Planets
Mars
Mars is a cold desert world whose surface preserves evidence of ancient water, volcanic history, impact basins, and active rover exploration.
Thin carbon dioxide atmosphere
Two moons: Phobos and Deimos
Day length is about 24.6 hours
Spacepedia
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Space concepts, missions, and sources in one field guide.
Start with a curated NASA-backed article, then ask COSMOS for a beginner, student, or researcher explanation.
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Planets
Jupiter
Jupiter is the largest planet in the Solar System, a gas giant with powerful storms, strong radiation belts, and a complex moon system.
Great Red Spot storm system
Fast day under 10 hours
Explored closely by NASA's Juno mission
Stars
The Sun
The Sun is a G-type main-sequence star whose magnetic activity shapes space weather across the Solar System.
Primary energy source for Earth
Solar flares and CMEs affect space weather
Studied by missions including Parker Solar Probe
Black Holes
Black Holes
Black holes are regions where gravity is so strong that light cannot escape from inside the event horizon.
Can form from collapsed massive stars
Supermassive black holes sit in many galaxy centers
Detected through effects on matter and light
Galaxies
The Milky Way
The Milky Way is our home galaxy: a barred spiral galaxy containing stars, gas, dust, dark matter, and the Solar System.
Contains hundreds of billions of stars
The Solar System orbits far from the galactic center
Its center hosts a supermassive black hole
Space Missions
Apollo 11
Apollo 11 was the first mission to land humans on the Moon, turning lunar exploration into a defining scientific and cultural milestone.
Landed in 1969
Crew: Neil Armstrong, Buzz Aldrin, Michael Collins
Returned lunar samples to Earth
Space Missions
James Webb Space Telescope
JWST is NASA's infrared flagship observatory, built to study early galaxies, star formation, exoplanets, and distant cosmic structure.
Observes primarily in infrared
Operates near Sun-Earth L2
Uses a segmented golden mirror
Astronauts
Astronaut Training
Astronauts train for spacecraft systems, robotics, science operations, spacewalks, teamwork, and emergency procedures.
Training can include simulators and underwater spacewalk practice
Crew roles span piloting, science, engineering, and medicine
ISS missions require international coordination
Cosmology
Big Bang Cosmology
Big Bang cosmology describes the universe expanding from an early hot, dense state into the structured cosmos observed today.
Supported by cosmic expansion
Cosmic microwave background is key evidence
Galaxy surveys map large-scale structure