NASA discovers a planet the size of an earth in the ‘habitable zone’ of a star
NASA’s specialized planetary spacecraft in search of signs of extraterrestrial life has seen a world the size of an earth in the habitable zone of its star.
Post-synchronized TOI 700 p, the planet is only 100 light-years away and is slightly larger than the earth.
It has a much faster orbit than the Earth and only takes 37 days to complete a journey around its star.
TOI 700 d also receives only 86 percent of the energy that the earth does, because its star is about 40 percent of the mass of our sun and only half as hot.
Its presence in the habitable zone and its size offers hope that it can contain liquid water, but this has not yet been confirmed.
The breakthrough of the TESS spacecraft was announced at the annual meeting of the American Astronomical Society in Honolulu, Hawaii.
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After synchronized TOI 700 p, the planet is only 100 light-years away, exceptionally close on the scale of the space. It is slightly larger than the earth and has a much faster job time of just 37 days
TESS found three planets around the star, with only one within the habitable zone, where the liquid water temperature would remain on the surface.
“TESS has been specifically designed and launched to find Earth-sized planets orbiting nearby stars,” said Paul Hertz, director of NASA’s astrophysics department.
The exoplanet – a world that revolves around a star that is now our sun – was almost missed by astronomers after an initial error had incorrectly categorized the star and its planets.
Scientists wrote off the planets as non-viable for extraterrestrial life because they were considered too large and too hot.
But a team of amateur astronomers, including a high school student, identified the error and corrected it.
“When we corrected the star’s parameters, the size of its planets dropped and we realized that the outer one was about the size of the Earth and in the habitable zone,” said Emily Gilbert, a graduate student at the University of Chicago.
The discovery was later confirmed by the Spitzer Space Telescope.
Similar planets have already been identified, including some seen by the now-defunct Kepler Space Telescope.
But this is the first such world that TESS saw after its launch in 2018.
TESS sees distant planets with a patient approach, studies the image of stars in a specific area of the night sky and waits for objects to pass before.
These passages often indicate the presence of a planet that moves around the star and the decline in star brightness is analyzed to provide clues about the size, velocity, and chemical composition of the world’s atmosphere.
TESS found three planets around the star, with only one within the habitable zone, where the liquid water temperature would remain on the surface. Pictured a simulation for liquid water on the surface of the planet with TOI 700d in the habitable zone
WHAT IS TIDAL LOCKING?
Tidal lock is the phenomenon where a moon appears in place around a planet, with only one side visible.
This happens when the rotation period – time required to rotate 360 ° – is the same as the time required to complete a job.
The lunar cycle is an example of this, where the moon completes a journey around the earth every 28 days, while it takes a while to turn around completely.
it is because of the tidal lock that the ‘dark side of the moon’ exists.
But despite the best efforts of astronomers, the scientists still don’t know what the planet is made of, but they do computer simulations to find out.
The planet is nicely locked to the star, which means that one side is always facing the star, as is the case with the moon and the earth.
One simulation involved an ocean-covered TOI 700 d with a dense, carbon-dominated atmosphere similar to what scientists suspect that Mars was surrounded when it was young.
This synchronous rotation meant that, in another model, one side of the planet was constantly covered with clouds.
Another model predicts that the planet will be TOI 700 d as a cloudless, all-land version of modern earth, where winds flow away from the planet’s night side and converge at the point directly opposite the star.
A third simulation predicted an entire country world, where winds flow from the dark side of the planet to the light side.
Multiple astronomers will be observing the planet with other instruments to obtain new data that may match one of the NASA models.
HOW SCIENTISTS STUDY THE ATMOSPHERE OF EXOPLANETS?
Distant stars and their rotating planets often have different circumstances than everything we see in our atmosphere.
To understand this new world, and what they are made of, scientists must be able to detect what their atmosphere consists of.
They often do this using a telescope similar to Nasa’s Hubble telescope.
These huge satellites scan the sky and hold onto exoplanets that NASA may find interesting.
Here the on-board sensors perform various forms of analysis.
One of the most important and useful is called absorption spectroscopy.
This form of analysis measures the light that comes from the atmosphere of a planet.
Each gas absorbs a slightly different wavelength of light, and when this happens, a black line appears on a full spectrum.
These lines correspond to a very specific molecule, indicating that it is present on the planet.
They are often called Fraunhofer lines after the German astronomer and physicist who first discovered them in 1814.
By combining all the different wavelengths of light, scientists can determine all the chemicals that form the atmosphere of a planet.
The key is that what is missing gives the clues to find out what is present.
It is vital that this is done by space telescopes, because then the Earth’s atmosphere would interfere.
Absorption by chemicals in our atmosphere would warp the sample, so it is important to study the light before it has had the chance to reach the earth.
This is often used to search for helium, sodium and even oxygen in alien atmospheres.
This diagram shows how light passing through a star and the atmosphere of an exoplanet produces Fraunhofer lines that indicate the presence of important compounds such as sodium or helium