Moon Observation Images
This picture of the Moon was taken with a telescope at Lick Observatory, California. Before rockets streaked to the Moon, scientists knew that the Moon had two major types of terrain.
The lighter terrain, called the highlands, is more heavily cratered and older than the darker, smoother maria a Latin word meaning "seas."
Many of the mountains in the highlands form large circles, called multi-ringed basins.
The basins were thought by almost all scientists to have been made when large objects crashed into the Moon. (Link Observatory Photo, Copyright UC Regents; used with permission.)
This is a view seen by Apollo 17 astronauts as they orbited the Moon. The maria are smoother, lower, and darker than the highlands.
The crater in the upper left is 20 kilometers across. (AS17-M- 1671)
Our knowledge increased dramatically beginning in 1969 when people rode great rocket ships to the Moon.
This shows the launch in 1972 of the Apollo 16 mission to a landing site in the highlands of the Moon. In all, there were six Apollo landings on the Moon.
In each case two astronauts descended to the Moon's surface while a third remained in orbit around the Moon in the main spacecraft called the Command and Service Module.
John Young, Commander of the Apollo 16 mission saluting the flag. The Lunar Module is behind Young, with the Lunar Roving Vehicle parked next to it.
This picture shows several interesting features about the Moon. First, Commander Young is wearing a space suit.
There is no air on the Moon, so astronauts must bring their life support systems with them. Notice that he has jumped about a meter off the ground, in spite of wearing the bulky space suit.
In fact, Young and his extraterrestrial outfit weighed 150 kilograms on Earth. If gravity was the same on the Moon, nobody could jump so far off the ground!
Also notice that there are no trees or bushes in sight, and the astronauts did not set up camp next to a babbling mountain stream.
There is no life or flowing water on the Moon. (AS16-113-18339)
Astronaut Harrison Schmitt driving the lunar dune buggy, officially called the Lunar Roving Vehicle, or LRV for short.
The Rover greatly enhanced lunar exploration on the last three Apollo missions by allowing much longer traverses around the landing sites. (AS17-147-22527)
One of the great advantages people have over robots is their wonderful ability to solve problems.
This slide shows how the Apollo 17 astronauts repaired a broken fender on their Rover by using a map and duct tape.
Without a fender, dust was being thrown both forwards and backwards, interfering with driving. (AS17-137-20979)
Many geophysical instruments were deployed on the Moon's surface. Each Apollo mission brought an array of scientific instruments with it.
They measured the composition of the very tenuous atmosphere, the strength of the magnetic field, and the nature of the interior.
The large object in the center of the slide is the central station, which sent data back to Earth.
The smaller, dark object to the left of the central station is the power supply needed to run the experiments (it used isotopes of plutonium),
and the shiny object in the foreground is a seismometer, which detected moonquakes. (AS16-113- 18347)
Harrison Schmitt examines a boulder at the Apollo 17 landing site. Geology is more than picking up rocks or whacking them with a hammer.
Geologists want to know how different rock types relate to each other. So, Schmitt and other astronauts examined large boulders carefully, sampling rocks from discernible layers.
They also tried to see where the boulders came from; in this case, the large rock rolled down from the top of a nearby hill. (AS17-140-21497)
This slide shows an astronaut collecting walnut-sized rocks with a rake.
The samples, aptly named "rake samples," proved to be extremely valuable because they provided a broad sampling of the rock types present at a landing site.
Some rock types were present only among rake samples. Also note the nature of the lunar surface. It is mostly powdery, with rocks distributed throughout it. (AS16-116-18690)
NASA stores lunar samples in pristine condition in the Lunar Curatorial Facility at the Johnson Space center in Houston, Texas.
The samples remain in the glass and steel cabinets, bathed in an atmosphere of pure nitrogen, which is relatively inert, so the samples do not alter by reaction with air. (S80-29345)
The skilled technicians who curate the lunar samples wear lint-free suits for cleanliness, but actually never handle the samples directly.
Instead, they pick them up and chip samples off them by using the black rubber gloves that protrude from the cabinets. (S82-26777)
This is a view of the farside of the Moon. The dark maria on the left are barely visible from Earth.
All the terrain to the right is on the farside and was completely unexplored until the space age.
The highlands are lighter in color than the maria, higher by a few kilometers on average, and intensely cratered. (AS16-M-3021)
This is a sample of anorthosite returned by the Apollo 15 mission. Anorthosites are composed almost entirely of one mineral, plagioclase feldspar.
One way a single-mineral rock forms is by accumulation by either floating or sinking in a magma.
Because anorthosite seems to be an abundant and widespread rock type in the lunar highlands, scientists believe that the Moon was surrounded completely by a huge ocean of magma
soon after it formed. (S71-42951)
This diagram depicts the magma ocean concept. When the Moon formed it was enveloped by a layer of molten rock (magma) hundreds of kilometers thick.
As that magma crystallized, the minerals more dense than the magma sank while those less dense (such as feldspar) floated, forming the anorthosite crust.
The dense minerals (olivine and pyroxene) later remelted to produce the basalts that compose the maria. (Graphics by Brooks Bays, University of Hawaii.)
After the first crust formed in the highlands, it was modified by the intrusion of other rock types. This one is called troctolite and is composed of olivine and plagioclase feldspar.
A large variety of rock types formed during this period. (S73-19459)
This is another photograph of the farside of the Moon. The dark splotch in the center is one of the rare maria on the farside.
It sits in a large crater (180 kilometers across) called Tsiolkovsky. Every crater visible in this photograph formed by the impact of objects into the Moon.
The photograph was taken by one of the Lunar Orbiter spacecraft that surveyed the Moon in the mid-1960s. (Lunar Orbiter III-121-M)
The Orientale Basin on the western limb of the Moon was formed by a large impact. About half of this eye-catching structure is visible from
the Earth. Note the concentric rings; most scientists believe that the third one is the actual crater rim. The diameter of the third ring is 930 kilometers.
There are about 40 such structures on the Moon (all larger than 400 kilometers across), and they may all have formed in a relatively narrow interval between 3.85 and 4.0 billion years ago.
(Lunar Orbiter IV-187-M)
With so many craters of all sizes in the lunar highlands, it is no wonder that the rocks have been modified by meteorite impact.
This sample was collected in the highlands by the Apollo 16 mission. It is a collection of rock and mineral fragments all mixed together.
Geologists call such rocks "breccias." Many of the rock fragments are themselves breccias; some, such as the dark fragments, were even melted by an impact. (S72- 37216)
This picture taken during the Apollo 15 mission shows lava flows in Mare Imbrium. The prominent lava flows that extend from lower left to upper right in this slide are
among the youngest on the Moon, a mere 2.5 billion years old! These flows are several hundred kilometers long. (AS15-M-1556)
Although eruption of most mare basalts did not produce volcanic mountains, there are a small volcanic domes in a few places. This shows the Marius Hills, a collection of relatively low domes.
Rilles (sinuous lava channels) are also visible, one of which cuts across a mare ridge. (Lunar Orbiter V-214-M)
This is a basalt sample returned by the Apollo 15 mission. The brownish color is caused mostly by the presence of the mineral pyroxene.
The holes are frozen gas bubbles called "vesicles", a common feature of terrestrial volcanic rocks. (S71-46632)
The river-like feature in this photograph is called a "rille." Apollo 15 landed near the rim of this rille (called Hadley Rille) between the two largest mountains.
Hadley Rille is 1.5 kilometers wide and 300 meters deep. Rilles are channels in which lava flowed during the eruption of mare basalts.
All samples collected from its rim are basalts, proving that flowing water did not form these river-like features. (AS15-M-1135)
Photograph at the Apollo 15 landing site, looking down into the rille.
The crew could have walked down into the rille and sampled rocks from its walls, but time and concern about their safety did not permit it. (AS15-85-11451)
For comparison with Hadley Rille, we see here a lava channel about 4 meters across on Kilauea Volcano, Hawaii, in 1986.
When it was active, Hadley Rille probably resembled this channel, although it was much larger. The lava cools on top, forming a darker skin.
Note the levees on the sides, which help confine flow to the channel. The cone in the distance is Pu'u O'o, the source of the lava.
(Photograph courtesy of Scott Rowland, University of Hawaii.)
Fire fountaining is another form of volcanic eruption. This one took place in 1959 at Kilauea Volcano and sent lava up to 550 meters into the air.
Such eruptions, called "pyroclastic" eruptions, produce loose fragments of hardened lava rather than lava flows.
Fire fountaining takes place when the magma contains a high concentration of gases (usually water vapor and carbon dioxide on Earth). (Photograph courtesy of National Park Service.)
Astronauts found a pyroclastic deposit on the Moon at the Apollo 17 landing site. The orange soil is composed of numerous droplets of orange glass that formed by fire fountaining.
Thin slice of some Apollo 17 orange soil. The view is 2.5 millimeters across. The small drops of lava did not have time to form minerals in it before it cooled,
so most of the droplets are composed of glass. The darker ones did have time to crystallize partially, and formed the mineral ilmenite,
which is opaque, and so appears black in this photograph. (Photograph courtesy of Graham Ryder, Lunar and Planetary Institute.)
This is the crater Alphonsis on the Moon. This large impact crater is 120 kilometers across.
The dark circular features on the floor of Alphonsis are cinder cones produced by pyroclastic eruptions.
They are lower (about 100 meters) and wider (10 to 20 kilometers) than cinder cones on Earth because the Moon's lower gravity and lack of air allow the particles to travel further.
This is a painting by artist and planetary scientist William Hartmann depicting the way most scientists believe the Moon formed.
Because all the traditional ideas for lunar origin had fatal flaws, Hartmann and other scientists devised the idea that the Moon formed as a result of the impact of
a projectile the size of the planet Mars with the almost completely constructed Earth. Both projectile and Earth already had formed cores and computer simulations of
the giant impact indicate that the core of the projectile gets added to Earth's iron core, thus accounting for the fact that the Moon has a tiny iron core.
Much of the rocky mantles of the Earth and projectile melted or vaporized. The material that ended up in orbit around the Earth then accreted to form the Moon.
(Photograph courtesy of William K. Hartmann.)
This is what Earthrise looked like from lunar orbit during the Apollo 11 mission.
One of the reasons for studying the Moon is to understand more about the origin and geologic history of the Earth.
The Moon provides information about how Earth formed, about its initial state, and about its bombardment history.
This information has been erased from Earth by billions of years of mountain building, plate motions, volcanism, weathering, and erosion. (AS11-44-6549)
People with imaginations envision large bases on the Moon.
This picture shows a complex installation with radio telescopes, launch site, mass driver (another type of launch facility), and a parent talking with a child,
perhaps explaining where their ancestors came from. (NASA painting by Pat Rawlings, Eagle Engineerng.)
although the Moon has no running water or air to breathe, its soil contains enormous amounts of oxygen.
This key element for life support and rocket propellants can be extracted from the surface materials by reaction with hydrogen (also present, though in small amounts).
It might be exported for use in earth orbit or to fuel spacecraft on tips to Mars and elsewhere in the Solar System.
Many other materials could be mined on the Moon, such as iron, aluminum, and titanium for use as building materials. (S83-28324)
A lunar base could be built up gradually. This artist's conception shows a habitat module being unloaded from an automated spacecraft.
The spherical objects are fuel tanks, which might use fuel produced on the Moon. (S84- 43855)
Professor Larry Haskin of Washington University in St. Louis has pointed out that besides the abundant oxygen present in every rock,
the Sun has implanted enough hydrogen, carbon, and nitrogen into the lunar soil to produce plenty of food.
So, although the lunar surface is dry and lifeless, each cubic meter of moon dirt contains the ingredients to make lunch for two: two cheese sandwiches on (of course) whole grain bread,
two plums, and two 12-oz sodas. (Photograph courtesy of Twyla B. Thomas.)
A key scientific task when people live and work at a lunar base will be field geology.
The real work of geology is done in the field, where geologists map rock distributions and observe both large- and small-scale features.
In the scene depicted here, astronauts are examining a lava tube, a common feature in basaltic lava flows on Earth and almost certainly present in flows on the Moon. (S88-33546)
One problem with exploration of either the Moon or Mars is that there is no breathable atmosphere. Astronauts are also exposed to dangerous radiation.
To get around these risks, but still make use of human intelligence, future space exploration will probably make use of telerobotics.
Such devices are a combination of autonomous robots and human operators, so a human brain can be present in the robot, even if located a thousand kilometers away.
In this way, people will be able to explore any region of the Moon without leaving the safety of their lunar base.
The robot's eyes are television cameras, so the remote operator sees, in stereo, what the robot sees.
When the operator turns his or her head, the robot turns its head, giving the operator the sense of being in the robot, a phenomenon called "telepresence."
Similarly, the operator can use the hammer to chip off rock samples, pick them up, examine them, and stow selected ones for return to a lunar base.
(NASA painting by Pat Rawlings, Eagle Engineering, based on a concept developed by Paul D. Spudis and G. Jeffrey Taylor.)
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NASA Educational Products Moon Slide Set