Planet Compare - NASA Solar System Exploration
2024年12月19日 · Explore NASA's real-time science encyclopedia and compare the sizes of planets in our solar system.
In Depth | Our Solar System – NASA Solar System Exploration
Our solar system consists of our star, the Sun, and everything bound to it by gravity – the planets Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, and Neptune; dwarf planets such as Pluto; dozens of moons; and millions of asteroids, comets, and meteoroids.
What is a Planet? | Planets – NASA Solar System Exploration
Everyone knows that Earth, Mars and Jupiter are planets. But both Pluto and Ceres were once considered planets until new discoveries triggered scientific debate about how to best describe them—a vigorous debate that continues to this day.
In Depth | Moons – NASA Solar System Exploration
Of the terrestrial (rocky) planets of the inner solar system, neither Mercury nor Venus have any moons at all, Earth has one and Mars has its two small moons. In the outer solar system, the gas giants Jupiter and Saturn and the ice giants Uranus and Neptune have dozens of moons.
In Depth | Earth – NASA Solar System Exploration
Our home planet is the third planet from the Sun, and the only place we know of so far that’s inhabited by living things. While Earth is only the fifth largest planet in the solar system, it is the only world in our solar system with liquid water on the surface.
The Solar System and Beyond is Awash in Water
2015年4月6日 · Earth isn't the only ocean world in our solar system. Oceans could exist in diverse forms on moons and dwarf planets, offering clues in the quest to discover life beyond our home planet. This illustration depicts the best known candidates in …
Gravity Assist: Ice Giants (Uranus & Neptune) with Amy Simon
2018年1月17日 · They're very different planets than the other ones we think of. And part of the reason we call them ice giants is because they actually have a lot of water ice. So, while some of the other gas giant planets are mostly hydrogen and …
theory about the beginnings of the sun and planets. This theory explains that our solar system began as a spinning cloud of gas and dust about 4.5 billion years ago.
Rise and Shine with the Planets - NASA Solar System Exploration
2006年8月15日 · The planets Venus, Mercury and Saturn dance on the ecliptic -- the plane of Earth's orbit and the imaginary line tracing it in the sky. The sun, moon and planets appear to move along this line. Venus, rising an hour and a half …
Asteroids, Comets & Meteors - NASA Solar System Exploration
Don’t let the name fool you. Our solar system’s small bodies – asteroids, comets, and meteors – pack big surprises. These chunks of rock, ice, and metal are leftovers from the formation of our solar system 4.6 billion years ago.