Posted on by David Dickinson

How Amateur Astronomers Can Help LADEE

An Artist's concept of LADEE in orbit around the Moon. (Credit: NASA Ames).

You can help NASA’s upcoming lunar mission.

NASA’s Lunar Atmosphere and Dust Environment Explorer (LADEE) is slated to lift off from Wallops Island this September 5th in a spectacular night launch. LADEE will be the first mission departing Wallops to venture beyond low Earth orbit. A joint collaboration between NASA’s Goddard Spaceflight Center & the AMES Research Center, LADEE will study the lunar environment from orbit, including its tenuous exosphere.

Scientists hope to answer some long standing questions about the lunar environment with data provided by LADEE. How substantial is the wispy lunar atmosphere?  How common are micro-meteoroid impacts? What was the source of the sky glow recorded by the Surveyor spacecraft and observed by Apollo astronauts before lunar sunrise and after lunar sunset while in orbit?

Glows of the solar corona and crepuscular rays reported by the Apollo 17 astronauts in lunar orbit. (Credit: NASA).
Glows of the solar corona and crepuscular rays reported by the Apollo 17 astronauts in lunar orbit. (Credit: NASA).

The micro-meteoroid issue is of crucial concern for any future long duration human habitation on the Moon. The Apollo missions were only days in length. No one has ever witnessed a lunar sunrise or sunset from the surface of the Moon, as all six landings occurred on the nearside of the Moon in daylight. (Sunrise to sunset on the Moon takes about two Earth weeks!)

And that’s where amateur astronomers come in. LADEE is teaming up with the Association of Lunar & Planetary Observers (ALPO) and their Lunar Meteoritic Impact Search Program in a call to watch for impacts on the Moon. These are recorded as brief flashes on the nighttime side of the Moon, which presents a favorable illumination after last quarter or leading up into first quarter phase.

We wrote recently about a +4th magnitude flash detected of the Moon on March 17th of this year. That explosion was thought to have been caused by a 35 centimetre impactor which may have been associated with the Eta Virginid meteor shower. The impact released an explosive equivalent of five tons of TNT and has set a possible new challenge for Moon Zoo volunteers to search for the resulting 6 metre crater.

An artist's illustration of a meteoroid impact on the Moon. (Credit: NASA).
An artist’s illustration of a meteoroid impact on the Moon. (Credit: NASA).

We’ve also written about amateur efforts to document transient lunar phenomena and studies attempting to pinpoint a possible source of these spurious glows and flashes on the Moon observed over the years.

NASA’s Meteoroid Environment Office is looking for dedicated amateurs to take part in their Lunar Impact Monitoring campaign. Ideally, such an observing station should utilize a telescope with a minimum aperture of 8 inches (20cm) and be able to continuously monitor and track the Moon while it’s above the local horizon. Most micro-meteoroid flashes are too fast and faint to be seen with the naked eye, and thus video recording will be necessary. A typical video configuration for the project is described here. Note the high frame rate and the ability to embed a precise time stamp is required. I’ve actually run WWV radio signals using an AM short wave radio transmitting in the background to accomplish this during occultations.

Finally, you’ll need a program called LunarScan to analyze those videos for evidence of high speed flashes. LunarScan is pretty intuitive. We used the program to analyze video shot during the 2010 Total Lunar Eclipse for any surreptitious Geminid or Ursid meteors.

Brian Cudnik, coordinator of the Lunar Meteoritic Impact Search section of the ALPO, noted in a recent forum post that we’re approaching another optimal window to accomplish these sorts of observations this weekend, with the Moon headed towards last quarter on June 30th.

An example of an impact flash recorded by the Automated & Lunar Meteor Observatory video cameras based at the Marshall Spaceflight Center in Huntsville, Alabama.
An example of an impact flash recorded by the Automated & Lunar Meteor Observatory video cameras based at the Marshall Spaceflight Center in Huntsville, Alabama.

Interestingly, the June Boötids are currently active as well, with historical sporadic rates of anywhere from 10-100 per hour.  In 1975, seismometers left by Apollo astronauts detected series of impacts on June 24th thought to have been caused by one of two Taurid meteor swarms the Earth passes through in late June, another reason to be vigilant this time of year.

Don’t have access to a large telescope or sophisticated video gear? You can still participate and make useful observations.

LADEE is also teaming up with JPL and the Lewis Center for Educational Research to allow students track the spacecraft en route to the Moon. Student groups will be able to remotely access the 34-metre radio telescopes based at Goldstone, California that form part of NASA’s Deep Space Communications Network. Students will be able to perform Doppler measurements during key mission milestones to monitor the position and status of the spacecraft during thruster firings.

And backyard observers can participate in another fashion, using nothing more than their eyes and patience. Meteor streams that are impacting the Moon affect the Earth as well. The International Meteor Organization is always looking for information from dedicated observers in the form of meteor counts. The Perseids, an “Old Faithful” of meteor showers, occurs this year around August 12th under optimal conditions, with the Moon only five days past New. This is also three weeks prior to the launch of LADEE.

Whichever way you choose to participate, be sure to follow the progress of LADEE and our next mission to study Earth’s Moon!

-Listen to Universe Today’s Nancy Atkinson and her interview with Brian Day of the NASA Lunar Science Institute.

-Also listen to the 365 Days of Astronomy interview with Brian Day and Andy Shaner from the Lunar Planetary institute on the upcoming LADEE mission.

Posted on by Jason Major

NASA’s Lunar Orbiter Gets an Art Lesson with Lasers

In the ultimate example of science imitating art, engineers working with NASA’s Lunar Reconnaissance Orbiter recently beamed an image of the Mona Lisa to the LRO and back via laser beam in order to measure the rate of transmission between the spacecraft and Earth. This allowed them to then calibrate their software to correct for any discrepancies between the image sent and the one received, resulting in a picture-perfect result.

Leonardo would definitely have approved.

From NASA’s Goddard Space Flight Center:

As part of the first demonstration of laser communication with a satellite at the moon, scientists with NASA’s Lunar Reconnaissance Orbiter (LRO) beamed an image of the Mona Lisa to the spacecraft from Earth.

The iconic image traveled nearly 240,000 miles in digital form from the Next Generation Satellite Laser Ranging (NGSLR) Station at NASA’s Goddard Space Flight Center in Greenbelt, MD, to the Lunar Orbiter Laser Altimeter (LOLA) instrument on the spacecraft. By transmitting the image piggyback on laser pulses that are routinely sent to track LOLA’s position, the team achieved simultaneous laser communication and tracking.

“This test, and the data obtained from it, sets the stage for future high data-rate laser communications demonstrations that will be an essential feature of NASA’s next Moon mission: the Lunar Atmosphere and Dust Environment Explorer.“

Video: NASA/GSFC

Posted on by Andy Tomaswick

NASA Looks Towards Next Mission to the Moon

NASA’s Lunar Atmosphere and Dust Environment Explorer (LADEE) Observatory sits beside a radio frequency antenna inside an enclosure that blocks external static to detect electromagnetic emissions. Image credit: NASA Ames

With the GRAIL mission ending today, NASA is preparing for its next lunar orbiter mission, which could help pave the way for a potential future human mission to the Moon. While the Moon seems to be an ‘on-again-off-again’ potential human destination, as the GRAIL mission points out, studies of our closest neighbor in space continues to reveal surprises.

But if we are ever going to establish any sort of long-term presence on the Moon, scientists and engineers will have to understand more about the environmental conditions that they’re dealing with. Lunar dust is an environmental factor that requires much more exploration and study, as it may pose one of the biggest problems for humans on the Moon. Lunar dust is as fine as talcum powder and abrasive enough to cause long term problems to the lenses and seals central to the operation of mechanical equipment — not to mention hazards to human health — during any lengthy stay on the Moon.

Artist concept of the LADEE spacecraft in orbit at the Moon. Credit: NASA

To study this unique lunar environmental phenomenon, NASA is in the process of testing the Lunar Atmosphere and Dust Environment Explorer (LADEE) in preparations for its upcoming launch. Recently, LADEE integrated the last of its three main science instruments. The three instruments to be launched with the craft are the Ultraviolet and Visible Light Spectrometer, which will analyze the light signatures of the materials it detects on the Moon, the Neutral Mass Spectrometer, set to detect differences in what little atmosphere there is on the Moon over multiple orbits, and the Lunar Dust Experiment, which will collect and analyze any dust particles that are floating around the sparse atmosphere that LADEE will be flying in.

In addition to it’s science experiments, LADEE will be technically unique in a few ways. First, it is pioneering NASA’s Modular Common Bus architecture, which will hopefully increase the compatibility between future lunar spacecraft’s communications and power systems and thereby decrease their cost.

LADEE will also carry a “technology demonstration payload,” which will allow it to communicate with Earth using lasers rather than radio waves. This will dramatically increase the speed of information transfer between the spacecraft and its controllers, resulting in almost broadband-internet levels of data exchange. If this technology proves successful it is likely to be used on future lunar exploration missions as well.

LADEE is currently undergoing a battery of environmental tests. Acoustic, vibration, shock and thermal-vacuum test still await the spacecraft after it recently passed the electromagnetic interference test. Assuming it manages to keep its clean bill of health, the spacecraft could be launched on it’s 160 day mission as early as August 2013. With its help, humanity will have a better understanding of how to combat one of the most unfriendly aspects of the lunar environment.

More information on LADEE from NASA

Posted on by Nancy Atkinson

Lunar Dust Transport Still a Mystery

Sketches made by the Apollo 17 crew of rays created by lofted lunar dust. Credit: NASA

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There are times when Moon appears to have a tenuous atmosphere of moving dust particles that are leaping up from and falling back to the Moon’s surface. First seen during the Surveyor and Apollo eras, these observations were completely unexpected, and scientists today are still trying to understand this phenomenon.

The first indication that something strange was going on with the lunar surface was in the 1960’s when cameras on the Surveyor spacecraft pointing towards the western horizon noticed a brighter hovering cloud that persisted for several hours.

“There are many other bits and pieces of observations of this kind,” said Dr. Mihaly Horanyi from the University of Colorado Boulder’s Laboratory for Atmospheric and Space Physics. “For example, the astronauts in the Apollo command modules that stayed in orbit about the Moon were hoping to take images of the dark sky, but of course there is scattered light from the dust in interplanetary space. But the brightness also appeared to follow the lunar surface, indicating that somehow dust is coming off the surface of the Moon.”

While astronauts from Apollo 8, 10, and 15 all reported such dust clouds, Apollo 17 in 1972 repeatedly saw and sketched what they called “bands,” “streamers” or “twilight rays” for about 10 seconds before lunar sunrise or lunar sunset.

Adding to the mystery, also on Apollo 17 was a dust detector placed on the surface by the astronauts, the Lunar Ejecta and Meteorite experiment, which was supposed to measure the high speed impacts of micrometeorites hitting the moon.

An Apollo 17 astronaut digs in the lunar regolith to study the mechanical behavior of moon dust. Credit: NAS

“Instead the measurements showed an increase of particle fluxes that went up a hundred fold when day turned to night and night turned into day at that location on the Moon,” Horanyi said.

“Every single one of these measurements has an alternate explanation somehow. But it seems that the whole body of these observations is best explained by recognizing that dust — even on an airless body — can move around and come to life.”

Even thought the Moon has no atmosphere, Horanyi said other processes that are likely related to the plasma and radiation environment of the Moon, “the electro-dynamic processes of the near surface lunar environment that can have strong enough electric fields and the surface can have enough electrostatic charges that can break the dust free and somehow shuffle it or move it around the surface.”

In other words, electrostatic charging of the lunar surface causes the dust to levitate, precipitated – somehow – by changes in sunlight.

Horanyi said this type of thing has been seen on other airless bodies, like on Mercury, comets and asteroids.
“For example, the near-landing on the asteroid Eros,”Horanyi said, “people noticed that the bottom of the craters are filled with fine dust, and there is not enough atmosphere, and certainly the body is too small have asteroid shakes – the asteroid version of earthquakes — so the possible transport that would trap or make dust pile up in some regions and move it from others, is most likely a plasma effect.”

Horanyi and other scientists have done lab experiments to try and replicate the lunar environment to see if a dust transport takes place.

“For the first set of experiments, imagine just a piece of surface with dust particles on it, and we shine light on this surface,” he said, “so that half is illuminated, half is not, pretending that there is a terminator region, that the sun is set on one side and is still shining light on the other. When you shine light on the surface with properties that are appropriate, you can emit photo electrons, but you only emit electrons from the lit side, and some of those electrons land on the dark side, — you have a positive charge surplus on the lit and a negative charge pile-up on the night side. Across a couple of millimeters you can easily generate a potential difference of maybe a watt, or a handful of watts, which translates actually as a small-scale, but incredibly strong electric fields. This could be like a kilowatt over a meter. But of course, it only exists over a sharp boundary, and that sharp boundary may be the key to understanding how you get dust moving to begin with.”

Horanyi said in the transient region where boundaries match up – lit and dark boundaries, or boundaries between where the surface is exposed to a plasma and where it is not – those sharp transitions could actually overcome adhesion between dust and the rest of the surface and start moving.

“And that’s where the story gets really interesting,” he said.

Hopefully, a new mission called LADEE (Lunar Atmosphere and Dust Environment Explorer) can help explain this mystery. It is slated to launch in 2013 and fly in low lunar orbit, as close to the surface as 30-50 km. Since NASA may not be sending astronaut to the Moon anytime soon, LADEE’s mission may now be a little different than previously thought, but it still has some important science to conduct.

It will carry three instruments, an infrared imager, a neutral mass spectrometer and a dust detector, which Horanyi is helping to build.

“That hopefully will be capable of measuring tiny, tiny, small particles that people argue are lofted from the surface,” Horanyis said. “And we hope that in combination these instruments might put an end to this argument that we’ve had since the early 1970’s whether dust is really actively transported and shuffled around on the lunar surface or not.”

Listen to a 365 Days of Astronomy podcast where Dr. Horanyi discusses the “Mysterious Moving Moon Dust.”