The only trees on small bodies in our solar system are "imaginary".
Trees grow on Earth, and noplace else. I'm sure we will eventually plant some in space habitats, but that will be a while yet.
So far, we can lump the planets in our Solar System into two major groups; "terrestrial" planets that have a solid surface, and "gas giants", larger planets entirely shrouded by an atmosphere with thick clouds.
The "terrestrial" planets are Mercury, Venus, Earth and Mars; the "gas giants" are Jupiter, Saturn, Neptune and Uranus.
We don't know enough about the thousands of extra-solar planets ("exoplanets", which orbit other stars) to determine if we'll need to come up with additional categories; I think it almost certain that after we have examined a hundred or so additional planets, we'll need a dozen categories to group them.
There are many ways of dividing up the solar system into three parts.
1. The Sun.
2. Jupiter
3. Everything else
The Sun is over 99% of the mass of the entire solar system, and Jupiter is more than half of the remainder, so the other planets, all the asteroids and comets, and all of the assorted debris in the Kuiper Belt and the Oort Cloud all together is less massive than Jupiter.
Here is another possible division;
1. The Sun
2. The Earth, covered with life
3. All the other dead planets and space rocks
But this isn't particularly accurate, since while we don't know of any life elsewhere in the solar system, we cannot rule out the possibility of exotic forms of life on Mars, on Europa or on Titan - or elsewhere.
What your teacher is probably looking for is something like this;
1. The Sun
2. The Planets
3. The Asteroids and space junk.
Definition of planetoids are :-
At the present time, planets fall into four very rough categories. From large to small: 1) Gas giants, like Jupiter and Saturn; 2) Ice giants, (which are still mostly gas) like Uranus and Neptune; 3) Rocky worlds, or terrestrial planets, like Earth, Venus, Mars and Mercury; and 4) Dwarf planets, like Pluto, Ceres, Eris and Quoadar. Smaller than these, and the bodies are called "asteroids," "planetoids," "planetesimals" or "KBOs" (Kuiper Belt Objects). Bigger, and they become "Planetars," "Brown dwarfs" or "PMOs" (Planetary Mass Objects). Bigger still, and they become stars.
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Until about 2006, there was no formal definition of a "planet". But faced with the discovery of several objects out in the Kuiper Belt beyond the orbit of Neptune, and the near certainty that more such objects would be found as our telescopes improved, the International Astronomical Union (IAU) proposed three criteria that any planet must meet.
1. A planet must orbit a sun.
2. A planet must have reached hydrostatic equilibrium; in other words, its mass is great enough that its own internal gravity has crushed it into a spherical shape.
3. A planet must have cleared its orbit of other objects, meaning that there are no other objects in similar orbits. For example, the asteroid Ceres is not a planet even though it meets the first two criteria, because there are thousands of other objects in the same general orbital area.
Objects like Ceres and Pluto which meet the first two criteria but not the third are called "dwarf planets".
Please note that astronomers are still divided on some of these issues, and the definition of "planet" may be modified by later meetings of the IAU.
They classify Galaxy's by their shape, size, composition & color.
the three types of celestial bodies in the solar system are stars,comets and planets
A planet has to be a large object that:
1. orbits a star,
2. is sphere-shaped ,
3. clears the neighborhood around its orbit.
Scientists classify galaxies by their shape.
To compare and classify stars.
Astronomers.
Astronomers
One way to categorize the solar system's planets?
The planets are normally classified in size by their equatorial diameter.
Teams of astronomers have studies all possible planets.
Astronomers use a telescope to view planets directly.
Astronomers classify stars.
Many astronomers, historians, regular people, and scientisis know about the planets in our Solar system.
astronomers
To compare and classify stars.
before the teloscope was invented what were ancient astronomers able to learn about the planets ?
Because the ancient Greek astronomers were one of the first astronomers to discover the planets. As they looked at the planets over time they moved into different places. The planets seemed o orbit the Sun so the Greek astronomers called them planets, which meant :wanderers.
a lot
Astronomers.
Astronomers.
Astronomers (and their ilk) study stars and planets.