Earth
Mars
Good question. Astronomers, believe it or not believed that venus had life since it is Earth's twin planet.
Earth is the only planet known to have life. Astronomers have found no other sign of extra terrestrial life.
It is no longer classified as a planet as astronomers now believe its a asteroid that got pulled into an orbit with our sun. Some also believe it to be a misplaced moon of Neptune.
Mars scientists found water on. Mars
Astronomers have decided that Pluto does not meet the definition of a planet.
Astronomers think Pluto is a dwarf planet. And they're right.
Astronomers believe Triton may have been a planet that was captured by Neptune because it orbits in the opposite direction of Neptune's rotation and is tilted compared to the planet's other moons. This suggests it did not form in place with the other moons of Neptune, but rather was captured later in the planet's history.
Unfortunately, no extraterrestrial life has been discovered to date, but astronomers are always on a close lookout!
pluto
No, not all astronomers consider Pluto a planet. Pluto was reclassified as a dwarf planet in 2006 by the International Astronomical Union, leading to debate among scientists about its classification. Some astronomers argue that Pluto does not meet all the criteria to be considered a full planet.
I believe there are because were not the only planet