Spacecraft
A spacecraft is a vehicle or machine designed to fly in outer space, either crewed or uncrewed, used for purposes such as exploration, communications, weather monitoring, scientific research, or transportation. Spacecraft are propelled initially by rockets to escape Earth's gravity and then use the vacuum of space with minimal fuel, relying on orbital mechanics, gravitational assists, and onboard thrusters for navigation. They range from small CubeSats in low Earth orbit to interstellar probes like Voyager 1, which has travelled beyond the heliopause into interstellar space.
Notable Solar System exploration spacecraft
| Spacecraft | Agency | Launch Year | Destination | Notable Achievement |
|---|---|---|---|---|
| Voyager 1 | NASA | 1977 | Outer planets / Interstellar | First human object in interstellar space |
| Cassini–Huygens | NASA/ESA | 1997 | Saturn system | Orbited Saturn 13 years; landed on Titan |
| New Horizons | NASA | 2006 | Pluto / Kuiper Belt | First close flyby of Pluto (2015) |
| Mars Perseverance | NASA | 2020 | Mars | First powered flight on another planet |
| ISRO Chandrayaan-3 | ISRO | 2023 | Moon | First soft landing near lunar south pole |
Interactive Tools
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Related Terms
Solar Wind
Solar wind is a continuous stream of charged particles — primarily electrons and protons — that flows outward from the Sun's corona in all directions at speeds of 400–800 km/s. This plasma flow carries the Sun's magnetic field into interplanetary space, forming the heliosphere, and interacts with planetary magnetospheres to produce phenomena such as aurorae and geomagnetic storms. Solar wind intensity varies with solar activity, and during coronal mass ejections it can temporarily intensify to disrupt satellite communications, power grids, and GPS systems on Earth.
Gravitational Force (Astronomy)
Gravitational force in astronomy is the attractive force between any two masses, governed by Newton's Law of Universal Gravitation, which states that the force is proportional to the product of the masses and inversely proportional to the square of the distance between them. This force is responsible for holding planets in orbit around the Sun, governing the motion of moons, shaping the structure of galaxies, and dictating the trajectories of spacecraft. It is the dominant long-range force at astronomical scales and underlies phenomena from tidal locking to the formation of planetary systems.
Kepler's Third Law
Kepler's Third Law states that the square of the orbital period of a planet is proportional to the cube of the semi-major axis of its orbit around the Sun. This relationship, discovered by Johannes Kepler in 1619, applies to all objects orbiting the same central body and allows astronomers to calculate orbital periods or distances when one is known. It was later explained theoretically by Newton's law of universal gravitation and remains a foundational tool for planetary science and space mission planning.
Compound of "space" (from Latin spatium, "room, expanse") and "craft" (from Old English cræft, "skill, trade, vehicle"). The word came into common use during the Space Age, beginning in the late 1950s with the launch of Sputnik 1 in 1957.