Universe Today

September 28, 2023September 28, 2023 by Matt Williams

If Earth is Average, We Should Find Extraterrestrial Life Within 60 Light-Years

Astronomers have detected thousands of planets, including dozens that are potentially habitable. To winnow them down, they need to understand their atmospheres and other factors. (NASA Illustration)

In 1960, while preparing for the first meeting on the Search for Extraterrestrial Intelligence (SETI), legendary astronomer and SETI pioneer Dr. Frank Drake unveiled his probabilistic equation for estimating the number of possible civilizations in our galaxy – aka. The Drake Equation. A key parameter in this equation was n_e, the number of planets in our galaxy capable of supporting life – aka. “habitable.” At the time, astronomers were not yet certain other stars had systems of planets. But thanks to missions like Kepler, 5523 exoplanets have been confirmed, and another 9,867 await confirmation!

Based on this data, astronomers have produced various estimates for the number of habitable planets in our galaxy – at least 100 billion, according to one estimate! In a recent study, Professor Piero Madau introduced a mathematical framework for calculating the population of habitable planets within 100 parsecs (326 light-years) of our Sun. Assuming Earth and the Solar System are representative of the norm, Madau calculated that this volume of space could contain as much as 11,000 Earth-sized terrestrial (aka. rocky) exoplanets that orbit within their stars’ habitable zones (HZs).

September 27, 2023September 27, 2023 by Matt Williams

NASA Opens the Lid on OSIRIS-REx's Sample Capsule

OSIRIS REx Asteroid Sample Return lid opening at Building 31 Astromaterials Curation Facility at the Johnson Space Center. Credit: NASA/Robert Markowitz

On Sunday, September 23rd, the Sample Retrieval Capsule (SRC) from NASA’s OSIRIS-REx mission landed in the Utah desert. Shortly thereafter, recovery teams arrived in helicopters, inspected and secured the samples, and flew them to the Utah Test and Training Range (UTTR). On Monday, the sample canister was transferred to the Astromaterials Research and Exploration Science Directorate (ARES) in Houston, Texas. Yesterday, on Tuesday, September 26th, NASA announced that the process of unsealing and removing the samples from the canister had begun with the removal of the initial lid.

September 27, 2023September 27, 2023 by Evan Gough

How Do Lava Worlds Become Earth-Like, Living Planets?

This is an artist's illustration of Kepler-10 b, a suspected magma ocean planet about 560 light years away. Image Credit: NASA/Kepler Mission/Dana Berry

Earth was once entirely molten. Planetary scientists call this phase in a planet’s evolution a magma ocean, and Earth may have had more than one magma ocean phase. Earth cooled and, over 4.5 billion years, became the vibrant, life-supporting world it is today.

Can the same thing happen to exo-lava worlds? Can studying them shed light on Earth’s transition?

September 27, 2023September 27, 2023 by Evan Gough

Day Has Returned, but India’s Lander and Rover have Failed to Wake Up

The Pragyaan rover captured this image of the Vikram Lander on August 30th, before lunar night enshrouded it in its frigid darkness. Image Credit: ISRO.

It looks like India’s Chandrayaan-3 succumbed to the cold, and its mission is over. The frigid lunar night lasted about two weeks, and a new day has dawned. With that day came hopes of a sunlit revival for the lander and the rover, but the India Space Research Organization (ISRO) says the chances of the spacecraft awakening in the Sun are diminishing by the hour.

September 27, 2023September 27, 2023 by Evan Gough

Even Tiny Amounts of DNA on Mars Will Be Detectable

The Perseverance Mars rover took this selfie with several of the 10 sample tubes it deposited on the Image Credit: NASA/JPL-Caltech/MSSS.

The Search for Life is focused on the search for biosignatures. Planetary life leaves a chemical fingerprint on a planet’s atmosphere, and scientists are trying to work out which chemicals in what combinations and amounts are a surefire indicator of life. Martian methane is one they’re puzzling over right now.

But new evidence suggests that super-tiny amounts of DNA can be detected in Martian rocks if it’s there. And though it requires physical samples rather than remote sensing, it’s still an intriguing development.

September 27, 2023September 27, 2023 by Nancy Atkinson

It’s Official. No More Astronomy at Arecibo

Damage to the 305-meter telescope at Arecibo Observatory, after its collapse on Dec. 1, 2020. The remains of the instrument platform are visible on the telescope’s dish. Credit: NSF.

Even though the National Science Foundation announced last year that it would not rebuild or replace the iconic Arecibo radio dish in Puerto Rico — which collapsed in 2020 – a glimmer of hope remained among supporters that the remaining astronomy infrastructure would be utilized in some way.

Instead, the NSF announced this week they have chosen four institutions to transition the site from its historic hub of astronomical research to a STEM educational outreach center, with a seeming focus on biology. A biomedical laboratory, Cold Spring Harbor Laboratory in New York along with the University of Maryland, Baltimore County, and the University of Puerto Rico (UPR) and the University of the Sacred Heart, both in San Juan will oversee the new education center.

September 26, 2023September 26, 2023 by Evan Gough

Chinese Astronauts May Build a Base Inside a Lunar Lava Tube

Lava tubes are natural shelters and could serve as Moon bases. These images from the Lunar Reconaissance Orbiter show pits on the lunar surface. The images are each 222 meters (728 feet) wide. Credit: NASA/GSFC/Arizona State University

Caves were some of humanity’s first shelters. Who knows what our distant ancestors were thinking as they sought refuge there, huddling and cooking meat over a fire, maybe drawing animals on the walls. Caves protected our ancient ancestors from the elements, and from predators and rivals, back when sticks, stones, furs and fire were our only technologies.

So there’s a poetic parallel between early humans and us. We’re visiting the Moon again, and lunar caves could shelter us the way caves sheltered our ancestors on Earth.

September 25, 2023September 25, 2023 by Nancy Atkinson

Finally! Astronomers are Starting to See the First Galaxies Coming Together With JWST

The big galaxy in the foreground is named LEDA 2046648, and is seen just over a billion years back in time, while most of the others lie even farther away, and hence are seen even further back in time. CREDIT: ESA/Webb, NASA & CSA, A. Martel.

One of the James Webb Space Telescope’s principal science goals is to observe the epoch where we think that the first galaxies were created, to understand the details of their formation, evolution, and composition. With each deep look back in time, the telescope seems to break its own record for the most distant galaxy ever seen. Science papers are now are starting to trickle in, as astronomers are finally starting to collect enough data from JWST to build a deeper understanding of the early Universe.

In a new study published in Nature Astronomy, a team of researchers in Denmark believe they have observed some of the very first, earliest galaxies with JWST. These galaxies are so old, they are likely still in the process of being formed.

September 25, 2023September 25, 2023 by Evan Gough

Gaia is Now Finding Planets. Could it Find Another Earth?

Artist's impression of the ESA's Gaia Observatory. Credit: ESA

The ESA launched Gaia in 2013 with one overarching goal: to map more than one billion stars in the Milky Way. Its vast collection of data is frequently used in published research. Gaia is an ambitious mission, though it seldom makes headlines on its own.

But that could change.

September 25, 2023September 26, 2023 by Matt Williams

Why Build Megastructures? Just Move Planets Around to Make Habitable Worlds

An artist view of countless exoplanets. Credit: NASA/JPL-Caltech

In 1960, Freeman Dyson proposed how advanced civilizations could create megastructures that enclosed their star, allowing them to harness all of their star’s energy and multiplying the habitable space they could occupy. In 2015, the astronomical community was intrigued when the star KIC 8462852 (aka. Tabby’s Star) began experiencing unexplained changes in brightness, leading some to speculate that the variations might be due to a megastructure. While the final analysis of the star’s light curve in 2018 revealed that the dimming pattern was more characteristic of dust than a solid structure, Tabby’s Star focused attention on the subject of megastructures and their associated technosignatures.

Dyson’s ideas were proposed at a time when astronomers were unaware of the abundance of exoplanets in our galaxy. The first confirmed exoplanet was not discovered until 1992, and that number has now reached 5,514! With this in mind, a team of researchers from Bangalore, India, recently released a paper that presents an alternative to the whole megastructure concept. For advanced civilizations looking for more room to expand, taking planets within their system – or capturing free-floating planets (FFP) beyond – and transferring them into the star’s circumsolar habitable zone (HZ) is a much simpler and less destructive solution.