the storms that had kept me up for an hour during the night. There was little rain, but the winds were gusting and I could hear trees branches slapping against the siding and dogs baying inside nearby houses. When I got up to look out the window, city light under the overcast created a dim bronze aura. You would think i

Dec 20 2012

Tightly Spaced Habitable Zone Candidates
We saw yesterday how a newly refined radial velocity technique allowed researchers to identify five planet candidates around the nearby star Tau Ceti. The latter has long held fascination for the exoplanet minded because it’s a G-class star not all that different from the Sun, and one of the planets around it — if confirmed — appears to be in its habitable zone. But smaller stars remain much in th

Dec 19 2012

Tau Ceti’s Five Planet Candidates
I discovered while trying to get to my copy of Stephen Dole’s Habitable Planets for Man that my office was so choked with stacks of books mixing with Christmas gifts about to be wrapped that I couldn’t reach the necessary shelf. Thus space studies end inevitably in office cleaning, the only benefit of which is that there is now a clear path to the most distant of the bookshelves and Dole’s book (t

Dec 18 2012

Solar System Origins: No Supernova?
How do we get from clouds of gas and dust in interstellar space to stars like the Sun? It takes the right triggering event, which can cause such a cloud to collapse under its own gravity, and we’ve generally assumed that the trigger was a supernova. Indeed, one way to check the theory is to look for the radioactive isotope iron 60 (60Fe), which is considered a marker for a supernova as it can only

Dec 17 2012

An Early Nod to Beamed Propulsion
It’s always interesting how different strands of research can come together at unexpected moments. The last couple of posts on Centauri Dreams have involved new work on Titan, and early references in science fiction to Saturn’s big moon. The science fiction treatments show the appeal of a distant object with an atmosphere, with writers speculating on its climate, its terrain, and the bizarre life-

Dec 14 2012

Titan: A Vast, Subsurface Ocean?
Yesterday’s look at a major river on Titan took on a decidedly science fictional cast, but then Titan has always encouraged writers to speculate. Asimov’s “First Law” (1956) tackles a storm on Titan as a way of dealing with the Three Laws of Robotics. Arthur C. Clarke filled Titan with a large human colony in Imperial Earth (1976), and Kim Stanley Robinson used Titanian nitrogen in his books on th

Dec 13 2012

Titan’s Big River
One of the wonderful things about daily writing is that I so often wind up in places I wouldn’t have anticipated. Today’s topic includes the discovery of a long river valley on Titan that some are comparing to the Nile, for reasons we’ll examine below. But the thought of rivers on objects near Saturn invariably brought up the memory of a Frank R. Paul illustration, one that ran as the cover of the

Dec 12 2012

Widening the Habitable Zone
Finding a way to extend the classical habitable zone, where liquid water can exist on the surface of a planet, is a project of obvious astrobiological significance. Now a team of astronomers and geologists from Ohio State University is making the case that their sample of eight stars shows evidence for just such an extension. The stars in question, drawn from a dataset created by the High Accuracy

Dec 11 2012

Thoughts on Patrick Moore
Patrick Moore, the legendary figure of British astronomy who died recently at his home in West Sussex, was deeply familiar with Ptolemy. The latter, a 2nd Century AD mathematician and astronomer, was the author of the Almagest, an astronomical treatise that presented the universe as a set of nested spheres and assumed a geocentric cosmos. Moore’s comprehensive knowledge of astronomy’s history woul

Dec 10 2012

Interstellar Flight: The View from Kansas
If Kansas may not be the first place that comes to mind when you think about interstellar matters, be aware that its state motto is ‘Ad Astra Per Aspera’ — to the stars through difficulties. That’s a familiar phrase for anyone who has pondered the human future in space, appearing in countless science fiction stories and often invoked by those with a poetical streak. It turns out that the Kansas mo

Dec 07 2012

Brown Dwarf Results Promising for Planets
Do planets form easily around brown dwarf stars? Are they actually common? We’re getting a glimpse of the possibilities in new work at the Atacama Large Millimeter/submillimeter Array (ALMA), where a brown dwarf known as ISO-Oph 102 (also called Rho-Oph 102) is under investigation. In most respects it seems like a fairly run-of-the-mill brown dwarf, about 60 times the mass of Jupiter and thus una

Dec 05 2012

Voyager: Dark Highway Ahead
One rainy night in the mid-1980s I found myself in a small motel in the Cumberlands, having driven most of the day after a meeting and reaching Newport, TN before I decided to land for the night. It’s funny what you remember, but small details of that trip stick with me. I remember the nicking of the wiper blades as I approached Newport, the looming shapes of the mountains in the dark, and most of

Dec 04 2012

ASPW 2012: A Report from Huntsville
Richard Obousy, a familiar face on Centauri Dreams, is president and primary propulsion senior scientist for Icarus Interstellar, whose portfolio includes Project Icarus, the redesign of the Project Daedalus starship. Dr. Obousy is just back from the latest Advanced Space Propulsion Workshop and, as he did for the 2010 ASPW, he now offers his take on the event. Although I missed this ASPW, I’ll be

Dec 03 2012

Skylon: Promising Tests of the SABRE Engine
The news from Reaction Engines Ltd. about its air-breathing rocket engine SABRE is interesting not only for its implications in near-term space development, but also for its pedigree. Reaction Engines grew out of British work on a single-stage-to-orbit concept called HOTOL ((Horizontal Take-Off and Landing) that was being developed by Rolls Royce and British Aerospace in the 1980s. Initially backe
4 by Paul Gilster / 29 days ago
Enhanced by Zemanta

No comments:

Post a Comment