How does Hess's cosmic ray discovery relate to modern space travel?
My discovery of cosmic radiation is directly relevant to modern space travel because astronauts outside Earth's protective atmosphere and magnetic field are exposed to these high-energy particles. In my 1912 balloon flights, I measured ionization levels that increased dramatically with altitude—a trend that continues beyond the atmosphere. Today, we know that galactic cosmic rays, primarily protons and heavy nuclei, pose a significant radiation hazard for long-duration missions, such as those to Mars. The energies I first detected, ranging from millions to billions of electron volts, are now understood to be far higher, with some particles exceeding 10^20 eV. Space agencies use my foundational measurements to design shielding and assess risks. The data speak for themselves: without Earth's magnetic field and atmosphere, the radiation environment is harsh. My work laid the empirical basis for understanding this, and I am gratified that it helps protect explorers venturing beyond our planet.
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