A blood moon is the first full moon after a harvest moon, which is the full moon closest to the fall equinox. Another name for a blood moon is a hunter’s moon.
Before the advent of electricity, farmers used the light of the full moons to get work done. The harvest moon was a time they could dedicate to bringing in their fall harvest. And so a month later is the blood moon, or the hunter’s moon. This was a good time for hunters to shoot migrating birds in Europe, or track prey at night to stockpile food for Winter.
A full moon occurs every 29.5 days, so a blood moon occurs about a month after the harvest moon. A blood moon is just a regular full moon. It doesn’t appear any brighter or redder than any other full moon. The distance between the Earth and the Moon can change over the course of the month. When the moon is at its closest, a full moon can appear 10% larger and 30% brighter than when it’s further away from the Earth.
A blood moon will actually turn red when it matches up with a lunar eclipse. These occur about twice a year, so blood moons match up with lunar eclipses about every 6 years or so. At the time of this writing, the next blood moon lunar eclipse will be in 2015.
Future lunar astronauts may want to brush up on their spelunking skills: the first lava tube has been discovered on the moon.
In a recent paper published in Geophysical Research Letters, Junichi Haruyama and colleagues report that they have discovered a mysterious hole in the lunar surface in high resolution images from the Kaguya spacecraft. The hole is 65 meters in diameter and is located in the volcanic Marius Hills region on the near side of the moon, right in the middle of a long sinuous rille. Sinuous rilles are thought to be formed by flowing lava, either on the surface or in enclosed lava tubes.
Of course, there are a lot of ways to form a hole in the surface of the moon. The most obvious is with an impact: the moon has literally been battered to pieces over the years by rocks from space. Couldn’t this hole be a fresh impact crater? Nope. Haruyama’s team observed the hole nine separate times, at various illumination angles, and even when the sun was almost directly overhead it looked mostly black, suggesting that it is very deep. They calculate a depth of around 88 meters, so the hole is deeper than it is wide. No impact crater is like that.
Four different views of the lava tube skylight at varying sun angles. Arrows indicate the direction of incident sunlight (I) and the viewing direction (V). Image credit: JAXA/SELENE
Another possibility is that the hole is due to some sort of volcanic eruption, but there is no sign of volcanic deposits like lava flows or ash emanating from the hole. The hole is isolated, so it isn’t likely to be due to a fracture in the lunar crust either – you would expect such a fracture to form a chain of holes.
Haruyama’s team concluded that the most likely explanation is that the hole that they discovered is a “skylight” – a location where the roof of a lava tube collapsed, either when the lava filling the tube flowed away, or later in the moon’s history due to an impact, moonquake, or tidal forces from the Earth. If it is a lava tube, their calculations based on the multiple images of the hole show that the tube could be 370 meters across.
Lava tubes are important in understanding how lava was transported on the early moon, but they are not just a scientific curiosity: they may also provide valuable refuges for future human explorers. The surface of the moon is not protected from the harsh radiation of space by a magnetic field or a thick atmosphere, so a long term human presence would be most feasible if astronauts could spend most of their time shielded underground. Digging a hole large enough to fit an entire moon colony in it would be a huge engineering challenge, but lava tubes could provide ready-made locations for a well-shielded base, making future astronauts the most technologically advanced cave-dwellers in history.
The first attempt to send a rocket to the Moon via balloon hit a snag on Monday. The first test of the Aeronautics and Cosmonautics Romanian Association’s (ARCA) balloon-launched rocket (or “rockoon”) ended in failure when the “inflation arms” used to fill the balloon became entangled in the balloon itself. The arms had to be cut, and the operation – which required the use of a large naval frigate — was curtailed. ARCA hopes to compete in the Google Lunar X PRIZE, and intends on using their unusual rocket system to send an equally unique spherical lunar lander to win a $30 million prize.
Rockoons were tried and then abandoned by the US in the 1950s because they blew off course in windy conditions.
ARCA’s European Lunar Explorer (ELE) is a simple design. The super-huge balloon carrying a system of three rockets will soar to about 11 miles (18 km) up. Then the first two rocket stages will fire and boost the system into low Earth orbit, and use the final stage to boost it to the Moon. The ELE will then travel to the moon and deploy its Lunar Lander, which resembles a knobby rubber ball that uses its own rocket engine to ensure a soft landing. Watch their video of how it all will work below: (If nothing else, watch it for the great music!)
On Monday, the Romanians loaded their prototype moon-balloon rocket onto the a large Romanian naval frigate, the Constanta, which took the entire crew out to the launch site in the Black Sea.
But as the balloon started to inflate, the inflation mechanism arms got tangled, and the entire operation had to be abandoned. The giant black balloon collects heat from the sun instead of using burners like hot-air balloons normally use, so it needs to launch during the day.
The Google Lunar X PRIZE challenges participants to construct a delivery system that will get a rover to the Moon, where the robot has to drive for about 500 meters, take high-resolution pictures of its surroundings, and then send them back home.
Artist concept of the Centaur and LCROSS heading towards the Moon. Credit: NASA
[/caption]
Water has long been suspected to exist in the permanently shadowed polar craters on the Moon, and now the LCROSS impact has allowed scientists to make a direct and definitive finding of this precious resource in a place NASA and other space agencies are considering exploring with human expeditions. Many say this could be a game-changing discovery for the future of lunar science and exploration. Unlike the previous announcement in September of water on the Moon, where water exists diffusely across the moon as hydroxyl or water molecules adhering to the surface in low concentrations, this new discovery could mean underground reservoirs of water ice. “There is too much water to be just absorbed in the soil,” said Anthony Colaprete of the LCROSS mission at Friday’s press conference. “There has to be real solid ice there. You could melt it and drink it.”
But could you really drink it? “Well, not if it has methanol in it. We need to sort out the flavor of the water,” said Colaprete, “meaning we need to find out if it is water, ice, or vapor. We still need to do that math.”
Colaprete said from the amount of water the spectrometers on the LCROSS spacecraft detected, initial indications are it is ice. However, Colaprete added that the impacting Centaur upper stage didn’t hit appear to hit something hard and frozen, from the images of the crater.
If someone was walking on the Moon and was able to walk in Cabeus crater where the impact took place, would the regolith there look different compared to other places on the Moon? “That’s a good question – and we’ve been talking about that,” Colaprete said. “It would be an interesting place to walk around. With our near infrared camera we can relate the the data to what the human eye can see, and try to understand what the terrain looks like. We never saw the crater floor before impact, but now we can see what the floor looks like.”
Did they find anything else in the plume created by the impact? “We’re seeing a lot of stuff,” Colaprete said. “I think there’s a little bit of everything. We’re seeing other emission lines in the spectroscopic data we haven’t completely identified. We’re still working on those — I don’t know what all else is in there just yet. We’ve been focusing on the water quest so far.”
As to whether they’re seeing any organics, the team couldn’t yet say definitively. Colaprete said they are seeing compounds similar to those seen previously in asteroids and comets.
“This is only another snapshot in time of our understanding of the moon,” said Mike Wargo, NASA’s chief lunar scientist, ” and we’ll be continuing to work to get more details on the water and everything else. We’re not done yet.”
You’ve seen the pictures, now watch the movie! Zoom into the Apollo 11 landing site with the Lunar Reconnaissance Orbiter’s latest images of Tranquility Base where humans took their first steps on the Moon. Thrill with the detail! Swoon with the history! Or, just enjoy it.
The LCROSS team announced today the mission successfully uncovered water during the Oct. 9, 2009 impacts into the permanently shadowed region of Cabeus cater near the moon’s south pole. “Indeed yes, we found water. We didn’t find just a little bit we found a significant amount,” said Tony Colaprete, principal investigator for LCROSS at a press conference. The team was not able to put a concentration of how much water is held in the lunar regolith, but in a fraction of the 20-30 meter crater the impact made, they were able to observe about 25 gallons (95 liters) of water with spectroscopic data. Colaprete held up a 2-gallon (7 liter) bucket, to demonstrate how much they found.
Asked if the team had “eureka” moment of when they found the water signature, Colaprete said, “It’s been a ‘holy cow!’ moment every day since impact. About two weeks ago we meet as a team and went through the entire data set. That’s when we came to the conclusion that we definitively found water.”
Colaprete said they also found signatures of other compounds as well, including sodium and carbon dioxide, which they are still analyzing.
While earlier findings this year of water on the Moon with the Moon Mineralogy Mapper on the Chandrayaan-1 spacecraft compared the lunar regolith to being drier than deserts on Earth, at Cabeus crater, there appears to be more.
“If you were standing on the 20 meter ‘beach,’ of the crater we created from the impact, it is wetter than some deserts on Earth,” Colaprete said.
Since the impacts, the LCROSS science team has been working almost nonstop analyzing the huge amount of data the spacecraft collected. The team concentrated on data from the satellite’s spectrometers, which provide the most definitive information about the presence of water. A spectrometer examines light emitted or absorbed by materials that helps identify their composition. Data from the ultraviolet/visible spectrometer taken shortly after impact showing emission lines (indicated by arrows). These emission lines are diagnostic of compounds in the vapor/debris cloud. Credit: NASA
The 95 liters was the amount of what was in the field of view of the spectrometers. To find out how much total water is inside the crater will take a “reconstruction” of the crater by the team. “We need to take the amount of ejecta, along with the size of crater and reconstruct the event to understand how it all fits back in the ground to understand everything in its entirety,” said Colaprete. “We know it was important to the public for us to come out with the results, and to provide some sort of quantifiable amount but we still have a lot of work to do to see the total picture.”
The impact created by the LCROSS Centaur upper stage rocket created a two-part plume of material from the bottom of the crater. The first part was a high angle plume about 10-12 meters across of vapor and fine dust and the second a lower angle ejecta curtain of heavier material. This material has not seen sunlight in billions of years.
Colaprete said the crater floor is normally about -230 C, but the impact heated things up to about 1000 K, or 700 C, which is cold for an impact, but what was expected for the low density Centaur rocket that slammed into the Cabeus Crater.
Where the water came from is yet to be determined, whether it was delivered there by comets and meteorite hits or if some process within the Moon or on the surface is creating the water.
Mike Wargo, NASA’s chief lunar scientist, said the cold traps in the permanently shadowed craters of the Moon are like the dusty attics or junk drawers of the solar system. “They collect stuff from the whole evolution of the solar system, at least form the past few billion years. We’re only just begun to tap into our understanding.”
“This has really turned our understanding of lunar water on its head,” said Greg Delory. We should keep our minds open of what this is telling us. It’s not Apollo’s Moon, its our Moon.”
JAXA, the Japan Aerospace Exploration Agency has released all the data from the Kaguya mission to the public. One of the ways to view the data is through a very nifty 3-D virtual brower. It only is available in Japanese for now (English version by the end of November, they say) so it is a little difficult to navigate, but once you figure it out, prepare yourself for loads of fun. First, you need Java. Then…
go to this page and download the browser. (If you don’t have Java, when you try to open the download it will ask you if you want to add Java.) When you get everything downloaded and the page opens up, (screenshot of page, above) look for the blue buttons on the top right. If you have a modern PC or laptop, click on the left blue button. If you have an old pre-Intel Mac, click the right blue button. Then again, it takes a while for the data to download. On the left are different data sets you can view from the different instruments. Unless you are familiar with the different instruments, it is kind of a crap shoot as far as what each one is; so just click one and see what comes up. The top one is for Clementine data, but the rest are from the different instruments on Kaguya. The Moon globe will fill in with data, and you can spin around and check out virtually any location on the Moon. It’s pretty wild, and addictive. If you still have a hard time figuring it out, you’ll have to wait for the English version. Or you can go to this page, which is a form where you can request what data you want to see. Enjoy!
Close-up view of Apollo 12 landing site from LRO. Credit: NASA/GSFC/Arizona State University
Wow! Just look at the detail visible in this image of the Apollo 12 landing site taken by the Lunar Reconnaissance Orbiter from its lower mapping orbit of 50 km above the surface. Compared to earlier images taken in September when LRO was in a higher orbit, the Lunar Module descent stage really stands out, as well as the Apollo Lunar Surface Experiment Package (ALSEP). Also visible are the trails left by spacewalking astronauts. From this and other LROC landing site images, it is clear that astronaut activity lowers the albedo, or reflectivity of the surface. Areas of heaviest activity have the lowest albedo, especially around the LM. NASA says this effect is most likely due to compaction of a very loose surface powder by the astronauts just walking around.
The Apollo 12 landing site as seen by LRO. Credit: NASA/GSFC/Arizona State University
Here is a slightly more zoomed out version that includes the Surveyor 3 spacecraft. The Sun is very high in the sky (incidence angle 4°) for these images and shadows are minimized.
Below is an image taken by the astronauts as they set up the ALSEP instruments.
The Apollo 17 Lunar Module Challenger descent stage comes into focus from the new lower 50-km mapping orbit, image width is 102 meters [NASA/GSFC/Arizona State University].
.”]
The Lunar Reconnaissance Orbiter maneuvered into its 50-km mapping orbit on September 15, which enables it to take a closer look at the Moon than any previous orbiter. This also allows for comparing previous images taken by LRO when it was at its higher orbit. Here’s the Apollo 17 landing site: just look at what is all visible, especially in the image below! These images have more than two times better resolution than the previously acquired images.
Region of Taurus-Littrow valley around the Apollo 17 landing site. NASA/GSFC/Arizona State University.
At the time of this recent pass, the Sun was high in the sky (28° incidence angle) helping to bring out subtle differences in surface brightness. The descent stage of the lunar module Challenger is now clearly visible, at 50-cm per pixel (angular resolution) the descent stage deck is eight pixels across (four meters), and the legs are also now distinguishable. The descent stage served as the launch pad for the ascent stage as it blasted off for a rendezvous with the command module America on December 14, 1972.
Also visible is the ALSEP, the Apollo Lunar Surface Experiments, which for Apollo 17 included 1) Lunar Seismic Profiling Experiment (geophones), 2) Lunar Atmospheric Composition Experiment (LACE) to measure the composition of the Moon’s extremely tenuous surface bound exosphere, 3) Lunar Ejecta and Meteorites (LEAM) experiment, 4) central station, 5) Heat Flow Experiment, 6) all powered by a Radioisotope Thermoelectric Generator (RTG). Below is how it looked from the surface, taken by the Apollo astronauts.
View of the ALSEP looking south-southeast. Credit: NASA
Compare these most recent images to one taken previously.
Zoomed in image of the impact plume. The extent of the plume at 15 sec is approximately 6-8 km in diameter. Credit: NASA
Nine science instruments on board the LCROSS spacecraft captured the entire crash sequence of the Centaur impactor before the spacecraft itself impacted the surface of the moon. But from Earth, any evidence of the plume was hidden by the rim of a giant impact basin, a 3 kilometer-high (2-mile) mountain directly in the way for Earth telescopes trained on the impact site, said Dr. Peter Schultz, co-investigator for LCROSS. Additionally, the crater created by the impact was only about 28 meters across (92 feet) but Schultz said the best resolution Earth telescopes can garner is about 180 meters (200 yards) across.
The science team is analyzing the data returned by LCROSS, and Anthony Colaprete, principal investigator and project scientist, said “We are blown away by the data returned. The team is working hard on the analysis and the data appear to be of very high quality.”
The team hopes to release some of their preliminary findings within the next several weeks, Schultz said at in webcast with students and teachers this week.
During the Oct. 9 crash in to the Moon’s Cabeus crater, the nine LCROSS instruments successfully captured each phase of the impact sequence: the impact flash, the ejecta plume, and the creation of the Centaur crater.
Within the ultraviolet/visible and near infra-red spectrometer and camera data was a faint, but distinct, debris plume created by the Centaur’s impact.
“There is a clear indication of a plume of vapor and fine debris,” said Colaprete. “Within the range of model predictions we made, the ejecta brightness appears to be at the low end of our predictions and this may be a clue to the properties of the material the Centaur impacted.”
The magnitude, form, and visibility of the debris plume add additional information about the concentrations and state of the material at the impact site.
From images and data, the team was able to determine the extent of the plume at 15 seconds after impact was approximately 6-8 km in diameter. Schultz said the Moon’s gravity pulled down most of ejecta within several minutes.
The LCROSS spacecraft also captured the Centaur impact flash in both mid-infrared (MIR) thermal cameras over a couple of seconds. The temperature of the flash provides valuable information about the composition of the material at the impact site. LCROSS also captured emissions and absorption spectra across the flash using an ultraviolet/visible spectrometer. Different materials release or absorb energy at specific wavelengths that are measurable by the spectrometers. the locations of the Diviner LCROSS impact swaths overlain on a grayscale daytime thermal map of the Moon’s south polar region. Diviner data were used to help select the final LCROSS impact site inside Cabeus Crater, which sampled an extremely cold region in permanent shadow that can serve as an effective cold trap for water ice and other frozen volatiles. Credit NASA/GSFC/UCLA
Additionally, the Lunar Reconnaissance Orbiter’s Diviner instrument also obtained infrared observations of the LCROSS impact. LRO flew by the LCROSS Centaur impact site 90 seconds after impact at a distance of ~80 km. Both science teams are working together to analyze the their data.
The LCROSS spacecraft captured and returned data until virtually the last second before impact, Colaprete said, and the thermal and near-infrared cameras returned excellent images of the Centaur impact crater at a resolution of less than 6.5 feet (2 m).
“The images of the floor of Cabeus are exciting,” said Colaprete. “Being able to image the Centaur crater helps us reconstruct the impact process, which in turn helps us understand the observations of the flash and ejecta plume.”
