Universe Today

The uses for duct tape seem to be endless. From the Apollo missions in the 1970’s to the International Space Station today, duct tape has been used as quick fixes and semi-permanent solutions to a variety of tasks. In a story released today from NASA documenting the events of the Apollo 17 in 1972, duct tape became the saviour of astronauts Gene Cernan and Jack Schmitt as they sped around on the lunar surface in their moonbuggy. Damage to the buggy’s wheel arch could have put the pair at risk and may have curtailed the surface mission (pictured). But with a flash of inspiration and “can do” attitude Cernan and Schmitt found the answer in a roll of grey sticky tape…

It would seem duct tape holds the world together as it is, and it is becoming clear that the tape may hold the frontier of space together too. I recently came across the NASA Astronomy Picture of the Day with a view from the ISS looking over Rick Linnehan as he carried out an EVA during the STS-123 mission in March. As many blogs commented, “wow, even the space station is held together with duct tape!“, duct tape and Velcro did indeed appear to be the best way for astronauts to attach things, fix things and cover up things. In the Great Moonbuggy Race in Huntsville, Alabama, Prof. Paul Shiue of Christian Brothers University even joked that duct tape was his team’s “best engineering tool”. It seems the space station crew agrees with Prof. Shiue as is evident in the photo below.

I think people are surprised that such a common, everyday tool can be utilized in space too, but I’d argue that this kind of versatile and strong tape should be in space doing its bit for space exploration. It seems NASA thinks the same thing. Back in 1972, the use of duct tape turned a potentially dangerous situation into mission success for the Apollo 17 astronauts.

During Gene Cernan and Jack Schmitt’s Moon walk, they employed the use of a moonbuggy to get around the dusty terrain. As is becoming abundantly clear, Moon dust will be one of the biggest challenges to mankind’s efforts on the Earth’s only natural satellite. For starters, this fine Moon “regolith” (dust formed from pulverized rock after countless meteorite impacts) will get everywhere. It is so fine that that it will likely obscure vision and could cause a host of respiratory problems. But the critical issue facing the Apollo astronauts was the dark Moon dust getting stuck to their spacesuits. The moonbuggy was designed to suppress the dust from being kicked up from the surface and spayed over the passengers. Should the spacesuits have a layer of dust over the top, solar electromagnetic radiation would be absorbed very efficiently, causing the astronauts to overheat. At all costs, spacesuits and equipment would need to be “dusted off” to prevent any problems.

Within two hours of the Lunar lander Challenger landing on December 11th, 1972 (at 02:23:35 UTC), Cernan and Schmitt were busy loading the moonbuggy with geology tools and experiments. In a seemingly minor error, the hammer strapped to Cernan’s suited leg caught the buggy’s rear fender and ripped it half off. It may not sound like much; after all who needs a fender on the Moon? But this was a big problem. If they were to use the buggy in this condition, huge plumes of dust would be kicked up (known as “rooster tails”) and showered over the astronauts, sticking to their suits, possibly causing serious overheating issues. Lunar dust is also very abrasive and static, should it get wiped off visors, the glass will get scratched, impeding vision. Joints, latches and hinges would also get severely damaged by the stuff.

Fortunately the astronauts had packed duct tape and were able to do a make-shift job at fixing the fender. Unfortunately the harsh vacuum of space, the continuous exposure to the Sun and the ever present dust caused the tape to lose its “stick”. A more permanent solution was required. After communication with mission control, a solution was found. Using a combination of duct tape and laminated maps, the fender could be reconstructed. The EVA continued and the mission was a success.

See the NASA video of Gene Cernan carrying out duct tape repairs on the Moon »

The Apollo 17 mission is the last time man walked on the Moon, and remains the most extreme place where duct tape was called into use.

For the complete and absorbing story about the duct tape repair job by Gene Cernan, check out the full NASA article…

It happens every month and specifically every time the moon is full. According to scientists, for about three days on both sides of a full moon, the lunar surface could transform from a tranquil, inert landscape to an electrically charged, potentially dangerous environment. During this time, the moon ploughs through Earth’s magnetic “tail” — an extension of Earth’s magnetic field. Out in space, the solar wind stretches out the magnetic bubble that surrounds our planet, creating a long “magnetotail” in the downwind direction. When the moon comes in contact with this field, it could cause lunar dust storms and discharges of static electricity. Future lunar explorers might possibly have to take extra precautions during that time of the month.

“Earth’s magnetotail extends well beyond the orbit of the Moon and, once a month, the Moon orbits through it,” said scientist Tim Stubbs from the Goddard Space Flight Center. “This can have consequences ranging from lunar ‘dust storms’ to electrostatic discharges.”

When the moon crosses this magnetotail, it comes in contact with a gigantic “plasma sheet” of hot charged particles trapped in the tail. The lightest and most mobile of these particles, electrons, pepper the Moon’s surface and give the Moon a negative charge.

Scientists say that on the Moon’s dayside this effect is neutralized somewhat by sunlight. The ultraviolet photons knock electrons back off the surface, keeping the build-up of charge at relatively low levels. But on the nightside of the Moon, where it’s cold and dark, electrons accumulate and voltages can climb to hundreds or thousands of volts.

Stubbs said that astronauts walking across the dusty charged-up lunar terrain may find themselves crackling with electricity like “a sock pulled out of a hot dryer.” Touching another astronaut, a doorknob, a piece of sensitive electronics—any of these simple actions could produce an unwelcome zap. “Proper grounding is strongly recommended,” Stubbs said.

Moon dust could become charged enough to actually lift from the surface. There’s evidence from the Surveyor 7 lunar lander that when sufficiently charged-up, lunar dust particles could actually float above the lunar surface. This dust could cause problems as it clings to spacesuits, clogs machinery, scratches helmet faceplates (moondust is very abrasive) and generally make life difficult for astronauts.

Much of this is pure speculation, however, Stubbs said, as no one has been on the moon during this time. “Apollo astronauts never landed on a full Moon and they never experienced the magnetotail.”

The best direct evidence of this event comes from NASA’s Lunar Prospector spacecraft, which orbited the Moon in 1998-99 and monitored many magnetotail crossings. During some crossings, the spacecraft sensed big changes in the lunar nightside voltage, jumping from -200 V to -1000 V, according to Jasper Halekas of UC Berkeley who has been studying the data.

Scientists also say this phenomenon would be worse during a solar storm.

More research will have to be done regarding this monthly cycle and how it might affect those living on the moon in the future.

Original News Source: Science @ NASA