the preservation of the Apollo landing sites is important for historical and scientific reasons. The mention of "preservationists fighting to protect these historic sites" suggests that the author values the remnants of human exploration on the moon, highlighting the significance of these locations as markers of humanity's first steps beyond Earth. This indicates a belief that such sites should be maintained and respected rather than erased or altered by future lunar missions.
Apollo Astronauts
Once on the moon, Apollo astronauts had two major goals: get themselves and the moon rocks home safe. To make space on the cramped lunar modules for the hundreds of kilograms of moon samples, the astronauts had to go full Marie Kondo. Anything that wasn’t essential 5 for the ride home got tossed: cameras, hammocks, boots and trash. Downsizing also meant abandoning big stuff, like moon buggies and the descent stage that served as a launchpad for a module’s lunar liftoff. But the astronauts left more than castoffs. Starting with the Apollo 11 mission, which touched down on July 20, 1969, astronauts left six American flags and plenty of 10 personal and political mementos. Importantly, the crews also left behind instruments for about a dozen experiments to keep tabs on lunar conditions; one is still running today. These devices “were really important parts of Apollo,” says Noah Petro, project scientist for the Lunar Reconnaissance Orbiter mission. Back then, the experiments didn’t 15 get much time in the limelight, “because humans on the surface are obviously the big story,” says Petro, who is based at NASA’s Goddard Space Flight Center in Greenbelt, Md. When we think of Apollo’s 50-year legacy, most of us probably aren’t picturing the scattered remnants of astronaut outposts gathering space dust. But as nations plan new ventures to the moon, preservationists are fighting to protect these historic 20 sites so that future lunar visitors don’t erase the marks of humans’ first steps beyond Earth. Solving old mysteries By December 1972, six Apollo crews had collectively spent nearly 80 hours exploring the moon’s surface. They gathered rocks, photographed the landscape and performed all manner of experiments — from unfurling metal foil 25 to catch solar wind particles to setting off explosives and measuring the resulting seismic tremors. Apollo 11 left behind solar-powered seismometers and a reflector array that could be paired with lasers on Earth to precisely measure the distance between Earth and the moon. On five later missions, Apollo 12 through 17 (Apollo 13 returned 30 home without landing on the moon), astronauts left more elaborate setups powered by nuclear batteries that generated electricity through radioactive decay. Some of those instruments collected data through 1977, when NASA decided to focus on other projects and pulled the plug on the whole operation. “There was this period of time where the data languished,” Petro says. But within 35 the last decade or so, a new generation of scientists has taken up the torch, analyzing Apollo observations to answer questions lingering from early studies. Unfortunately, this isn’t nearly as simple as picking up where 1970s scientists left off, as geophysicist Seiichi Nagihara discovered when he set out to solve a decades-old puzzle about the moon’s underground temperature. 40 On Apollo 15 and 17, astronauts installed thermometers in the lunar surface, which took the moon’s temperature at various depths and sent the data back to Earth. When Apollo-era scientists reviewed data collected through 1974, the results revealed something odd: The moon’s temperature just beneath the surface appeared to be slowly rising. 45 “We’re talking about very minor warming,” just a couple degrees, says Nagihara, of Texas Tech University in Lubbock. But researchers at the time couldn’t figure out why. Nagihara decided to examine all the temperature data collected through 1977 to figure out what was going on. Unfortunately, the tapes that recorded these measurements were missing. This is a common problem, because during the Apollo 50 era, data were housed at the individual labs of scientists working on each experiment and many measurements were never properly archived. “A group of us decided to … try to hunt down the tapes,” Nagihara says. After scouring thousands of documents at NASA’s Johnson Space Flight Center in Houston, the researchers traced 440 tapes to an archive in Suitland, Md. But even those covered 55 only about three months of observations. At the Lunar and Planetary Institute in Houston, Nagihara and colleagues discovered more temperature measurements noted by Apollo-era scientists in weekly memos. Between the recovered tapes and the memos, Nagihara’s team pieced together a picture of the moon’s temperature from 1971 through 1977. ... 60 Computer simulations confirmed that the moon wasn’t heating up from internal processes. Astronauts trekking around the Apollo sites probably caused an increase in surface temperature of about 2 to 3 degrees Celsius, and the extra heat slowly spread more than a meter into the ground — causing the gradual warming detected by Apollo instruments. Turns out that astronaut footsteps left marks on the moon 65 far deeper than those iconic boot prints.
It can reasonably be inferred from the 5th paragraph, lines 17-21,
that the author believes
1 answer
1 answer