The World's Largest Radio Telescope Just Scanned 33 Exoplanets for a Signal From Aliens

The Five-hundred-metre Aperture Spherical Telescope (FAST) has just finished construction in the southwestern province of Guizhou. Credit: FAST

The Five-hundred-meter Aperture Spherical Telescope (FAST), located in China, is currently the world’s largest and most sophisticated radio observatory. While its primary purpose is to conduct large-scale neutral hydrogen surveys (the most common element in the Universe), study pulsars, and detect Fast Radio Bursts (FRBs), scientists have planned to use the array in the Search for Extraterrestrial Intelligence (SETI). Integral to this field of study is the search for technosignatures, signs of technological activity that indicate the presence of an advanced civilization.

While many potential technosignatures have been proposed since the first surveys began in the 1960s, radio transmissions are still considered the most likely and remain the most studied. In a recent survey, an international team of SETI researchers conducted a targeted search of 33 exoplanet systems using a new method they call the “MBCM blind search mode.” While the team detected two “special signals” using this mode, they dismissed the idea that they were transmissions from an advanced species. Nevertheless, their survey demonstrated the effectiveness of this new blind mode and could lead to plausible candidate signals in the future.

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Astronomers are Working on a 3D map of Cosmic Dawn

The HERA radio telescope consists of 350 dishes pointed upward to detect 21-centimeter emissions from the early Universe. Credit: HERA Partnership

The frontiers of astronomy are being pushed regularly these days thanks to next-generation telescopes and scientific collaborations. Even so, astronomers are still waiting to peel back the veil of the cosmic “Dark Ages,” which lasted from roughly 370,000 to 1 billion years after the Big Bang, where the Universe was shrouded with light-obscuring neutral hydrogen. The first stars and galaxies formed during this same period (ca. 100 to 500 million years), slowly dispelling the “darkness.” This period is known as the Epoch of Reionization, or as many astronomers call it: Cosmic Dawn.

By probing this period with advanced radio telescopes, astronomers will gain valuable insights into how the first galaxies formed and evolved. This is the purpose of the Hydrogen Epoch of Reionization Array (HERA), a radio telescope dedicated to observing the large-scale structure of the cosmos during and before the Epoch of Reionization located in the Karoo desert in South Africa. In a recent paper, the HERA Collaboration reports how it doubled the array’s sensitivity and how their observations will lead to the first 3D map of Cosmic Dawn.

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Astronomers Prepare to Launch LuSEE Night, A Test Observatory on the Far Side of the Moon

Artist's illustration of a radio telescope inside a crater on the Moon. Credit: NASA JPL

Astronomers have not yet been able to map large portions of the radio emissions from our universe because of interference from the Earth itself. A team of astronomers hopes to change that, beginning with the LuSEE Night mission to the far side of the Moon. It will launch in 2025 and chart a new pathway to Lunar observatories.

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Astronomers Find 25 Fast Radio Bursts That Repeat on a Regular Basis

CHIME consists of four metal "half-pipes", each one 100 meters long. Image Credit: CHIME/Andre Renard, Dunlap Institute.
CHIME consists of four metal "half-pipes", each one 100 meters long. Image Credit: CHIME/Andre Renard, Dunlap Institute.

Like Gravitational Waves (GWs) and Gamma-Ray Bursts (GRBs), Fast Radio Bursts (FRBs) are one of the most powerful and mysterious astronomical phenomena today. These transient events consist of bursts that put out more energy in a millisecond than the Sun does in three days. While most bursts last mere milliseconds, there have been rare cases where FRBs were found repeating. While astronomers are still unsure what causes them and opinions vary, dedicated observatories and international collaborations have dramatically increased the number of events available for study.

A leading observatory is the Canadian Hydrogen Intensity Mapping Experiment (CHIME), a next-generation radio telescope located at the Dominion Radio Astrophysical Observatory (DRAO) in British Columbia, Canada. Thanks to its large field of view and broad frequency coverage, this telescope is an indispensable tool for detecting FRBs (more than 1000 sources to date!) Using a new type of algorithm, the CHIME/FRB Collaboration found evidence of 25 new repeating FRBs in CHIME data that were detected between 2019 and 2021.

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Astronomers use the World's Biggest Radio Telescope to map new Features of the Milky Way

Artist impression of a fast radio burst. Credit: Danielle Futselaar
Artist impression of a fast radio burst. Credit: Danielle Futselaar

Despite everything astronomers have learned about the nature and structure of galaxies, there are still mysteries about the Milky Way. The reason for this is simple: since we are embedded in the Milky Way’s disk, we have difficulty mapping it and observing it as a whole. It’s also very challenging to observe the center of the galaxy, what lies beyond it, and features in the disk itself because of all the gas and dust between stars- the Interstellar Medium (ISM). However, by observing the Milky Way in the non-visible spectrum (radio, x-ray, gamma-ray, etc.), astronomers can see more of what’s out there.

There’s also the spectral line that corresponds to the emission frequency (1420 MHz) of cold neutral hydrogen gas (HI), which makes up the majority of the ISM. Using the Five-hundred-meter Aperture Spherical Telescope (FAST) – the most powerful radio telescope in the world near Guizhou, China – a team of scientists located more than 500 new faint pulsars. During the survey, the team simultaneously recorded the spectral line data with high spectral and spatial resolution, making it an extremely valuable resource for studying the structure of the Milky Way Galaxy and the life cycle of its stars.

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Just Four Robots Could Deploy a Huge Radio Telescope on the Far Side of the Moon

FARSIDE Concept: Rendering that shows the initial stages of tethered-rover egress from a parent lander. Credit: XP4D, NASA JPL, and Blue Origin

For decades, astronomers have advocated building radio telescopes on the far side of the Moon. This “radio-quiet” zone always faces away from Earth and would provide the perfect location to study a variety of astronomical phenomena that can’t be observed in low radio frequencies from our planet, or even by Earth-orbiting space telescopes. But the costs and logistics of such a project have pushed most of these concepts to the realm of futuristic dreams.

But now a group of astronomers and engineers have worked out a concept for a radio telescope placed on the lunar far side that could be as large as 100 square kilometers across, and it could be deployed from a robotic lunar lander and four two-wheeled rovers. 

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Too Many Supernovae Can Slow Star Formation in a Galaxy

star formation regions in M33 are disrupted by cosmic-ray driven winds
Artist's illustration of cosmic ray-driven winds (blue and green) superimposed on a visible-light image of the Triangulum galaxy M33 (red and white) observed with VLT Survey Telescope at ESO’s Paranal Observatory in Chile. Credit: Institute for Research in Fundamental Sciences- IPM & European Southern Observatory (ESO)

Interstellar winds are powerful agents of change. For one thing, they can interrupt or shut down the process of star birth completely. That’s what a team of astronomers using the Karl Jansky Very Large Array in New Mexico found when they studied the galaxy M33. They also learned that speedy cosmic rays play a huge role in pushing those winds across interstellar space.

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A Black Hole Burps out Material, Years After Feasting on a Star

. Credit: DESY/Science Communication Lab

Originally predicted by Einstein’s Theory of General Relativity, black holes are the most extreme object in the known Universe. These objects form when stars reach the end of their life cycle, blow off their outer layers, and are so gravitationally powerful that nothing (not even light) can escape their surfaces. They are also of interest because they allow astronomers to observe the laws of physics under the most extreme conditions. Periodically, these gravitational behemoths will devoir stars and other objects in their vicinity, releasing tremendous amounts of light and radiation.

In October 2018, astronomers witnessed one such event when observing a black hole in a galaxy located 665 million light-years from Earth. While astronomers have witnessed events like this before, another team from the Harvard & Smithsonian Center for Astrophysics noticed something unprecedented when they examined the same black hole three years later. As they explained in a recent study, the black hole was shining very brightly because it was ejecting (or “burping”) leftover material from the star at half the speed of light. Their findings could provide new clues about how black holes feed and grow over time.

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Construction Begins on the World’s Largest Steerable Radio Telescope

Radio astronomy has been in flux lately. With the permanent loss of the Arecibo telescope in Puerto Rico, a new global power has taken center stage in humanity’s search for radio signals – China. Recently the Chinese announced the start of work on a new milestone telescope, which will eventually make it the biggest moveable one in the world.

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Alien Artifacts Could Be Hidden Across the Solar System. Here’s how we Could Search for Them.

Galileo Project members (from left: Carson Ezell, Ezra Kelderman, Abby White, Alex and Lily Delacroix) with the audio tower (left), radar spectrum tower (middle) and radar imaging tower (right) behind them on the roof of the Harvard College Observatory.
Galileo Project members (from left: Carson Ezell, Ezra Kelderman, Abby White, Alex and Lily Delacroix) with the audio tower (left), radar spectrum tower (middle) and radar imaging tower (right) behind them on the roof of the Harvard College Observatory. Image credit: The Galileo Project

Do aliens exist? Almost certainly. The universe is vast and ancient, and our corner of it is not particularly special. If life emerged here, it probably did elsewhere. Keep in mind this is a super broad assumption. A single instance of fossilized archaebacteria-like organisms five superclusters away would be all it takes to say, “Yes, there are aliens!” …if we could find them somehow.

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