[F] New York Times on the Web Forums  / Science  /

    Missile Defense

Russian military leaders have expressed concern about US plans for a national missile defense system. Will defense technology be limited by possibilities for a strategic imbalance? Is this just SDI all over again?

Earliest MessagesPrevious MessagesRecent MessagesOutline (7710 previous messages)

lunarchick - 09:27am Aug 1, 2001 EST (#7711 of 7773)

A guy told me his 'grandpa' was an alcoholic, married to a Mary Booth (way back) - whose brother William Booth then saw the need to look after alcoholic men. His grandpa emigrated to Oz and lived 'out of town' and away from alcohol.

A tv documentary film tonight re Russia and an Alcoholism-culture, showed the need for them to take alcohol abuse seriously. Tightening up on underage sales, the quality of the brew, and generally c h a n g i n g the culture so that alcohol is not seen as the 'norm'.

rshowalter - 03:00pm Aug 1, 2001 EST (#7712 of 7773) Delete Message
Robert Showalter

MD7693 rshowalter 7/31/01 9:55pm asked gisterme to clarify a question of antecedants on a situation where we seem to be in contradiction with each other. br> MD7671gisterme 7/31/01 8:34pm MD7672 rshowalter 7/31/01 8:38pm

I'd said that, though the lasar and guidance image system resolution of lasar "space weapons" might eventually match the Hubble Space telescope's wonderful resolution, that wasn't " nearly good enough for some of the "death ray" schemes people seem to have been imagining, and drawing pictures about, and writing about without considering the numbers.

I cited space telescope images, which show stars as blobs of light. dec97-hubble butterfly and said

"The stars are so far away, that they are essentially point sources -- with angles like 10e-12 radians -- -- the imperfection of the optics smears them into "blobs" with a resolution of 5 x 10e-7 radians, or "worse." And that just isn't good enough for a "death ray" in space. The death ray idea makes sense (if you don't remember about reflective coatings) if you forget the resolution numbers. But the numbers rule that dream out.

" gisterme has argued that, for "point sources" that are intense enough, the geometrical issues don't hold, and don't limit what can be destroyed. MD6695 gisterme 7/6/01 3:10pm

"But that's wrong.

gisterme responded

"...But that's wrong...."

"Is not!"

Let's consider two targets, each emitting the same amount of light. One, from the distance to a telescope, subtends .2 microradians of arc, the other is .2 nanoradians of arc -- so one "bulls eye" is a million times larger than the other but to the telescope the tow sources look exactly the same, because both are well below the optical resolution that can be resolved.

Now, what gisterme is saying is that two "targets" --- are equally easy to destroy with a "perfect" lasar beam.

The bulls eyes are of very different sizes.

The difficulty of hitting them is in proportion to their area --- and, above a threshold, has little to do with source intensity for a lasar weapon.

gisterme, have you ever done any shooting?

As targets get smaller in area, they're harder to hit.

gisterme , if I understand what you're saying, then what you say is ridiculous.

Are you somehow saying something else? If so, what?

rshowalter - 03:03pm Aug 1, 2001 EST (#7713 of 7773) Delete Message
Robert Showalter

These responses deal directly with gisterme's MD7071 :
MD7136 rshowalter 7/17/01 12:05pm ... starts: . . .

"In MD7107 gisterme 7/16/01 9:24pm .. gisterme cites a number of references to dispute a statement of mine -- which was that the lasar programs, as weapons systems, don't work at all.

They are lasars. They are technically impressive in some ways. But they are not effective as weapons.

They are ineffective because of inescapably inadequate resolution in the radar and light optics systems taken as a whole.

They are ineffective because of inescapably inadequate adequate controls, for the system as a whole.

And, in addition, and most decisively, they are ineffective because it is easy to immunize missiles and reintry vehicles with optical coatings with reflectivity greater (and much greater) than 99% at the wavelength of the lasar.

I don't see how anyone who knows how reflective coatings work, and how easy they are to make, can continue to want to support lasars as serious weapons. But each of the other objections, taken alone, is also fatal.

The technical details are set out in the posts directly, which also access extensive prior discussions that I thought were clear.
MD7137 rshowalter 7/17/01 12:08pm
MD7139 rshowalter 7/17/01 5:24pm ... MD7140 rshowalter 7/17/01 5:25pm
MD7141 rshowalter 7/17/01 5:26pm ...

I believe these passages are clear and correct. The arguments could be more vivid, and clearer to more people, if they were set out with the sophistication that a courtroom lawyer would want, and would be able to get from a good illustrator MD7653 rshowalter 7/31/01 2:54pm

But the arguments are clear now. And I believe, right.

The weaponization of space is a big international issue, and technical matters involved here matter. There are some similar matters, connected to "smart rocks" or "brilliant pebbles" that also matter.

gisterme , I'd appreciate your comments.

More Messages Unread Messages Recent Messages (60 following messages)

 Read Subscriptions  Cancel Subscriptions  Search  Post Message
 Email to Sysop  Your Preferences

 [F] New York Times on the Web Forums  / Science  / Missile Defense

Home | Site Index | Site Search | Forums | Archives | Shopping

News | Business | International | National | New York Region | NYT Front Page | Obituaries | Politics | Quick News | Sports | Science | Technology/Internet | Weather
Editorial | Op-Ed

Features | Arts | Automobiles | Books | Cartoons | Crossword | Games | Job Market | Living | Magazine | Real Estate | Travel | Week in Review

Help/Feedback | Classifieds | Services | New York Today

Copyright 2001 The New York Times Company