The order of the planets in the solar system, starting nearest the sun and working outward is the following: Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, Neptune and then the possible Planet Nine.
The solar system extends from the sun, goes past the four inner planets, through the asteroid belt to the four gas giants and on to the disk-shaped Kuiper Belt and far beyond to the teardrop-shaped heliopause.
Scientists estimate that the edge of the solar system is about 9 billion miles (15 billion kilometers) from the sun. Beyond the heliopause lies the giant, spherical Oort Cloud, which is thought to surround the solar system.
Ever since the discovery of Pluto in 1930, kids grew up learning that the solar system has nine planets. That all changed in the late 1990s when astronomers started arguing about whether Pluto was indeed a planet. In a highly controversial decision, the International Astronomical Union ultimately decided in 2006 to designate Pluto as a "dwarf planet," reducing the list of the solar system's true planets to just eight.
If you insist on including Pluto, it would come after Neptune on the list. Pluto is truly way out there and on a wildly tilted, elliptical orbit (two of the several reasons it was demoted).
Astronomers, however, are still hunting for another possible planet in our solar system, a true ninth planet, after mathematical evidence of its existence was revealed on Jan. 20, 2016. The alleged "Planet Nine," also called "Planet X," is believed to be about 10 times the mass of Earth and 5,000 times the mass of Pluto.
The inner four planets closest to the sun — Mercury, Venus, Earth and Mars — are often called the "terrestrial planets" because their surfaces are rocky. Pluto also has a rocky, albeit frozen, surface but has never been grouped with the four terrestrials.
The four large outer worlds — Jupiter, Saturn, Uranus and Neptune — are sometimes called the Jovian or "Jupiter-like" planets because of their enormous size relative to the terrestrial planets. They're also mostly made of gases like hydrogen, helium and ammonia rather than of rocky surfaces, although astronomers believe some or all of them may have solid cores.
Jupiter and Saturn are sometimes called the gas giants, whereas the more distant Uranus and Neptune have been nicknamed the ice giants. This is because Uranus and Neptune have more atmospheric water and other ice-forming molecules, such as methane, hydrogen sulfide and phosphene, that crystallize into clouds in the planets' frigid conditions, according to the Planetary Society. For perspective, methane crystallizes at minus 296 Fahrenheit (minus 183 degrees Celsius), according to the U.S. National Library of Medicine.
Are there other solar systems in the Milky Way?
Yes, so many! If you had asked anyone just 30 years ago, the answer would have been "we don’t know". But since then we have discovered already more than 5,000 planets orbiting stars other than our sun (so-called exoplanets). And since often we find multiple of them orbiting the same star, we can count about 4,000 other solar systems
Visit Our Website: https://astronomy.sfconferences.com/ Our Conference Nomination:https://x-i.me/astrocon Visit Our Award Nomination: https://x-i.me/astronom Contact us :htt/astronomy.sfconferences.com/ Get connect============== Face Book:https://www.facebook.com/profile.php?id=100090440442457 twitter: https://twitter.com/astronomyconfer instagram: https://www.instagram.com/isabella_aria21/ blogger:https://astrophysics23.blogspot.com/ pinterest: https://in.pinterest.com/astronomyc/
No comments:
Post a Comment