posted 10-06-2012 05:43 PM               

Prior to the abort of Apollo 13, Apollo 14 was targeted to land in the Littrow region of Mare Serenitatis, where the objective was to study young, pyroclastic volcanic deposits. Following the Apollo 13 abort, it was decided to retarget Apollo 14 to the Fra Mauro site, which was regarded as scientifically more important than the Littrow site. Also, landing in Fra Mauro would allow the astronauts to obtain orbital photography of the Descartes region, something that was not possible if Littrow was the landing site. Descartes was regarded as a high-priority target for a later mission (eventually flown by Apollo 16), but could not be certified as a safe landing site based on Lunar Orbiter photography. Although Littrow was rejected as the Apollo 14 landing site, another site in Mare Serenitatis, Taurus-Littrow, was later explored by Apollo 14.

posted 10-06-2012 05:59 PM               

Later in 1970, Apollos 15 and 19 were cancelled and the landing sites revised. The "old" Apollo 15 (also a H mission) was being considered for Hadley Rille, not the Hadley-Appenine site that the "new" 15 (now a J Mission) eventually landed. Apollo 16 always seemed destined for Descartes.

The real question was where to send 17. The final three candidate sites were: Taurus-Littrow (resurrected by orbital photography from Apollo 15), the Marius Hills complex, and a large crater, probably Copernicus (the scientists wanted Tycho but were told that would never happen).

posted 10-17-2012 10:44 AM               

Here's a 1968 report entitled Lunar Landing Mission Sites Recommended By The Group For Lunar Exploration Planning

The report recommends three possible landing sites in the area of Schroeter's Valley, which was the committee's #8 choice.

posted 10-17-2012 11:47 AM               

Schroter's Valley is too far North and was deemed to be inaccessible to Apollo by the operations people, even for the H missions. It also became moot when Hadley-Appenine was chosen for Apollo 15's landing site. The scientists would get a landing near a rille, but it would be Hadley's.

I do not believe that the TLP issue was even a factor in the decision process.

posted 10-17-2012 01:59 PM               

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Originally posted by Headshot:
Schroter's Valley is too far North and was deemed to be inaccessible to Apollo by the operations people, even for the H missions.

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Apollo 15's Hadley Rille landing site was a full degree farther north than the Shroeter's Valley landing site near Aristarchus. Perhaps Longitude may have been another factor. No other Apollo landing site had a Longitude as far away from the lunar Meridian as the recommended Schroeter's Valley landing site (49.5W).

The location likely made high resolution photographic reconnaissance of the area by Apollo mapping missions leading up to a landing there problematic.

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It also became moot when Hadley-Appenine was chosen for Apollo 15's landing site. The scientists would get a landing near a rille, but it would be Hadley's.

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The Aristarchus site at Schroeter's Valley not only had a rille, but also the "Cobra Head" feature. Would have been interesting to explore the "source" of the rille:

"Schroeter's Valley terminates on one end in what early selenographers were inspired to call the Cobra Head, a large deep depression which is interpreted as its source."

However, as you already mentioned above, the area had accessibility issues, being described as "rather rugged," and the Cobra Head itself, although "a very important feature, would be inaccessible."

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I do not believe that the TLP issue was even a factor in the decision process.

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Perhaps not in the final decision process, but TLP definitely was a significant consideration in the panel's recommendation starting on the summary page where it makes reference to the Cobra Head's "transient phenomena" on p. vi. Also, the main write up on p. 40 states the Cobra Head "is characterized by its high thermal anomaly and the repeated occurrence of transient phenomena."

posted 10-17-2012 02:28 PM               

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Originally posted by Fra Mauro:
What was the appeal of Marius Hills, besides the relative safeness of the site?

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posted 10-17-2012 03:09 PM               

There is a very nice diagram of Apollo landing site accessibility on page 63 of The International Atlas of Lunar Exploration.

posted 10-18-2012 12:34 AM               

• Apollo 12. Nov 1969; Ocean of Storms, Surveyor 3.
  
• Apollo 13. Mar 1970; Fra Mauro.
  
• Apollo 14. Jul 1970; Crater Censorinus.
  
• Apollo 15. Nov 1970; Littrow Rim.
  
• Apollo 16. Mar 1971; Crater Tycho, first rover, Surveyor 7.
  
• Apollo 17. Late 1971; Marius Hills.
  
• Apollo 18. Early 1972; Schroter's Valley.
  
• Apollo 19. Mid or late 1972; Hyginus Rille.
  
• Apollo 20. Late 1972 or early 1973; Crater Copernicus.

Descartes was not mentioned at all in the early site possibilities. When did that one come up for consideration?

posted 10-18-2012 07:35 AM               

The problem is that several groups were generating landing site lists. Bellcom, the Group for Lunar Exploration Planning (GLEP), the ASSB and at least one other. GLEP's 10 July 1969 list had Descartes listed for the J-5 (Apollo 20) mission. Tycho appeared on a number of lists, but finally George Low threw cold water on that site when he said that he would never allow an Apollo mission to be targeted for Tycho.

The only three sites that were constant on all lists that I have seen were: a "Red" Mare, a "Blue" Mare, and Fra Mauro.

Apollo 11 actually had multiple landing sites. If it launched on July 16, they would target Mare Tranquillitatis; if the launch slipped to July 18 - Sinus Medii; if it slipped further to July 20 - Oceanus Procellarum. Once 11 landed at the Mare Tranquillitatis, scientists had their old "blue" mare and 12 would be sent to a young "red (or slightly less blue)" mare as Don Wilhems called them. Had 11 landed in Oceanus Procellarum, 12 would have probably been sent to Mare Tranquillitatis and Conrad and Bean would have snipped pieces off of Surveyor 5.

Except for Fra Mauro, the rest of the landing site choices evolved as we: (1)
learned more about the moon from samples returned by previous missions and (2) got back hi-res photography of other potential landing sites.

The other monkey in the wrench for these landing site lists is that in 1970, three Apollo missions were cancelled and 13 failed to land. So that year we lost four landing sites and the lists had to be pared down accordingly which, of course, made for some intense meetings.

posted 10-18-2012 11:41 AM               

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Originally posted by Glint:
When did the relatively northerly Schroeter's Valley/Cobra Head site fall off the list?

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Still looking for a definitive answer to my own question, found an online NASQ HQ history source with a table showing that as of June, 1969, Shroeter's Valley (i.e. Aristarchus) was still on the list.

Later, there's another table indicating that by the following month the Aristarchus site was not included in a list of 10 sites proposed for Apollos 11-20 by the Apollo Site Selection Board.

posted 10-18-2012 12:29 PM               

Amen to that statement Glint.

I once tried to put together an Excel Spreadsheet of the landing site candidates by mission and time from the various tables in Where No Man Has Gone Before and the info in To A Rocky Moon, but soon determined that a two-dimensional sheet was too restrictive. And this spreadsheet did not even include the newly discovered tables included in The International Altas of Lunar Exploration!

Sadly, some of the people involved in the creation of these lists and those who made the final choices are passing into history. And who know how many preliminary or rough draft landing site tables ended up in some dumpster.

posted 10-18-2012 03:17 PM               

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Originally posted by Headshot:
That is an interesting list. Did the publication indicate who or what committee generated it?

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posted 10-27-2012 10:20 AM               

During the Block III portion of the Ranger Program. Schroter's Valley made the final cut for the Ranger IX's impact site list, part of which is as follows:

Launch Date March 21 - Crater Alphonsus
Launch Date March 22 - Crater Copernicus
Launch Date March 23 - Crater Kepler
Launch Date March 24-25 - Schroter's Valley

Obviously Ranger IX made the March 21st date.

posted 04-28-2014 06:48 PM               

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Originally posted by Glint:
Here's a a 1968 report...

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Note that on page 20 they allocated only five minutes for an astronaut to select a location and then place a heat flow probe! Isn't this the experiment that caused so much time delay on Apollo 15?

posted 03-15-2017 02:53 PM               

For example, Apollo 15 would be a J mission? And we would have had at least Apollo 18?

posted 03-21-2017 07:08 AM               

That one month shift, cascading down the mission line might have caused Apollo 19 to fly in Aug 1972, when one of the most intense solar flares on record occurred.
Considering our understanding of the medical implications of such an exposure and the treatments then available, the crew would have most likely been able to return to earth, where they would have succumbed to the their exposure.

posted 03-22-2017 09:06 AM               

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Originally posted by SaturnV:
...they allocated only five minutes for an astronaut to select a location and then place a heat flow probe! Isn't this the experiment that caused so much time delay on Apollo 15?

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