Scientists Discover The First Planets Outside The Milky Way

The truth is out there. And past that is a cluster of planets 3.8 billion light-years away, a recent discovery that if confirmed could extend the boundary of what we know about the universe.

Using data from a NASA X-ray laboratory in space, Xinyu Dai, an astrophysicist and professor at the University of Oklahoma, detected, for the first time ever, a population of planets beyond the Milky Way galaxy. The mass of the planets range in size from Earth's moon to the massive Jupiter, our solar system's biggest planet.

There are few methods to determine the existence of distant planets. They are so far away that no telescope can observe them, Dai told The Washington Post. So Dai and his postdoctoral researcher Eduardo Guerras relied on a scientific principle to make the discovery: Albert Einstein's Theory of Relativity.

10 Things To Know About Earth-Like Planets Found In Nearby Solar System

US space agency NASA has announced that scientists researching outer space have found the existence of another 'solar system' - seven Earth-like planets orbiting a small star in a galaxy 40 light years away - opening up the most promising hunting ground so far for life beyond. A press release from the space agency said the Spitzer Space Telescope has found that the planets are as large as Earth and are in a "habitable zone". All seven roughly match the size and mass of Earth and are almost certainly rocky. Three are perfectly perched to harbour life-nurturing oceans of water, they reported in the journal Nature.

1. "New record! We've found 7 Earth-sized planets in the habitable zone around a single star outside our solar system," NASA tweeted.
2. The system is around 40 light-years, which is 235 trillion miles, away from Earth, in a constellation called Aquarius. Because they are located outside of our solar system, these planets are scientifically known as exoplanets.
3. The exoplanet system is called TRAPPIST-1, named for The Transiting Planets and Planetesimals Small Telescope (TRAPPIST) in Chile.
4. The scientists have measured the density of six of the planets and say further research will show if they have water on their surface.
5. It is possible that all seven planets have water, "the key to life as we know it, under the right atmospheric conditions, but the chances are highest with the three in the habitable zone," NASA said.
6. The mass of the seventh planet is yet to be measured. But scientists say it is possible that it would be covered in ice.
7. Spitzer, an infrared telescope that trails Earth, was well-suited for studying TRAPPIST-1 because the star glows brightest in infrared light. Further studies involved the Hubble Space Telescope. Ij future the James Webb Space Telescope is expected to chip in.
8. For decades, there have been speculations about information regarding the existence of alien life forms - one of the biggest questions facing astronomers.
9. The search for life had started in 1995 after NASA's Kepler Space Telescope found signs of the first alternative solar system. Called Kepler 10b, it also signaled what NASA said could be a "small planet orbiting a star about 540 light years away".
10. "This discovery could be a significant piece in the puzzle of finding habitable environments, places that are conducive to life," said Thomas Zurbuchen of NASA. "Answering the question 'are we alone' is a top science priority and finding so many planets like these for the first time in the habitable zone is a remarkable step forward toward that goal."

Our Solar System

Ancient astronomers observed points of light that appeared to move among the stars.The Solar System comprises the Sun and the objects that orbit it.The Solar System formed 4.6 billion years ago from the gravitational collapse of a giant molecular cloud. The vast majority of the system's mass is in the Sun, with most of the remaining mass contained in Jupiter. The four smaller inner planets, Mercury, Venus, Earth and Mars, also called the terrestrial planets, are primarily composed of rock and metal. The four outer planets, called the gas giants, are substantially more massive than the terrestrials. The two largest, Jupiter and Saturn, are composed mainly of hydrogen and helium; the two outermost planets, Uranus and Neptune, are composed largely of substances with relatively high melting points (compared with hydrogen and helium), called ices, such as water, ammonia and methane, and are often referred to separately as "ice giants". All planets have almost circular orbits that lie within a nearly flat disc called the ecliptic plane.

Planet Saturn

Saturn is the sixth planet from the Sun and the second largest planet in the Solar System, after Jupiter. Named after the Roman god of agriculture, its astronomical symbol (♄) represents the god's sickle. Saturn is a gas giant with an average radius about nine times that of Earth. While only one-eighth the average density of Earth, with its larger volume Saturn is just over 95 times more massive