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View of the Steven F. Udvar-Hazy Center tower at sunset

One museum, two locations

Visit us in Washington, DC and Chantilly, VA to explore hundreds of the world’s most significant objects in aviation and space history. Free timed-entry passes are required for the Museum in DC.

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Apollo 11: Buzz Aldrin on the Moon

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space shuttle launch

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Women in Aviation and Space Family Day

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Bob Hoover Gives an Air Show Performance

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Illustration of MARSIS Radar Sounder Instrument

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  3. Illustration of MARSIS Radar Sounder Instrument
  • Artist concept of the MARSIS Radar Sounder Instrument, a part of a spacecraft orbiting Mars, as it uses radio waves to penetrate certain materials and reflect back to the spacecraft when a change in density or composition is made. Upward arrows are used to label subsurface features while downward arrows label the surface reflection of the radio waves.
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    The MARSIS radar sounder instrument on the European Space Agency’s Mars Express spacecraft is comprised of a 40 meter (about 131 feet) dipole antenna. MARSIS transmits long wavelength, low frequency radio waves that can penetrate certain geologic materials and are reflected back where the radio waves encounter a change in bulk density or composition. The radargram, a time delay rendering of the reflected radar pulses, shows a subsurface feature or reflector (upper pointing arrows) separated from the surface reflection (downward pointing arrows) in Meridiani Planum. The subsurface reflector is interpreted to be the base the Meridiani Planum deposits, about 1 kilometer (about 0.62 miles) beneath the surface.   

  • Artist concept of the MARSIS Radar Sounder Instrument, a part of a spacecraft orbiting Mars, as it uses radio waves to penetrate certain materials and reflect back to the spacecraft when a change in density or composition is made. Upward arrows are used to label subsurface features while downward arrows label the surface reflection of the radio waves.

Credit:

<p>ESA/NASA/JPL/KU/Smithsonian</p>

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National Air and Space Museum

6th St. and Independence Ave SW
Washington, DC 20560

202-633-2214

Open daily
10:00 am - 5:30 pm
Free Timed-Entry Passes
Required

Steven F. Udvar-Hazy Center

14390 Air and Space Museum Parkway
Chantilly, VA 20151

703-572-4118

Open daily
10:00 am - 5:30 pm
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