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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
- 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
- StarChild: Glossary - NASA
BLACK HOLE An invisible object in outer space formed when a massive star collapses from its own gravity A black hole has such a strong pull of gravity that not even light can escape from it BLUR To make less clear, to run together BIG BANG THEORY A theory that says the universe began with a super-powerful explosion BOLT A flash of lightning
- Getting at Groundwater with Gravity - NASA Earthdata
NASA’s twin Gravity Recovery and Climate Experiment (GRACE) satellites can detect groundwater by measuring subtle variations in Earth’s gravity This image shows the world’s average annual cycle of water storage on land, computed from four years of GRACE gravity data Colors indicate how much groundwater comes and goes, each year, in various regions; red indicates high levels of annual
- 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
- Glacier Power: How do Glaciers Move? | NASA Earthdata
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 it creeps down the valley
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