Are there objects in our solar system that aren’t planets? How would you categorize these objects?

Answer: The solar system comprises of a central yellow dwarf star that is called the sun with several planetary bodies that are revolving around it on constant basis and motion. However, other than the sun and the planets revolving around the sun, there are also numerous other objects in the solar system (Batygin & Brown, 2016). These objects include planetary satellites, asteroids, meteors, meteorites, comets, dust particles and others. These objects can be categorized as explained as follows.

Planetary Satellites – These objects are almost similar in appearance with the planets except they are much smaller than the planets and they revolve around the planets similar to the motion of the planets around the sun. Mercury and Venus are confirmed to have no satellites, Earth has one, Mars has two and the giant planets have many. For the giant planets, the satellites do not have much effect on the climate and conditions inside the planet but for the smaller terrestrial planets (Earth and Mars), the satellites play major role (Way et al., 2016). For example, the Earth’s satellite the Moon helps in controlling the tide cycle on the Earth by the force of gravity. Some satellites of the giant planets like Titan (Saturn) and Europa (Jupiter) are considered to have possible conditions for terraforming and developing future human habitability. For the planet Saturn, it is assumed that the rings of the planet have been caused by the destruction of one or more of its satellites and the debris that are now revolving around Saturn.

Asteroids – Asteroids are solid objects that revolve around the sun but unlike the planets or satellites, they do not have any distinct round shapes and are much smaller in size. There are two known asteroid belts in which there are thousands of asteroids within the same orbit. The first asteroid belt lies between the orbit of Mars and Jupiter and the other asteroid belt, namely the Kuiper Belt that lies beyond the orbit of Pluto.

Comets – Comets are icy astronomic bodies that revolve round the sun at much faster pace than the planets but have no distinct orbits. When the comets come near the sun, the icy body releases vapor and gases resulting in the formation of a “tail” (Morbidelli et al., 2015). The visibility of the comets from the earth depends on the brightness of the tail. The orbits of the comets are much different from the planets and are also irregular unlike the planets.

Meteors – Meteors are small rocky bodies that randomly wander in the solar system. Often these bodies enter into the Earth’s atmosphere and get ignited by the atmosphere’s friction. Other meteors crash on the bodies of the planets and the satellites (Mamajek et al., 2015). The craters on the Moon are caused by various large sized meteors that have crashed on the surface due to lack of atmosphere on the satellite.

Stellar Dusts and Debris – Stellar dusts and debris are created by various processes and occupy a significant empty space in the solar system.

References

Batygin, K., & Brown, M. E. (2016). Evidence for a distant giant planet in the solar system. The Astronomical Journal, 151(2), 22.

Mamajek, E. E., Barenfeld, S. A., Ivanov, V. D., Kniazev, A. Y., Väisänen, P., Beletsky, Y., & Boffin, H. M. (2015). The closest known flyby of a star to the Solar System. The Astrophysical Journal Letters, 800(1), L17.

Morbidelli, A., Lambrechts, M., Jacobson, S., & Bitsch, B. (2015). The great dichotomy of the Solar System: Small terrestrial embryos and massive giant planet cores. Icarus, 258, 418-429.

Way, M. J., Del Genio, A. D., Kiang, N. Y., Sohl, L. E., Grinspoon, D. H., Aleinov, I., … & Clune, T. (2016). Was Venus the first habitable world of our solar system?. Geophysical research letters, 43(16), 8376-8383.