Map of Moon water; blue indicates higher concentrations of detected water molecules. Credit: NASA/Moon Mineralogy Mapper instrument.Here it comes! A veritable tidal wave of discovery on Earth's Moon….

In one short week, NASA's LCROSS (Lunar Crater Observation and Sensing Satellite) mission will quite literally come to an end—a fiery, spectacular end as it deliberately crashes into the lunar South Pole crater Cabeus A in hopes of kicking up enough material for us to detect the presence of water. If you want to see the action as it happens, come up to Chabot Space & Science Center on Friday morning, October 9, 3:00 AM to watch NASA's live simulcast and–weather and the gods of astronomy permitting–the view through Chabot's 36-inch telescope, "Nellie."

In recent months, NASA has been sending a lot of acronyms—excuse me: spacecraft—to the Moon: LRO with it's LROC, LEND, and LOLA instruments; LCROSS (which I've heard some call "LaCROSS," for the record) with its VIS, NIR, MIR, TLP, VSP, NSP—oh, the list goes on!

The fact of the matter is MOON spells "Moon." Whether or not we do end up returning humans to the Moon in the next decade, which is partly what reconnaissance by LRO and LCROSS and their arrays of acro-instrumentation is for, there are still things to be learned about our nearest neighbor in space—and water is the word at present.

Even as LCROSS and its Centaur-booster-rocket-turned-lunar-clobbering-device follow their final fatal trajectory toward Cabeus A, its launch buddy LRO, now in an orbit around the Moon and beginning to send back scientific results and images, may have already detected telltale signs of the wet stuff—which on the Moon won't be wet, but frozen solid, of course; liquid water cannot persist in the Moon's airless environment.

LRO's LEND (Lunar Exploration Neutron Detector) instrument is designed to find signs of water molecules by measuring neutron radiation emanating from the lunar surface. The Moon is constantly bombarded by high energy cosmic radiation, which forms radioactive isotopes in the soil that in turn emit neutrons. By measuring the abundance and speed distribution of the neutrons, details of soil chemistry can be inferred. The presence of light atomic nuclei–in particular the lightest of all, hydrogen, a component of water—in the soil reduces the levels of neutron emission. That drop in neutron radiation is the telltale scientists are looking for.

While LRO scientists want to make further measurements before concluding the presence water ice concentrations, observations from three other spacecraft—NASA's M3 instrument (Moon Mineralogy Mapper) aboard India's Chandrayaan-1 spacecraft and the Cassini and EPOXI spacecraft—have mutually confirmed the presence of water and hydroxyl molecules (hydroxyl is a water molecule missing one of its two hydrogen atoms) in the soils of the Moon, across much wider expanses than the confines of dark polar crater floors.

Cassini and EPOXI made measurements as they flew past the Moon to their respective destinations (Saturn, and a comet), and measurements have been made by M3 from lunar orbit. The detection of water by these spacecraft doesn't mean seas of liquid or glaciers of ice, or even blanketing layers of gaseous water vapor, but rather relatively small amounts of water and hydroxyl molecules attached to, or "stuck to," other materials in the top few millimeters of soil.

This thin "confetti" of water molecules appears to come and go with lunar daytime, forming during the cold, dark two-week-long lunar night and diminishing under the baking light of the Sun.

So, right now, MOON spells water (M3 et al), water (LRO), and possibly more water (LCROSS, on October 9th)—at least, the evidence seems to be mounting!

The LCROSS satellite, launched on June 18th, is slowly making itself ready to smack into the moon in late October. A plume of dust 37 miles high will be produced, which may be visible from Earth (most likely Hawaii). The envy of the Mythbusters, this explosion is designed to find water in permanently shadowed areas of the moon. Much has been written on LCROSS, from historical perspectives to cost containment.

As the impact grows closer, NASA is making an effort to talk about the locally driven mission. Many of the upcoming talks are suitable for any audience, from kids to adults.

Luna Philosophie: Hitch-hiking to the Moon

Where: Scribd, 539 Bryant St. (2nd Floor), San Francisco

When: Wednesday, 9/23 6-8 PM

Cost: Free, RSVP to Delia.L.Santiago@nasa.gov

Details: Dr. Kim Ennico, LCROSS Payload Scientist and the LCROSS Payload Integration & Test Manager, will provide an overview of the NASA LCROSS mission and discuss how NASA has been expanding the concept of “participatory exploration” with LCROSS as an example. This will be a lively discussion.

Andrew Chaikin on LCROSS

Where: Chabot Space & Science Center

When: Saturday, 9/26 3-430 PM

Cost: Free with Museum Admission

Details: Author, speaker, and space journalist Andrew Chaikin joins Chabot visitors for a night of moon conversation and exploration. Using the detailed program Google Moon, which he helped to develop, Chaikin takes the visitor on a guided tour of the moon’s surface. Chaikin will also discuss the recent LCROSS mission and his extensive knowledge of the Apollo missions.

To the Moon: A Look at NASA’s Upcoming Lunar Impact Mission and the History of Moon Exploration

Where: Exploratorium

When: Sunday, 9/27 2-4 PM

Cost: Free with Museum Admission

Details: Take a trip to our nearest neighbor in space with renowned science journalist and space historian Andrew Chaikin. Relive the achievements of Apollo lunar astronauts and learn about the ambitious LCROSS mission, which will send a rocket crashing into the moon’s permanently shadowed regions to kick up huge plumes of debris in the hopes of uncovering deposits of ice. In addition, Exploratorium educators will give an entertaining and interactive overview of moon science.

QUEST on KQED Public Media.

Neil Armstrong’s left boot print on the Moon—the celebrated ‘one small step’. Credit: NASA
What were you doing 40 years ago, on July 20th, 1969, when the first human foot (booted, not bare) made its impression on the gritty surface of the Moon? That is, if you're over 40 yourself….

I was in Oakland, lying on the green carpet of my family's living room floor, watching our black and white Zenith television set—the kind that would take a minute or so to warm up before delivering the handful of local VHF TV broadcasts within range of our aerial antenna.

Right. It was definitely another era. As archaic as the telecommunications technology may sound to those born after, oh, 1980, it was nevertheless the Space, not Stone, Age…. Never forget, the Apollo 11 landing on the Moon was the culminating moment of the whole adventure that started the Space Age.

It didn't really matter that our Zenith was a b/w set, as all the images from Apollo 11 and the Moon's surface were transmitted in black and white anyway. My eyes were riveted to the TV, the grainy, fuzzy image of the Eagle's landing strut and ladder as yet empty.

"What's taking them so long?" I complained impatiently (I was seven years old). I remember waiting for what seemed a couple of hours for the astronauts to come out.

"They're probably playing poker inside," was my dad's reply. I don't recall if I believed him or not. Finally, there was a booted foot at the top of the ladder, attached to the bulky white and gray form of a human in a space suit—Neil Armstrong, of course. And, history was made—twice: Buzz Aldrin came down the ladder soon after.

Some of you younger crowd may have been born into a world where humans walked on the Moon a long time ago, but I was born around the time it was actually happening. (In fact, I was born the year after the first human went into space; similarly my grandfather was born the year of the Wright Brothers' first aerial success—how time flies….)

On Monday, we not only mark four decades since that singular historic event, we do so at a time when there are plans afoot for humans to step onto the Moon once again.

Several robotic probes have gone Moonward in recent years, paving the way: Clementine, Lunar Prospector, and only last month the Lunar Reconnaissance Orbiter (LRO) and the Lunar Crater Observation and Sensing Satellite (LCROSS) were launched in tandem. LRO will give us our most detailed and comprehensive view of the Moon's surface appearance and conditions to date, and will help to identify future possible landing sites. LCROSS will look for water ice in a crater floor at the Moon's South Pole by impacting it with an empty booster rocket and studying what is blasted skyward. Water on the Moon would be a resource to future human missions far more valuable than gold.

Neil's left boot print is still up there, next to the Eagle's landing foot, most likely as fresh and new looking as when it was made (unless it got bulls-eyed by a one in a million meteorite strike!).

As there is no air, and thus no erosion, on the Moon, the print serves equally well as a monument to that decades-ago venture, or as a logo for the enterprise of our return. Fitting, too, as the Moon could serve as a stepping stone to destinations beyond….

Credit: NASA.

When the LCROSS satellite, nicknamed Centaur, smacks into the south pole of the moon in late October, it is expected to produce a plume of dust 37 miles high, which may be visible from Earth with a good backyard telescope. It will be visible in an arc from Hawaii to Texas.

If you'd like to catch the impact, the Chabot Space and Science Center in Oakland is hosting a Shooting the Moon star party on the night of impact. Morrison Planetarium in San Francisco may host a star-gazing event, as well, but it hasn't been announced yet. And you could check in on other observatories in the Bay Area, as well: Lick observatory in the Santa Cruz mountains, Foothill observatory in Los Altos Hills, Sonoma State observatory in Rohnert Park, and the Fremont Peak observatory in the East Bay.

Not all of them will be open to the public; for instance, Foothill Observatory will be closed to the public, because they’ve been asked to take photographs of the event.

If you know anyone with a 10-inch telescope (that's the diameter of the lens), you can bet that telescope will be lined up to look skyward when the LCROSS probe hits the moon.

If the impact goes well, then the plume above the moon's surface could hover there for hours. It will make its own crater on the moon about 6 feet deep and 30 yards wide, so the plume of dust will not be visible to the naked eye, or even through binoculars.

The exact date, time and even the exact location of the impact have not yet been determined. Keep your eye on NASA's site for more information.

And one aside: This impact will not hurt the moon, or send it off its orbit. That may seem apparent to many people, but NASA Ames officials say those are the most-asked questions about the project.

Listen to the Crash Landing radio report online.

Artwork from Jules Verne’s 1865 novel, From the Earth to the MoonLaunching a spacecraft bound for the Moon with the deliberate intention of striking the Moon in a spectacular impact!

Sounds like something out of a Jules Verne novel… but that's exactly what NASA's up to this year with the upcoming LCROSS (Lunar Crater Observation and Sensing Satellite) mission, scheduled for launch on June 2nd and impact sometime in October– exact date TBA.

And it's not unprecedented, either: the Lunar Prospector spacecraft back in 1998/1999, whose instruments detected possible signs of water ice in craters around the Moon's poles, was crashed into the Moon's South Pole at the end of its mission. The aim was to blast up a cloud of material from the lunar surface and spectroscopically analyze the plume in search of water vapor. None was detected then, but that's where LCROSS comes in.

LCROSS will seek to verify the presence or absence of water ice and related hydrated materials buried at the bottom of a permanently shadowed crater floor on the Moon's South Pole. Water ice cannot persist on any part of the Moon's surface that is subjected to sunlight, but because of the Moon's low axial tilt with respect to the ecliptic (the Sun's apparent annual path in the sky)– only about 1.5 degrees– there are craters at the Moon's poles whose floors never see the light of day, all month long and year round. Water ice could persist near the surface in these places.

LCROSS consists of two pieces: a "Shepherding Spacecraft" that will guide the whole affair to the proper location on the Moon's South Pole, and the Centaur rocket stage that propelled the spacecraft to the Moon. The pair will separate, and the Centaur rocket will become the primary impactor, striking ground and producing a crater and plume of ejected material. Viewing the event from above, the Shepherding Spacecraft will use cameras and other instruments to analyze the plume from a distance, and will then follow the same course as the Centaur, descending four minutes after impact through the ejected plume and analyzing material samples as it falls.

Then, the Shepherding Spacecraft, too, will impact the Moon– and the plume it kicks up may well be visible through modest sized telescopes on Earth. We're planning to watch the explosion live through our telescopes at Chabot, weather permitting. Keep an eye on our website for details.

Now, back to Jules Verne for a moment. The launching of a projectile with the intent of striking the Moon was indeed the subject of one of his novels, From the Earth to the Moon, published in 1865. Fired from an enormous cannon, the goal of that post Civil War mission was to catch the attention of anyone living on the Moon, to open up a line of communication with their civilization.

My wife asked me if crashing a probe into the Moon would have any harmful effects, particularly if in fact there is any form of life (subsurface microbes or such) living there. Well, certainly, if you happen to be a lifeform living at ground zero of the impact… but the fact is the Moon is frequently struck by meteorites much larger than the LCROSS impactor anyway. To paraphrase Douglas Adams, "that kind of thing goes on all the time."

One last fun tidbit about the Jules Verne novel: the launch site for his cannon-fired projectile was a place in Florida, 50 miles south of Tampa Bay, and only about 135 miles from the Kennedy Space Center, from which LCROSS will be launched…

A scale model of the LCROSS payload.

Update: This Friday morning, October 9th at 4:30AM PDT, the upper stage of the Centaur rocket carrying LCROSS will smash into a crater near the moon's south pole. The LCROSS spacecraft will follow close behind, making measurements and taking images of the emerging lunar debris before it too meets its dramatic end. Soon thereafter, we may learn if water can in fact be mined from the dark, cold lunar depths. For you moon junkies, NASA Ames Research Center in Moffett Field is also hosting an "LCROSS Impact Night"this Thursday, beginning at 7PM.

With a price tag of 80 million dollars and a little more than two years in the making, the LCROSS spacecraft will begin its voyage atop an Atlas V rocket. Shortly thereafter it will shepherd the upper stage of the rocket in an orbit around the moon to position it in place for a colossal impact that will kick up a cloud of lunar dust forty miles high. The goal is to see if water exists on the moon and if it does, buried deep beneath the lunar soil, accumulating over millions of years of impacts with comets, it would accelerate our efforts to establish a permanent lunar base. Think of it as a rest stop to refuel (oxygen is an essential ingredient of rocket fuel) before arriving at the next closest planetary body, Mars, a journey which takes roughly 600 days, or 200 times longer than a trip currently to the Moon from Earth.

The avid QUEST viewer may recall that we covered the LCROSS mission in the first episode of QUEST back in 2007. A lot has happened since then, including most notably a change in the launch date which at the time of this post was scheduled for May 20th, 2009. Peter Schultz's vertical gun range has been outfitted with some dizzyingly high-tech cameras, which are capable of recording at tens of thousands of frames per second (one can record at one million frames per second) to capture the most minute progressions of the lunar impact simulations performed with the thirty-foot tall vertical gun. The suite of nine instruments aboard LCROSS, known as its "payload", has been mercilessly subjected to thermal, vibration and acoustic testing to make sure they can withstand the effects of launch and the harsh celestial environment. And then there's the spacecraft itself which we weren't able to show you in 2007 because the spacecraft still had to be transformed from a set of designs into a compact, robust structure the size of a small car by a team of sharp, young Northrop Grumman engineers. Moreover, amateur astronomers, armed with telescopes ten inches or more, are now being encouraged by NASA to share their images of LCROSS' historic lunar impact.

One of the most impressive attributes of the LCROSS mission is its rapid turnaround and cost containment which in turn highlight the innovative production model that was essential in making LCROSS a reality. Imagine the spirit of Silicon Valley, with its entrepreneurial zeal and efficiency, fusing with some of the sharpest minds in astrophysics and aeronautical engineering, and you have a glimpse of the unique nature of this small but nimble mission which just may forever change our understanding of the moon and its secrets.

Watch the LCROSS Rocket to the Moon" television story online.

A limb shot of Mercury's horizon taken by the
MESSENGER spacecraft on January 14, 2008.
Photo Credit "NASA/MESSENGER"

If you can take a name like "Mercury Surface, Space Environment, Geochemistry and Ranging" and craft it into a neat acronym like MESSENGER, then you may have a future working with NASA….

And no, this blog isn't about NASA acronymizations, but rather the heat-resistant robot behind one of them. MESSENGER is the space probe that NASA sent to Mercury to give the Solar System's innermost planet the first up-close look since 1975, when Mariner 10 flew by.

Though MESSENGER's main mission will begin in earnest when it returns to Mercury and finally settles into an orbit around the planet, on March 18th 2011, we were given a tantalizing peak last January 14th when the probe made its initial flyby.

What did this quick, on the fly snapshot tell us that we didn't know before? Well-a lot, considering Mercury has been one of the least understood planets in the Solar System, and was for a long time thought to be similar in character to our own Moon. Mercury is shaping up to be a lot less like Earth's Moon than its gray, cratered, airless appearance would mislead.

One key difference: density-how much material is packed into the planet; or how heavy a standard sized chunk of it would be. Our Moon is a lightweight on this score, with an average density of only 3.4 grams per cubic centimeter, while Mercury weighs in at a hefty 5.427 g/cc-almost as dense as Earth.

Another key difference: magnetic field. Planets like Earth and the Gas Giant worlds (Jupiter et al) generate respectable magnetic force fields, useful for everything from deflecting plasma flowing from the Sun (the "solar wind") to properly directing magnetic compass needles. Venus, Mars, and our Moon do not possess magnetic fields worth mentioning, as it turns out.

Mercury, on the other hand, does. Planetary magnetic fields are believed to be generated by currents in a planet's liquid outer core-like how the electric current in the wire coil of an electromagnet generates a magnetic field. Mercury's magnetic field suggests it still has some activity in its core-molten metals circulating in currents as the core slowly cools off. And speaking of Mercury's core, it appears to comprise 60% of the planet's mass-about twice what is "typical" for Terrestrial (solid) planets.

I've often imagined Mercury to be a cosmic goldmine, with its apparent richness in metals and its density. I wonder if an astronaut could just walk along and pick up chunks of gold from its surface….

Another interesting find by MESSENGER is that some of the flat plains on Mercury may have been formed by volcanoes, long ago. In particular, MESSENGER imaged a number of volcanoes along the edge of the Caloris Basin, a large impact basin-one of the largest in the Solar System, at 1550 kilometers across.

The news coming out of the innermost region of the Solar System makes me giddy. Too bad I have to wait until 2011 for my next look at Mercury. These things take time.

Depiction of a major alignment of
the five visible planets in 1059 BCE.

Photo By Ben Burress

There are some pretty good "lineups" coming soon to skies above you.

First of all, "lineups," or alignments, go on in the heavens all the time, though most often they are alignments of objects too faint to easily notice, if at all. With that said, this summer holds some significant alignments of some of the brightest objects in the sky.

First on my hit list is the upcoming Saturn-Mars "near-miss". Though these two planets are not coming physically close to each other (the closest actual distance they come to each other is about 750 million miles), they will align so closely along the same line of sight that on July 11^th they will appear only ¾ of a degree apart-that's not much greater than the width of a Full Moon. The best time to see this pairing is after sunset on the evenings of July 10, 11, and 12, over the western horizon.

The next big ticket alignment is on August 1^st, when the Moon and the Sun occupy the same spot in the sky-the event we call a Total Solar Eclipse. As it happens, we won't be able to see this eclipse directly from the United States, as it will only be visible in Asia. However, NASA will be broadcasting live coverage of the eclipse from Northern China. We'll be showing NASA's broadcast in our planetarium at Chabot Space and Science Center, in case you'd care to come up and enjoy the spectacle. Don't let the fact that the live event goes on around 4:00 AM keep you away…it's worth getting up for!

A bit further out on the calendar is the September alignment of three planets: Venus, Mars, and Mercury. In the dusky twilight of mid-September evenings the three will be gathering. The closest grouping of the trio is on September 11^th, when they will be within about three degrees of each other-close enough that you can just about cover all three with your thumb. Mercury and Mars won't be very bright in the twilight-but Venus, bright enough to spot easily, can help guide your eye to the other two. Using a pair of binoculars will help a lot-but make sure you don't point them that way until after the Sun sets….

In ancient times (and in some cases not so ancient times), different cultures around the world have viewed alignments like these in different ways. Eclipses-both solar and lunar-were regarded by many cultures as bad omens, or bad occurrences (such as the Sun being devoured by a celestial animal-dragon, dog or other-in the case of a solar eclipse).

Planetary alignments were also given special consideration, sometimes being regarded as auspicious (for good or bad-usually the latter). One major alignment of the five visible planets (February 26, 1953 BCE) was believed to have "mandated" the creation of the Hsia Dynasty in China-the first great Chinese Dynasty. (Then, four centuries later, Mars, Mercury, Jupiter and Saturn apparently conspired to bring down that same dynasty-at least, their alignment on December 20, 1576 BCE was interpreted as an indicator of the dynasty's corruption, and it was overthrown by a revolt of believers…).

However you regard the lining up of celestial bodies (astronomically, astrologically, or aesthetically), these alignments are pleasing to watch, and times to reflect upon the constant and cyclic movement among the heavens. Enjoy….