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- What is gravity? - NASA
Newton's "law" of gravity is a mathematical description of the way bodies are observed to attract one another, based on many scientific experiments and observations The gravitational equation says that the force of gravity is proportional to the product of the two masses (m 1 and m 2), and inversely proportional to the square of the distance (r) between their centers of mass Mathematically
- Matter in Motion: Earths Changing Gravity | NASA Earthdata
A new satellite mission sheds light on Earth's gravity field and provides clues about changing sea levels
- Gravity Gravitational Field - NASA Earthdata
Gravity is the field around physical bodies, such as planets, that draws objects toward its center Earth's gravitational field can be measured by orbiting satellites that can detect changes to it These variations are related to change or transportation of mass, which can provide information on ocean circulation, glacial melt, droughts, or geodesy
- StarChild: Glossary - NASA
GRAVITATIONAL PULL See Gravity GRAVITY The force of attraction between two objects which is influenced by the mass of the two objects and the distance between the two objects GYROSCOPE A heavy wheel or disk mounted so that its axis can turn freely in one or more directions A spinning gyroscope tends to resist change in the direction of its axis
- Glacier Power: How do Glaciers Move? - NASA Earthdata
Glaciers Are Solid Rivers A glacier is a large accumulation of many years of snow, transformed into ice This solid crystalline material deforms (changes) and moves Glaciers, also known as “rivers of ice,” actually flow Gravity is the cause of glacier motion; the ice slowly flows and deforms (changes) in response to gravity A glacier molds itself to the land and also molds the land as
- StarChild: Stars - NASA
Gravity causes the last of the star's matter to collapse inward and compact This is the white dwarf stage which is extremely dense White dwarfs shine with a white hot light but once all of their energy is gone, they die The star has now reached the black dwarf phase
- How do we know that dark matter exists? - NASA
The cluster does not behave as scientists would expect it to if only the visible matter is generating the gravity present in the cluster 'Dark matter' theory suggests that a huge amount of dark (invisible to direct observation) matter, interacting gravitationally with the normal, visible matter in the universe, exists
- StarChild: Galaxies - NASA
A galaxy is a cluster of stars, dust, and gas which is held together by gravity Galaxies are scattered throughout the universe and they vary greatly in size A galaxy may be alone or it may be in a large group of galaxies called a "supercluster" Galaxies are classified by scientists according to their shape and appearance An irregular galaxy has an undefined shape and is full of young stars
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