From: skunk-works-digest-owner@harbor.ecn.purdue.edu To: skunk-works-digest@harbor.ecn.purdue.edu Subject: Skunk Works Digest V2 #70 Reply-To: skunk-works-digest@harbor.ecn.purdue.edu Errors-To: skunk-works-digest-owner@harbor.ecn.purdue.edu Precedence: bulk Skunk Works Digest Wednesday, 3 February 1993 Volume 02 : Number 070 In this issue: Re: KH-9/JC-130 Re: KH-9/JC-130 Re: KH-9/KH-11 Re: KH-9/KH-11 Re: KH-9/KH-11 Re: Different Shape Required Re: Different Shape Required Re: KH-9/KH-11 See the end of the digest for information on subscribing to the skunk-works or skunk-works-digest mailing lists and on how to retrieve back issues. ---------------------------------------------------------------------- From: dnadams@nyx.cs.du.edu (Dean Adams) Date: Tue, 2 Feb 93 03:16:21 MST Subject: Re: KH-9/JC-130 Rick writes: >dean wrote: >>The last KH-9 was launched about the same time. >>That must have put them out of the space business. I did some checking, and it seems that the last KH-9 bird ceased operating around 11/84... although one was thought to have been destroyed during a Titan 34D launch failure in 1986. >Well, the Manned Orbital Laboratory was supposedly going to be the >KH-10, and the KH-11 was, from what I recall, able to dump it's data >digitally to a ground station, Right, KH-11 and Advanced KH-11 use all-digital imaging systems. No more pesky "film capsules" to worry about, not to mention having to worry about *running out* of film. It also gives the KH-11 birds YEARS of orbital life, compared to mere months for KH-9s. Now they can keep going until the propellant runs out. >so the KH-9 was probably the last to have capsules to be recovered. It seems that way... >At least that's what I recall from _Deep Black_. Yea, although he did also say the SR was a Mach 4+ 100K+ ft a/c. :-) - -dean ------------------------------ From: Jan Mattsson Date: Tue, 2 Feb 93 12:02:58 +0100 Subject: Re: KH-9/JC-130 Dean writes: >Right, KH-11 and Advanced KH-11 use all-digital imaging systems. >No more pesky "film capsules" to worry about, not to mention having >to worry about *running out* of film. Now you have to worry about running out of encryption keys instead... ;-) ------------------------------ From: Rick Lafford Date: Tue, 2 Feb 93 08:12:05 EST Subject: Re: KH-9/KH-11 Dean writes: >Right, KH-11 and Advanced KH-11 use all-digital imaging systems. >No more pesky "film capsules" to worry about, not to mention having >to worry about *running out* of film. Are you sure the KH-11 uses an "all digital" imaging system and is that the only imaging system it has? Digital imaging is fair from an image quality standpoint but still doesn't approach silver halide technology. Kodak currently manufactures the largest megapixel imagers in the world and they are sold exclusively to the military. I've seen the output (can't remember how many millions of pixels) but I wouldn't want to go into battle based on the images collected by one. Regards, Rick - ----------------------------- Rick Lafford Eastman Kodak Co. lafford@clpd.kodak.com ============================================================================= ------------------------------ From: lhawkins@annie.wellesley.edu Date: Tue, 02 Feb 93 09:29:37 -0500 Subject: Re: KH-9/KH-11 In your message dated: Tue, 02 Feb 93 08:12:05 EST you write: > >Digital imaging is fair from an image quality standpoint but still doesn't >approach silver halide technology. Kodak currently manufactures the largest NOTE: This is not a flame, just a difference of opinion! Uhh, are you sure? Which imager are you talking about, and how long ago was it that you saw output from it? I've seen images from 4096x4096 pixel square ccds with 7.5x7.5 micron pixels (from Loral) and the images are indistinguishable from a photo on fine-grain b&w. The Kodak chips, at 9 microns/pixel, shouldn't be much worse. Also remember that since most of these ccds read out at 16 bits/pixel, it takes at least 16 film 'grains' to equal 1 pixel. I don't remember the size of a silver halide crystal, but I bet 16 of them is around 7.5 microns, and if so, the spatial resolution should be theoretically the same. Might you have seen images from an imager with either big pixels (>15 microns), 12-bit or less digitization, or both? Just wonderin' - --Lee ________________________________________________________________________________ R. Lee Hawkins lhawkins@annie.wellesley.edu Department of Astronomy lhawkins@lucy.wellesley.edu Whitin Observatory Wellesley College Ph. 617-283-2708 Wellesley, MA 02181 FAX 617-283-3642 ________________________________________________________________________________ >megapixel imagers in the world and they are sold exclusively to the military. >I've seen the output (can't remember how many millions of pixels) but I What form was the output in? In other words, how many grey levels and pixels was the *output* device that you were viewing capable of? If not well matched to the detector in both respects, the output could easily have appeared 'poor'. >wouldn't want to go into battle based on the images collected by one. > > Regards, > Rick > >----------------------------- >Rick Lafford >Eastman Kodak Co. >lafford@clpd.kodak.com >============================================================================= > ------------------------------ From: dnadams@nyx.cs.du.edu (Dean Adams) Date: Tue, 2 Feb 93 07:59:31 MST Subject: Re: KH-9/KH-11 Rick Lafford writes: >Are you sure the KH-11 uses an "all digital" imaging system and is that the only imaging system it has? I have heard that some of the very first KH-11 series may have carried some auxilliary "film capsule" capability, but this was way back in the late 70s when the first KH-11 was launched. Since then, they have been "all digital", at least in the sense that images are returned via a downlink and not "film"... >I've seen the output (can't remember how many millions of pixels) but I wouldn't want to go into battle based on the images collected by one. Oh, well. We have been doing *exactly* that for quite some time now. The vast majority of such intel data comes from satellites these days. At over 1 Billion a piece, I would hope they could take a nice pic. :-> - -dean ------------------------------ From: gtephx!rakoczynskij@enuucp.eas.asu.edu (Jurek Rakoczynski) Date: Fri, 29 Jan 93 14:36:02 MST Subject: Re: Different Shape Required > Date: Fri, 29 Jan 93 11:00:51 PST > From: I am the NRA > Subject: Different Shape Required > > >Timberwind was a project intended to create an NTR-powered heavy-lift > >launch vehicle for carrying heavy SDI payloads into space. The project > >began in the mid-1980s with the design and construction of a new type of > >NTR engine, the Particle-Bed Reactor (PBR). The PBR is a variation on the > >solid-core NTR in which the fuel elements (carbon-coated uranium oxide) are > >machined into .05mm-diameter spheres instead of hexagonal fuel rods > >as in the NERVA. Since the sphere has the greatest surface area relative to > >volume of any shape, > ahhhhh, the sphere has the _least_ surface are relative to volume.... > > >the PBR core has a much larger radiating surface than a conventional core, > >which in turn exposes more reaction mass to the radiation and, as a result, > >increases both thrust and I. Some speculations: You are right about a sphere having the least surface area, but I think for the application, it may present the most surface area. The description above reminded me of a Heat Transfer Module design of a few years ago. Some of you may remember. It was the size of a 2 pound coffee can with a central pourous ceramic heating element with a gas/air mix burning within the ceramic. The outer wall of the design was approx 2" thick consisting of 2 layers of ~1/2" tubes (were water would flow through) and surrounded by small ballbearings, to induce turbulance of the exhaust flow and maximize heat transfer to the water filled tubes. The ball bearing/water tube matrix wall was ideal for heat transfer and the balls "packed together" ideally, but proved to be expensive to manufacture. Finally they went to a conventional tube/fin arrangement and had to increase the size of the wall area to compensate for a less efficient design. - -- Jurek Rakoczynski, AG Communication Systems, POB 52179, Phoenix, AZ. 85072 UUCP: ...!{ncar!noao!enuucp | att}!gtephx!rakoczynskij Voice: +1 602 581 4867 Inet: gtephx!rakoczynskij@enuucp.eas.asu.edu Fax: +1 602 582 7111 Inet: JUREK.RAKOCZYNSKI@gte.sprint.com ------------------------------ From: gtephx!rakoczynskij@enuucp.eas.asu.edu (Jurek Rakoczynski) Date: Fri, 29 Jan 93 14:36:02 MST Subject: Re: Different Shape Required > Date: Fri, 29 Jan 93 11:00:51 PST > From: I am the NRA > Subject: Different Shape Required > > >Timberwind was a project intended to create an NTR-powered heavy-lift > >launch vehicle for carrying heavy SDI payloads into space. The project > >began in the mid-1980s with the design and construction of a new type of > >NTR engine, the Particle-Bed Reactor (PBR). The PBR is a variation on the > >solid-core NTR in which the fuel elements (carbon-coated uranium oxide) are > >machined into .05mm-diameter spheres instead of hexagonal fuel rods > >as in the NERVA. Since the sphere has the greatest surface area relative to > >volume of any shape, > ahhhhh, the sphere has the _least_ surface are relative to volume.... > > >the PBR core has a much larger radiating surface than a conventional core, > >which in turn exposes more reaction mass to the radiation and, as a result, > >increases both thrust and I. Some speculations: You are right about a sphere having the least surface area, but I think for the application, it may present the most surface area. The description above reminded me of a Heat Transfer Module design of a few years ago. Some of you may remember. It was the size of a 2 pound coffee can with a central pourous ceramic heating element with a gas/air mix burning within the ceramic. The outer wall of the design was approx 2" thick consisting of 2 layers of ~1/2" tubes (were water would flow through) and surrounded by small ballbearings, to induce turbulance of the exhaust flow and maximize heat transfer to the water filled tubes. The ball bearing/water tube matrix wall was ideal for heat transfer and the balls "packed together" ideally, but proved to be expensive to manufacture. Finally they went to a conventional tube/fin arrangement and had to increase the size of the wall area to compensate for a less efficient design. - -- Jurek Rakoczynski, AG Communication Systems, POB 52179, Phoenix, AZ. 85072 UUCP: ...!{ncar!noao!enuucp | att}!gtephx!rakoczynskij Voice: +1 602 581 4867 Inet: gtephx!rakoczynskij@enuucp.eas.asu.edu Fax: +1 602 582 7111 Inet: JUREK.RAKOCZYNSKI@gte.sprint.com ------------------------------ From: Rick Lafford Date: Tue, 2 Feb 93 14:31:48 EST Subject: Re: KH-9/KH-11 Phew! Nice to see everyone is awake out there :-) No flames taken (or meant). My question was centered around the " all digital" comment rather than the hybrid film/digital systems. The image was made on film which was developed and then scanned by a micron range CCD line imager. The resulting digital data was then downlinked to the surface. All the exposure I had to these programs evaporated in the 1980 time frame, so I don't know what the current level of the technology is. Thank you Lee for the very lucid discussion on the current state of the art. > What form was the output in? In other words, how many grey levels and >pixels was the *output* device that you were viewing capable of? If not >well matched to the detector in both respects, the output could easily >have appeared 'poor'. Good question. I'm not sure of either value but I ASSUMED that the group responsible for the detectors would use the correct display. (the other)Rick ------------------------------ End of Skunk Works Digest V2 #70 ******************************** To subscribe to skunk-works-digest, send the command: subscribe skunk-works-digest in the body of a message to "listserv@harbor.ecn.purdue.edu". If you want to subscribe something other than the account the mail is coming from, such as a local redistribution list, then append that address to the "subscribe" command; for example, to subscribe "local-skunk-works": subscribe skunk-works-digest local-skunk-works@your.domain.net To unsubscribe, send mail to the same address, with the command: unsubscribe skunk-works-digest in the body. Administrative requests, problems, and other non-list mail can be sent to either "skunk-works-digest-owner@harbor.ecn.purdue.edu" or, if you don't like to type a lot, "prm@ecn.purdue.edu". A non-digest (direct mail) version of this list is also available; to subscribe to that instead, replace all instances of "skunk-works-digest" in the commands above with "skunk-works". Back issues are available for anonymous FTP from harbor.ecn.purdue.edu, in /pub/skunk-works/digest/vNN.nMMM (where "NN" is the volume number, and "MMM" is the issue number).