The Next Generation LIFE Telescope Could Detect Some Intriguing Biosignatures

Artist's impression of the proposed LIFE mission. Credit: LIFE Initiative / ETH Zurich

The Large Interferometer for Exoplanets (LIFE) project is an ambitious plan to build a space telescope with four independent mirrors. The array would allow the individual mirrors to move closer or farther apart, similar to the way the Very Large Array (VLA) does with radio antennas. LIFE is still early in its planning stage, so it would likely be decades before it is built, but already the LIFE team is looking at ways it might discover life on other worlds. Much of this focuses on the detection of biogenic molecules in exoplanet atmospheres.

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Life on Earth Uses Water as a Solvent. What are Some Other Options for Life as We Don't Know it?

A near-infrared view of Titan showing its glinting seas. Credit: NASA/JPL-Caltech/University of Arizona/University of Idaho

There is a vast menagerie of potentially habitable worlds in the cosmos, which means the Universe could be home to a diversity of life beyond what we can imagine. Creatures built on silicon rather than carbon, or organisms that breathe hydrogen instead of oxygen. But regardless of how strange and wondrous alien life may be, it is still governed by the same chemistry as life on Earth, and that means it needs a chemical solvent.

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M87*'s Event Horizon Image. One Year Later

The elliptical galaxy M87 seen by various telescopes. Credit: NASA's Scientific Visualization Studio/M.SubbaRao & NASA/CXC/SAO/A.Jubett

Fifty-five million light years from Earth there is a massive elliptical galaxy known as Messier 87, or M87 for short. It was cataloged by Charles Messier in the 1700s, along with 102 other fuzzy objects in the sky that were definitely not comets. It was confirmed to be a galaxy in the early 1900s, and by the mid-twentieth century, it was known to be a powerful radio source. But these days it is most widely known for the supermassive black hole deep in its core. Called M87*, it is the first black hole directly observed by astronomers. The first image of M87* was released in 2019, and was based on observations taken by the Event Horizon Telescope (EHT) in 2017. Now a new image based on 2018 data has been released. The similarities and differences between the two images tell us a great deal about M87* and black holes in general.

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Astronomers Have Mapped the Milky Way's Magnetic Fields in 3D

Magnetic fields mapped within the Whirlpool Galaxy. Credit: NASA, SOFIA science team, ESA, STScI

Our galaxy is filled with magnetic fields. They come not just from stars and planets, but from dusty stellar nurseries and the diffuse hydrogen gas of interstellar space. We’ve long known of this galactic magnetic field, but mapping it in detail has posed a challenge. Now a new study gives us a detailed 3-dimensional map of these fields, with a few surprises.

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Astronomers Rule Out One Explanation for the Hubble Tension

One of the brightest Cepheid variable stars, RS Puppis. Credit: NASA, ESA, and the Hubble Heritage Team (STScI/AURA)-Hubble/Europe Collaboration

Perhaps the greatest and most frustrating mystery in cosmology is the Hubble tension problem. Put simply, all the observational evidence we have points to a Universe that began in a hot, dense state, and then expanded at an ever-increasing rate to become the Universe we see today. Every measurement of that expansion agrees with this, but where they don’t agree is on what that rate exactly is. We can measure expansion in lots of different ways, and while they are in the same general ballpark, their uncertainties are so small now that they don’t overlap. There is no value for the Hubble parameter that falls within the uncertainty of all measurements, hence the problem.

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Gigantic Galaxy Clusters Found Just Before They're Awash in Star Formation

This panchromatic view of galaxy cluster MACS0416 was created by combining infrared observations from the NASA/ESA/CSA James Webb Space Telescope with visible-light data from the NASA/ESA Hubble Space Telescope. Credit: NASA/ESA/CSA/STScI

One of the central factors in the evolution of galaxies is the rate at which stars form. Some galaxies are in a period of active star formation, while others have very little new stars. Very broadly, it’s thought that younger galaxies enter a period of rapid star formation before leveling off to become a mature galaxy. But a new study finds some interesting things about just when and why stars form.

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Dark Matter Could Map the Universe's Early Magnetic Fields

Illustration of magnetic field lines running between galaxies. Credit: Chris Mihos/ CWRU

We think of magnetic fields as a part of planets and stars. The Earth and Sun have relatively strong magnetic fields, as do more exotic objects such as neutron stars and the accretion disks of black holes. But magnetic field lines also run throughout galaxies, and even between the vast voids of intergalactic space. Magnetic fields are quite literally everywhere, and we aren’t entirely sure why. One idea is that faint magnetic fields formed during the earliest moments of the Universe. If that’s the case, we might be able to prove it through the distribution of dark matter.

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Multiple Supernova Remnants Merging in a Distant Nebula

The nebula 30 Doradus B seen in x-ray, optical, and visible light. Credit: X-ray: NASA/CXC/Penn State Univ./L. Townsley et al.; Optical: NASA/STScI/HST; Infrared: NASA/JPL/CalTech/SST; Image Processing: NASA/CXC/SAO/J. Schmidt, N. Wolk, K. Arcand

The key to astronomy is careful observation. Unlike many sciences, astronomers can’t often do their work in a lab. Sure, they can build space telescopes and large ground observatories, but even with tools as simple as sticks and stones astronomers were able to change our understanding of the Universe with patience and observation. That tradition still holds true today, as a recent study in The Astronomical Journal shows.

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Do Neutron Stars Have Mountains? Gravitational Wave Observatories Could Detect Them

Light bursts from the collision of two neutron stars. Credit: NASA's Goddard Space Flight Center/CI Lab

The surface gravity of a neutron star is so incredibly intense that it can cause atoms to collapse into a dense cluster of neutrons. The interiors of neutron stars may be dense enough to allow quarks to escape the bounds of nuclei. So it’s hard to imagine neutron stars as active bodies, with tectonic crusts and perhaps even mountains. But we have evidence to support this idea, and we could learn even more through gravitational waves.

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Want to Find Life? See What's Missing in an Atmosphere

Illustration potentially habitable worlds. Credit: Christine Daniloff, MIT; iStock

The world runs on carbon. Not just fossil-fuel-driven human society, but all life on Earth. Carbon-based organic molecules are a part of every living thing on Earth. Along with oxygen, nitrogen, and water, carbon is a necessary ingredient for life as we know it. So one way to look for life on other worlds could be to look for carbon in its atmosphere. But a new study shows that it’s actually a lack of carbon that could be the best clue to life on another world.

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