Without a doubt there are more scientists observing Earth than any other planet.
However, "externally" I would say it would be Mars after The Moon.
Most of the NASA planets fall in the world, although a few of them haven't, whereas relatively few non-NASA planets fall in the world.
Some of the things NASA (National Aeronautics and Space Administration) has done is taught humans about things far beyond our planet earth and lead most trips to the moon.
No. In fact most jobs at NASA would be scientists, engineers, accountants, architects, and administrators ranging across a number of disciplines. Flying would be a very small and highly competitive part of NASA's program.
some scientists say yes others no but most say no
More than half
People have known about Mars since ancient times. Indeed, its name comes to us from the ancient Romans who associated it with their god of war (Mars) because of the planet's red color. Nasa probably found out about mars from going to school. Most of the people who were hired at NASA back in its early years had to be pretty smart, so most of them probably came from good schools. On the other hand, thanks in part to Percival Lowell, the idea that some form of civilization existed on Mars was wide spread during the early 20th century, and it fueled the literary Genera known as "Science Fiction." It is possible that many NASA scientists knew about Mars even before they went to school by reading about it in Science fiction and Fantasy magazines.
NASA? A2. I'd expect the place with the largest concentration of scientists would be the universities. From undergraduate, right through to professors emeritus.
Not yet, at least. NASA is looking, as well as most other space programs around the world.
Hydrogen is the most commonly observed element in the universe and is likely contained in every planet.
NASA's Cassini spacecraft has moved on to the next stage of its Saturn mission, which will allow scientists to study seasons and other long-term weather phenomena on the ringed planet and its moons.
Technically speaking... Neptune. It was pluto, but scientists considered it no longer a planet.
Mars