major discovery! NASA and Google jointly announced the discovery of "The Second Solar System", AI plays a vital role
Figure 丨 Kepler telescope
In addition, the new discovery has one of the biggest bright spots, that is, this research result is done in cooperation with Google.NASA scientists use Google Machine Learning to analyze Kepler data more efficiently and accurately than traditional analytics.As a result, NASA believes Google's AI technology will help detect extraterrestrial life outside the solar system.
Figure 丨 Google CEO Sundar Pichai Twitter on the first time, this is indeed Google AI's another victory
Attend this conference are:
Paul Hertz, director of astrophysics at NASA's Washington headquarters;
Christopher Shallue, Google AI Senior Software Engineer;
Astronomer at the University of Texas at Austin, Andrew Vanderburg, NASA postdoctoral fellow at Sagan.
Jessie Dotson, Kepler project scientist at NASA's Ames Research Center.
AI + space exploration
For centuries, research has helped to make people realize that galaxies with many planets such as the solar system around a star are not unique in the universe.
Nowadays, with the help of telescopes, detectors, mainframe computers and other technologies, human beings gradually expand our observation beyond the solar system in which we live and pay more attention to the planets around other stars. Studying these celestial bodies called extrasolar planets will help us to explore the true nature of the universe in its deepest exploration.What else outside the earth? Are there any other planets that resemble the stars in the solar system? Or, are there similarities with the solar system?
Although new technologies can help find new stars, the difficulty of finding extrasolar planets is huge. Compared to their orbiting stars, extrasolar planets are smaller and do not glow - finding them as difficult as fireflies flying around the searchlights thousands of miles away.But with machine learning, Google and NASA made a breakthrough.
Figure Kepler 9 Kepler 90 is a sun-like star, and our solar system is the same, it also has eight planets, but the difference is that the distance between its eight planets is far smaller than the solar system, As you can see in the picture above, the outermost 8th planet Kepler 90h is less than the distance from our planet, Kepler 90, to the sun (about 150 million km between Japan and Earth). It is precisely because of the distance, so the planet revolution for a week is also very short time, with the discovery of Kepler 90i, for example, it revolutions only 14.4 days a week, by contrast, even in the solar system revolutions The fastest planet Mercury also takes 88 days a week.However, the distance means a very high temperature, Kepler 90i surface temperature of 800 degrees Fahrenheit (426 degrees Celsius), such a high temperature will certainly not allow any existence.After analyzing the structure of the Kepler 90 galaxy, astronomers found that the eight planets in the galaxy are distributed in a similar way to the solar system. Their original distribution distance is more dispersed, but only gradually "gathered" around the Kepler 90 of.
In general, the main way that astrophysicists used to look for extrasolar planets was to analyze a large number of data generated by the Kepler telescope through automated software or by hand. For the past four years, the Kepler telescope has observed about 200,000 stars, taking a picture every 30 minutes and creating about 14 billion data points. This 14 billion data points can be converted into about 2 trillion possible planetary orbit! For the computing power of the most computer, this analysis is also a huge project, and can be very time-consuming.To make such analysis faster and more efficient, researchers turned to machine learning.
Figure 丨 If a planet traverses in front of its precursor disc, one can observe a slight decrease in the apparent brightness of the star, depending on the magnitude of the planet relative to the star. This detection method is called "Lingri method", is one of the extraterrestrial planet detection method. The Kepler Space Telescope uses the Lingri method, which monitors over 100,000 stars over a long period of time, scans and records changes in the brightness of each star at different locations. This U-shaped pattern of light and dark signals is represented by white lines. The blue dotted distribution in the video is exactly what NASA has come to expect from Kepler's orbit after analyzing these light curves.
When a planet blocks some light, the brightness of the star diminishes.Based on this principle, the Kepler Space Telescope observed the brightness of 200,000 stars and spent four years looking for these characteristic signals caused by the planets running.
In fact, machine learning is particularly useful as a way of training patterns in computer recognition for understanding large amounts of data,The key bright spot is to let the computer "learn" spontaneously, rather than using specific programming.
Working together, Google's AI engineer Christopher Shallue teamed up with Andrew Vanderburg, an astrophysicist at the University of Texas at Austin, to teach how a machine learning system can identify planets around distant stars.
Using a dataset of Kepler signals over 15,000 markers, they created a TensorFlow model to distinguish between planets and non-planets.During testing, the system can accurately determine which signals are planets and which ones are not planets, with an accuracy of 96%.
Each point in the map represents a galaxy that has been discovered, and the number represents the number of planets that are in the galaxy. From the figure we can see that in the more than 2,000 galaxies known (at least one planet) The more planets the more rare galaxies. The discovery of the two planets means that it is possible that galaxies with more planets will be discovered.
To narrow the search, scientists studied 670 stars known to contain two or more extrasolar planets. Two new planets were finally discovered: Kepler 80g and Kepler 90i.Importantly, the Kepler 90i is the eighth planet in the Kepler 90 galaxy, which allows us to determine that the Kepler 90 is the first 8-planet galaxy we know outside the solar system.
The Figure 21 Kepler Space Telescope captured 30,000 planets suspected of orbiting a star. By training neural networks, researchers have learned to learn the faint signals that a planet crosses in front of a star. In scanning this known 670 multi-planet system using this technique, two planets were discovered: the Kepler 90i and the Kepler 80g.
The shape of the Kepler 90 galaxy is similar in shape to our solar system: a smaller number of orbiting orbiting stars and larger orbiting orbits of far stars. In the solar system, this planetary arrangement means that the principle planets will have lower temperatures and the water will be in solid form and accumulate to make the planets larger and larger. This law may also apply to the Kepler 90 galaxy.
Figure 21 When the Kepler Space Telescope was launched in 2009, we found only 326 planets outside the solar system, most of them similar in size to Jupiter, much larger than Earth.
Today, we have identified more than 3,500 exoplanets, of which more than 2,500 are found with reference to Kepler's telescope data. The size of these planets is between Earth and Jupiter. Thanks to the Kepler telescope, in just a few decades, humans have discovered more extrasolar planets.
In the figure, the orange area is the area that has been explored by the Kepler telescope, and there may be a large number of unidentified planets in the vast unexplored area (blue). Taking into account the powerful capabilities of the Kepler telescope, It is estimated there will be new discoveries coming soon.
Kepler telescope 5 found
The Kepler telescope, which launched in 2009, has discovered thousands of extrasolar planets, greatly deepening our understanding of the unknown universe beyond the solar system. In eight years, Kepler raised the number of extrasolar planets we know by one order of magnitude, of which five were the most prominent.
1, "Earth 2.0" Kepler 452b
In 2014, the Kepler telescope discovered the exoplanet 452b known as "Earth 2.0"On July 23, 2015, NASA officially announced the largest discovery so far, which is an important event in the history of human astronomy.
Kepler 452b means the nearest planet to the main star in the 452th constellation Galaxy that Kepler plans to discover. This planet is the most livable extrasolar extrasolar planet closest to Earth, Big discovery.
Figure 丨 Kepler 452b
The planet has many characteristics in common with our Earth: the revolution orbit is slightly larger than Earth, 60% of its diameter and 5 times the volume of Earth, and the Earth's surface is twice as gravitational as Earth and its distance from Earth and Earth The sun is close by, its stars are 1.5 billion years older than the sun and its luminosity is 1.2 times that of the sun.
Experts are not yet sure whether this planet has any life or not, and that it is heading for death. But if plants are transferred there, they may survive.
2, for the first time found that the planet double star running Kepler 16 (AB) b
In 2011, Kepler first discovered a giant planet orbiting two stars. The planet is named Kepler 16 (AB) b, which runs around two stars, regularly emitting light and darkness.When the two stars surround each other, the occultation of the solar eclipse occurs.
The strange planet runs around 229 Earths a week for two stars. The masses of Kepler 16A and Kepler 16B stars are 69% and 20% of the sun's mass, respectively. The two stars are very close to each other, averaging only one-fifth of the distance between Earth and Earth, which is closer than the distance between Mercury and the Sun. The time the two stars are surrounding each other for about 41 Earth days.
Discover the first exoplanet that is livable
On December 5, 2011, NASA announced that Kepler plans to discover Kepler 22b, the first extrasolar planet located in a habitable class of solar-like stars. Located within Cygnus, 600 light-years from Earth, the planet revolves around 22 kilometers of Kepler-like Sun-like stars.
Figure 丨 Kepler 22b
Although its diameter is much larger than that of the Earth, its orbit revolution period is about 290 days, which is not much different from that of the earth.According to Kepler's position in space, 22b extrapolates that the surface is likely to contain liquid water. If you are fortunate enough to have earth-like earth and atmosphere, its surface temperature is estimated to be about 22 degrees Celsius, making it more suitable for life survive.
4, Super Earth LHS 1140b
In April 2017, the Kepler binoculars found a "terrestrial planet" with livability and was the fifth exoplanet to be found in less than a year. This "Super Earth" code-named LHS 1140b, belongs to the rocky planets, the climate is not too hot nor too cold, not too far from the Earth, its stars 40 light years from Earth. LHS 1140b is a "super earth" with 40% more diameter than the Earth, 6.6 times the mass of Earth and three times the Earth's gravity.
5, the history of the most livable planetary system with terrestrial planets Trappist1
NASA announced the discovery of a very special "solar system" on the afternoon of February 22, 2017. There are seven planet-sized planets around the stars in this planetary system, most probably all solid-state planets, possibly with water on their surface; three of them The planet may be in the livable range, indicating that the temperature is just above it and there may be liquid water.This discovery has refreshed the records of the number of similar-type planets in the Livable Zone by extrasolar stars.
The star's mass in the galaxy is about 8% of the sun's radius, about 11% of the sun's radius, and its surface temperature is 2277 degrees Celsius. All seven planets have smaller orbital radii than Mercury's orbital radii and are very close to each other. They are likely to have been tidal locked, always only facing the central star, so the above climatic conditions and the earth is very different.
Figure 丨 Trappist1
In addition to the incident itself, the most noteworthy point of this discovery is that artificial intelligence has been involved in the field of space exploration. To date, scientists have used the model to search only 670 of the 200,000 stars, and many more exoplanets in Kepler's telescope data have not been found.however,With the help of new technologies such as machine learning, more and more celestial bodies will be discovered, and humankind's understanding of the universe and itself will also take a new step.