Tuesday, April 11, 2006

The Planet Police

Robert Roy Britt at Space.com's LiveScience blog has declared that Xena is not a planet and, judging from his somewhat petulant tone, he might just hold his breath until astronomers concede the point:

The world is not “Xena.” Officially, it is 2003 UB313.

But discoverer Mike Brown of Caltech is on a mission to have 2003 UB313 declared a planet, so he gave it a catchy nickname.

Other astronomers, and the good folks at Hubble, should not use the nickname. What they should do is finally agree on a definition for the word “planet.” And 2003 UB313 should not be included.

* * *

[T]hose who write press releases and journalists who cover all this should stop using the nickname “Xena” to describe 2003 UB313. Only when a proper definition for “planet” has been agreed on by the International Astronomical Union can astronomers decide on a name for the tiny, way-out world.
Now, I'll concede that there is no agreed-upon definition of a planet, but so what? If it walks like a duck . . . Indeed, just today, we learn that some astronomers believe Xena may behave very much like a "real" terrestial planet in that it might be geologically active, after a fashion. At least that's a leading explanation for Xena's wildly high albedo (its reflectivity).

Back in February, measurements of the amount light (of certain wavelengths) reflected by Xena's surface suggested that it was about 20-30% larger than Pluto. Recently, though, Hubble successfuly resolved Xena and it turns out that, while bigger than Pluto, it's not much bigger at all -- only about 5% (Pluto's diameter is 2290km while Xena's now appears to be about 2400km). Why then is it brighter than any other object in the Solar System excluding Enceladus (and, of course, the Sun itself). The geological theory holds that methane is extruded from Xena's interior and immediately freezes on the surface to give the planet an albedo akin to that of new-fallen snow. That, though, is as far as the theory goes. No one yet has a theory for why or how Xena extrudes methane.

As far as I can tell, Britt's distaste for "Xena" is a bit childish -- he just doesn't like the name, which has begun to stick, and is appealing to the what's-a-planet-really? debate as a means to wipe the slate clean for a do-over down the road. Whatever the result of the larger what's-a-planet-really? debate, I know this for certain: this far away rock will not be popularly known as 2003 UB313 . . .

Monday, April 10, 2006

A Safe Place, etc.

Spirit, one of the two little rovers that could, has finally reached the Martian equivalent of Florida -- a north-tilting slope on which it can safely weather the winter , i.e., obtain enough sunlight to keep its power levels above critical. Even if both Spirit and Opportunity were to go off-line tomorrow, the mission would still be one of the most succesful enterprises in the history of planetary science. That both are likely to make it through their third Martian winter to conduct yet further exploration is downright amazing. Sol 806 and (still) counting.

On another Mars-related note, the first HiRISE images from Mars Reconnaissance Orbiter are spectacular. The 50mb image is at APoD -- that's right, 50mb. You have been warned. A handful of other early images can be seen at NASA's MRO page. From its current location, HiRISE resolves about 2.5 meters per pixel. The resolution will increase by a factor of 10 (about 28cm per pixel) once MRO is done areobraking and in its final orbit, which should happen around October.

Finally, ESA's Venus Express is preparing for orbital insertion tomorrow. I only hope the Venus Express team can pull off the tricky maneuver as gracefully as did the MRO crowd last month.

More: The Venus Express orbital insertion appears to have gone off without hitch. VE will now tighten its orbit during the course of 16-orbit/26-day period (the process will go much faster for VE than MRO due to several factors, including Venus's more substantial gravity well). VE's final orbit, which should be reached on May 7, will be highly elliptical with the craft cycling between 60,000km and 250km from the planet. Along the way to final orbit, there should be several windows for initial observation, which means we should begin seeing data from VE in the next few weeks. Once final orbit is achieved, a few weeks will be dedicated to the commissioning of instruments. Afterwards, VE's mission begins in earnest on June 4. Congratulations to the ESA and VE team on a tough job done well.

Sunday, April 09, 2006

Happy Anniversary

Three years ago, Saddam fell. Wow. It seems like just a few weeks ago we were celebrating the third anniversary of the initial invasion. Oh yeah, we were . . .

Here's to the mighty. Here's to the brave. Here's to the fallen for all that they gave. God bless them who do great things.

Don't miss the gold star guest posts around the blogosphere today.

Saturday, April 08, 2006

The Nuclear Option

If reports are to be believed, the United States is actively considering a tactical nuclear weapons strike on Iranian atomic weapons facilities. Sadly, though, reports are rarely to be believed. And Seymour Hersch is never to be believed. When you read the article, what you get is routine contingency planning:
Some US military chiefs have unsuccessfully urged the White House to drop the nuclear option from its war plans, Hersh writes in The New Yorker magazine. The conviction that Mr Ahmedinejad would attack Israel or US forces in the Middle East, if Iran obtains atomic weapons, is what drives American planning for the destruction of Teheran's nuclear programme.

Hersh claims that one of the plans, presented to the White House by the Pentagon, entails the use of a bunker-buster tactical nuclear weapon, such as the B61-11, against underground nuclear sites. One alleged target is Iran's main centrifuge plant, at Natanz, 200 miles south of Teheran.

Of course the President won't "drop the nuclear option." We never take any option off the table. And the notion that Pentagon war planners are -- gasp -- drawing up war plans for all possible contingencies is, not to put too fine a point on it, far from shocking.

Look, if we decide we need to do something militarily -- which we very well may -- we need to do it effectively. If, given the location, design and construction of the Iranian facilities, the only effective means are TNWs, well, them's the means we'll have to use. Suffice to say, we are many, many mega-parsecs from taking that decision. If, however, there's a bit of concern in Iran tonight: Good. We're not looking to play Florence Nightingale here.

Thursday, April 06, 2006


The night is April 3, 1989. April 2 had been one of the first of the strange days that would follow – not immediately – but follow nonetheless. Pittsburgh, Pennsylvania, indeed, Pennsylvania period had always brought something special out of the band. The fans were always too numerous for the venue, the weather pretty near always sucked, and the local constabulary always turned out. All in all, a bid mix. There was plenty of trouble the first night. My traveling partner wound up in the pokey (though for an unrelated offense – driving a death trap of a VW bug we bought for 50 dollars and in the Omni parking lot, which was necessitated by our having busted our steering wheel/column while trying to unlock it in the absence of keys well mislaid). Not to worry -- we had him bailed out in time for the first night at Ann Arbor two days later -- and they gave us back the death trap to boot.

Any way. April 3 was better and, true to form, we got a little something special: a Bertha that brought the house down when nobody could determine precisely where the song should end. If inclined, grab the two shows from iTunes (GD Download Series Volume 9), it won’t sound better anywhere else. Or, if you prefer, check the Brertha out here before you buy the shows. Plenty of other nuggets here as well. Good stuff.

Wednesday, April 05, 2006


Remember these guys?

There was a time when they didn't look even this rough. Bedazzled has the (pre-Sid) footage. If you are of a certain vintage, it will light the corners of your mind. Misty, watercoloured, and all that toss. Piss off.