Hades is the god of the underworld.
IF all planets were formed form a single disc of dust, should they ALL be co-planar? That was not the intention of the person who coined the term, Dr. In astronomy, dwarf stars are still stars, and dwarf galaxies are still galaxies.
He was asking the same kind of questions scientists ask. Does it make any sense that a massive gaseous celestial body such as Jupiter would be declared under the same name as a relatively minuscule terrestrial planet like Mercury?
Yes, you know why? Yet for some reason, in spite of the fact that there is more in common in volume, mass and composition between Earth and Pluto than there is between Earth and Saturn we still call Saturn a planet and Pluto a dwarf or twin planet. Angela Zalucha Key Is pluto a planet But you also bring up a good point about gas giants vs.
As the number of exoplanets that have been observed increases, some are more Jupiter like than star like. The definition of a main sequence star is an object that sustains nuclear fusion.
So then, rhetorically, are they planets? Angela Zalucha Fair point. But we think Jupiter and the sun do have physical surfaces, sort of.
One day when it becomes feasible to go deep enough we may have another argument…. So then how come nobody lost their marbles over this?
Settle down Pluto people…. They may have fused deuterium rather than hydrogen. We need a schematic for planets similar to the Herzsprung-Russell Diagram for stars. That or we need to seriously look at the Star Trek planet classification system.
We talking about the general public here, not cosmologists. When scientists in any field talk to laymen they must simplify their language or risk not being understood.
Indeed, this goes for any expert in any field since all fields of expertise develop their own jargon that the layman will not understand.
A dictionary of astronomical terms would be a book intended for astronomists, cosmologists, etc. A dictionary which will contain a few astronomical terms will be specially written to be comprehensible to the general reader.
Scientist to scientist, precise definitions are necessary, and to be expected; scientist to layman, simpler definitions are likely to be necessary; layman to layman, the most basic definitions are likely to be used which can even be totally false and produce no communication of any intellectual meaning but which may still have different kinds of meaning e.
Yet when my kids were going to school during that time, they were still taught that Pluto was the 9th planet. Angela Zalucha its semimajor axis makes it the former 9th planet http: According to the geophysical planet definition, it is the tenth planet from the Sun.
And your statement is contradictory, NASA pays my salary. I am not some anonymous internet person, I post under my own name, google me.
For all intents and purposes, Earth is extremely round, even factoring in its topographical features. TalkingMoose Sorry to dispute your supposition, but if you removed the water from the surface of the earth, it would appear just as spherical as it does now, for all intents and purposes.Pluto revolves around the Sun in an orbit that is not exactly circular, much like the rest of the planets.
Rather, its orbit is more of an oval or egg shape. Because of this, Pluto will orbit inside of Neptune’s orbit. At times, this makes Pluto closer to the Sun than Neptune.
Also, its orbit does not lie flat in the same plane as the rest of the planets. Since Pluto is so far from Earth, little was known about the dwarf planet's size or surface conditions until , when NASA's New Horizons space probe made a close flyby of Pluto.
New Horizons. Feb 21, · A group of NASA scientists has proposed a new definition of what constitutes a planet, possibly opening the door for Pluto to return to its former status.
Nasa's New Horizons mission made a close pass of Pluto this week. For more than 70 years, Pluto was one of nine planets recognised in our Solar System. But in , it was relegated to the status. This work is licensed under a Creative Commons Attribution-NonCommercial License.
This means you're free to copy and share these comics (but not to sell them). More details. The process of new discoveries spurring a contentious refinement of Pluto's categorization echoed a debate in the 19th century that began with the discovery of Ceres on January 1, Astronomers immediately declared the tiny object to be the "missing planet" between Mars and Jupiter.