Skip to main content

Pluto-The controversial planet




Pluto has been our favorite planet since 2006. The reason why I wrote this blog is because NASA is ready to explore the planet and study it closely through its mission New Horizons. So before we get to know about this mission, let’s first get to know about Pluto.

HISTORY:

Pluto was discovered on February 18, 1930 in the Kuiper Belt. Kuiper belt is a ring of bodies beyond Neptune. Originally Pluto was considered as the ninth planet in solar system. But studying its size, mass, density etc. the International Astronomical Unit (IAU) defined the term “planet”. The definition goes as-
“planet is a body that orbits the Sun, is massive enough for its own gravity to make it round, and has cleared its neighbourhood" of smaller objects around its orbit.”
 According to this definition, Pluto could not be classified as a planet and hence was reclassified as a “dwarf planet” in 2006.

Although it is a dwarf planet compared to other eight planets, it is the second most massive dwarf planet known.

PLUTO’S COMPOSITION AND ITS SURFACE:

Pluto is primarily made of ice and rock. It is relatively small- about one-sixth the mass of the moon and one-third of its volume. Pluto’s icy surface is made of 98% Nitrogen. Methane and traces of carbon monoxide is also present.

PLUTO’S ORBIT:

Pluto orbits Sun at a distance of 4.4-7.4 billion kilometers. It has rather an unusual orbit. It is usually farther from Sun than other planets. However, due to eccentricity of its orbit, it is closer than Neptune for 20 years out of its 249 years orbit. Pluto crossed Neptune’s orbit on January 21, 1979; made its closest approach to Sun on September 5, 1989 and remained within Neptune’s orbit until February 1999. This will not occur again until September 2226. Pluto’s rotation period is of six days. Light from sun takes 5.5 hours to reach Pluto’s surface!

PLUTO’S CONTROVERSY:             

Till 2006, Pluto was considered as the ninth planet of the solar system. But after IAU defined the term “planet”, it was excluded and reclassified as a dwarf planet. But now the team of scientists working on New Horizons mission has proposed a new definition which will again include Pluto as a planet. The new definition proposed is as follows-
“A planet is a sub-stellar mass body, that has never undergone nuclear fusion and that has sufficient self-gravitation to assume a spheroidal shape adequately described by triaxial ellipsoid regardless of its orbital parameter.”
The team has decided to propose this new definition, after studying the planet closely.
Even if IAU decides to accept this new definition, it will take some time to become official. Till then Pluto will just have to wait.

Labels:

Comments

Post a Comment

Popular posts from this blog

Super Void

As mysterious as it can get, Universe has always been a place for strange and weird things. Now, scientists have a “Super-Void” in space which is missing galaxies! So before we get in to the topic, first let’s discuss what is “Void” According to Wikipedia, Voids or Cosmic Voids , as they are called, are vast spaces between galaxy filaments in the universe, which has few or 0 galaxies. Galaxy filaments are largest know structures in the universe, which have thread-like structures. They form boundaries between voids in space. These voids have very less density of matter that is considered for typical observable universe. Voids are believed to be formed in Big Bang, followed by massive collapse its mass and compressed by Baryonic matter . After Big Bang, there were lots of areas with high and low densities, which were changing rapidly. The regions with high density collapsed rapidly under gravity eventually causing foam-like structure of cosmic web of voids. Voids loc...
1 comment
Read more

New Horizons Spacecraft

New Horizons spacecraft is launched with primary mission to flyby Pluto and its moons and study them. But before we get into this blog, read the previous blog about the planet Pluto and get an overall idea about the planet. Now that you have read about Pluto’s history, orbit and composition let’s get into this NASA’s New Frontiers Program- New Horizons.   New Horizon is space probe which was launched on January 19, 2006.It is engineered by Johns HopkinsUniversity   Applied Physics Laboratory  (APL) and the  Southwest ResearchInstitute  (SwRI), with a team led by  S. Alan Stern . The name “New Horizons” was derived from Pluto’s moons, Nix and Hydra. The first letters of their names, N and H are initials of New Horizons. MISSION: The primary mission of New Horizons spacecraft is to study Pluto and study one or more Kuiper belt objects.   Originally the mission was to explore the undiscovered planets and objects in the solar system. Thi...
Post a Comment
Read more

Black Hole

“Black holes are where God divided by zero” – Albert Einstein.  Black holes are giant black bodies in the outer space, which have baffled the minds of many! Many believe their existence as an enormous body that pulls everything in and destroys it and many other believe their existence as a place where time stops and freezes everything. But apart from these beliefs, there are real questions like: how black hole is formed? How it was discovered and what are the theories that explain the nature of the black hole. Black holes are formed when a star collapses upon itself. In short, a star causes a supernova and explodes to form a black hole. Simple enough, isn’t it? Now let’s get into the discovery of black hole and many theories surrounding it. BEGINNING OF BLACK HOLE THEORY:   The idea of Black hole was first put forth in the 18 th century by John Michell. He put forth this idea in a letter published in 1783-84. The calculations in the letter assumed that ...
Post a Comment
Read more