THEMUSEUM Family Exhibitions: Discovering Pluto
This is the first in an ongoing series for THEMUSEUM’s Summer of Discovery exhibition. From now until Labour Day come discover the worlds of magic and fantasy, space, science, interactive art and more! Previously: Transcending the Physical Boundaries of Theater
This summer you can come discover space with our Mission: Outer Space exhibition and by watching one of our famous Star Lab Star Shows; immerse yourself in galaxies near and far, discover stars, visit planets and learn about our universe’s billions of years of history!
Many people are aware that we live on the planet Earth, which orbits around our solar system’s one and only star: the Sun. Our solar system is located in the Milky Way galaxy, which is believed to hold millions, or even billions, of other stars with their own unique solar systems and planetary systems (who knows what else could be beyond the horizon?!).
Our solar system contains eight planets: Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus and Neptune. However, many of our staff often debate this number with our younger visitors. Everyone who learned about our solar system before 2006 was taught that we belong to a system of nine planets, with Pluto coming in last. Now, however, many young students have never even heard of Pluto and are surprised to learn that it was once considered a planet.
So, what caused this rift? And why are so many older generations still pining for the return of Pluto? The explanation is still considered to be controversial by many, and can cause a swell of emotions when being discussed.
In 2006, Pluto was demoted from planet status to that of a dwarf planet thanks to an official vote by the International Astronomical Union (IAU), a move that still stabs the hearts of many.
Now, what is the different between a planet (such as Earth) and a dwarf planet?
According to the IAU, a planet must meet the following requirements:
A celestial body that (a) is in orbit around the Sun, (b) has sufficient mass for its self-gravity to overcome rigid body forces so that it assumes a hydrostatic equilibrium (nearly round) shape and (c) has cleared the neighbourhood around its orbit.
Basically, a planet such as Earth must orbit around the Sun and allow for its own self-gravity to pull itself along that orbit and clear its own path of other objects.
Dwarf planets, then, are classified as so because they do not meet the above criteria. There are also other factors that may classify an object as a dwarf planet: its size and its immediate surroundings. Dwarf planets are smaller than Mercury, and often orbit in areas that contain other objects.
Pluto, for example, is much smaller than Mercury (in fact, it’s slightly smaller than our own Moon!) and orbits through the Kuiper Belt, which contains billions of comets and other icy bodies. The Kuiper Belt is very similar to the asteroid belt between Mars and Jupiter (albeit much colder) where another dwarf planet, Ceres, is located.
Pluto, then, is considered a dwarf planet because – although it has a spherical orbital pattern around the sun, which is pulled by its own gravitational force – it is extremely small and surrounded by other objects.
In total, our solar system currently has five dwarf planets: Pluto, Ceres, Eris, Makemake and Haumea. Some of the largest known asteroids are currently being reviewed, and may be classified as dwarf planets in the coming years.
While many millennials are still distraught over the loss of Pluto’s planetary classification, it is has been receiving lots of attention in the past few months thanks to the New Horizons spacecraft.
New Horizons was launched nearly 9 years ago, and on July 14, 2015, will be making a historic flyby of Pluto. It has been, and will continue to, take photos of Pluto and its five known moons, which will continue to reveal new information and facts about these celestial bodies.
One new piece of information that has been revealed by New Horizons is the fact that this freezing, icy dwarf planet is actually red in colour! Make sure to follow the New Horizons spacecraft in the coming days for more ground-breaking information.
And make sure to watch our Star Lab Star Shows this summer to learn even more about the depths of our solar system and beyond!
- See more at: http://themuseum.ca/blog/themuseum-family-exhibitions-discovering-pluto#sthash.yrwfEN9G.dpuf
