Will We Know if TRAPPIST-1e has Life?

Artist's impression of the Archean Eon. Credit: Tim Bertelink/Wikimedia

The search for extrasolar planets is currently undergoing a seismic shift. With the deployment of the Kepler Space Telescope and the Transiting Exoplanet Survey Satellite (TESS), scientists discovered thousands of exoplanets, most of which were detected and confirmed using indirect methods. But in more recent years, and with the launch of the James Webb Space Telescope (JWST), the field has been transitioning toward one of characterization. In this process, scientists rely on emission spectra from exoplanet atmospheres to search for the chemical signatures we associate with life (biosignatures).

However, there’s some controversy regarding the kinds of signatures scientists should look for. Essentially, astrobiology uses life on Earth as a template when searching for indications of extraterrestrial life, much like how exoplanet hunters use Earth as a standard for measuring “habitability.” But as many scientists have pointed out, life on Earth and its natural environment have evolved considerably over time. In a recent paper, an international team demonstrated how astrobiologists could look for life on TRAPPIST-1e based on what existed on Earth billions of years ago.

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You Can't Know the True Size of an Exoplanet Without Knowing its Star's Magnetic Field

Artist's impression of a "hot Jupiter" orbiting close to a Sun-like star. Credit: NASA

In 2011, astronomers with the Wide Angle Search for Planets (WASP) consortium detected a gas giant orbiting very close to a Sun-like (G-type) star about 700 light-years away. This planet is known as WASP-39b (aka. “Bocaprins”), one of many “hot Jupiters” discovered in recent decades that orbits its star at a distance of less than 5% the distance between the Earth and the Sun (0.05 AU). In 2022, shortly after the James Webb Space Telescope (JWST) it became the first exoplanet to have carbon dioxide and sulfur dioxide detected in its atmosphere.

Alas, researchers have not constrained all of WASP-39b’s crucial details (particularly its size) based on the planet’s light curves, as observed by Webb. which is holding up more precise data analyses. In a new study led by the Max Planck Institute for Solar System Research (MPS), an international team has shown a way to overcome this obstacle. They argue that considering a parent star’s magnetic field, the true size of an exoplanet in orbit can be determined. These findings are likely to significantly impact the rapidly expanding field of exoplanet study and characterization.

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Webb Sees a Galaxy Awash in Star Formation

Starburst galaxy M82 was observed by the Hubble Space Telescope in 2006, which showed the galaxy’s edge-on spiral disk, shredded clouds, and hot hydrogen gas. The James Webb Space Telescope has observed M82’s core, capturing in unprecedented detail the structure of the galactic wind and characterizing individual stars and star clusters. Credit: NASA/ESA/CSA/STScI/Alberto Bolatto (UMD)

Since it began operations in July 2022, the James Webb Space Telescope (JWST) has fulfilled many scientific objectives. In addition to probing the depths of the Universe in search of galaxies that formed shortly after the Big Bang, it has also provided the clearest and most detailed images of nearby galaxies. In the process, Webb has provided new insight into the processes through which galaxies form and evolve over billions of years. This includes galaxies like Messier 82 (M82), a “starburst galaxy” located about 12 million light-years away in the constellation Ursa Major.

Also known as the “Cigar Galaxy” because of its distinctive shape, M82 is a rather compact galaxy with a very high star formation rate. Roughly five times that of the Milky Way, this is why the core region of M82 is over 100 times as bright as the Milky Way’s. Combined with the gas and dust that naturally obscures visible light, this makes examining M82’s core region difficult. Using the extreme sensitivity of Webb‘s Near-Infrared Camera (NIRCam), a team led by the University of Maryland observed the central region of this starburst galaxy to examine the physical conditions that give rise to new stars.

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Webb Finds Hints of a Third Planet at PDS 70

An artist's illustration of the PDS 70 system, not to scale. The two planets are clearing a gap in the circumstellar disk as they form. As they accrete in-falling material, the heat makes them glow. Image Credit: W. M. Keck Observatory/Adam Makarenko

The exoplanet census now stands at 5,599 confirmed discoveries in 4,163 star systems, with another 10,157 candidates awaiting confirmation. So far, the vast majority of these have been detected using indirect methods, including Transit Photometry (74.4%) and Radial Velocity measurements (19.4%). Only nineteen (or 1.2%) were detected via Direct Imaging, a method where light emitted or reflected from an exoplanet’s atmosphere or surface is used to detect and characterize it. Thanks to the latest generation of high-contrast and high-angular resolution instruments, this is starting to change.

This includes the James Webb Space Telescope and its sophisticated mirrors and advanced infrared imaging suite. Using data obtained by Webb‘s Near-Infrared Camera (NIRCam), astronomers within the MIRI mid-INfrared Disk Survey (MINDS) survey recently studied a very young variable star (PDS 70) about 370 light-years away with two confirmed protoplanets. After examining the system and its extended protoplanetary disk, they found evidence of a third possible protoplanet orbiting the star. These observations could help advance our understanding of planetary systems that are still in the process of formation.

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Little Red Dots in Webb Photos Turned Out to Be Quasars

A n EIGER JWST image of the luminous quasar J1148+5251, an extremely rare active SMBH of 10 billion solar masses (blue box). Two “baby quasars” (red boxes) are seen in the same dataset. © NASA, ESA, CSA, J. Matthee (ISTA), R. Mackenzie (ETH Zurich), D. Kashino (National Observatory of Japan), S. Lilly (ETH Zurich)

In its first year of operation, the James Webb Space Telescope (JWST) made some profound discoveries. These included providing the sharpest views of iconic cosmic structures (like the Pillars of Creation), transmission spectra from exoplanet atmospheres, and breathtaking views of Jupiter, its largest moons, Saturn’s rings, its largest moon Titan, and Enceladus’ plumes. But Webb also made an unexpected find during its first year of observation that may prove to be a breakthrough: a series of little red dots in a tiny region of the night sky.

These little red dots were observed as part of Webb’s Emission-line galaxies and Intergalactic Gas in the Epoch of Reionization (EIGER) and the First Reionization Epoch Spectroscopically Complete Observations (FRESCO) surveys. According to a new analysis by an international team of astrophysicists, these dots are galactic nuclei containing the precursors of Supermassive Black Holes (SMBHs) that existed during the early Universe. The existence of these black holes shortly after the Big Bang could change our understanding of how the first SMBHs in our Universe formed.

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Now You Can See Exactly Where Hubble and JWST are Pointed

Graphics of the Hubble and James Webb Space Telescopes. Credit: NASA/STScI.

Hubble and JWST are busily scanning the sky, sending home enormous amounts of data. They shift from target to target, completing the required observations.

But have you ever wondered what those two space telescopes are doing right at this moment? Now, you can do just that at the new Space Telescope Live website. It will show you what each observatory is scanning, where the objects are in the sky, and what researchers hope to learn. You can even go back or forward in time and see what each telescope has been looking at in the past or what observations are coming up.

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New Webb Image of a Massive Star Forming Complex

This image from the NASA/ESA/CSA James Webb Space Telescope features an H II region in the Large Magellanic Cloud (LMC). Credit: NASA/ESA/CSA/M. Meixner

The James Webb Space Telescope, a collaborative effort between NASA, the ESA, and the Canadian Space Agency (CSA), has revealed some stunning new images of the Universe. These images have not only been the clearest and most details views of the cosmos; they’ve also led to new insight into cosmological phenomena. The latest image, acquired by Webb‘s Mid-InfraRed Instrument (MIRI), is of the star-forming nebula N79, located about 160,000 light-years away in the Large Magellanic Cloud (LMC). The image features a bright young star and the nebula’s glowing clouds of dust and gas from which new stars form.

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A Solo Brown Dwarf Found With Auroras

This artist concept portrays the brown dwarf W1935, which is located 47 light-years from Earth. Astronomers using NASA’s James Webb Space Telescope found infrared emission from methane coming from W1935, generating an aurora, a very unexpected discovery. Credit: NASA, ESA, CSA, Leah Hustak (STScI)

Astronomers have used JWST to find a brown dwarf with polar auroras like the Earth, or Jupiter. This is surprising because the brown dwarf, dubbed W1935, is a free-floating object, meaning it isn’t part of another star system. Therefore, there’s no solar wind available to generate any Northern Lights. Instead, the auroras are seemingly generated from methane emissions in the planet’s atmosphere, interacting with the interstellar plasma. Another theory is that it perhaps has an active but unseen moon contributing to the emissions.

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JWST and Chandra Team Up for a Stunning View of Supernova Remnant Cassiopeia A

This image of Cassiopeia A comes from a combination of data from the Chandra X-ray telescope and the James Webb Space Telescope. Credit: X-ray: NASA/CXC/SAO; Optical: NASA/ESA/STScI; IR: NASA/ESA/CSA/STScI/Milisavljevic et al., NASA/JPL/CalTech; Image Processing: NASA/CXC/SAO/J. Schmidt and K. Arcand

NASA’s long-lived Chandra X-ray Observatory teamed up with JWST for the first time, producing this incredibly detailed image of the famous supernova remnant Cassiopeia A. JWST first looked at the remnant in April 2023, and noticed an unusual debris structure from the destroyed star, dubbed the “Green Monster.” The combined view has helped astronomers better understand what this unusual structure is, plus it uncovered new details about the explosion that created Cas A.

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TRAPPIST-1c Isn’t the Exo-Venus We Were Hoping For. But Don’t Blame the Star

A recent study accepted to The Astrophysical Journal uses computer models to investigate why the exoplanet, TRAPPIST-1c, could not possess a thick carbon dioxide (CO2) atmosphere despite it receiving the same amount of solar radiation from its parent star as the planet Venus receives from our Sun, with the latter having a very thick carbon dioxide atmosphere. This study comes after a June 2023 study published in Nature used data from NASA’s James Webb Space Telescope (JWST) to ascertain that TRAPPIST-1c does not possess a carbon dioxide atmosphere. Both studies come as the TRAPPIST-1 system, which is located approximately 41 light-years from Earth and orbits its star in just 2.4 days, has received a lot of attention from the scientific community in the last few years due to the number of confirmed exoplanets within the system and their potential for astrobiology purposes.

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