NASA has confirmed that there are more than 5,000 known planets outside our solar system, known as exoplanets.
The US space agency has added 65 more exoplanets to NASA’s online archive of exoplanets, bringing the grand total to 5,005.
The exoplanets found so far include small rocky worlds like Earth, gas giants several times larger than Jupiter, and “hot planetesimals” in very close orbits around their stars.
However, NASA asserts that 5005 is only a “small fraction” of all the planets in the Milky Way alone, which could number into the hundreds of billions.
NASA confirms that there are more than 5,000 planets outside our solar system including many “hot Jupiters”, “super-Earths” and “mini-Neptunes”. Depicted here by an artist’s impression of a variety of different exoplanets
“It’s not just a number,” said Jesse Christiansen, a research scientist at the NASA Exoplanet Science Institute at the California Institute of Technology in Pasadena, California.
Each of them is a new world, a completely new planet. I get excited about everyone because we don’t know anything about them.
The majority of the outer planets are gaseous, such as Jupiter or Neptune, not Earth, according to NASA’s online database.
The archive records discoveries of exoplanets that appear in peer-reviewed scientific papers that have been confirmed using multiple detection methods or by analytical techniques.
between the Recently confirmed exoplanets It is K2-377 b, a “super-Earth” with a mass of 3.51 Earths that takes 12.8 days to complete one orbit of its star.
Another, called TOI-1064 b, is “a rocky world potentially larger than Earth, according to NASA.
Most exoplanets are found by measuring the opacity of a star that happens to have a planet passing in front of it, called the transit method.
Another method for detecting exoplanets, called the Doppler method, measures the “wobbles” of stars due to the gravitational force of orbiting planets.
The more than 5,000 confirmed exoplanets in our galaxy to date include a variety of species – among them a mysterious variety known as ‘super-Earths’ because it is larger than our world and possibly rocky
The NASA milestone comes 30 years after the discovery of the first exoplanets, in 1992.
In January of that year, Alexandre Volszan and Del Vriel announced the discovery of two rocky planets orbiting PSR B1 257 + 12, a pulsar in the constellation Virgo. Another planet was discovered in the system in 1994.
Finding just three planets around this rotating star essentially opened the doors to exoplanets, said Wolszczan, who is still searching for exoplanets as a professor at Penn State University.
“If you can find planets around a neutron star, the planets have to be basically everywhere,” he told NASA. “The planet’s production process must be very robust.”
Some of the exoplanets that have since been discovered, like Kepler 16-b, orbit two stars simultaneously, like Planet Tatooine in the Star Wars movie.
About 200 light-years away, Kepler-16b weighs about one-third the size of Jupiter and has a radius of three-quarters of Jupiter, making it similar to Saturn in size and mass.
Another exoplanet called WASP-121b, about 850 light-years from Earth, is an example of a “hot Jupiter” – a giant Jupiter-like gas planet in close orbit around its parent star.
WASP-121b has one of the shortest orbits yet discovered, orbiting its star in just 30 hours.
It is gradually locked, which means that the same side is always facing its star, while it is cooler The “night” side is forever oriented towards space.
Gliese 486b, meanwhile, is an example of a “super-Earth” – a planet larger than Earth but smaller than the four gas giants Jupiter, Saturn, Neptune, and Uranus.
Some exoplanets orbit two stars at once, like Tatooine in the 1977 movie Star Wars (pictured)
Artist’s impression of the exoplanet Kepler-16b, the most “Tatooine-like” planet in our galaxy to date. Kepler-16b is depicted as a small black circle orbiting two stars. The two largest stars, a K dwarf, have a mass of about 69% that of our Sun, and the smallest, a red dwarf, that has a mass of about 20% that of our Sun.
Gliese 486b is the only planet discovered so far that orbits the young star with a radius 1.3 times larger than Earth but 2.8 times larger.
The planet has an iron silicate composition similar to that of Earth but much hotter, with a surface temperature of 802 degrees Fahrenheit (428 degrees Celsius), according to a 2021 study.
Meanwhile, GJ 367 b is exposed to a huge amount of radiation, due to the small distance from its star – about 620,000 miles – that it orbits in just eight hours.
With a diameter of 5,560 miles, GJ 367 b is slightly larger than Mars (4,200 miles) but has the composition of Mercury.
NASA said its James Webb Space Telescope (shown here in space) will capture light from the atmospheres of exoplanets to read the gases present to identify warning signs of conditions for life.
Scientists are still trying to learn more about what exoplanets and their atmospheres are.
NASA said its James Webb Space Telescope will capture light from the atmospheres of exoplanets to read the gases present to determine signs of habitable conditions.
The $10 billion (£7.4 billion) observatory, which was launched on Christmas Day, will explore the universe in the infrared spectrum, allowing it to peer into the clouds of gas and dust where stars are born.