National Mall
Exploring the Planets
15 reading stories
Enter the experience →Blink Comparator
A blink comparator switches quickly between two photographs of the same stars taken on different nights. Distant stars stay still, but a nearer moving world appears to jump. Clyde Tombaugh used one like this to discover Pluto in 1930.
Read the story →Kepler Technology Demonstrator
Kepler searched for tiny, repeated dips in starlight when a planet crossed in front of its star. This apparatus helped prove that the detector could measure changes that small from space. A transit may dim a star by only a tiny fraction. Kepler needed stable pointing, sensitive detectors, repeated observations, and methods for rejecting changes caused by the star or the instrument itself.
Read the story →Mariner 10
Mariner 10 flew past Venus so the planet’s gravity could bend the spacecraft’s path toward Mercury. It became the first spacecraft to visit two planets. A gravity assist trades energy and direction between a spacecraft and a moving planet. Mariner 10’s Venus encounter made repeated Mercury flybys possible while thermal design protected its systems from intense sunlight.
Read the story →Mariner 9 Globe of Mars
Mariner 9 orbited Mars and sent more than 7,000 images covering most of the planet. Joined into a globe, those images revealed huge volcanoes and a canyon system that telescopes had not shown clearly. Mariner 9’s images covered about 85 percent of Mars. Creating a globe required matching scale, position, lighting, and overlap while recognizing that gaps and uneven resolution still shape the result.
Read the story →Mars Exploration Rover
This test rover let engineers try commands on Earth before sending them to Spirit or Opportunity. The Mars rovers acted like field geologists, examining rocks and finding evidence that water once affected their landing sites.
Read the story →Mars Meteorite
An impact blasted this rock away from Mars. Long afterward it fell in Antarctica, where scientists compared gases trapped inside it with measurements made by Viking landers. The meteorite’s relatively young age indicated formation on a large, geologically active body. Trapped gases closely matched the Martian atmosphere measured by Viking, and impact processes could explain its launch and eventual fall to Earth.
Read the story →Mars Pathfinder Rover Marie Curie
Sojourner was the first rover to operate successfully on Mars. This flight spare, Marie Curie, shows the compact robot that tested mobility, cameras, and rock measurements for later missions. Pathfinder combined an airbag landing, a stationary lander, and a solar-powered rover weighing about 11.5 kilograms. Sojourner’s short drives tested how a mobile robot could negotiate terrain and place an instrument against rocks.
Read the story →Mars Science Laboratory Curiosity
Curiosity carries cameras, a robotic arm, and instruments for studying rocks as it climbs through layers in Gale crater. A hovering sky crane lowered the one-ton rover to the surface. Curiosity reads changing rock layers as a record of past environments. Its nuclear power source, rocker-bogie suspension, remote-sensing tools, and contact instruments allow the team to choose targets and test whether ancient settings could have supported microbial life.
Read the story →Searching for Goldilocks
Angela Palmer’s glass sculpture turns distant planetary systems into a three-dimensional star map. The bright marks identify stars with planets orbiting in a region where liquid water might be possible. Each glass plate represents another 250 light-years of distance. The sculpture compresses a vast volume of space into a form we can compare, while the term “Goldilocks zone” describes orbital temperature conditions rather than a complete test for life.
Read the story →Stardust Capsule
Stardust collected tiny particles in very light aerogel, then sealed them inside a capsule that survived a fiery return through Earth’s atmosphere. Scientists could study the actual material instead of observing it only from far away.
Read the story →Surveyor 3 Camera
Surveyor 3 used this kind of television camera on the Moon in 1967. Apollo 12 astronauts reached the lander 31 months later and returned the camera so engineers could study what the lunar environment had done to it.
Read the story →Viking Lander Camera
The Viking camera scanned a narrow vertical strip, rotated slightly, and scanned again. Many strips stacked together became a panorama of the Martian surface. A line-scan image depends on the camera’s rotation, the order of the scans, detector response, and stable geometry. A problem in any one strip can appear as a band or distortion in the assembled picture.
Read the story →Viking Life Science Experiment
Viking carried instruments that measured the atmosphere and tested the chemistry of soil. The experiments looked for patterns that life might produce, but scientists had to consider nonliving chemistry too. Viking’s experiments exposed Martian material to carefully designed conditions and measured gases and organic chemistry. Interpreting the results required comparison tests and competing explanations for reactive soil.
Read the story →Voyager Record Cover
Each Voyager carried sounds and images from Earth. The cover uses pictures, patterns, and physical measurements to suggest how the record should be played—even if the finder knows no human language. Its diagrams use physical phenomena—hydrogen, time intervals, signal structure, and pulsar locations—as a possible common language. Every symbol still assumes that a receiver can recognize the pattern and infer its purpose.
Read the story →Voyager Spacecraft
Voyagers 1 and 2 carried cameras and other instruments past the giant planets. Their large dish antennas sent discoveries across billions of kilometers, and their power systems kept working far from sunlight. The Voyagers had to gather data, survive radiation and cold, control their orientation, produce power, and communicate across enormous distances. Their planetary encounters used carefully timed flight paths rather than engines powerful enough to stop at every world.
Read the story →