SETI Works Best When Telescopes Double-Check Each Other

The LOFAR 'superterp', part of the core of the extended telescope located in the Netherlands. Credit: LOFAR/ASTRON

The Search for Extraterrestrial Intelligence (SETI) has evolved considerably in the past sixty years since the first experiment was conducted. This was Project Ozma, which was conducted in 1960 by Dr. Frank Drake and his colleagues using the National Radio Astronomy Observatory (NRAO) in Green Bank, West Virginia. While the experiment did not reveal any radio signals from space, it established the foundation upon which all future SETI is based. Like Ozma, the vast majority of these experiments have searched for possible technosignatures in the radio spectrum.

Unfortunately, this search has always been plagued by the problem of radio interference from Earth-based radio antennas and satellites in orbit, which can potentially flood SETI surveys with false positives. In a recent study, an international team of astronomers (including researchers with Breakthrough Listen) recommended that future technosignature searches rely on multi-site simultaneous observations. This has the potential of eliminating interference from terrestrial sources and narrowing the search for extraterrestrial radio signals.

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Earth is Hiding Another Planet Deep Inside

During an ancient collision, the protoplanet named Theia slammed into Earth, leading to the creation of the Moon. But it left some of its remains inside Earth. Image Credit: CalTech

Earth’s early history is marked by massive collisions with other objects, including planetesimals. One of the defining events in our planet’s history, the formation of the Moon, likely resulted from one of these catastrophic collisions when a Mars-sized protoplanet crashed into Earth. That’s the Giant Impact Hypothesis, and it explains how the collision produced a torus of debris rotating around the Earth that eventually coalesced into our only natural satellite.

New research strengthens the idea that Theia left some of its remains inside Earth.

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Lucy Completes its First Flyby… and Discovers a Bonus Asteroid

Dinkinesh
Moonlet rise over Dinkinesh as seen from NASA's Lucy spacecraft, taken within a minute of closest approach. Credit: NASA/Goddard/SwRI/Johns Hopkins APL/NOAO

NASA’s Lucy mission hits the jackpot on its very first asteroid flyby earlier this week.

Welcome to Dinkinesh. NASA’s Lucy mission flew past its first target of Wednesday, November 1st, and turned up a surprise: 152830 Dinkinesh (meaning ‘marvelous’ in the Amharic language) is not one asteroid, but two (!)

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ESA’s Hera Mission is Bringing Two Cubesats Along. They’ll Be Landing on Dimorphos

This illustration shows the ESA's Hera spacecraft and its two CubeSats at the binary asteroid Didymos. Image Credit: ESA

In about one year from now, the European Space Agency will launch its Hera mission. Its destination is the asteroid Didymos, and it’ll be the second human spacecraft to visit the 390-meter chunk of rock. NASA’s DART mission crashed a kinetic impactor into Didymos’ tiny moonlet Dimorphos as a test of planetary defence.

Hera will perform a follow-up investigation of the binary asteroid to measure the size and morphology of the impact crater on Dimorphos. To help it along, it’s taking two tiny CubeSats that will land on Dimorphos.

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Jupiter Looks Bizarre in Hubble's New Ultraviolet Image

NASA's Hubble Space Telescope reveals an ultraviolet view of Jupiter. NASA, ESA, and M. Wong (University of California - Berkeley); Processing: Gladys Kober (NASA/Catholic University of America)

Jupiter has gone pastel!

Check out this ultra-cool image of Jupiter taken by the Hubble Space Telescope. This is a color composite picture of Jupiter seen in ultraviolet, which reveals different features in Jupiter’s atmosphere. One feature that stands out is Jupiter’s Great Red Spot — it is blue in this image!

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Old Data from Kepler Turns Up A System with Seven Planets

Artist’s concept of Kepler-385, the seven-planet system revealed in a new catalog of planet candidates discovered by NASA’s Kepler space telescope. Image Credit: NASA/Daniel Rutter

NASA’s Kepler mission ended in 2018 after more than nine years of fruitful planet-hunting. The space telescope discovered thousands of planets, many of which bear its name. But it also generated an enormous amount of data that exoplanet scientists are still analyzing.

Now, a team of researchers has shed new light on a seven-planet system in Kepler’s ocean of data.

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Comet H2 Lemmon Brightens in Early November Ahead of Expectations

Comet H2 Lemmon
Comet H2 Lemmon passes near the galaxy NGC 4258 on October 12th. Credit: Dan Bartlett

Discovered early this year, Comet C/2023 H2 Lemmon may approach naked eye brightness this month.

A comet discovered earlier this year is performing above expectations, and is currently well-placed in the dusk sky. We’re talking about Comet C/2023 H2 Lemmon, moving up the charts now at magnitude +8 and brightening.

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A Dwarf Galaxy That's Almost All Dark Matter

A simulation of dark matter clusters around the Milky Way. Credit: J. Tumlinson (STScI)

Dark matter is a powerful cosmological model, but it isn’t without its problems. In addition to our inability to detect dark matter particles, one issue deals with the number of dwarf galaxies surrounding the Milky Way. According to the most popular models of dark matter, galaxies should be surrounded by clumps of dark matter within their dark matter halo. Since regular matter tends to gather around dark matter, that means the Milky Way should be surrounded by dwarf galaxies. While there are several known dwarf galaxies near the Milky Way, there are fewer than predicted by dark matter simulations. But perhaps there are many more dwarf galaxies we just haven’t noticed because they are made mostly of dark matter.

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Devastating Clouds of Dust Helped End the Reign of the Dinosaurs

Paleoart reconstruction depicting North Dakota in the first months following the Chicxulub impact event 66 million years ago, showing a dark, dusty, and cold world in which the last non-avian dinosaurs, illustrated with a Dakotaraptor steini, were on the edge of extinction. Artwork by Mark A. Garlick.

When a giant meteor crashed into Earth 66 million years ago, the impact pulverized cubic kilometers of rock and blasted the dust and debris into the Earth’s atmosphere. It was previously believed that sulfur from the impact and soot from the global fires that followed drove a global “impact winter” that killed off 75% of species on Earth, including the dinosaurs.

A new geology paper says that the die-off was additionally fueled by ultrafine dust created by the impact which filled the atmosphere and blocked sunlight for as long as 15 years. Plants were unable to photosynthesize and global temperatures were lowered by 15 degrees C (59 F).

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A Collapsed Martian Lava Chamber, Seen From Space

This HiRise image of Hephaestus Fossae shows a volcanic area that's collapsed into a pit. We should explore it. Image Credit: NASA/JPL-Caltech/UArizona

Lava tubes and chambers attract a lot of attention as potential sites for bases on the Moon and Mars. They provide protection from radiation, from temperature swings, and even from meteorites. They beg to be explored.

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