James Webb Telescope: A Cool View on How Stars and Planets form
Article by: Andacs Robert Eugen, on 09 April 2022, at 08:48 am Los Angeles time
When science wants to evolve and people want to see the immense progress we've made over the last few decades, Webb will be one of the main proofs.
The ongoing multi-instrument optics alignment process for NASA's Webb telescope's near-infrared instruments is already having significant success. No wonder, Webb has already exceeded our expectations, but we still have to wait until a final verdict. Webb's images and research have barely begun. After this summer, we will probably see some spectacular images captured by Webb.
***For those who said they were disappointed with Webb's first image and probably expected Webb to see the aliens: Well, Webb wasn't designed to take pictures of aliens, and regarding with the first image captured, Webb still has to align its tools. And Webb caught a star and exceeded expectations. The details in the picture are fascinating anyway. And this is still the first image...
According to some announcements, Webb would be able to detect life on other planets. But we can't confirm that yet. However Webb's main goal is to help us see the past of our Universe. We will see the rest of the secondary objectives along the way.
In any case, the team coordinating Webb will begin a cooling process for the Webb telescope's near-infrared instruments. In addition, the team will have to stay focused on cooling the Mid-InfraRed instrument (MIRI) to a temperature of 7 K (Kelvin), according to NASA.
It was known from the beginning that Webb needed some time for a larger cooling process for most major instruments, such as the backplane, mirrors, the MIRI instrument, and the near-infrared instruments. They must be cooled to their operating temperature.
In the latest post from NASA's James Webb Telescope website, Klaus Pontoppidan, the Space Telescope Science Institute project scientist for Webb explains how Webb will see the formation of planets and stars in our galaxy, the Milky Way:
"In the first year of science operations, we expect Webb to write entirely new chapters in the history of our origins - the formation of stars and planets. It is the study of star and planet formation with Webb that allows us to connect observations of mature exoplanets to their birth environments, and our solar system to its own origins. Webb's infrared capabilities are ideal for revealing how stars and planets form for three reasons: Infrared light is great at seeing through obscuring dust, it picks up the heat signatures of young stars and planets, and it reveals the presence of important chemical compounds, such as water and organic chemistry.
"Let us look at each reason in more detail. We often hear that infrared light passes through obscuring dust, revealing newborn stars and planets that are still embedded in their parental clouds. In fact, mid-infrared light, as seen by MIRI, can pass through 20 times thicker clouds than visible light. Because young stars are formed quickly (by cosmic standards, anyway) - in as little as a few 100,000 years - their natal clouds have not had time to disperse, hiding what is going on in this critical stage from visible view. Webb's infrared sensitivity allows us to understand what happens at these very first stages, as gas and dust are actively collapsing to form new stars.
"The second reason has to do with the young stars and giant planets themselves. Both begin their lives as large, puffy structures that contract over time. While young stars tend to get hotter as they mature, and giant planets cool, both typically emit more light in the infrared than at visible wavelengths. That means that Webb is great at detecting new young stars and planets and can help us understand the physics of their earliest evolution. Previous infrared observatories, like the Spitzer Space Telescope, used similar techniques for the nearest star-forming clusters, but Webb will discover new young stars across the galaxy, the Magellanic Clouds, and beyond.
"Finally, the infrared range (sometimes called the "molecular fingerprint region") is ideal for identifying the presence of a range of chemicals, in particular water and various organics. All four of Webb's science instruments can detect various important molecules using their spectroscopic modes. They are particularly sensitive to molecular ices present in cold molecular clouds before stars are formed, and NIRCam and NIRSpec will, for the first time, comprehensively map the spatial distribution of ices to help us understand their chemistry. MIRI will also observe warm molecular gas near many young stars where rocky, potentially habitable planets may be forming. These observations will be sensitive to most bulk molecules and will allow us to develop a chemical census at the earliest stages of planet formation. It is no surprise that a significant number of Webb's early scientific investigations aim to measure how planetary systems build the molecules that may be important for the emergence of life as we know it.
"We will be keeping a close eye on MIRI as it cools down. As the only mid-infrared instrument on Webb, MIRI will be particularly important for understanding the origins of stars and planets."
Said Klaus Pontoppidan, Webb project scientist, Space Telescope Science Institute.