That's what stars do all the time.
For example, in the sun (and MOST other stars), deep down in the center
of the sun's core, two atoms of Hydrogen get squashed together so hard
that they blend into one atom of Helium AND release some energy.
That's where the sun's energy all comes from. It's called "nuclear fusion".
It needs tremendous temperature and pressure to happen. We know how
to do it, but we can't control it. So far, the only thing we've ever been able
to use it for is Hydrogen bombs.
There are 92 elements on the Periodic Table that are found in nature,
plus another 20 or so that have been made in the laboratory, but only
a few atoms of them.
The stone's altitude at time 
is given by
where 
is the acceleration due to gravity. The stone reaches the ground when 
:
Explanation:
Understanding that stars are naturally quite hot, imagine I pulled a piece of hot iron from a furnace. It would glow a bright red, and then slowly fade to black as the iron cools.
White dwarfs glow for the same reason - they are HOT!
A star is a large ball of gas that generates its own energy by fusing hydrogen atoms to make helium. It is held together by its own gravity. ... Stars come in a variety of sizes and compositions, which determine their amount of energy and gravity.
