Kepler-22 bThe jury is still out on Kepler-22b’s true nature; at 2.4 times Earth’s radius, it might even be gaseous. But theoretically an ocean world tipped on its side – a bit like our solar system’s ice giant, Uranus – turns out to be comfortably habitable based on recent computer modeling

Kepler-22b is an exoplanet that’s 2.4 times the size of Earth. It’s located 15 times closer to its star than Earth is to the sun. Kepler-22b has a similar sun to Earth’s, but it’s smaller and cooler. This close proximity to its star allows the planet to receive about the same amount of sunlight as Earth. The temperature on Kepler-22b could be about 15 to 22 degrees Celsius, similar to Earth’s spring weather

Recent estimates suggest that Kepler-22b has more than a 95% probability of being located in the empirical habitable zone. This zone is not too hot (so the water doesn’t evaporate) and not too cold (so it won’t freeze). 

However, a Kepler team member also suggested that the planet may not be able to host life on its surface. Astronomers believe that it “probably” also possesses water and land. 

Using a space shuttle, it would take 23.4 million years to reach Kepler-22b

It’s not possible to travel to an exoplanet without light-speed travel or suspended animation. Kepler-22b is 640 light-years away from Earth. At the speed of a space shuttle, it would take 23.4 million years to reach it

Kepler-22b is located in the constellation Cygnus. It’s about 640 light-years from Earth

NASA’s Kepler mission discovered Kepler-22b in December 2011. It was the first Kepler planet to be found in the habitable zone of its star. The habitable zone is the area around a star where temperatures are just right for liquid water to exist. 

Kepler-22b has an orbital period of 290 days. It’s unclear if this “super-Earth” planet is rocky, liquid, or gaseous

Yes, Kepler-22b has a sun. Kepler-22b orbits a G-class sun that’s similar to Earth’s sun, but smaller and cooler. The planet’s close proximity to its star allows it to receive about the same amount of sunlight as Earth

Kepler-22b’s first transit in front of its sun was observed in 2009. The Spitzer Space Telescope provided more data that confirmed Kepler-22b’s transits

NASA says that Kepler-22b could hold life.  It’s considered a promising place to look for life.  However, it’s still unclear what Kepler-22b is made of. It could be gaseous, or it could be an ocean world.  Computer modeling suggests that an ocean world could be habitable. 

Kepler-22b is an ocean planet, not a rocky planet like Earth. It has an estimated mass of 36 Earth masses and a radius of 2.38 Earth radii

Recent estimates suggest that Kepler-22b has more than a 95% probability of being located in the empirical habitable zone defined by the recent Venus and early Mars limits (based on estimates of when these planets may have supported habitable conditions), but less than a 5% chance of being located in the conservative

Kepler-22b is likely covered in water. It’s made up of rock, iron, ice, and water. Most of its surface is probably covered in an ocean. 

Kepler-22b is located in the habitable zone of its star, which means there’s a chance that liquid water exists on its surface. If there’s water, there’s also the possibility of life.

Large patches of clouds can also be seen. Kepler-22b has an estimated mass of 36 Earth masses and a radius of 2.38 Earth radii, making it a “super-Earth.” It is an ocean planet instead of having a rocky, Earth-like composition

Yes, Kepler-22b has large groups of clouds and visible jet streams. It’s possible that the planet has clouds in its atmosphere. 

Kepler-22b’s surface composition is unknown. However, it’s likely to have a volatile-rich composition with a liquid or gaseous outer shell. 

Kepler-22b is also known to have: 

• Water 
• Jet streams 
• Clouds 
• Average surface temperature of 72 degrees Fahrenheit (22 degrees Celsius): 
• Visible jet streams 
• Large groups of clouds 
• 290 day orbital period

Kepler-22b has an equilibrium temperature of -11°C (11°F). If the planet’s atmosphere has similar thermal properties to Earth’s, its average surface temperature would be 21°C (70°F). If the atmosphere has a similar greenhouse effect to Venus, the average surface temperature would be 460°C (860°F).

Kepler-22b’s climate might not be pleasant. The planet’s poles could be either flooded with sunlight or shrouded in darkness for six months of the year. However, if the planet has a super ocean that’s at least 50 meters deep, it could regulate the temperature extremes

A year on Kepler-22b is 290 days. Kepler-22b’s orbit is about 85% as large as Earth’s. Kepler-22b’s star is 25% dimmer than the sun. 

Here are the orbital periods of some other exoplanets: 

• Kepler-421b: 704 Earth days 
• Kepler-452b: 384.8 days 
• Kepler-16b: 229 days 
• Kepler-442b: 112 days 
• Kepler-62f: 267 days 
• Kepler-62e: 122 days

Kepler-22b’s orbital period is 289.9 days. Its orbit is about 85% as large as Earth’s. The semimajor axis of its orbit is 0.85 Astronomical Units. 

Kepler-22b is a super Earth. It has a mass of 9.1 Earths and a radius of 2.1 times Earth. 

Kepler-22b was discovered in 2011.

Kepler-22b is too dim to see with the naked eye. It has an apparent magnitude of 11.5. 

Exoplanets are hard to study because they are far away and dim compared to their host stars. The bright glare of the stars they orbit can also hide them from telescopes

Yes, there are exoplanets in the Milky Way. Astronomers have discovered 5,502 exoplanets in the Milky Way. This includes the eight planets in our solar system, making for a total of 5,510 known planets in our galaxy. 

Most of the exoplanets discovered are within thousands of light-years of the solar system. This is as far as current telescopes can see. 

Scientists have categorized exoplanets into the following types: Gas giant, Neptunian, Super-Earth, Terrestrial. 

Some examples of exoplanets include: 

• Proxima Centauri b This exoplanet is four light-years away from Earth and has a mass 1.27 times that of Earth. 
• ROXs 42 Bb This gas giant is nearly 500 light-years from Earth and has a radius estimated to be 1.12 times that of Jupiter.

To date, we know precious little about Kepler-22b, but what we do know stands in stark contrast to the world colonized by the characters of Raised by Wolves. There’s little evidence that the actual Kepler-22b resembles the world we see on screen in any way whatsoever. These worlds, the fictional and the real, seemingly share a name and nothing else.

KEPLER SPACE TELESCOPE

The search for worlds outside our solar system has been ongoing for centuries, but has really only taken shape in the last few decades. The first confirmed detection of an extra-solar world was confirmed only in the 1990s.

Since that time, more than 4,000 exoplanetshave been discovered, most of them by the Kepler Space Telescope, between 2009 and 2018.

Kepler used the transit method to detect extra-solar planets. Pointing itself at specific regions of the sky, Kepler would measure the apparent brightness of stars, looking for intermittent dips in the amount of light making its way to the aperture. A decrease in the apparent light suggested the transit of an object. But that wasn’t enough to confirm the existence of a planet. Any number of phenomena can cause a temporary reduction in the brightness of a star. That’s why Kepler required at least three dimming events at repeated intervals in order to confirm the existence of a planet.

Kepler was designed in such a way that it was able to continuously view an entire region of space, not just one specific star. This was important because transit events can be brief, and breaking contact might mean missing them

Popular headlines at the time of Kepler-22b’s discovery positioned it as though it were another Earth circling a distant star. That’s true only in the barest terms, when compared against the variety of worlds which exist in the galaxy.

In truth, despite its many similarities, Kepler would still look entirely alien to us if we had the chance to visit( full article source google)