Future Space Telescopes Could be Made From Thin Membranes, Unrolled in Space to Enormous Size

Illustration of an array of membrane mirror telescopes. Credit: Sebastian Rabien, Max Planck Institute for Extraterrestrial Physics

Space-based telescopes are remarkable. Their view isn’t obscured by the weather in our atmosphere, and so they can capture incredibly detailed images of the heavens. Unfortunately, they are quite limited in mirror size. As amazing as the James Webb Space Telescope is, its primary mirror is only 6.5 meters in diameter. Even then, the mirror had to have foldable components to fit into the launch rocket. In contrast, the Extremely Large Telescope currently under construction in northern Chile will have a mirror more than 39 meters across. If only we could launch such a large mirror into space! A new study looks at how that might be done.

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Webb Confirms a Longstanding Galaxy Model

JWST image of the grand design spiral galaxy NGC 628. Credit: NASA / ESA / CSA / Judy Schmidt (CC BY 2.0)

Perhaps the greatest tool astronomers have is the ability to look backward in time. Since starlight takes time to reach us, astronomers can observe the history of the cosmos by capturing the light of distant galaxies. This is why observatories such as the James Webb Space Telescope (JWST) are so useful. With it, we can study in detail how galaxies formed and evolved. We are now at the point where our observations allow us to confirm long-standing galactic models, as a recent study shows.

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Will Advanced Civilizations Build Habitable Planets or Dyson Spheres

Artist's impression of the terraforming of Mars, from its current state to a livable world. Credit: Daein Ballard
Artist's impression of the terraforming of Mars, from its current state to a livable world. Credit: Daein Ballard

If there are alien civilizations in the Universe, some of them could be super advanced. So advanced that they can rip apart planets and create vast shells surrounding a star to capture all its energy. These Dyson spheres should be detectable by modern telescopes. Occasionally astronomers find an object that resembles such an alien megastructure, but so far, they’ve all turned out to be natural objects. As best we can tell, there are no Dyson spheres out there.

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Learning More About Supernovae Through Stardust

Illustration of Supernova 1987A based on observations by ALMA. Credit: Alexandra Angelich (NRAO/AUI/NSF)

Most of the diverse elements in the Universe come from supernovae. We are, quite literally, made of the dust of those long-dead stars and other astrophysical processes. But the details of how it all comes about are something astronomers strive to understand. How do the various isotopes produced by supernovae drive the evolution of planetary systems? Of the various types of supernovae, which play the largest role in creating the elemental abundances we see today? One way astronomers can study these questions is to look at presolar grains.

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Astronomers Predict the Orbits of Potentially Hazardous Comets From Meteor Showers

Comet
Views of several comets over the centuries, including Halley's Comet. Credit: Astronomy/1860 Engraving/Wellcome Collection/Public Domain

Comets have long been seen as omens and portents, and it’s easy to understand why. They first appear as faint smudges of light in the sky, sometimes fading soon after and sometimes becoming brighter than the planets, with a long, glowing tail. They have been observed throughout human history, but it wasn’t until the eighteenth century that astronomers began to predict the return of some comets. Even today, we can’t predict the return of most comets until after they swing through the inner solar system. If such a comet happens to be heading toward Earth, we wouldn’t know about it until too late. But that could change thanks to our observations of meteor showers.

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Astronomers Have Found the Fastest Spinning Neutron Star

Illustration of a millisecond pulsar consuming material from a companion star. Pulsars that evaporate their companions rather than consuming them could serve as stellar engines. Credit: NASA / GSFC SVS / Dana Berry

Neutron stars are as dense as the nucleus of an atom. They contain a star’s worth of matter in a sphere only a dozen kilometers wide. And they are light-years away. So how can we possibly understand their interior structure? One way would be to simply spin it. Just spin it faster and faster until it reaches a maximum limit. That limit can tell us about how neutron stars hold together and even how they might form. Obviously, we can’t actually spin up a neutron star, but it can happen naturally, which is one of the reasons astronomers are interested in these maximally spinning stars. And recently a team has discovered a new one.

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Could Life at TRAPPIST-1 Survive the Star's Superflares?

Artist's Illustration of a Young Red Dwarf Stripping Away a Planet's Atmosphere. Credit: NASA, ESA, and D. Player (STScI)

The TRAPPIST-1 system is a science-fiction writer’s dream. Seven Earth-sized worlds orbit a red dwarf star just 40 light-years away. Three of those worlds are within the habitable zone of the star. The system spans a distance less than 25 times that of the distance from the Earth to the Moon. Oh, what epic tales a TRAPPIST civilization would have! That is, if life in such a system is even possible…

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Here are Some Potentially Habitable World Targets for the Upcoming LIFE Mission

LIFE will have five separate space telescopes that fly in formation and work together to detect biosignatures in exoplanet atmospheres. Image Credit: LIFE, ETH Zurich

The odds are good that we are not alone in the Universe. We have found thousands of exoplanets so far, and there are likely billions of potentially habitable planets in our galaxy alone. But finding evidence of extraterrestrial life is challenging, and even the most powerful telescopes we currently have may not produce definitive proof. But there are telescopes in the pipeline that may uncover life. It will be decades before they are built and launched, but when they are, which systems should they target first? That’s the question answered in a recent paper.

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The First Triple Star System Found Containing a Black Hole

V404 Cygni in the process of consuming a nearby star while a second star orbits at a distance. Credit: Jorge Lugo

Neutron stars and black holes are the remnants of dead stars. They typically form as part of a supernova explosion, where the outer layers of an old star are violently cast off while the core of the star collapses to form the remnant. This violent origin can have significant consequences for both the remnant and the surrounding environment.

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There's a Particle Accelerator at the Center of the Milky Way

Gamma ray emissions in the center of the Milky Way. Credit: Albert, et al

Nestled on the slopes of Cerro La Negra at an elevation of 13,000 feet is an unusual-looking observatory. Known as the High-Altitude Water Cherenkov (HAWC) observatory, it looks like a tightly packed collection of grain silos, which is essentially what it is. But rather than holding grain, the silos are each filled with 188,000 liters of water and four photomultiplier tubes. While it’s an unusual setup, it’s what you need to observe high-energy gamma rays from deep space.

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