Chapter 7 of 10

Rolling Up a Piece of the Sun

Stowing the Solar Wind Composition (SWC) foil after 77 minutes of exposure (GET 111:20:11)

Told in Eagle’s imagined voice · the events are real · source

One month after its first image of the Apollo 11 landing site was acquired, NASA Lunar Reconnaissance Orbiter passed over the site again providing a new view of the historic site.
EagleYou cannot catch the Sun's wind on Earth—our planet's magnetic shield deflects it—so Buzz planted a shiny metal banner in the dirt near me.
NASA/GSFC/Arizona State University
01It wasn't a flag. It was a four-foot-long sheet of ultra-pure Swiss aluminum foil hung on a telescoping pole, facing directly into the blazing sunlight.
For exacty seventy-seven minutes, an invisible storm of atoms blown off the Sun slammed into that foil at a million miles per hour.
02With no lunar atmosphere to slow them down, particles of solar helium, neon, and argon buried themselves straight into the microscopic metal layers of the sheet.
Personnel atop the 402-ft.
EagleRight before climbing back up my ladder, Buzz rolled the foil up like a window shade and sealed it inside the heavy metal rock box.
NASA/JSC
03Unlike the laser mirror or the seismometer, this instrument had zero sensors of its own—the foil itself had to fly back to laboratories on Earth to be melted and analyzed.
The foil rode home inside my cabin, while its empty metal pole was tossed into the lunar dust beside me.
04That empty staff still lies at Tranquility Base today, while the atoms trapped in its foil revealed the exact chemical recipe of our Sun.

The big idea

Because the Moon lacks an atmosphere or global magnetic field, raw particles streaming from the Sun hit the lunar surface directly—allowing a simple sheet of aluminum foil to trap physical samples of the Sun.

Think about it

Why did scientists have to unroll this aluminum foil on the Moon instead of just holding it up on a high mountain on Earth?

In this chapter: Ultra-pure aluminum collector foil and a 5-foot telescoping metal pole

Sources: Main record · NASA · How the solar-wind collector worked

Machine illustration: AI-made. Photos: NASA Image and Video Library, credited on each picture.

Chapter 7 of 10

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