Author Topic: Ranger 7 'Meets' the Moon  (Read 5328 times)

Offline catdlr

  • Member
  • Senior Member
  • *****
  • Posts: 4656
  • Marina del Rey, California, USA
  • Liked: 1472
  • Likes Given: 900
Ranger 7 'Meets' the Moon
« on: 07/29/2014 03:50 AM »
50th Anniversary

Published on Jul 28, 2014
The historic 1964 Ranger 7 mission was the first true success in the United States' early quest to explore the moon.

The JPL-built spacecraft launched July 28. Three days later, it made a targeted impact on the moon, sending back more than 4,300 photos along the way.

« Last Edit: 07/29/2014 03:51 AM by catdlr »
Tony De La Rosa

Offline alk3997

  • Full Member
  • ***
  • Posts: 380
  • Liked: 29
  • Likes Given: 27
Re: Ranger 7 'Meets' the Moon
« Reply #1 on: 07/29/2014 04:20 AM »
The written history of the Ranger program is at:
http://history.nasa.gov/SP-4210/pages/TOC.htm

It's an interesting read, particularly with the congressional investigations into the Ranger failures.  It's also interesting to read how much we didn't know (contamination procedures were required against spreading Earth pathogens onto the moon) and how primitive the electronics of the day were.  The final TV package was quite sophisticated for its time and pushed the other science experiments off of the final Rangers.
« Last Edit: 07/29/2014 04:22 AM by alk3997 »

Offline catdlr

  • Member
  • Senior Member
  • *****
  • Posts: 4656
  • Marina del Rey, California, USA
  • Liked: 1472
  • Likes Given: 900
Re: Ranger 7 'Meets' the Moon
« Reply #2 on: 07/31/2014 01:05 AM »
Lunar Bridgehead: The Ranger 7 Story

Published on Jul 30, 2014
Travel back to July 31, 1964, to NASA's Jet Propulsion Laboratory in Pasadena, California, for Ranger 7's meeting with the moon. Before Gemini and Apollo, there were Ranger and Surveyor -- robotic ambassadors that did research that paved the way for one small step that was humanity's one giant leap. This vintage NASA film takes you inside mission control and the press room at JPL during Ranger 7's launch and encounter with the moon.

Ranger 7 navigated to and took more than 4,000 close-up images of the moon before its planned impact. This film was produced by JPL for NASA in the 1960s.

Tony De La Rosa

Online plutogno

  • Full Member
  • ****
  • Posts: 725
  • Toulouse, France and Milan, Italy
  • Liked: 113
  • Likes Given: 6
Re: Ranger 7 'Meets' the Moon
« Reply #3 on: 10/11/2014 06:45 PM »
I have found this picture in JPL's Historical Photo of the Month archive for July 2014
http://beacon.jpl.nasa.gov/wp-content/uploads/2014/07/P-2988b_.jpg

The caption says (see http://beacon.jpl.nasa.gov/archives/category/historical-photo-of-the-month ):

Quote
Several different full size and scale models were made of the Ranger spacecraft (Block I, II, and III configurations).  Scale models were used by the projects at a time when there was no computer animation. Engineers and scientists used them to visualize the spacecraft and its orientation as it reached the moon or a planet.

Three members of the Ranger 7 television experiment team stand near a scale model and lunar globe.  From left: Ewen Whitaker, Dr. Gerard Kuiper, and Ray Heacock. Kuiper was the Director of the Lunar and Planetary Laboratory at the University of Arizona, Tuscon. Whitaker was a Research Associate at LPL. Heacock was the Lunar and Planetary Instruments Section Chief at JPL.

I am wondering: why is there a sign in Russian (!) just below the Moon?

Offline Wayne Hale

  • Full Member
  • *
  • Posts: 195
  • Liked: 323
  • Likes Given: 2
Re: Ranger 7 'Meets' the Moon
« Reply #4 on: 10/12/2014 01:30 AM »
When a young person starts a conversation with "My parents let me stay up late at night to watch . . . [historic space event]", I always think of Ranger 7.  That was my 'stay up late at night' story

Offline edkyle99

  • Expert
  • Senior Member
  • *****
  • Posts: 12782
    • Space Launch Report
  • Liked: 3548
  • Likes Given: 610
Re: Ranger 7 'Meets' the Moon
« Reply #5 on: 04/26/2015 04:17 AM »
The RCA television camera system on the Block 3 Rangers was amazing for its time.  There were six cameras.  Each used a Vidicon tube.  The cameras sequentially took exposures and then were scanned to create a steady stream of telemetry during the final hectic minutes of the mission.  More than 4,000 images in about 13 minutes for Ranger 7.  Pretty good resolution too, that still stands up today.  Analog!

http://nssdc.gsfc.nasa.gov/nmc/experimentDisplay.do?id=1964-041A-01

I wonder why such vidicon based camera systems could not be made to work for military satellite reconnaissance during the 1960s.  Resolution, I suppose, along with the telemetry problem.  Attempts were made with SAMOS, but I believe those were film-based systems.  Lunar Orbiter ended up using SAMOS-derived camera systems, but the Ranger camera system seemed to be limited to weather satellite use.

 - Ed Kyle
« Last Edit: 04/26/2015 04:21 AM by edkyle99 »

Online Blackstar

  • Veteran
  • Senior Member
  • *****
  • Posts: 10951
  • Liked: 2436
  • Likes Given: 1
Re: Ranger 7 'Meets' the Moon
« Reply #6 on: 04/26/2015 02:50 PM »
I wonder why such vidicon based camera systems could not be made to work for military satellite reconnaissance during the 1960s.  Resolution, I suppose, along with the telemetry problem.  Attempts were made with SAMOS, but I believe those were film-based systems.  Lunar Orbiter ended up using SAMOS-derived camera systems, but the Ranger camera system seemed to be limited to weather satellite use.

Vidicon was considered for the first reconsats. In fact, I believe that's the system discussed in the Feed Back report. You can find a copy of Feed Back on the web.

It was ruled out apparently during contract selection because the film-scanning technique was considered better. However, I don't know exactly why it was ruled out and why film-scanning was considered better. It had to do with resolution.

Offline jg

  • Full Member
  • **
  • Posts: 242
  • Liked: 89
  • Likes Given: 6
Re: Ranger 7 'Meets' the Moon
« Reply #7 on: 04/26/2015 05:38 PM »
I wonder why such vidicon based camera systems could not be made to work for military satellite reconnaissance during the 1960s.  Resolution, I suppose, along with the telemetry problem.  Attempts were made with SAMOS, but I believe those were film-based systems.  Lunar Orbiter ended up using SAMOS-derived camera systems, but the Ranger camera system seemed to be limited to weather satellite use.

Vidicon was considered for the first reconsats. In fact, I believe that's the system discussed in the Feed Back report. You can find a copy of Feed Back on the web.

It was ruled out apparently during contract selection because the film-scanning technique was considered better. However, I don't know exactly why it was ruled out and why film-scanning was considered better. It had to do with resolution.

Vidicon tubes are TV resolution devices, even those using silicon; they use magnetically controlled electron beams to scan the photosensitive surface; think of them as the inverse of old fashioned TV tubes.  These are what were in commercial TV cameras until eventually dethroned by CCD's much later.

So your best resolution is in order 500x500, or maybe a bit higher (if it was pushed). I certainly don't know how far that could be pushed in the 1960's. These are what were in commercial TV cameras until eventually dethroned by CCD's much later.

Linear photodiode detectors were being developed in the 1970's; by the late 1970's, you could get such detectors that were thousands of pixels long.  So you only had to scan the image in one dimension.  Astronomers tracked that technology as it was useful for spectrographs.  For imaging, astronomers don't have enough photons to throw almost all of them away, so we were tracking CCD development in the 1970s.  My lab at MIT used the first 100x100 resolution CCD's (for experimentation) in the mid 1970's.  By the late 1970's, RCA had a 512x340 resolution CCD intended to replace silicon vidicon tubes and Jim Gun was fabricating the CCD chips for the first Hubble Camera that were at the edge of silicon technology (we couldn't afford to do that, and not enough chips were available then to get any from NASA); those CCD's were in the 1kx1k resolution, range, IIRC, and backlit and thinned.  But management vision failed at RCA, and after a few years, the engineers went elsewhere, along with CCD production.

SAMOS had film with resolution that IIRC was around 500 line pairs resolution (as determined by Dennis Wingo's Lunar Orbiter Image Recovery project).  The camera in Lunar Orbiter used the SAMOS film system, used commercial (COTS) lenses rather than the optics designed for SAMOS by James G. Baker, and scanned the film at lower resolution.  I think there may be enough information on the LOIRP web site to find out what technology was used to scan the film.  I expect behind the scenes, Jim Baker, who was an astronomer as well as the worlds premier optical designers, probably had a lot to do with Lunar Orbiter being able to use the SAMOS camera system for Apollo.  Anyone who has not looked at the images that LOIRP has recovered should: they are competitive with the 3 decades later LRO data.  See: http://en.wikipedia.org/wiki/Lunar_Orbiter_program

Above and beyond whatever other problems SAMOS had, getting the data down was a tremendous problem and was clearly a major limitation to what SAMOS could do; no encryption then; they only downlinked data over the US.  No image compression, other than what cleverness they could squeak out of the analog system on a per pixel basis, which is to say, essentially zip more than being careful in their bandwidth usage. No relay satellites.  Really, really limited (by today's standards) coverage as a result.  I think SAMOS failed by trying to be too far ahead of the times.  Bandwidth of parachuting the film down was much higher than transmitting the data, by many orders of magnitude.  Latency really sucked, though.

In short, vidicon tubes couldn't come close to the resolution needed in the early 1960's, or ever.

Jim

Offline edkyle99

  • Expert
  • Senior Member
  • *****
  • Posts: 12782
    • Space Launch Report
  • Liked: 3548
  • Likes Given: 610
Re: Ranger 7 'Meets' the Moon
« Reply #8 on: 04/26/2015 05:47 PM »
It turns out that NASA also used vidicon camera systems for Mariner and Voyager and Viking and Surveyor, among others.  The later systems had A to D converters and stored the data on tapes for later replay.   Galileo may have been the first NASA deep space probe equipped with CCDs instead of vidicon tubes.  Most of those iconic first-images of planets and moons were made using tube-technology.

Here's a description of one of the Voyager vidicons from
http://pds-rings.seti.org/voyager/iss/inst_cat_wa2.html#filters

"The sensor used in the Voyager Imaging Science Subsystem ISS camera system is a 25mm diameter magnetic deflection vidicon (number B41-003, General Electro-dynamics Co.). The vidicon storage surface (target) is selenium sulphur and can store a high resolution (1500 TV lines) picture for over 100 s at room temperature. The active image area on the target is 11.14 x 11.14 mm. Each frame consists of 800 lines with 800 picture elements (pixels) per line, i.e., 1 pixel = 14 microns. One frame requires 48 s for electronic readout."

Here's a photo of a Viking type vidicon.
http://www.digicamhistory.com/Janesick_Viking_Vidicon.jpg

Note that the Galileo CCD was an 800 x 800 pixel device, similar to the Voyager vidicon.  Casinni has 1024 x 1024 sensors.

 - Ed Kyle
« Last Edit: 04/26/2015 06:16 PM by edkyle99 »

Offline Antilope7724

  • Full Member
  • ****
  • Posts: 411
  • Watched Freedom 7 on live TV
  • California
  • Liked: 276
  • Likes Given: 249
Re: Ranger 7 'Meets' the Moon
« Reply #9 on: 04/27/2015 01:20 AM »
Too bad none of the earlier Block II Rangers worked. It would have been interesting to see if the balsawood hard-landing sphere would have worked to land instruments on the lunar surface.

I remember as a child, watching the Ranger 6 and Ranger 7 missions on TV. We lived in the Los Angeles area and local TV stations carried the mission crash landings live.

It was a real disappointment when Ranger 6 seemed to be working fine all the way to the moon, until they attempted to turn on the TV cameras just before it crashed into the moon.  I believe the TV cameras were accidently turned on during launch and some type of electrical arcing burned them out, it was later determined.

Finally, after six failures, Ranger 7 worked and returned video as it crashed into the moon. That was a real thrill to watch. I was about 11 years old at the time.
« Last Edit: 04/27/2015 01:38 AM by Antilope7724 »

Offline edkyle99

  • Expert
  • Senior Member
  • *****
  • Posts: 12782
    • Space Launch Report
  • Liked: 3548
  • Likes Given: 610
Re: Ranger 7 'Meets' the Moon
« Reply #10 on: 04/27/2015 02:32 AM »
I had forgotten that Ranger 7 took the first photo of the Moon ever taken by a U.S. spacecraft.  So badly did the U.S. falter at lunar exploration during the first seven years of the space age that it wasn't until 13:09 UT on July 31, 1964 that the first U.S. image was captured, by Ranger 7.  According to NASA, the image was taken "about 17 minutes before impacting the lunar surface. The area photographed is centered at 13 S, 10 W and covers about 360 km from top to bottom. The large crater at center right is the 108 km diameter Alphonsus. Above it is Ptolemaeus and below it Arzachel."

Before it was done 17 minutes later, Ranger 7 had provided images of craters and rocks and landscapes never before seen by any camera.

 - Ed Kyle
« Last Edit: 04/27/2015 02:34 AM by edkyle99 »

Offline the_other_Doug

  • Senior Member
  • *****
  • Posts: 2490
  • Minneapolis, MN
  • Liked: 1519
  • Likes Given: 2686
Re: Ranger 7 'Meets' the Moon
« Reply #11 on: 04/27/2015 02:35 AM »
And the little area of the Moon where Ranger 7 crashed was renamed Mare Cognitum -- The Known Sea.

I always thought that was a really kewl touch.
-Doug  (With my shield, not yet upon it)

Offline pargoo

  • Lifelong space fan
  • Full Member
  • ****
  • Posts: 637
  • Australia
    • Buran - wait, the Russians had a Space Shuttle?
  • Liked: 46
  • Likes Given: 0
Re: Ranger 7 'Meets' the Moon
« Reply #12 on: 04/27/2015 07:19 AM »
     A good launch photo.

Offline catdlr

  • Member
  • Senior Member
  • *****
  • Posts: 4656
  • Marina del Rey, California, USA
  • Liked: 1472
  • Likes Given: 900
Re: Ranger 7 'Meets' the Moon
« Reply #13 on: 11/11/2017 03:16 AM »
bump for additional historical video...

Ranger VII Photographs of the Moon 1964 NASA-JPL; First Successful US Lunar Spacecraft

Jeff Quitney
Published on Nov 10, 2017


"Views of the moon taken from the Ranger VII starting at 17 minutes prior to lunar impact. The Ranger series was the first U.S. attempt to obtain close-up images of the Lunar surface. The Ranger spacecraft were designed to fly straight down towards the Moon and send images back until the moment of impact. The project ran from 1961 - 1965. Film #L-840."

Ranger 7 was the first US space probe to successfully transmit close images of the lunar surface back to Earth. It was also the first completely successful flight of the Ranger program. Launched on 28 July 1964, Ranger 7 was designed to achieve a lunar impact trajectory and to transmit high-resolution photographs of the lunar surface during the final minutes of flight up to impact. The spacecraft carried six television vidicon cameras, 2 wide angle (channel F, cameras A and B) and 4 narrow-angle (channel P) to accomplish these objectives. The cameras were arranged in two separate chains, or channels, each self-contained with separate power supplies, timers, and transmitters so as to afford the greatest reliability and probability of obtaining high-quality video pictures. No other experiments were carried on the spacecraft.

Spacecraft design

Rangers 6, 7, 8, and 9 were the so-called Block 3 versions of the Ranger spacecraft. The spacecraft consisted of a hexagonal aluminum frame base 1.5 m across on which was mounted the propulsion and power units, topped by a truncated conical tower which held the TV cameras. Two solar panel wings, each 739 mm wide by 1537 mm long, extended from opposite edges of the base with a full span of 4.6 m, and a pointable high gain dish antenna was hinge mounted at one of the corners of the base away from the solar panels. A cylindrical quasi-omnidirectional antenna was seated on top of the conical tower. The overall height of the spacecraft was 3.6 m.

Propulsion for the mid-course trajectory correction was provided by a 224 N thrust monopropellant hydrazine engine with 4 jet-vane vector control. Orientation and attitude control about 3 axes were enabled by 12 nitrogen gas jets coupled to a system of 3 gyros, 4 primary Sun sensors, 2 secondary Sun sensors, and an Earth sensor. Power was supplied by 9792 Si solar cells contained in the two solar panels, giving a total array area of 2.3 square meters and producing 200 W. Two 1200 watt-hour AgZnO batteries rated at 26.5 V with a capacity for 9 hours of operation provided power to each of the separate communication/TV camera chains. Two 1000 watt.hour AgZnO batteries stored power for spacecraft operations...

Mission profile

The Atlas 250D and Agena B 6009 boosters performed nominally at launch inserting the Agena and Ranger into a 192 km altitude Earth parking orbit. Half an hour after launch the second burn of the Agena engine injected the spacecraft into a lunar intercept trajectory.

Ranger 7 reached the Moon on 31 July... Transmission of 4,308 photographs of excellent quality occurred over the final 17 minutes of flight. The final image was taken before impact has a resolution of 0.5 meters. The spacecraft encountered the lunar surface in direct motion along a hyperbolic trajectory, with an incoming asymptotic direction at an angle of -5.57 degrees from the lunar equator. The orbit plane was inclined 26.84 degrees to the lunar equator. After 68.6 hours of flight, Ranger 7 impacted in an area between Mare Nubium and Oceanus Procellarum (subsequently named Mare Cognitum) at approximately 10.35S 20.58W. (The impact site is listed as 10.63 S, 339.34 E in the initial report "Ranger 7 Photographs of the Moon".) Impact occurred at 13:25:48.82 UT at a velocity of 2.62 km/s. The spacecraft performance was excellent.

Ranger 7 is credited with beginning the "peanut" tradition at NASA command stations. On the success of Ranger 7, someone in the control room was noticed eating peanuts - surely the reason the mission was successful. Since 1964 control rooms ceremonially open a container of peanuts for luck and tradition.

---------------------------------------

Reupload of a previously uploaded film with improved video & sound.

Originally a public domain film from NASA, slightly cropped to remove uneven edges, with the aspect ratio corrected, and one-pass brightness-contrast-color correction & mild video noise reduction applied.
The soundtrack was also processed with volume normalization, noise reduction, clipping reduction, and/or equalization (the resulting sound, though not perfect, is far less noisy than the original).


https://www.youtube.com/watch?v=GpdS7kZ1h1M?t=001

Tony De La Rosa

Offline Proponent

  • Senior Member
  • *****
  • Posts: 5156
  • Liked: 783
  • Likes Given: 542
Re: Ranger 7 'Meets' the Moon
« Reply #14 on: 11/12/2017 02:47 AM »
How elegantly presented -- minimal narration.  No need for a sound track.

I recall reading somewhere that when this was presented to astronauts, Wally Schirra brought the house down by yelling "Bail out, you fool!"

Offline the_other_Doug

  • Senior Member
  • *****
  • Posts: 2490
  • Minneapolis, MN
  • Liked: 1519
  • Likes Given: 2686
Re: Ranger 7 'Meets' the Moon
« Reply #15 on: 11/13/2017 06:45 PM »
How elegantly presented -- minimal narration.  No need for a sound track.

I recall reading somewhere that when this was presented to astronauts, Wally Schirra brought the house down by yelling "Bail out, you fool!"

Interesting -- in the version of the story I have heard, Schirra yelled "Pull up, you fool!  Pull UP!!!"

:)
-Doug  (With my shield, not yet upon it)

Offline eric z

  • Full Member
  • **
  • Posts: 245
  • Liked: 118
  • Likes Given: 316
Re: Ranger 7 'Meets' the Moon
« Reply #16 on: 11/13/2017 07:36 PM »
 Thanks a million to Catldr and everyone else; another "My day is made" moment at Nasaspaceflight.com! It's interesting to think if a program today would make it past six failures...When you compare these glorious views to what was just achieved whizzing by Pluto, it's absolutely amazing how far we've come - But the wonder and awe are still there!

Offline whitelancer64

Re: Ranger 7 'Meets' the Moon
« Reply #17 on: 11/13/2017 08:15 PM »
I have found this picture in JPL's Historical Photo of the Month archive for July 2014
http://beacon.jpl.nasa.gov/wp-content/uploads/2014/07/P-2988b_.jpg

The caption says (see http://beacon.jpl.nasa.gov/archives/category/historical-photo-of-the-month ):

Quote
Several different full size and scale models were made of the Ranger spacecraft (Block I, II, and III configurations).  Scale models were used by the projects at a time when there was no computer animation. Engineers and scientists used them to visualize the spacecraft and its orientation as it reached the moon or a planet.

Three members of the Ranger 7 television experiment team stand near a scale model and lunar globe.  From left: Ewen Whitaker, Dr. Gerard Kuiper, and Ray Heacock. Kuiper was the Director of the Lunar and Planetary Laboratory at the University of Arizona, Tuscon. Whitaker was a Research Associate at LPL. Heacock was the Lunar and Planetary Instruments Section Chief at JPL.

I am wondering: why is there a sign in Russian (!) just below the Moon?

The first word is "boiling" and the rest I have no idea... but the second word seems to start with "мыщ"

Link to story with large image: https://www.jpl.nasa.gov/blog/2014/7/ranger-7-spacecraft-model
"One bit of advice: it is important to view knowledge as sort of a semantic tree -- make sure you understand the fundamental principles, ie the trunk and big branches, before you get into the leaves/details or there is nothing for them to hang on to." - Elon Musk
"There are lies, damned lies, and launch schedules." - Larry J

Offline WallE

  • Full Member
  • *
  • Posts: 162
  • Liked: 27
  • Likes Given: 0
Re: Ranger 7 'Meets' the Moon
« Reply #18 on: 11/15/2017 11:14 PM »
It was a real disappointment when Ranger 6 seemed to be working fine all the way to the moon, until they attempted to turn on the TV cameras just before it crashed into the moon.  I believe the TV cameras were accidently turned on during launch and some type of electrical arcing burned them out, it was later determined.

A normally harmless phenomenon during Atlas launches was for a small amount of propellant to be released into the air at booster jettison, envelope the vehicle, and flash due to contacting the sustainer engine exhaust. On Ranger 6, some of this propellant contacted an electrical disconnect plug on the payload fairing, ignited, and created a short. There was a hinged door covering the plug, but it was very flimsy and came loose during ascent. As a result, the cameras shorted out and became inoperable.

The cause of the failure was correlated by studying film footage of Atlas launches (Ranger 6 was launched on a cloudy day, so they had to look at film of other Atlases) which showed the propellant cloud at BECO and examining telemetry which showed some momentary abnormal behavior from the probe right at the point of staging. On Ranger 7, the door covering the electrical disconnect plug was made to be more sturdy.


Online Citabria

  • Member
  • Full Member
  • *
  • Posts: 144
  • Michigan
  • Liked: 54
  • Likes Given: 30
Re: Ranger 7 'Meets' the Moon
« Reply #19 on: 11/16/2017 04:30 PM »
LRO and Apollo images of Ranger 7 impact site:
http://lroc.sese.asu.edu/posts/52
« Last Edit: 11/16/2017 05:06 PM by Citabria »

Tags: