Jakarta, CNN Indonesia —
Planets outside the solar system or often called exoplanet become an object of research outer space experts. What are you really looking for in the research?
The US Aeronautics and Space Administration (NASA) has so far confirmed that there are more than 5,000 planets that fall into this category. Some of them are said to have a resemblance to Earth and are called ‘Super Earths’.
It is so called because of its size, which is on average 30 to 70 percent larger than Earth. An exoplanet can be composed of thick, rotating rock or gas or both.
The search for exoplanets, among other things, is carried out to look for the potential for life. “That was one of the fundamental questions we wanted to know,” said Ravi Kumar Kopparapu, exoplanet researcher at NASA’s Goddard Space Flight Center. Mashable.
That’s because some exoplanets may fall into the habitable category, aka allowing life to exist. “The planets are really interesting,” said exoplanet researcher at NASA’s Jet Propulsion Laboratory, Renyu Hu.
One example of an exoplanet that falls into this category is LP 890-9 c, which will be discovered in 2022. The planet has a rocky surface about 40 percent larger than Earth.
The planet also orbits in the habitable zone of its star. The habitable zone for living alone is the safe position of an exoplanet relative to its star so that liquid water is possible within the exoplanet.
However, an exoplanet that is in the habitable category does not necessarily make it have life. “A habitable planet can have life, but that doesn’t mean there already is life there,” said Kopparapu.
On Earth, humans could have gone to extreme remote places and found life there. But on exoplanets, “we can’t do that,” said Kopparapu.
From trillions of light years away, a body of concrete evidence must exist to support the claim that super-Earths may have life. According to Kopparapu, context is the most key thing.
These things include, is the exoplanet exposed to harmful radiation? Is there enough data from the telescope to make a computer simulation of the planet’s environment? Is there, then, an alternative way beyond life to explain how certain gases, such as methane, can be produced?
“We have to be careful. Nature can fool us in many ways,” he said.
Furthermore, astronomers may find a few exoplanets that are similar to Earth. It’s possible that the exoplanet is gas-dominated or doesn’t have rocky plains rising from the ocean.
However, this did not necessarily disappoint the experts. “In fact, I am even disappointed if the exoplanet is similar to Earth. We want to find a new world that is really strange,” said Kopparapu.
Using a Telescope
On the other hand, finding exoplanets is not easy. Special telescopes such as NASA’s TESS, must observe continuously and see changes in brightness levels.
The twinkling of a star may mean that a planet passes in front of the star. That means, there could be a new world or planet that is ready to be observed.
TESS has so far discovered more than 240 exoplanets, along with thousands of other candidates.
Once an exoplanet is found, astronomers then take a deeper look. One way is to use the most advanced telescope today, the James Webb Space Telescope (JWST).
JWST can detect the atmospheric composition of an exoplanet. Earth, for example, contains oxygen and nitrogen along with other gases such as carbon dioxide.
The JWST telescope also relies on flickering light in its observations. This is because the closest planet to Earth is trillions of kilometers away.
Apart from JWST, there is also a telescope called the Extremely Large Telescope (ELT) which is being built in the dark desert of Chile. The telescope will collect light passing through the exoplanet’s atmosphere.
That is done through the main mirror that stretches about 127 feet. The mirror allows a telescope in Chile to take photos of exoplanets.
“ELT will revolutionize the study of planets outside our Solar System,” wrote the European Southern Observatory. site official.
JWST and ELT may help humanity learn more about exoplanets. However, the means that humans have are still limited to study exoplanets in detail.
This is because a telescope like JWST still has to be at the perfect angle to see the twinkling of a star due to a passing exoplanet. “We won’t know much more until we have a much more sophisticated telescope,” said Kopparapu.
(lth/lth)
