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[ 20070123 ]
Powell Workday; Keyholder At Last!
Before and after pictures of the quasi-annual cleaning (last Saturday morning) of the 30" main mirror of the Ruisinger telescope at Powell Observatory (click on pictures for full-size versions, 2288 × 1712):
(That mirror assembly, by the way, weighs a cool 253 lbs.) And I'm finally a keyholder, which means I've got the biggest telescope in 5 states to play with. Once they get it put back together, that is.
Powell is open to the public every Saturday night from May through October and can be reserved for private parties for a surprisingly (in my opinion, seriously underpriced) reasonable fee on almost any other night of the year. As noted above, since the main telescope is taken apart at the moment, visitors can look at it, but not through it. The Louisburg Community Telescope (actually two telescopes, a 16" and a 12½"), however, remains functional.
Jay Manifold [3:46 PM]
[ 20070116 ]
C/2006 P1 McNaught in Daylight?
I'm late to this, but reports are trickling in (from Mauna Kea, anyway) of successful daylight observations of the comet -- which, for Northern Hemisphere observers, is the only alternative since it has made perihelion passage and entered the south side of the sky.
Graze on over to SpaceWeather.com for a finder chart, to the Minor Planet Center for an ephemeris, and to Shadow & Substance (which just got a permalink) for the orbit, plus a phenomenal animation from SOHO, and a daytime finder chart for us terrestrial Yankees.
Jay Manifold [9:35 AM]
Fighting Bird Flu Without Vaccine
A fascinating article in The Scientist, When There Is No Vaccine, explains how; and the real-world application to malaria could save huge numbers of lives immediately, whether H5N1 becomes transmissible or not:
Virus infections each produce a specific immune response, and a subsequent infection by a virus of the same group produces not only a specific response to itself, but also a boost in immunity to the first. Therefore, because of these cross-reactions, a horse serially immunized against only two or three different viruses could produce a serum effective to treat a whole range of hemorrhagic fevers.
What's the catch? No surprises here: it's a ridiculously high regulatory barrier.
There is just one bureaucratic snag. US Food and Drug Administration rules promulgated in 2002 have stopped cold the progression to market of any new therapeutic product targeting a disease for which it is not ethically admissible to carry out human trials. What is widely known as the "two-animal rule" requires that instead, the product be tested in at least two different species, one of which should ideally be a non-human primate. As this requires Biosafety Level 4 animal containment facilities, the cost of complying with this measure outruns even the astronomical cost of human trials.
Will we experience another calamity on the scale of the Black Death due to bureaucracy? If we do, well, to quote Larry and Jerry, just think of it as evolution in action.
Jay Manifold [9:29 AM]
[ 20070110 ]
Give Me Tenure or Give Me Death
As Dave Barry would say, I am not making this up.
Jay Manifold [4:26 PM]
[ 20070109 ]
Graze on over to Dr Eric Flescher's E.O.A.S. for an observing report, and hit spaceweather.com for finder charts.
Locals, particularly those in the southwestern portion of the KC metro, may wish to use the following site for early evening observation, as described by David Young on the ASKC Yahoo! group:
Go west on 95th street from K-7. Continue past all of the road closed signs until you come to a tee intersection. Jog south a hundred feet or so and pull into the road. This is a housing development under construction so no traffic up that road. We had a couple of people stop by and ask what were up to but they left before we found the comet.
Go get it!
Jay Manifold [6:23 AM]
Plutoed. Heh.
Jay Manifold [6:23 AM]
[ 20070106 ]
Technical Note on Israeli Proposal
That would be this proposal, from which I quote:
If things go according to plan, a pilot will first launch a conventional laser-guided bomb to blow a shaft down through the layers of hardened concrete. Other pilots will then be ready to drop low-yield one kiloton nuclear weapons into the hole. The theory is that they will explode deep underground, both destroying the bunker and limiting the radioactive fallout.
Israel developed tactical nuclear weapons in the early 1970s for use on the battlefield. In an attack on Iran, its air force would be expected to use a low-yield nuclear device of 1 kiloton (equivalent to 1,000 tons of TNT), loaded on a bunker-buster missile.
“If the nuclear device explodes deep underground there will be no radioactive fallout,” said Dr Ephraim Asculai of the Tel Aviv Institute for Strategic Studies, who worked for the Israel Atomic Energy Commission for more than 40 years.
Professor Peter Zimmerman, a nuclear physicist at King’s College, London, was less sure. “The definition of low-yield nuclear weapons is not easy,” he said. “I assume that it includes any device which is less than 5 kilotons. If such a bunker-buster missile is exploded at 70ft below ground” — thought to be the minimum depth of the hidden centrifuges in Natanz — “some radioactive fallout is expected.”
We can check that. Turning to The Production and Dissolution of Nuclear Explosive Melt Glasses at Underground Test Sites in the Pacific Region (756 kB PDF), we find:
Rc = 100 (Y/h)1/3
where
Rc is the cavity radius in meters,
Y is the total yield in kilotons, and
h is depth of device burial in meters.
Setting h at 20 meters, we find that for a device yield of 1 kT, the cavity radius would be 37 m; and at 5 kT, it would be 63 meters.
So at these depths and yields, the explosions will not be even remotely contained. There would be some venting even if they were far deeper, but in this case, the bombs won't leave cavities, they'll leave craters hundreds of feet across -- and mushroom clouds.
Make no mistake: this is going to look really, really bad. Actual amounts of radiation might be modest -- extrapolating crudely from this diagram, which is for a weapon yield three orders of magnitude larger than those being contemplated, we may assume that a relatively small area (a few square kilometers) would get dosed, and the Natanz facility itself is remote from any substantial population -- but the visual images of craters and mushroom clouds will, for many people, overwhelm the reality that millions of lives would be saved by the attack.
Jay Manifold [10:20 PM]
-- or not; regular correspondent and contributor Ric Locke, last heard from, or at any rate last acknowledged, in the Old Geeks for Truth post of September '04 -- provides me with the following non-decimalized calculations:
The story says "the size of a golf ball" and about the weight of "...a can of soup."
A golf ball is almost exactly two and a half cubic inches. A can of soup is twelve ounces, or about a sixteenth of a stone. Working out the math for the density gives three and a half tons per hogshead, or seven tons per tun.
The result falls between iron (3-3/8 t/h) and nickel (3-3/4 t/h). The AP reporter, or someone being interviewed, has nice judgement for weights and measures, assuming that the object is in fact a metallic meteorite.
(metric system? what metric system? Of course, ideally I shouldn't mix units from the foot-pound-minute and furlong-stone-fortnight systems.)
Well, actually the golf ball-can of soup-orbital period of random meteoroid system should work pretty well in this application ...
Jay Manifold [2:39 PM]
[ 20070105 ]
I am quoted in Horseman of the Arcturcalypse Alan Henderson's Did Gerald Ford Really Heal The Nation?
Jay Manifold [2:34 PM]
[ 20070103 ]
Possible Meteorite Hits House in NJ
(NEWS FLASH, 20070105 1654 CST/2254 UT: Yep.)
See Metal object crashes through N.J. home; for earlier instances reported on Arcturus, see:
- Stony Meteorite Explodes Above Chicago
- The Great Chicago Meteor of 2003
- A Near Miss in Spain
- A Non-Miss in Iran
- Large Meteor Coincides With Terror Alert in Indonesia
UPDATE: OK, here's what I should have included the first time. The picture shows a brassy, oblong chunk of pitted metal 6 cm in its longest dimension and "weighing more than 13 ounces," ie ~370 g. Supposing its volume to be equivalent to that of a small brick, 6 × 3 × 3 cm, and dividing its mass into this, we get a density approaching 7 g cm-3. Turning to the helpful How To Identify a Meteorite, we find that iron metal is 8 g cm-3, so this is a reasonable value. In any case, a definitive analysis is to be performed in the next few days.
Jay Manifold [7:01 PM]
[ 20070102 ]
“I am calling for a New Contentism”
Jay Manifold [7:34 PM]
[ 20070101 ]
Have a listen to this and graze on over to ChicagoBoyz for a typically overwrought dose of sunny optimism from yours truly. Let's all get rich and save the world. Not necessarily in that order.
Jay Manifold [12:03 PM]
