is an attractive force that draws masses to each other.
We are a small mass compared to the earth. Why do you fall back on the
earth after you jump? Well, the smaller mass is always attracted more
to the larger mass, this means we (the smaller mass) are attracted to
the earth (the larger mass). The larger the mass, the more we are attracted
Do astronauts on the moon feel gravity ?
Gravity is everywhere because it acts between and among all different
masses! Gravity's range is infinite it reaches everywhere. Therefore,
astronauts do get affected by gravity on the moon, the earth, and everything
in the universe!
On Jupiter (a very massive planet) you weigh a lot, but on the moon
(which is a small mass compared to Jupiter or Earth) you weigh a lot
less! And on Earth (a mass in-between Jupiter and the moon) you weigh
normal. (Distance is also a factor in gravity. If you are far away from
a mass, then it's gravity doesn't affect you as much as when you are
on top of the mass. For example, you don’t feel Jupiter’s
gravity very much on Earth, but when we actually go to Jupiter, you
will feel extremely heavy.
If the object you are standing on magically increases its mass, your
weight will increase. That is, more massive planets have a larger gravitational
force! This means that astronauts can do lots of different things on
the moon than on the earth because the gravity is not as strong on the
moon as it is on Earth. The moon is not as massive as the earth.
Gravity and why does it happen ?
Isaac Newton discovered gravity. He said that gravity is the force that
attracts masses to one another. Since then, the idea of gravity has
progressed. There is a hypothesis that states that the attraction between
masses (gravity) exists through the exchange of gravitons.
what are gravitons ?
Gravitons are particles that every mass gives off. Gravitons are very
interesting particles because they have no mass! Gravitons are exchanged
between everything this means you are exchanging gravitons with the
sun and even your friends! Because gravitons have no mass, no one can
can act on light too. It has been observed in nature that the path of
light can be bent in vacuum if the light rays are near a very massive
object called a black hole. A black hole has such a strong gravitational
attraction that some scientists speculate that the whole universe revolves
around a large black hole.
Black hole is special because their gravitational attraction even draws
light in from nearby stars!
How can the direction of light be changed ?
Light is also made of a hypothetical particle called a photon. Photons
are a lot like gravitons, they have no mass. The black hole distorts
space and time thereby capturing the photons passing next to it. The
distorted space looks sort of like the vortex twister you see when bathtub
water drains from the tub. At the end (the tip) of the vortex is where
you would find the black hole itself. Similar to a soap bubble following
the vortex path of the water in the bathtub drain, the photon must follow
the distorted path of space generated by the black hole.