3 September 2008 LOIRP Status

Dennis Wingo: Progress has been good since the last report. We have obtained audio from tapes from all of the ground stations, from Woomera, Goldstone, Madrid, as well as from NASA Langely where some of the tapes were re-recorded, which brings up and issue to discuss in a minute. What we have proven in playing audio and video data from these random tapes is that we can conclusively state that one of the two questions that were paramount at the beginning of the project (are the tapes any good), can be conclusively answered affirmative. Audio clips will be put on the net with a link. I think that they will fit in this email without overcoming anyone’s mail box. You already have the Woomera tape.
— This audio excerpt is from a tape being recorded at Goldstone wherein the tech talks about “seeing some sky” i.e. deep space above the moon’s horizon http://images.spaceref.com/news/2008/goldstone-g3-58lo3.mp3
— This audio excerpt from a data tape has features a technican with a spanish accent recording identifiying information on a tape being downlinked in Madrid. http://images.spaceref.com/news/2008/loirptest08madrid.mp3
We continue to find small problems with the drive. Most of them now is because the pins on the back of one of the connectors has many broken coax wires and it is taking a while to track down but we almost have a fully locked up video signal that we have recorded on a new test tape that Ken brought in. We are still looking for information and this past week we received many aperture cards, some of them with procedures on them that we are applying to align the electronics and mechanics of the drive.
Also, since we know that we are going to have the money soon for the head refurbishment, I have delayed some expenditures to expedite the head refurbishment. We have sent a large check and two heads (they have three heads now) to VMI to get them started with the refurbishment process and they are getting started.
We expect to receive by the end of the week, refurbished pinch rollers that are critical to the tape moving at the proper speed through the tape transport system. This week we sent a sample of the belts for the motors to a company in New Jersey and they are going to be able to make brand new belts for the reel motors and the capstan drive motors. It will take them about 6 weeks to provide us with new belts but the cost is fairly modest, about $1k for all the belts that we need, made from scratch, along with plenty of spare belts. That is the good news. However, not all news in this area is good.
A couple of weeks ago we sent the capstan motors and the reel motors from the two parts donor drives to get the bearings replaced. We have received their estimate of the costs. It is going to cost about $30k to get the primary and secondary drive motors completely refurbished. Ouch. This is not completely unexpected as the bearings are not the typical ones you buy at Auto Zone for a V-8 engine. They are bearing with the highest quality classifications in the books. They require being dunked in liquid nitrogen to remove or install, a rubber mallet just won’t do. So, we are holding off in this area for now though we will pay the $3k needed just to order the bearings that we need so that if we go forward to full production, we won’t loose any schedule there.
We are growing very concerned now on the schedule for the demodulator and are monitoring the progress there. We are also looking at our alternative for software demodulation or other hardware solutions. We are still investigating whether or not the demodulator on the drive is one that we can use. Still not sure and are still investigating. It will take us fixing a couple of final problems with the electronics before we know for sure.
One thing that we found this past week is a tape from Langley that is of the famous shot of the Earth from the Moon. This tape looks like it may have been demodulated prior to writing back out to the tape. We are writing the software now in Labview to record this data and put it back together and see if it is that image. If it is, and if the tape is demodulated already, we will know for sure whether or not the tape drive is fully functional for an entire hour of playback, which is different than a few minutes of audio. If we can do this, then we will have met our next major milestone of proving that the drive can be refurbished to the point of reliably playing a tape back.
The demodulator is external to the drive (assuming for a second that the on board demodulator is not the right one) and so we will be able to show that the drive is fully operational. The system, which is the tapes, the drive, the demodulator, the software, and the computer is in progress and we will at least put to bed the continuing issue of exactly what the bandwidth of the original signal from the spacecraft was.
We are also trying to contact Lee Scherer, who was the Lunar Orbiter program manager for NASA and the former center director of Dryden and KSC. We are trying to track down some Boeing people who were working on the ground support equipment at that time to ask some questions.
Audio and pictures attached.

19 August 2008 LOIRP Status

Keith Cowing: We have a milestone to report tonight. We put a real LO-II tape on the drive with the known good head and was able to get audio and the test video patterns off the machine. We did not dare go far enough yet to get the LO image but here for your listening pleasure and verification of milestone, is a voice that has not been heard since November 30, 1966. Sorry but if you have a PC you may not be able to hear it but on the Mac it is great! [Audio file] Also a pic to go along with it.
We are closing in on the prize.
[Audio files of voice track: PC (.wav) Mac
“30 November 1966”
Here is a MP3 version (thanks Ken!)

19 August 2008 LOIRP Status

A lot of mundane yet important milestones.
Dennis Wingo: We have now confirmed that the timing system on the drive for the servos and just about everything else, is back into original specifications. We found in one of the manuals that we have, the procedures for aligning the various systems of the drive. Though the other three FR-901/902’s are a little different, it is close enough that we now have verified this most critical system. We tested and confirmed that the oven controlled temperature stable clock reference (two out of three that we have tried) is within 6 x 10-8 Hertz, or better than one part in one million. This was a critical thing to find as if the system clock standards had been out of tolerance (after tweaking and 24 hour test), we would have had to have found an alternate means of providing a stable signal to the machine(s).
Fortunately as we were concerned about the possibility, we asked the ever intrepid Mark Newfield if he knew were a ultrastable 1 Mhz oscillator might be found. After a search with Ken Zin, one was located, from about the same era as the drives! We brought it over and it is hooked up and up to temperature and operating fine as a backup to the in machine standard.
Ken went through all of the rest of the timing system, and after replacing a bunch of transistors, the entire timing chain is within specification. This has had a beneficial effect on the servo system and even with the known bad bearings the servos that control the reel motors are within specification for testing at least. We still have out the reel motors and the capstan motor for bearing refurbishing. We have found more documentation in the manuals with details about the mechanical specifications of the servo system and its motors. We are anxiously awaiting the aperture cards that we are getting copied to see what other documentation that we now have from the former Ampex head of field engineering.
We have been digging into the software issues associated with the data acquisition card. At this time I can get it to digitize at 1.8 million samples per second, not good but better than before. It is going to take a lot of digging into and creating our custom software for the data acquisition and storage task. I am still looking at an alternative that I may pull the trigger on this week.
We have reorganized the work space and created an area for the computer that will be connected to the drive to reside, close enough for the hook up. With all the work that we have done and with this much verified, and knowing that the likelyhood of a tape being damaged was nil, we put a Lunar Orbiter tape on the drive Friday. There is a very good reason for this even before the system is fully back within operating specifications. The reason is that the servo system needs a tape with a 500 kHz pilot tone on it to come fully into lock. To make a new one means that the record and playback system has to be fully back into specification, which it is not as of yet.
So we took a LO tape and put it on the drive to examine the test data at the front of the LO tapes. With this we can get the best idea of how far we have to go (a ways still) before the drive is 100% back into its original specification. We will get back our rollers for the tapes this week. We can mount them and get the mechanics of the system fully back within original specification. The Capstan and Reel motors are still being worked on.
When we put the tape on, we did get video but the head that we were using is not the best one. There are still some problems in the time base corrector (for the tape, not the servo system) and other electronics but we have actually read multiburst off the oscilliscope (this does not mean that the demodulator is the correct one) from the tape. Pictures to follow and the video will be up on the facebook page in the morning.
We are also sad this week to lose our two students from San Jose state (Kenneth Willians and Austin Epps) this week as the fall term is restarting. They will be here part time (20 hours a week) to help out but their dedication and hard work this summer has really helped us with doing all the things we have had to do to make the progress that we have. Good job gentlemen! I am getting both Austin and Kenneth to talk to their professors about getting elective credit for working on the project. We did over 300 hours of this on my SEDSAT project at UAH for undergrads and would like to have the students do this here as well. I would posit at least one graduate level degree could come from this project as well, so we look forward to getting images soon!
We have also been monitoring the progress to get the $50k from Doug Comstock obligated and to get the head refurbishment going. We have found out that VMI has just had a big order come in so we might be a bit slow in getting our head back. Will know more this week

19 August 2008 LOIRP Status

Dennis Wingo: A bit delayed but we had a lot happen over the past few days, not all of it good.
We have had a bit of a setback. We have received our interim computer from Apple and it is almost the same as the final one, which alerted us to the problem, which is that the I/O bus is incompatible with the National Instruments data acquisition card that we have purchased, even though their website said it was supported. I should have looked closer and verified this. We can get a replacement card that will work but since the hardware is being shipped from Hungary, it would cause a 5-10 business day delay. This is unacceptable at this point so Austin Epps, one of our engineering students found a work around with a PCI-Express to PCI adapter (the new bus to the old bus architecture) so we have purchased this and I am putting him on a plane to San Diego to pick it up and bring it back. This is cheaper than it seems as the price for expediting this is $150 dollars shipping and handling and having him fly down there is only twice that and saves two days. So, this evening we will be able to put the new computer and the data acquisition card together. Kenneth Williams is loading the software on the computer today.
On the good news front, $50k of additional funding has been provided through Doug Comstock from the NASA IPP. This money will be used to pay for the tooling to refurbish our heads (which are somewhat different than the standard commercial heads) and to get a single head completely refurbished. To save money we are doing all of the pre-refurbish work ourselves here as the first thing that the company that is doing the refurb did when contacted, was to call Kenneth Zin, our technical lead for help!
However, this $50k brings its challenges. The head refurbishing company demands a check for 2/3rds of the cost of the tooling to begin work. Due to the way that NASA procurement works, this means that we would have a 30 day delay before being able to move forward with the head refurb. This is unacceptable to me so I made a command decision to cancel the purchase of the high end MacIntosh computer and we will keep the existing interim computer and do the initial image processing with it.
This is an easy decision to make, which saves us $10k of expenditure that we can use to pay the head refurb company right away and get reimbursed when the NASA money comes in for this task. Our image processing may happen slower but since our goal at this time is only a few images, this is not a big sacrifice. It will be ok for our other image processing as well for now. We can order the new computer after we are successful in getting our images and moving into production (should funding become available). The interim computer can then become the secondary computer to run the second drive. The head refurb is by far the highest priority
We have made a lot of progress on the machine as well this past week.
We have started the process of refurbishing the mechanical systems of the primary drive. Since the mechanics are exactly the same for all four machines, we disassembled the parts donor drives for their tape guides (pictures enclosed), capstan motor, and the reel motors. All of the bearings are 40 years old and have to be replaced. We can’t do this ourselves so we took them to a house in San Francisco that does this type of work as they have the tooling to do so. We took some of the simpler parts, along with some bearings that Kenneth Zin already had, to a place in South San Jose to be replaced and we will have those back this week and placed on the machine. Since there is setup time and charges to be considered here we have taken the step of taking two sets of all of the mechanical hardware to be done at once. One will be spares and if we are funded to go forward we will just put the spare hardware on the second machine. It is critical to get the mechanics properly aligned so that the tape transport system is back to the original specifications.
We have also shipped out additional rubber parts to redco in Nevada for refurbishing/replacement. One of these is easy, as it is the rubber pads on the tape reel assemblies that the tapes rest against. The second is not so easy, as we have to get the rubber interior surface of a seamless nylon set of belts that run the motors refurbished. We sent the belts off of the parts donor machines to get them refurbed first and then when we put the new stuff on, we will send the other belts to be refurbed. This is a major concern but doable as these belts are also critical to the proper operation of the entire servo mechanical system.
We have also had success the past week (after Fedex ground’s inability to find our building for four days) in obtaining a lot of schematics and technical data for the FR-900 drives. This came from a labyrinth of contacts that led us finally to the retired head of Ampex’s field engineering force! He happens to have most of the information that we need on the drives in terms of schematics, parts lists, and other details. We are still missing some procedures but we are much closer to having everything that we need and worst case we can get the drive completely back to specifications with what we have. This is truly an adventure in technoarcheology in finding this data. One wonders how different our civilization would be today if we had all of the documents related to the masterful feats of Greek mechanical engineering and Roman civil engineering today. Just think of the problems that NASA is having in recreating a 40 year old technology to return to the Moon!
We have also been testing in detail the 16 heads that we have. It looks like that we have at least one additional head that can be used as a test head for our alignment procedures of the drive. We have tested and proven the known good head but do not want to use it until we are ready to put a real Lunar Orbiter tape on the drive. Kenneth Williams and Ken Zin have built test fixtures that allow the heads to be tested and the 43 year old relays on the head module to be “cleaned” by exercising them with a signal input.
We have also visited the NASA Ames surplus and have found some useful test equipment, including a rig that allows us to splice tape. We found some 19″ racks for test equipment as well and some oscilliscopes. We also picked up an older MacIntosh to use as a server for the printer and our local kludged internet connection so it has been a good week on the scrounging front. Another device that we found is a reader for microfilm. We will use it to compare the images that I have on my microfilm of the Moon to guarantee a match for the analog data vs the film.
Andrew Gold, the CEO of one of the companies in the research park is going to set us up with a fat pipe internet connection gratis this week so this solves our issue of having to pay a NASA contractor $6k for what we were able to do for an $80 dollar piece of hardware.
Conclusion
So basically we are moving forward and working through our challenges! Lots and lots of work in a detailed manner that is necessary to bring the drives back to full operational status and get them back into their original specifications.
Pictures follow.

12 August 2008 LOIRP Status

After being away for a week and coming back I am very happy to report our current progress. The guys have done a marvelous job in turning the McDonald’s into a working laboratory. The fake planter in the middle of the room has now been turned into a nice working table for the testing of the hardware on the drives. They have also put together the wiring for power in the area in a manner that is safe and efficient for working. Pictures follow of this.
On the technical side, a lot of progress was made there as well. We have the second drive brought to functional status. Since we don’t have the money to replace all the parts we are not going much further but there are things that we can do with the drive to test parts and subsystems while the primary drive is being optimized for full operation. I am including an abbreviated video here but a longer one will be on the Facebook page of both drives operating at once.
Kenneth Williams has been testing all of our heads and it may be that we have more than the one good head. There are electronics that have degraded that may need replacing but there is no reason that we can’t get more than one head operational. We have verified that the known good head is in very good shape so we are confident of it when we actually put a real tape on the drive.
We have ordered and the parts are on the way for the Data Acquisition system as well as our image analysis software. We are doing an interim solution for our computer by renting one from the ODIN system here at Ames in order to maintain our schedule and our progress rate.
We are still on track to have a real Lunar Orbiter tape on the drive by the end of the month and we will continue to update you all on our progress. I cannot say enough good about the competence of Ken Zin and the enthusiastic participation and hard work of our students. We are going to be talking to their faculty advisors about them obtaining engineering credit for their work as it has been a very good lesson in overall engineering design and real world experience.

4 August 2008 LOIRP Status

Dennis Wingo: The project is moving forward. We have found a source (former Ampex Field Engineering Head) of further documentation for the drives. We are working out how to get this information to us this week. I have also added Charlie Byrne to our mailing list here as he is the original progenitor of our entire project with his 1965 memo regarding the utility of the analog data. Charlie has graciously offered to help and has a funded LASER contract relative to the film.
When we get images we will be sharing them with him for analysis. We have almost completed replacing the power supply capacitors (except for a shipment that got sent to my office in Alabama rather than to the lab in CA) and we have found procedures whereby we have calibrated the power supplies. Pictures of the machine with updated parts to follow.
We have a quote and timeline from VMI on the heads and are anxiously awaiting any word on the funding for the heads. We have sent the pinch rollers ( a mechanical drive component for the Capstan drive made of rubber) to a refurbishment house and will have a quote for that this week and have them back in about two or three weeks.
The folks at JPL have been incredibly helpful as well and have set up a private website for us that has everything that we need for our submittals to the Planetary Data System. Thanks to Sue Lavoie and the folks down there for being incredibly responsive.
We have our known good head and we have found two others that are in good enough shape to use for testing of the machine.
Kenneth Williams figured out a great way to mount smaller new caps where the big caps went.
We are also beginning debug and alignment procedures for the drive’s subsystems this week.
I am in Alabama this week and will be back on the evening of the 11th.

29 July 2008 LOIRP Status

Dennis Wingo: I am doing another one today because a lot of things happened. First of all the students and Lynn Harper’s kids came in today and got 90% of all of the tapes out of the boxes and properly categorized. This is a major milestone that Keith enabled. Some of the students have volunteered to come in on Thursday to finish the job. After Pizza everyone was happy that they helped today.
We also received a lot of capacitors today and replaced a lot of parts in the machines. Every part that we replace and update like this makes the machine more stable in operations and function. Following will be pictures of the 90 volt Capstan power supply before and after the new caps. The newer ones are a pretty blue color.
Third, Ken Zin reached another technical milestone tonight by fixing a connector problem that we had that shorted out several signals. After one broken pin that was routed around with coax, the machine powered up and the servos are now locking into synchronization with their control signals, a major milestone to get a real tape to play. A picture of the monitor and the scope displaying the multiburst signal off of the test tape is shown tonight.
We expect a lot more parts tomorrow and Thursday that will be installed in power supplies and starting to replace them on some of the circuit cards. We have a long way to go, but we have also come a very long way. The students will be active tomorrow replacing parts in the machine as well as with a set of spares for the machine. Having known good working spare parts is critical to keeping downtime to a minimum once tape operations are underway on a daily basis. The machines are designed for rapid servicing and all of the students are learning the ins and outs of the machine.
We lament that we will be losing James as he, along with Austin and Kenneth, are doing a great job. I also want them to refurbish the spare vacuum pump and other key parts that will be used as spares and for possible components for the possible second machine. Ken is pretty confident that if the funding is made available that we can get a second drive up and running which could almost cut in half the time for doing the digitization of the images.
We have been hard at it for almost a month now. Ken is taking two days to go to Yosemite and I will be going home for one week next week. I will be back on the evening of the 11th.

28 July 2008 LOIRP Status

Dennis Wingo: The project is rolling on. We have had some good progress on many fronts. Today we had a telecon with JPL (Rafael Alanis and Steven Adams) about the metadata tagging for the images produced from this effort. It was a good telecon and we expect to receive the templates and other information that will allow us to put together the images in the format that will properly integrate with the Planetary Data System.
We also had a major breakthrough today from a friend of a friend of a friends friend for finding documentation for the Ampex FR-900 that is our best drive that we have been working on and operating for the last couple of weeks. A former field service manager from Ampex was found who has the critical schematics and assembly drawings stored on Aperture cards (microfilm on a Hollerith punch card). We have sent him our assembly numbers from our equipment and he is getting a quotation for printing and digitizing the data. We will also have the one document from the Stanford Ampex archive by early next week. Therefore we are reasonably confident that we will have sufficient documentation to fully return to operation the primary FR-900A drive that we have been working on.
Today though, since Ken is troubleshooting individual circuits on the drive and this is not amenable to three or four people working on that simultaneously, I have tasked the students to shift around working with Ken and to completely disassemble and clean the second best drive, an Ampex 901 (that we now know was designed and built especially for the USAF and Eglin AFB) drive that we already have all the documentation on. We have repaired this drive with the top frame from another drive (pictures enclosed) and have washed the drives power supplies and other subsystems. We will attempt to return it to minimal operational status this week as we have time, while focusing on the primary FR-900A drive.
If the follow on funding is obtained to refurbish the heads and the operations, it is our hope that we might possibly have two operational drives (NO PROMISES) which would shorten the time to digitize the images. We will know within a week or two whether this path makes any sense.
Troubleshooting is beginning in ernest now with Ken tracing out circuits. He has found a couple of problems that have been fixed and more that are in process. This is just a very detailed, circuit by circuit process. We have ordered several thousand dollars worth of parts in the last few days and some have already been received and installed. Note in the latest pictures the blue capacitors that are replacing the silver ones. The newer ones are generally much smaller for the same capacitance so some machining of sleeves to make up the difference will be required. Pictures follow.
Tomorrow is tape inventory day with Keith Cowing leading the inventory team of students to get an accurate count of the tapes and then to sort and properly label all the tapes so that we can find the tape that we want when we want during the digitizing process.
All in all we are making steady progress and have reached all of our month one milestones and are well on the way with month two work.

23 July 2008 LOIRP Status

Dennis Wingo: It has been a very busy several days, especially the last two days with several visits by many people small and great. We have still managed to get some work done and we have a working head (not the good one but a least one that works, and we have been able to read RF off of the heads. The servos on the machine are having a hard time syncing up properly, which we knew was going to happen due to their advanced age. We are evaluating whether or not the servos from the drive next to the working one are the same configuration and if so (we think that they are), we will take them apart and refurbish them first. This allows us to use the working machine to continue to debug the electronics, speeding the overall effort.
In the next day or so we will be ordering several thousand dollars worth of detail parts that we have been cataloging from the electronics bays. Today we received enough large electrolytic capacitors that we were able to replace the filter caps in all of the card racks and then reinstall them, allowing us to bring the entire system back together. Basically this allowed us today to test the entire system’s power supplies (six big power supplies). We now have at least a full compliment of working power supplies and two known good spare power supplies. Last week we were able to replace almost all of the relays in the system so little by little, things are coming back together.
We have been able to run tape and with a set of heads that we found (worn but still serviceable) we have been running a test tape to begin the process of debugging the signal system.
Our team is now together with Keith leading the effort to properly catalog and sort the tapes for our initial inventory. We are peeling off one of our students to help him and some more students volunteered to help with the work today (at least four)
In another coup today, one of the U.S.G.S. scientists from Flagstaff came by today (Dr. Lisa Gaddis), and came away a believer. Lisa has been working with the film and they have been doing a great job and they have offered help us with the selenographic details of properly registering the images. Couple this with the help from JPL to metatag the data for the Planetary Data System and we have the critical elements that we need to properly integrate the images into the mainstream of NASA image databases.
On top of all of this Charlie Byrne, the scientist from Bellcom that wrote the original justification for NASA to use analog tape drives to preserve a higher quality dataset for Lunar Orbiter came by today. We have his original memo where he laid out the justification for the tapes and we printed this and got him to sign it. It will be preserved and presented to the right people a the right time as a gift. Charlie also signed the drive today! That was an amazing thing and we put his photo on our facebook page today.
Additionally, the Google Moon folks came by yesterday and are seriously considering at least some level of support. Eric Anderson and Peter Diamandis were also by today.

16 July 2008 LOIRP Status

Dennis Wingo: Ok, we have been sandbagging everyone just a little. We have been fixing and cleaning, and testing with power some of the subassemblies for the drive. We have also started reassembling the drive and for the first time since 1992 we have powered the drive up!!
Pictures to follow. However, everything is not all wonderful. We have started ordering parts and for some of them the lead time is weeks. This is going to slow down progress a lot soon. Also, there is a possibility that the drive that we have been working on may not be the one that we eventually return to working order.
The problem is that the documentation that we have is for the two older drives, not the much newer one that is in much better physical condition. This will cause a lot of problems in troubleshooting the newer drive if we can’t find the documents for the newer drive.
The drives originally came from Eglin AFB and we may try and see if they still have any documents or materials down there. We tried to call the contact person that we had from Eglin but he died last year. Ken Zin also called one of his contacts, who is in a nursing home and unable to help. We have called Ampex and tomorrow we will talk to the folks at the Stanford Ampex Museum.
There is a very large collection there and we may have to go dig in a warehouse to find the docs but it is a good possibility so all is not lost. This is how these projects go, part detective and part scrounging.
We are to the point where we can test some subsystems and will be doing more to do that over the next week or so.

Lunar Orbiter Imagery and Apollo Landing Site Selection

Source: Apollo Expeditions to the Moon Chapter 5.5 – Mapping and Site Selection
Meanwhile the third member of the automated lunar exploration team had already completed its work. The fifth and last Lunar Orbiter had been launched on August 1, 1967, nearly half a year earlier. When JPL and Hughes began to experience difficulties with Surveyor development, and with the Centaur in deep trouble, NASA decided to back up the entire proaram with a different team and different hardware. The Surveyor Orbiter concept was scrapped, and NASA’s Langley Research Center was directed to plan and carry out a new Lunar Orbiter program, based on the less risky Atlas-Acena D launch vehicle. Langley prepared the necessary specifications and Boeing won the job. Boeing’s proposed design was beautifully straightforward except for one feature, the camera. Instead of being all-electronic as were prior space cameras, the Eastman Kodak camera for the Lunar Orbiter made use of 70-mm film developed on board the spacecraft and then optically scanned and telemetered to Earth. Low-speed film had to be used so as not to be fogged by space radiation. This in turn required the formidable added complexity of image-motion compensation during the instant of exposure. Theoretically, objects as small as three feet could be seen from 30 nautical miles above the surface. If all worked well, this system could provide the quality required for Apollo, but it was tricky, and it barely made it to the launch pad in time to avoid rescheduling.

A photo of the crater on the Moon,Tycho

The youngest big crater on the Moon is Tycho, which is about 53 miles across and nearly 3 miles deep. These Orbiter V photographs reveal its intricate structure. (Area in the rectangle above is pictured in higher resolution below.) A high central peak arises from the rough floor, and the crater wall has extensively slumped. The comparative scarcity of small craters within Tycho indicate its relatively recent origin. Flow features seen in both pictures could have been molten lava, volcanic debris, or fluidized impact-ejected material. Surveyor VII landed about 18 miles north of Tycho, in the area indicated by the white circle above. Enlargements of these pictures show an abundance of fissures and large fractured blocks, particularly near the uppermost wall scarp.

Continue reading “Lunar Orbiter Imagery and Apollo Landing Site Selection”

Lunar Orbiter Missions – Table

Photographic Lunar Lunar Lunar Lunar Lunar
Parameters Orbiter 1 Orbiter 2 Orbiter 3 Orbiter 4 Orbiter 5
Launch Date 10-Aug-66 6-Nov-66 5-Feb-67 4-May-67 1-Aug-67
Periselene (km) 40.5 41 44 2668 97
Aposelene (km) 1857 1871 1847 6151 6092
Inclination (deg) 12 12 21 85.5 85
Period (h) 3.5 3.5 3.5 12 8.5,3.0
Impact date 29-Oct-66 11-Oct-67 10-Oct-67 31-Oct-67 31-Jan-68
Impact coordinates 7 N, 161 E 3 N, 119.1 E 14.32 N, 92.7 W ??, 22-30 W 2.79 S, 83 W
Acquisition dates 18-29 Aug 1966 18-25 Nov 1966 15-23 Feb 1967 11-26 May 1967 06-18 Aug 1967
Quantity of frames
High resolution 42 609 477 419 633
Medium resolution 187 208 149 127 211
Altitude range for photos (km) 44 – 1581 41 – 1519 44 – 1463 2668 – 6151 97 – 5758
Highest resolution
Periselene (m) 8 1 1 58 2
Aposelene (m) 275 33 32 134 125
Framelet width at periselene (m)
High resolution 200 170 185 11350 420
Medium resolution 1500 1300 1400 85100 3200