On December 25, the largest and most powerful space telescope ever built NASA was successfully launched from Earth.
With unprecedented technology James Webb Space Telescope (JWST) will look both near and far, from the planets and bodies of our solar system to the deepest parts of space, where the first stars and galaxies were formed more than 13 billion years ago. JWST has a mirror that is 21.3 feet (6.5 meters) across, making it physically much larger than The Hubble Space Telescope and Hubble's sister infrared telescope, the Spitzer Space Telescope, powered by Caltech's IPAC; it also has state-of-the-art photon detectors that detect a wider range of wavelengths and enable deeper and more detailed views than the Spitzer.
The launch represents a major milestone for the project, which began building back in 2004. Following the launch, the telescope began a one-month odyssey to its observatory perch beyond the moon, an orbital location in space called the second Lagrange point or L2, which is around 1 million miles from Earth. Once there, JWST will complete a six-month process of commissioning after launch: it will unfold its mirrors, sunshade and other systems and cool down, adjust and calibrate.
"With March missions, they have something they call the 'seven minutes of terror' - the time window in which everything has to happen exactly to the landing, ”says Charles Beichman, senior faculty assistant in astronomy and director of the NASA Exoplanet Science Institute at Caltech. "For JWST, it's a kind of 29-day fear that everything will happen perfectly."
Beichman, whose primary research focus is planets outside our solar system, or exoplanets, is a member of the science team for one of JWST's instruments, the Near Infrared Camera (NIRCam). NIRCam will detect light from the earliest stars and galaxies while in the process of formation, as well as from populations of stars in nearby galaxies; young stars in our The Milky Way galaxies; planets orbiting nearby stars; and the Kuiper Belt objects at the edge of our solar system. Using a set of coronographic masks developed at Jet Propulsion Laboratory (JPL), which Caltech manages for NASA, to block the clear glow of host stars, Beichman and the NIRCam team will search for Saturnexoplanets the size of bright nearby stars including epsilon Eri and Vega.
NIRCam is one of four major JWST instruments for observing the sky at different wavelengths. The other three are the Mid-Infrared Instrument (MIRI), which will observe light from distant galaxies, newly formed stars and faintly visible comets, as well as objects in the Kuiper Belt; Near InfraRed Spectrograph (NIRSpec), which will perform high-resolution spectroscopic observations of 100 cosmic objects simultaneously; and Fine Guidance Sensor / Near Infrared Imager and Slitless Spectrograph (FGS / NIRISS), which will perform lower resolution spectroscopic measurements to characterize the light from the universe's first stars and exoplanets. The MIRI instrument was developed jointly by JPL and the European Space Agency.
Once the telescope is complete with its setup, Caltech scientists are already among those approved to perform observations. In collaboration with astronomy professor Dimitri Mawet, who is also a JPL scientist, and Caltech postdoc Jorge Llop Sayson, Beichman and an international team of scientists have received approval to observe Alpha Centauri, the closest sun-like star on Earth, and determine whether it has a planet orbiting it - more specifically a gas planet the size of Jupiter. Future telescopes may be looking for even smaller planets. Alpha Centauri is only 4.3 light-years away from Earth.
Another main goal of the telescope will be to characterize the composition and physical properties of exoplanets. Together with a team led by graduate student Michael Zhang (MS '18), Caltech professor of planetary science Heather Knutson will use the MIRI instrument to study an ultra-hot planet smaller than Earth, whipping around a nearby star in a eight-hour circuit.
Other observers plan to use the MIRI instrument to observe Earth-sized planets in the TRAPPIST-1 system explored by the Spitzer Space Telescope to characterize the atmospheric compositions of potentially habitable Earth-like planets for the first time. Overall, Caltech and JPL exoplanet scientists, including postdoctoral fellow Jessica Spake, visiting associate Renyu Hu, also from JPL, and JPL researcher Tiffany Kataria, were successfully successful in receiving JWST time to study exoplanets. In addition to exoplanet studies, Caltech scientists will use JWST to make cosmological measurements and study distant galaxies.
For example, IPAC employee Andreas Faisst and his team will use the NIRCam and MIRI instruments to study a part of the sky nicknamed COSMOS. Few stars and no gas clouds in our galaxy block our view of this area; it was famously imaged by Hubble and Spitzer, and follow-up data from the Keck Telescopes and other terrestrial observatories were obtained to study how galaxies are affected by both their basic physical properties and the environment around them - a kind of study of nature and nutrition. in galactic evolution.
JWST is expected to expand this work by providing unparalleled spatial resolution image data to study the structure of distant galaxies and local star formation sites in them and to find and characterize the very first galaxies in our universe from more than 13.5 billion years in the past, "says Faisst." In addition, it will revolutionize our understanding of the universe's most massive galaxies and, in particular, answer the question of why some of them have stopped forming stars. "
Beichman emphasizes that JWST is transformative in its ability to study a wide range of objects near and far, from those in our solar system to the most distant parts of the universe. "It will serve entire astronomical and solar system societies with unprecedented capabilities," he says. "Compared to any previous telescope, ground or space-based, the JWST has a revolutionary ability to take both images and spectra at infrared wavelengths."