Friday, August 31, 2012

One of us...

Neil Armstrong Memorial: A photograph of Neil Armstrong displayed on a table during a memorial service celebrating his life, Friday, Aug. 31, 2012, at the Camargo Club in Cincinnati. Armstrong, the first man to walk on the moon, died Saturday, Aug. 25. He was 82 [NASA/Bill Ingalls].
Statio Tranquillitatis - The artifacts of Apollo 11 and man's first footprints, including the stroll by Neil Armstrong to the rim of the crater where he successfully avoided landing, July 20, 1969. LROC Narrow Angle Camera (NAC) observation opportunity M175124932R, LRO orbit 10942, November 5, 2011; full resolution scaled to 40 cm per pixel, angle of incidence 40.98° from an altitude of 24.03 kilometers [NASA/GSFC/Arizona State University].

"From the Earth to the Moon"

Still capture from "From the Earth to the Moon," produced by David Kring, CLSE, NLSI, LPSI.
I have often argued that the Moon is the best and most accessible place in the solar system for robotic and human assets to address fundamentally important scientific questions while simultaneously providing an opportunity to expand our technological capabilities. 

To remind ourselves of the opportunities on the Moon, the Center for Lunar Science and Exploration team has created a brief (3 minute) video with scenes so dramatic you may find yourself reaching out to pick up a rock and becoming restless for a chance to walk among lunar peaks.

The video and soundtrack "From the Earth to the Moon"

*       Provides an inspirational view of the lunar surface, which humans have not visited since 1972, despite being the best and most accessible place in the solar system to explore the fundamental principles of our origins;
*       Highlights vast portions of the lunar surface that have yet to be explored; and
*       Demonstrates how new images are revealing dramatic details of future landing sites suitable for both robotic and human missions.

I encourage you to download the HD version of the video (from the bottom of that website - cross-linked at the bottom of this post) to fully marvel at this tour of the lunar surface.  I also note that we have intentionally produced a few scenes with a patchwork of images of different resolutions to illustrate the additional detail that LRO has provided.

David A. Kring, Ph.D.
Center for Lunar Science & Exploration

Options for download

Downloads can be streamed by clicking on the options below.  For best viewing, however, you may want to right click, save the link to your own computer, and then play the file from your computer
Quicktime (HD 1080p)
Windows Media
(HD 720p)
iPhone 3gs/iPod video

iPhone 4/iPad

Characterisation of Potential Landing Sites for the European Space Agency's Lunar Lander Project

Figure 5.Map of the South Polar Region based on a LOLA DEM, with the locations of the Regions of Interest analyzed in this study. Isolines (circles) are every degree of latitude.
This article describes the characterization activities of the landing sites currently envisaged for the Lunar Lander mission of the European Space Agency.

arXiv:1208.5587v1 [astro-ph.EP]

These sites have been identified in the South Pole Region (-85{\deg} to -90{\deg} latitude) based on favorable illumination conditions, which make it possible to have a long-duration mission with conventional power and thermal control subsystems, capable of enduring relatively short periods of darkness (in the order of tens of hours), instead of utilizing Radioisotope Heating Units. The illumination conditions are simulated at the potential landing sites based on topographic data from the Lunar Orbiter Laser Altimeter (LOLA), using three independent tools.

ESA Lunar Lander project still on-track for 2018 (July 2012)
Risk assessment of the identified sites is also being performed through independent studies. Long baseline slopes are assessed based on LOLA, while craters and boulders are detected both visually and using computer tools in Lunar Reconnaissance Orbiter Camera (LROC) images, down to a size of less than 2 m, and size-frequency distributions are generated. Shadow hazards are also assessed via LROC images. 

The preliminary results show that areas with quasi-continuous illumination of several months exist, but their size is small (few hundred metres); the duration of the illumination period drops quickly to less than one month outside the areas, and some areas present gaps with short illumination periods. Concerning hazard distributions, 50 m slopes are found to be shallow (few degrees) based on LOLA, whereas at the scale of the lander footprint (~5 m) they are mostly dominated by craters, expected to be mature (from geological context) and shallow (~11{\deg}). 

The preliminary conclusion is that the environment at the prospective landing sites is within the capabilities of the Lander design. 

Figure 10. LQCIP map for the six best RoI’s, with RoI name and geodetic coordinates (in the Mean Earth/Polar Axis reference system). Colour-code is in days, height above the surface is 2 m, filter for short darkness periods is 60 hours, filter for short illumination periods is 10 hours, and year is 2019. The spacing is 40 m. X, Y coordinates are in polar stereographic projection.

Tuesday, August 28, 2012

A Sawtooth-like Timeline for the First Billion Years of Lunar Bombardment

A revised timeline of lunar bombardment, featuring greater granularity and matching new assumptions. (Figure 3, Morbidelli, Marchi, Bottke & Kring, 2012) [ arXiv:1208.4624v1 ].
Morbidelli, Marchi, Bottke & Kring
OCA, Nice
Center for Lunar Origin & Evolution, SwRI, Boulder
Center for Lunar Science & Exploration, USRA -
Lunar and Planetary Institute, Houston

We revisit the early evolution of the Moon's bombardment.

Our work combines modeling (based on plausible projectile sources and their dynamical decay rates) with constraints from the lunar crater record, radiometric ages of the youngest lunar basins and the abundance of highly siderophile elements in the lunar crust and mantle. 

The new profile for lunar bombardment
matches a population of 150 basins since
lunar formation
[Frey (2009)].
We deduce that the evolution of the impact flux did not decline exponentially over the first billion years of lunar history, and no prominent and narrow impact spike 3.9 billion years ago, unlike that typically envisioned in the lunar cataclysm scenario. Instead, we show the timeline of the lunar bombardment has a sawtooth-like profile with an uptick in the impact  flux near 4.1 billion years ago. The impact flux at the beginning of this weaker cataclysm was 5-10 times higher than during the immediately preceding period.

The Nectaris basin should have been one of the first basins formed at the sawtooth. We predict the bombardment rate since 4.1 billion years ago declined slowly and adhered relatively close to classic crater chronology models (
Neukum and Ivanov (1994)). Overall we expect the sawtooth event accounted for about 1/4 the total bombardment suffered by the Moon since its formation. Consequently, considering that 12-14 basins formed during the sawtooth event, we expect the net number of basins formed on the Moon was 45-50.

From our expected bombardment timeline, we derived a new and improved lunar chronology suitable for use on Pre-Nectarian surface units. According to this chronology, a significant portion of the oldest lunar cratered terrains have an age of 4.38 - 4.42 billion years. Moreover, the largest lunar basin, South Pole-Aitken, is older than 4.3 billion years and was therefore not produced during the lunar cataclysm.

Passing of an Era

Neil Armstrong examines a sample from the Sierra Madera impact crater, west Texas during geology training for the Apollo program.

Paul Spudis
The Once & Future Moon
Smithsonian Air & Space

Because of his flying career and the life that he led, Neil Armstrong’s passing has many recounting his place in the history of spaceflight and remembering a life well lived.  He holds a special place in our hearts and a unique place in history – and he always will.

I met Neil Armstrong at a conference, an encounter I won’t forget.  A quiet, unassuming man of medium height and build, pleasant and genial, surrounded by a horde of admirers and well-wishers, I could tell he was slightly uncomfortable with (but resigned to) the adulation he received.  In his mind, the 1969 flight of Apollo 11 was simply another professional assignment he flew as a test pilot – the landing on the Moon was of more significance than his first step on it.  He was an aviator, in every sense of that word.  The landing was an accomplishment for humanity – a giant step for mankind.

My glimpses of Neil come not from personal encounters with him, but from others who knew him.  During a discussion several years ago with Dave Scott (Apollo astronaut and Commander of the 1971 Apollo 15 mission), I inquired about an obscure incident during the 1966 flight of Gemini 8 (flown by Neil and Dave).  That mission conducted the first docking of two spacecraft in space and I wanted to know some details of the emergency experienced by the crew on that flight.

The incident had occurred shortly after the docking, when the Gemini-Agena spacecraft began to roll slightly.  The rate of rotation became greater with time and it was evident that something was very wrong.  Neil, as commander, was responsible for “flying” the spacecraft but couldn’t get the rolling under control.  Thinking that the Agena (their unmanned target vehicle) was responsible, the crew made the decision to undock from it (they were out of contact with Mission Control at the time).  As soon as they did, the Gemini spacecraft started to roll and tumble at an ever increasing and alarming rate.  Dave recalled with a chuckle that Neil looked over at him, pointed at the attitude control stick and said “See if you can do anything with it!”  Dave’s recollection of their exchange gave me a glimpse of a very human moment in a life and death situation.  This was serious – if they couldn’t regain control, they would black out from the centrifugal forces in the tumbling vehicle.  Neil kept his cool, activated the re-entry thrusters and soon stabilized the bucking Gemini spacecraft.  The solution saved their lives but ended the mission, sending them home prematurely but safely.

The story of the first lunar landing is well known.  The automatic systems of the Apollo 11 Lunar Module Eagle were targeting the vehicle into a large crater filled with automobile-sized boulders.  Landing there would be disastrous, as the LM would likely topple over on touchdown, eliminating the crew’s ability to liftoff from the Moon and return home.  Taking manual control, Neil (with Mission Control advising the crew they had thirty seconds of fuel left) guided the LM over the hazardous debris field to a safe touchdown a few hundred meters beyond the original landing site.  Tension during the agonizingly long pause in the air-to-ground communications was palpable.  Relief could be heard in Capcom Charlie Duke’s voice as Neil calmly announced that the Eagle had landed.  Yet again, a critical situation expertly handled by a test pilot just doing his job – the calm and collected decision making necessary when flying finicky machines near the edges of their performance envelopes.

Neil’s scientific work on the Moon during his EVA warrants special mention.  Being the first humans to  land on another world, it is understandable that the crew had many ceremonial duties to perform.  Although they had been carefully instructed to stay close to the LM, without informing Mission Control, Neil walked back a hundred meters or so to Little West crater (overflown earlier) to examine and photograph its interior.  Those photos showed the basaltic bedrock of Tranquility Base – documenting that the Eagle had landed amidst ejecta from that crater thereby establishing the provenance of samples collected during the crew’s limited time on the surface.  According to Gene Shoemaker and Gordon Swann, both of the U.S. Geological Survey, Neil was one of the best students of geology among the Apollo astronauts.  Through his work on the Moon, he showed an ability beyond mere mastery of the facts of geology – he intuitively grasped its objectives, as well as the philosophy of the science.  Like every other facet of the mission, Neil understood and took this role seriously.  No matter what topic was addressed or which role was taken, he could always be counted on to turn in his best performance.

Armstrong understood the historic role of being the first man on the Moon but he never succumbed to the siren call of fame.  He could have cashed in on his status but choose a different path.  He was the quintessence of quiet dignity, possessing the “Aw shucks, t’weren’t nothin’” Gary Cooper-ish manner of understated heroism.  After retirement, he lived happily in his home state of Ohio, taught aeronautics (his first love) at the University of Cincinnati, and advised on various engineering topics and problems for both government and industry.  Throughout NASA’s post-Apollo efforts – without fanfare – he often and freely lent his efforts to the space program.  He served his country with honor and dignity.

As a test pilot, Neil routinely showed his ability to make quick, life saving decisions in dangerous situations.  As a senior spokesman for space, he clearly voiced his concern over the dismantling and destruction of our national space program.  Neil understood that our civil space program is a critical national asset, both as a technology innovator and a source of inspiration for the public.  Who would recognize this more clearly than Neil Armstrong?  From long experience, he knew what kinds of government programs worked and what kind didn’t.  He knew his fellow man.  In appearances before Congress in recent years, he outlined specific objections to our current direction in space.  A true patriot, Neil did not hesitate to voice his opinions, whether they aligned with current policy or not.

It’s become cliché to say that Neil Armstrong holds a unique place in history.  On this occasion, we should pause to consider just how singular his place is.  No one – not the first human to Mars nor the first crew to venture beyond the Solar System – will ever achieve the same level of significance as the first human to step onto the surface of another world.  The flight of Apollo 11 was truly a once in a lifetime event – and by that, I mean in the lifetime of humanity.  That first step was indeed one to “divide history,” as the NASA Public Affairs Office put it at the time.

Goodbye, Neil Armstrong – and thank you.  We’ve lost one of our most authoritative and articulate spokesmen for human spaceflight.  I mourn him and share his valid concerns for our dysfunctional national space program.

Originally published at his Smithsonian Air & Space blog The Once and Future Moon, Dr. Spudis is a senior staff scientist at the Lunar and Planetary Institute. The opinions expressed are those of the author and are better informed than average.

"Houston, Tranquility base here."

Apollo 11 landing site, as Armstrong and Aldrin left it some 43 years ago, LROC Narrow Angle Camera (NAC) observation M175124932R , LRO orbit 10942, November 5, 2011; angle of incidence 40.98° at 40 cm per pixel resolution from an altitude of 24 kilometers [NASA/GSFC/Arizona State University].
Mark S. Robinson
Principal Investigator
Lunar Reconnaissance Orbiter Camera
Arizona State University

"Houston, Tranquility base here. The Eagle has landed."

With those words Neil Armstrong let the world know that the Apollo 11 lunar module Eagle had set down safely on the surface of the Moon (20 July 1969). They did it! A nearly impossible task, yet there they were, starkly alone, but in a real sense in front of millions of people back on Earth. Only ten other humans would follow Neil Armstrong and Buzz Aldrin to the lunar surface over the next three years. We have not been back since.

First picture from the surface! First picture taken by a human being on another world. View out the lunar module left window, taken by Armstrong shortly after landing. One of the LM thrusters protrudes into the image at the bottom, scattered light from the Sun appears in the upper left, AS11-37-5449 [NASA].
As we remember Neil Armstrong's many accomplishments after his sudden death this week, it is reassuring  to know that the descent stage of Eagle, and various scientific instruments remain untouched, as though the crew only left yesterday. These artifacts are a reminder that humans can accomplish nearly impossible deeds through cooperation and teamwork.

Armstrong collects contingency sample - Armstrong collecting a contingency sample with a specially prepared scoop on a stick. Frame grab from Johnson Space Center digital scan of 16-mm film [NASA].
Once on the surface, Armstrong and Aldrin set about securing the LM and attending to various chores. After six hours it was finally time for Armstrong to head down the ladder. They only had a brief two and a half hours on the surface to accomplish many tasks. One of the first was obtaining a contingency sample (in case they had to leave in an unexpected hurry). Armstrong adeptly collected the sample with a scoop on a stick. After several scoops, he then carefully poured the soil and small rocks into a bag that he stashed in a hip pocket. Armstrong accomplished these precise operations with almost no time to acclimatize to 1/6th gravity! This and other samples collected by Armstrong and Aldrin would become the most studied geologic samples in history.

Armstrong stowing sample - Armstrong stowing contingency sample. Frame grab from Johnson Space Center digital scan of 16-mm film [NASA].
Shortly after completing the contingency sampling, Armstrong noted the magnificent scene before him: "It has a stark beauty all its own. It's like much of the high desert of the United States. It's different, but it's very pretty out here." Buzz joined Neil on the surface and shortly they raised the United States flag and then unpacked, and setup sophisticated science experiments (Early Apollo Scientifc Experiments Package, EASEP) and collected a comprehensive set of samples (one of the greatest science bonanzas ever!). You can easily find the EASEP hardware in the LROC images, just south of the LM descent stage.

American flag goes up! Armstrong and Aldrin deploying the American flag. Frame grab from Johnson Space Center digital scan of 16-mm film [NASA].
As we remember all that Neil Armstrong accomplished during his storied career, LRO and LROC continue Armstrong's journey, collecting critical measurements that will enable America's return to the Moon.

Listen to noted author Andrew Chaikin recall his conversations with Neil Armstrong.

Jump to the NAC frame showing Tranquility base. Scroll through all the LROC images of this historic site.

Previous Apollo 11 LROC Featured Images:

LROC's First Look at the Apollo Landing Sites
Apollo 11: Second Look
High Noon at Tranquility Base
A Stark Beauty All Its Own

Armstrong crater

Armstrong crater, Sea of Tranquility - LROC Narrow Angle Camera mosaic of Armstrong, the appropriately unassuming 4.2 km-wide crater (before 1970, "Sabine E") 47.1 km northwest of Tranquility Base (or roughly 64 km north by northwest of the much easier to locate landmark crater Moltke) at 1.356°N, 24.941°E.  From a highly reduced combination of sampled lines from LROC NAC M126765005 (LRO orbit 3815, 47 cm resolution from 39.5 km altitude, April 24, 2010) and M172758358 (orbit 10593, 49 cm resolution from 42.6 km altitude, ), both under mid-day full illumination but many lunar days apart [NASA/GSFC/Arizona State University].
The image above does not do justice to the 16000 line by 10000 pixel montage needed to catch all of modest Armstrong crater at the highest resolution possible. Only two people ever had the opportunity to catch such a view, and they were very busy at that brief moment, absorbed with the raw novelty and challenge of arriving at the lunar surface

The information is stored in two standard double 5000 sample by 52224 line LRO NAC photographs now available in the Planetary Data System (PDS).

A new barely-born effort is underway to make the several life-times worth of PDS data more user-friendly. You can call this an experiment, an early part of that effort, and like most experiments it is a failure.

To illustrate that failure better, as an additional tease, below, at full resolution, and at the maximum 580 by 800 window allowable to users of this blog format, is a very small part of that wall-sized product, specifically the part of the Armstrong crater wall at roughly 5 o'clock (or 170° of arc) in the 'thumbnail' above featuring a unusually wide line of darker fine debris flow.

Sound principles of super-positioning seem to indicate Armstrong is an old crater on the main-sequence of lunar crater types, barely large enough to have once supported a floor, now long buried by steady mass wasting. It's a pounded, rounded and well-gardened interior and has none of the great boulders on the rim that would set it apart as relatively young. Still, the interplay of epochs that have etched their passing on the Tranquillitatis basin (if it is a true impact basin) is at least as delightful as clouds in a spring day sky. LROC NAC M126765005L [NASA/GSFC/Arizona State University].

Without the jagged features characteristic of younger similarly-sized craters, craters like South Ray, not yet baked evenly into reddened optical maturity, even the highest resolution segment of the mosaic doesn't invite anyone to go through a similar time-consuming process of creating a wall-sized picture of Armstrong crater. Flight planners did not choose this place on the Moon for its drama.

Site B was selected for the first landing so that first pilot would not have to take control from an over-loaded on-board computer to dodge boulders looming up from the spot where the delicate Lunar Module was trying to land.

The dark-line and notch at "5 o'clock" on the rim of Armstrong (inset at original resolution) is more than a superficial darker debris flow, after all. The relief at angles of illumination unavailable at high-resolution definitely show a notch in the crater rim anatomy, at 60 meters resolution. There is also a stream of secondary cratering that amounts to a ray, perhaps from Theophilus. The white arrow is the landing site of Apollo 11. LROC Wide Angle Camera mosaic (604nm) from several orbital passes July 2011 [NASA/GSFC/Arizona State University].
Fortunately, the relatively small crater is not terribly difficult to spot using a modest telescope, if, in addition, an Earth-bound observer has more than a passing knowledge of the Moon's nearside in general and the Sea of Tranquility in particular.

Bit by slow bit we are gathering information that adds up to a fairly accurate simulation of the Moon, but to experience a truly accurate picture of our own back yard we are also having confirmed what we already knew.
You really have to have been there.

From a 33 percent reduction of a truly spectacular color mosaic of the Moon captured by the "miracle boys of Minsk," Astronominsk, April 6, 2009.

Saturday, August 25, 2012

Neil Armstrong 1930 - 2012

Neil Armstrong, first man on the Moon, immediately after the end of his historic EVA, July 21, 1969 [Aldrin/NASA].
CINCINNATI (AP) — Neil Armstrong was a quiet self-described nerdy engineer who became a global hero when as a steely-nerved pilot he made "one giant leap for mankind" with a small step on to the moon. The modest man who had people on Earth entranced and awed from almost a quarter million miles away has died. He was 82.

Armstrong died following complications resulting from cardiovascular procedures, a statement Saturday from his family said. It didn't say where he died.

Armstrong commanded the Apollo 11 spacecraft that landed on the moon July 20, 1969, capping the most daring of the 20th century's scientific expeditions. His first words after setting foot on the surface are etched in history books and the memories of those who heard them in a live broadcast.

"That's one small step for (a) man, one giant leap for mankind," Armstrong said.

In those first few moments on the moon, during the climax of heated space race with the then-Soviet Union, Armstrong stopped in what he called "a tender moment" and left a patch commemorate NASA astronauts and Soviet cosmonauts who had died in action.

Dr. Armstrong in rare interview on Australian television last May.
"It was special and memorable but it was only instantaneous because there was work to do," Armstrong told an Australian television interviewer in 2012.

Armstrong and Edwin "Buzz" Aldrin spent nearly three hours walking on the lunar surface, collecting samples, conducting experiments and taking photographs.

"The sights were simply magnificent, beyond any visual experience that I had ever been exposed to," Armstrong once said.

The moonwalk marked America's victory in the Cold War space race that began Oct. 4, 1957, with the launch of the Soviet Union's Sputnik 1, a 184-pound satellite that sent shock waves around the world.

Although he had been a Navy fighter pilot, a test pilot for NASA's forerunner and an astronaut, Armstrong never allowed himself to be caught up in the celebrity and glamor of the space program.

"I am, and ever will be, a white socks, pocket protector, nerdy engineer," he said in February 2000 in one of his rare public appearances. "And I take a substantial amount of pride in the accomplishments of my profession."

A man who kept away from cameras, Armstrong went public in 2010 with his concerns about President Barack Obama's space policy that shifted attention away from a return to the moon and emphasized private companies developing spaceships. He testified before Congress and in an email to The Associated Press, Armstrong said he had "substantial reservations," and along with more than two dozen Apollo-era veterans, he signed a letter calling the plan a "misguided proposal that forces NASA out of human space operations for the foreseeable future."

Armstrong's modesty and self-effacing manner never faded.

When he appeared in Dayton in 2003 to help celebrate the 100th anniversary of powered flight, he bounded onto a stage before 10,000 people packed into a baseball stadium. But he spoke for only a few seconds, did not mention the moon, and quickly ducked out of the spotlight.

He later joined former astronaut and Sen. John Glenn to lay wreaths on the graves of Wilbur and Orville Wright. Glenn introduced Armstrong and noted it was 34 years to the day that Armstrong had walked on the moon.

"Thank you, John. Thirty-four years?" Armstrong quipped, as if he hadn't given it a thought.

At another joint appearance, the two embraced and Glenn commented: "To this day, he's the one person on Earth, I'm truly, truly envious of."

Armstrong's moonwalk capped a series of accomplishments that included piloting the X-15 rocket plane and making the first space docking during the Gemini 8 mission, which included a successful emergency splashdown.

In the years afterward, Armstrong retreated to the quiet of the classroom and his southwest Ohio farm. Aldrin said in his book "Men from Earth" that Armstrong was one of the quietest, most private men he had ever met.

In the Australian interview, Armstrong acknowledged that "now and then I miss the excitement about being in the cockpit of an airplane and doing new things."

At the time of the flight's 40th anniversary, Armstrong again was low-key, telling a gathering that the space race was "the ultimate peaceful competition: USA versus U.S.S.R. It did allow both sides to take the high road with the objectives of science and learning and exploration."

Glenn, who went through jungle training in Panama with Armstrong as part of the astronaut program, described him as "exceptionally brilliant" with technical matters but "rather retiring, doesn't like to be thrust into the limelight much."

Dr. Armstrong's skill under extreme pressure, on Gemini and and as an accomplished pilot of the sub-orbital X-15 made him a natural choice for the first lunar landing when mission planning came fast in 1968.
Derek Elliott, curator of the Smithsonian Institution's U.S. Air and Space Museum from 1982 to 1992, said the moonwalk probably marked the high point of space exploration.

The manned lunar landing was a boon to the prestige of the United States, which had been locked in a space race with the former Soviet Union, and re-established U.S. pre-eminence in science and technology, Elliott said.

"The fact that we were able to see it and be a part of it means that we are in our own way witnesses to history," he said.

The 1969 landing met an audacious deadline that President Kennedy had set in May 1961, shortly after Alan Shepard became the first American in space with a 15-minute suborbital flight. (Soviet cosmonaut Yuri A. Gagarin had orbited the Earth and beaten the U.S. into space the previous month.)

"I believe this nation should commit itself to achieving the goal, before the decade is out, of landing a man on the moon and returning him safely to Earth," Kennedy had said. "No single space project in this period will be more impressive to mankind, or more important to the long-range exploration of space; and none will be so difficult or expensive to accomplish."

The end-of-decade goal was met with more than five months to spare. "Houston: Tranquility Base here," Armstrong radioed after the spacecraft settled onto the moon. "The Eagle has landed."

The on-board auto sequential still camera captured
Armstrong's first tentative, tethered steps on the Moon.
"Roger, Tranquility," future Apollo 16 lunar module pilot Charlie Duke radioed back, "we copy you on the ground. You've got a bunch of guys about to turn blue. We're breathing again. Thanks a lot."

The third astronaut on the mission, Michael Collins, circled the moon in the mother ship Columbia 60 miles overhead while Armstrong and Aldrin went to the moon's surface.

In all, 12 American astronauts walked on the moon between 1969 and the last moon mission in 1972.

For Americans, reaching the moon provided uplift and respite from the Vietnam War, from strife in the Middle East, from the startling news just a few days earlier that a young woman had drowned in a car driven off a wooden bridge on Chappaquiddick Island by Sen. Edward Kennedy. The landing occurred as organizers were gearing up for Woodstock, the legendary three-day rock festival on a farm in the Catskills of New York.

Armstrong was born Aug. 5, 1930, on a farm near Wapakoneta in western Ohio. He took his first airplane ride at age 6 and developed a fascination with aviation that prompted him to build model airplanes and conduct experiments in a homemade wind tunnel.

As a boy, he worked at a pharmacy and took flying lessons. He was licensed to fly at 16, before he got his driver's license.

Armstrong enrolled in Purdue University to study aeronautical engineering but was called to duty with the U.S. Navy in 1949 and flew 78 combat missions in Korea.

After the war, Armstrong finished his degree from Purdue and later earned a master's degree in aerospace engineering from the University of Southern California. He became a test pilot with what evolved into the National Aeronautics and Space Administration, flying more than 200 kinds of aircraft from gliders to jets.

Armstrong was accepted into NASA's second astronaut class in 1962 — the first, including Glenn, was chosen in 1959 — and commanded the Gemini 8 mission in 1966. After the first space docking, he brought the capsule back in an emergency landing in the Pacific Ocean when a wildly firing thruster kicked it out of orbit.

Armstrong was backup commander for the historic Apollo 8 mission at Christmastime in 1968. In that flight, Commander Frank Borman, and Jim Lovell and Bill Anders circled the moon 10 times, and paving the way for the lunar landing seven months later.

Aldrin said he and Armstrong were not prone to free exchanges of sentiment.

"But there was that moment on the moon, a brief moment, in which we sort of looked at each other and slapped each other on the shoulder ... and said, 'We made it. Good show,' or something like that," Aldrin said.

An estimated 600 million people — a fifth of the world's population — watched and listened to the landing, the largest audience for any single event in history.

Parents huddled with their children in front of the family television, mesmerized by what they were witnessing. Farmers abandoned their nightly milking duties, and motorists pulled off the highway and checked into motels just to see the moonwalk.

Television-less campers in California ran to their cars to catch the word on the radio. Boy Scouts at a camp in Michigan watched on a generator-powered television supplied by a parent.

Afterward, people walked out of their homes and gazed at the moon, in awe of what they had just seen. Others peeked through telescopes in hopes of spotting the astronauts.

In Wapakoneta, media and souvenir frenzy was swirling around the home of Armstrong's parents.

"You couldn't see the house for the news media," recalled John Zwez, former manager of the Neil Armstrong Air and Space Museum. "People were pulling grass out of their front yard."

Armstrong, Aldrin and Collins were given ticker tape parades in New York, Chicago and Los Angeles and later made a 22-nation world tour. A homecoming in Wapakoneta drew 50,000 people to the city of 9,000.

In 1970, Armstrong was appointed deputy associate administrator for aeronautics at NASA but left the following year to teach aerospace engineering at the University of Cincinnati.

He remained there until 1979 and during that time bought a 310-acre farm near Lebanon, where he raised cattle and corn. He stayed out of public view, accepting few requests for interviews or speeches.

"He didn't give interviews, but he wasn't a strange person or hard to talk to," said Ron Huston, a colleague at the University of Cincinnati. "He just didn't like being a novelty."

Those who knew him said he enjoyed golfing with friends, was active in the local YMCA and frequently ate lunch at the same restaurant in Lebanon.

In February 2000, when he agreed to announce the top 20 engineering achievements of the 20th century as voted by the National Academy of Engineering, Armstrong said there was one disappointment relating to his moonwalk.

"I can honestly say — and it's a big surprise to me — that I have never had a dream about being on the moon," he said.

From 1982 to 1992, Armstrong was chairman of Charlottesville, Va.-based Computing Technologies for Aviation Inc., a company that supplies computer information management systems for business aircraft.

He then became chairman of AIL Systems Inc., an electronic systems company in Deer Park, N.Y.

Armstrong married Carol Knight in 1999, and the couple lived in Indian Hill, a Cincinnati suburb. He had two adult sons from a previous marriage.

Dr. Armstrong joined other Apollo veterans in testimony before Congress last August.

Friday, August 24, 2012

Night sky timelapse in Portugal

Heads Up to the wordless tech team :  A beautiful time lapse compilation by astrophotographer Miguel Claro, in Portugal. He creates one of the most amazing night sky views with several star trail observations. Watch the video HERE.

A Cheap Date

The MoonRise mission concept, in its most recent iteration, in cooperation with the Canadian Space Agency. The mission should fulfill a need to obtain a baseline sample of the 4 billion year-old South Pole-Aitken basin, only a small part of which spills over onto the Moon's nearside in line of sight with flight directors on Earth [NASA/NLSI].
Paul D. Spudis
The Once and Future Moon
Smithsonian Air & Space
Returning samples to Earth for analysis is one of planetary sciences’ holiest of grails. Although many different, complex measurements on returned samples are possible, one of the most important ones – from the standpoint of geologic study – is to determine the age of a rock.  Ages are determined by obtaining precision measurements of the amounts of different isotopes of certain elements (some of which are radioactive and decay at known rates).  By comparing the ratio of these radioactive elements to their daughter products, the amount of time that has elapsed since the rock formed can be calculated and thus, the age of that rock can be inferred.  If we know from which regional unit the rock comes, we can infer the ages of major events in planetary history.  This is one of the principal reasons why planetary scientists crave samples from other worlds.

We’ve determined the ages of most of the more than 380 kg of rock and soil samples returned from the Moon during Apollo.  Using that information and the geological mapping of the Moon from photographs, we were able to deduce the time sequence of major lunar and Earth-Moon system events.  Broad-scale, regional relations determined by remote mapping allowed us to identify the relative timing and significance of major units, while the returned rock samples allowed us to assign absolute ages to those same units.  The method proved so effective in reconstructing lunar history, that sample return became an idée fixe of the planetary science community, who strongly desired applying this approach to another planet.  Because questions surrounding its potential as a reservoir of life and because its nature permits the landing, retrieval and return (barely) of samples, Mars, with its complex, well mapped surface geology, was the object of most immediate interest.

When the planetary community wrote its recent “decadal survey” (a report outlining the highest priority robotic missions to undertake in the coming ten years), sample return came in as the highest priority for Mars (so high, that in effect, the decadal study told NASA to do a Mars sample return or do nothing).  Once Mars sample return was studied in detail, cost became an issue.  NASA robotic missions are classified according to the cost category they fall under.  The most expensive missions are “Flagship” missions, whose costs exceed $2 billion (the current MSL “Curiosity rover Flagship mission cost about $2.6 billion).  A Mars sample return would require not one but three separate Flagship-class missions: one to rove and collect the samples, another to launch the samples into orbit around Mars, and finally a mission to collect those samples from Mars orbit and return them to the Earth.  Using a variety of scenarios, the effort would cost over $10 billion, with a possible price tag exceeding $20 billion.  This staggering cost quickly shelved Mars sample return while planetary scientists scrambled for something to fill in a possible multi-decadal gap with no mission.

The question became, “Can a different and cheaper approach begin to address some of the key issues for which sample return is thought to be essential?”  Although many kinds of measurements can be done on returned samples, radiometric dating is one of the most critical and one thought to be possible only in laboratories on the Earth.  By using the absolute age of a single unit to bracket the timing of a host of different units mapped from remote sensing data, a single rock from a surface outcrop of a clearly defined unit of regional significance might enable us to calibrate the geologic time scale of Mars.
So the question before us is, “Is it possible to measure the absolute age of a rock remotely?”
Several groups around the country have been investigating the possibility of creating a small, portable laboratory for radiometric dating.  These instruments could be miniaturized and flown aboard a future robotic rover.  Rocks could be selected for analysis as the vehicle roams across the planet.  If such a rover were sent to areas of known geological context (e.g., a large, regional lava flow), rocks dated by the rover would define an absolute age for the flow.  A large lava flow would have numerous impact craters on it (the more densely a surface is cratered, the older it is).  For Mars, we now have to estimate (i.e., guess) how old its units are by comparing crater densities with those for lava flows on the Moon (from which the Apollo astronauts returned samples).  Although this approach is better than nothing, Mars has had its own cratering history and direct comparison to lunar history may not be valid.  A few solid absolute ages for lavas of widely varying age on Mars could “tie down” the cratering curve, such that we would not only date the flows we visit, but we could with precision, confidently estimate the ages of many other geological units not visited.

Indicative of a healthy and engaged science community, not all are convinced that ages obtained from an automated lab would be as useful as the high precision results that would be obtained from state-of-the-art terrestrial laboratories.  But a collection of imprecise ages from a variety of different units on Mars is better than no dates from any unit at all.  Given the astronomical costs and high technical risk of robotic sample return from Mars, the idea that we might be able to measure ages remotely looks increasingly attractive and practical.  This technique could also be applied to other planetary objects.  A properly equipped rover could make numerous measurements of the ages of craters and lava flows over a wide area on the Moon, where such information could be tied into the existing high-quality (but incomplete) lunar time scale.  Remote age dating would also be useful on planets from which launch of a sample return vehicle is nearly impossible, such as Venus (with a dense atmosphere and a very high surface gravity).

As sample return missions escalate in cost and difficulty, we should investigate how much can be learned about a planet’s history short of sample return.  A properly equipped robotic rover could blaze a new “Lewis and Clark Trail,” traversing large distances and making precision measurements along the way – returning information of inestimable value for a relatively low price.

Originally published at his Smithsonian Air & Space blog The Once and Future Moon, Dr. Spudis is a senior staff scientist at the Lunar and Planetary Institute. The opinions expressed are those of the author and are better informed than average.

Related Posts:
How the Mars community shot itself in the foot (March 10, 2012)
LROC: The Soviet lunar sampling missions (March 16, 2012)
The Last Sampler: Failure, then Success (March 17, 2012)
LROC: Retracing the steps of Apollo 15 / Constellation ROI (April 17, 2010)
The Rosetta Stone of the Solar System (November 19, 2009)
The Keepers of the Moon (July 8, 2008)

Thursday, August 23, 2012

Twin pools in small Southern Highlands crater

Two small melt flows solidified on the wall of a young crater, and melt pooled in its center. situated on the broad floor of the crater Orontius, in the bright southern highlands immediately east of Tycho. LROC Narrow Angle Camera (NAC) M188270580RE, LRO orbit 12806, April 5, 2012. Image field of view is 700 meters. See the larger original LROC Featured Image HERE [NASA/GSFC/Arizona State University].
Drew Enns
LROC News System

Impact melt commonly forms during impact events on the Moon due to the tremendous energy released during such events.

Melt often forms ponds on crater floors or in nearby exterior depressions, and forms flows as it travels downslope. Today's Featured Image of a young crater in the lunar highlands, at 40.875°S, 355.277°E, appears to have beautifully preserved examples of both forms!

Can we be sure the flows pointed out here are actually frozen impact melt and not debris flows?

LROC Wide Angle Camera (WAC) global mosaic overlaying LOLA topography shows the small bright crater, surrounded by a very bright landscape in the vicinity of Tycho, inside the west wall of Orontius at lower center. View the original LROC WAC context image accompanying the LROC Featured Image released August 21, 2012 HERE [NASA/LMMP/GSFC/Arizona State University].
One clue is that the flows are not very blocky when most of the crater wall is. Instead the flows appear to have entrained rocks when traveling over blocky sections of the crater. But debris flows can also pick up boulders along the way! Unlike the melt pond the flows do not have a cracked surface, perhaps indicating that formed as flows of granular material? On the other hand the flows have lower reflectance, typically of glasses that form on the surface of impact melt. It is difficult to say which hypothesis is correct without more information!

Can you find more evidence to argue for impact melt or debris flow in the full LROC NAC frame HERE?

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Wednesday, August 22, 2012

Cavuto: Gene Cernan is my hero

Apollo 17 commander Gene Cernan and FoxNews correspondent Neil Cavuto
from segment airing August 22, 2012. Video 4:04 HERE.
Neil Cavuto
Your World/FoxNews

Ok, I think I can die now.  I have spent a day with a guy who's been my hero all my life.

Full disclosure. I am fully biased. I think Gene Cernan is among the best of the best.  The last man to walk on the moon giving me unprecedented access to his world.  A world rich in heroes, and achievements, fighter planes, and rockets. A bygone era from a generation that never knew the word "can't."

I was still a boy when I watched Cernan having the time of his life on the that last visit by human beings to the moon.  Even as a kid, I could see the kid in Gene...A guy who didn't see his time up there as a "mission," but a "passion."

And one...that even drove he and colleague Harrison song.  I said Gene was a hero. I never said he was a singer.  I joked yesterday with Gene, as I have so often shared with many of you on this much I wanted to be an astronaut when I was a kid.

I did, I really did. I mean, I was a nut about it.  When other kids my age were collecting baseball cards, I was collecting astronaut autographs.  And reading everything I could get on every mission I could follow.

I had Gemini models, and Apollo models, lunar modules. Command modules. I'd pretend in my room, I was in a rocket in outer space.  Frankly, it worried my mom and dad.

But lo and behold it got them to do something that would forever change my life.

View the segment from Cavuto's "Your World," HERE.

LROC: Looking over a four-leaf clover..

Several shallow depressions, secondary craters, dot the surface of Mare Imbrium, in this case near a rocky ext Mons la Hire (near Euler and Lambert), and giving the impression of a four leaf clover. LROC Narrow Angle Camera (NAC) M190780929RE, spacecraft orbit 13158, May 4, 2012; resolution 1.5 meters and field of view 1500 meter across. View a larger cropped image HERE.  [NASA/GSFC/Arizona State University].
Drew Enns
LROC News System

These large, ~500 m diameter, depressions are characteristic of secondary impacts on the Moon. When a bolide (asteroid or comet) hits the surface of the Moon a crater forms at the impact site. To create a secondary crater material is ejected from the impact site at about a 45° angle. If the ejecta travels less than the escape velocity, it falls back down to the Moon. Since the escape velocity on the Moon (~2.4 km/s) is much lower than that at which bolides typically impact the Moon (10-20 km/s) secondary craters often have a distinctive appearance. These lower velocity impacts result in irregularly shaped craters. Sometimes secondaries land in clumps and create distinctive patterns, such as the "four leaf clover" whimsically identified in today's Featured Image.

Smaller scale context image shows the relationship of the out-cropping above with the larger Mons La Hires 30 km to the southeast.  Image width is 650 km, LROC WAC mosaic [NASA/GSFC/Arizona State University].
If the secondaries featured today were formed in another impact, which impact created them? The number of craters in our secondary group is fairly large, so the parent crater cannot be small. In the context image covering a slightly broader field of view below, other secondary chains (red arrows) appear to point to the southeast. Maybe zooming out further will reveal the mystery parent crater!

A quick look over the 605 kilometers from the southwestern tip of  the northwest Mons La Hire outcrop and the center of Copernicus, courtesy of the ILIADS application released by NASA/LMMP. The immediate and long-range legacy of the Copernicus event was lasting.
It looks like Copernicus is the parent crater! That makes sense. Copernicus fits our criteria. These secondary chains have been previously identified, but the fact that they were sourced from Copernicus crater hundreds of kilometers away is remarkable. The impact cratering process really is amazing.

Can you identify other secondary craters in the full LROC NAC frame, HERE?

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