Further Analysis on the Mystery of the Surveyor III Dust Deposits

https://ntrs.nasa.gov/search.jsp?R=20120008741 2019-07-01T17:00:41+00:00Z

Philip Metzger1, Paul Hintze1, Steven Trigwell2, John Lane3

1 Granular Mechanic and Regolith Operations Lab, NASA, Kennedy Space Center, FL 32899 2 Applied Technology, Siera Lobo-ESC, Kennedy Space Center, FL 32899 3 Granular Mechanics and Regolith Operations, Easi-ESC, Kennedy Space Center, FL 32899 Further Analysis on the Mystery of the Surveyor III Dust Deposits

Philip Metzger1, Paul Hintze1, Steven Trigwell2, John Lane3

• The Apollo 12 lunar module (LM) landing near the Surveyor III spacecraft at the end of 1969 has remained the primary experimental verification of the predicted physics of plume ejecta effects from a rocket engine interacting with the surface of the moon. • This was made possible by the return of the Surveyor III camera housing by the Apollo 12 astronauts, allowing detailed analysis of the composition of dust deposited by the LM plume. • It was soon realized after the initial analysis of the camera housing that the LM plume tended to remove more dust than it had deposited. • In the present study, coupons from the camera housing have been reexamined. • In addition, plume effects recorded in landing videos from each Apollo mission have been studied for possible clues. • Alan Bean examining Surveyor III. Note that the Apollo 12 LM is in the background. LIM Land· -Ig P·oflle r-"li 200 :E I~ -

I I I ~ :I o 100 I 200 300 400 500 Di'stancefrom LM Landing [m]

I I t

200 Distance, ~ .. 300 Surveyor Crater .rom Surveyor [m] LIM Land· -Ig P·oflle r-"li 200 :E I~ -

I I I ~ :I o 100 I 200 300 400 500 Di'stancefrom LM Landing [m]

I I t

200 Distance, ~ .. 300 Surveyor Crater .rom Surveyor [m] LIM Land· -Ig P·oflle r-"li 200 :E I~ -

I I I ~ :I o 100 I 200 300 400 500 Di'stancefrom LM Landing [m]

I I t

200 Distance, ~ .. 300 Surveyor Crater .rom Surveyor [m]

LM Ground Track IN t Sample Locations 2050 /2048 2051~

...... 2049 .... ~ ...... ~..... Camera 2052 Housing ~ 1037 (bottom)

Surveyor 3 Intrepid

Surveyor III Surveyor Scoop Camera Housing

Surveyor Scoop

Returned to Earth TopoTopo Map Map of of o 50 100 Meters ApolloApollo 12 12 Site Site

Co e sampe 12026 HeadCrater 5 m Contour SurveyorCrater Intervals Block era er (

5780 Sharp Crater Bench alo Crater ~ rater __ ", Coresample -...... __...... n.. Coresamples ~ ...... 12027 12025and 12028 Surveyor Housing Sample #2050

( X-Ray Photoelectron Spectroscopy (XPS)

Surveyor III Camera Housing Coupon Line Scan Bolt Hole

- XPS Analysis of bolt shadow

0.7

0.6 %

0.5 Fe2p 0.4 Ca2p

0.3 concnetration

0.2 Atomic

0.1

0 1234567891011 Analysis point from hole Shear stress along the surface for five cases generated by Fluent CFD: h = 5, 10, 20, 25 [ft] and 45 [m].

Shear Stress Using Sutherland's Formula for Dynamic Viscosity 100

<-- CFD Damian End --->

..... co (j) t5 0.1

- C1 (h =20 ft) - C7 (h =10ft) 0.01 - C2 (h = 5ft) - LM Fly-by (h =25 m) - LM Fly-by (h =45 m) 0.001

o 2 4 6 8 10 12 14

Distance from Nozzle [m] Dynamic Pressure along the surface for five cases generated by Fluent CFD: h = 5,, 10, 20, 25 [ft] and 45 [m].

II I I I I I I I I 104 Dynamic Pressure Using Sutherland's Formula for Dynamic Viscosity

3 10

2 10 - C1 (h =20 ft) 1 - C7 (h =10 ft) 10 - C2 (h = 5 ft) - LM Fly-by (h 25 m) ro 10° = Q:.. - LM Fly-by (h =45 m) ~ 1 ~ 10. I/) I/) Q) 2 It 10. .~ 10.3 E ro c 4 >. 10. 0 <--- CFD Damian End ---> 10.5

10.6

10.7

10.8

10.9 0 2 4 6 8 10 12 14

Distance from Nozzle [m] ~~ ...... LM Flyby simulation at h = 45 [m]. Left axis: (blue line) radial distance traveled by particle from ground track position. Right axis: (green and brown lines) region where shear stress is greater than threshold shear stress, resulting in particle lift for zero cohesion force (green line) and for Sagan’s cohesion force (brown line).

3 3 h = 45 m 2 -- Average Max Horizontal Distance Traveled 2 -- Average Max Threshold Lift Shear Stress -- Average Max Threshold Lift Shear Stress (Cohesion Force = 0) 1 1 8 8 7 7 6 Cohesion Force = 0 Sagan Cohesion 6 ...... 5 5 E 4 4 ...... :::t:. \J 3 3 Q) Cl Q) > I ('0 2 2 q .....

I- ,...... ,* Q) "'0 () R = 109 m po c "-oJ ('0 0.1 0.1 +-' (/) 8 8 (5 7 7 6 6 5 5 4 4

3 3

2 2

0.01 0.01

2 10 o [~lln] Interparticle Force (cohesion force or pull-off force)

sp = 2πγDF

.A-"" --r-- γ = 0.075 [J/m2] Walton, O.R., “Review of Adhesion Fundamentals for

.J.--T Micron-Scale Particles”, Powder and Particle Journal, 26, --+-1 2008, pp. 129-141. [N] p I

3−n p = DKI

K = 6×10-7 [N/m1/2] c- 1x 10-6 1x 10-5 5 x 10-5 1x 10-4 n = 5/2 Iversen, J.D, B.R. White, “Saltation Threshold on Earth, D [m] Mars, and Venus”, Sedimentology, 29, 1982, pp. 111-119.

Radial distance traveled by particle from ground track position as a function of particle diameter for h = 45 m. Circles represent different starting points, both x and y. Solid line is the average maximum value of the individual trajectories.

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3 4 5 6 7 8 9 2 3 4 5 6 7 8 9 1 10 o [um] Apollo 12 After Touchdown

t = 0 s Apollo 12 After Touchdown

t = 4 s Apollo 12 After Touchdown

t = 6 s Apollo 12 After Touchdown

t = 12 s Apollo 12 After Touchdown

t = 16 s Apollo 12 After Touchdown

t = 20 s Apollo 12 After Touchdown

t = 24 s Apollo 12 After Touchdown

t = 28 s Apollo 12 After Touchdown

t = 32 s Apollo 12 After Touchdown

t = 36 s Freefall and Darcy law particle trajectories compared to luminosity

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r"'"""""'1 \ S , L...... I ~ 1.0

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l: e r ag Mean: Level: Mean: 40.27 Level: Std Dev: Count: 1.12 Count: Percentile: 40 Percentile: 50S

Channel: Luminosity -----vn

5 J r: E I I I 9 Mean: 44.44 Level: Mean: 40.52 Level: Std Dev: 1.57 Count: 1.23 Count: Median: 44 Percentile: 41 Percentile: Pixels: 357 Cache Level: 494 Cache Level:

• Apollo 15: Descent

luminosity sample area Apollo 15: Descent

luminosity sample area Apollo 15: Ascent

luminosity sample area Apollo 15: Descent

luminosity sample area 250 Apollo 15: Absolute Luminosity Value (0-255)

200

-- Descent Luminosity --- Ascent Luminosity

>- 150 / \ ... / Ow II o II\ c II/ I E III I :J -I ; I I •J I 100 J I :I J ·I \ ·I \ -:.

50 Notes: 1. Data is luminosity at 1 s intervals to the end of the video. 2. Descent is the luminosity of a dark crater in the background, starting with touchdown. 3. Ascent is the luminosity of the sky between the left two stars, starting as the LM is lifting off.

O--

Elapsed Time of Video [s] I I I I 2 Apollo 15: Normalized Luminosity Value (0-1) ..-... c 1 E -I / 7 \ " 1 Descent Luminosity x 6 \ 1 co 5 --- Ascent Luminosity E -I 4 ..-... ----c 3 E 2 ,. \ -I \ ..-... \ +oJ \ --I \ 0.1 \ -II \

+oJ>- 7 \ ·w 6 \ 0 C 5 \ E 4 "- :::::l \ -I 3 \ "'0 '- - .... (1) \ .~ 2 \ co \ 1\ E.... "- I \ , 0 \ .... Z 0.01 I I " / "- / 7 \ J 6 \ J 5 \ I -5 0 5 10 15 20 25 30

Elpased Time from Start of Event [s] Further Analysis on the Mystery of the Surveyor III Dust Deposits Summary

• Several likely scenarios are proposed to explain the Surveyor III dust observations. • These include electrostatic levitation of the dust from the surface of the Moon as a result of periodic passing of the day-night terminator; dust blown by the Apollo 12 LM flyby while on its descent trajectory; dust ejected from the lunar surface due to gas forced into the soil by the Surveyor III rocket nozzle, based on Darcy’s law; and mechanical movement of dust during the Surveyor landing. • Even though an absolute answer may not be possible based on available data and theory, various computational models are employed to estimate the feasibility of each of these proposed mechanisms. • Scenarios can then be tested which combine multiple mechanisms to produce results consistent with observations. •