Universe Today

April 23, 2024April 23, 2024 by Nancy Atkinson

Purple Bacteria — Not Green Plants — Might Be the Strongest Indication of Life

Artist's impression of Earth in the early Archean with a purplish hydrosphere and coastal regions. Even in this early period, life flourished and was gaining complexity. Credit: Oleg Kuznetsov — Artist's impression of Earth in the early Archean with a purplish hydrosphere and coastal regions. Even in this early period, life flourished and was gaining complexity, and distant exoplanets might begin similarly. Credit: Oleg Kuznetsov

Astrobiologists continue to work towards determining which biosignatures might be best to look for when searching for life on other worlds. The most common idea has been to search for evidence of plants that use the green pigment chlorophyll, like we have on Earth. However, a new paper suggests that bacteria with purple pigments could flourish under a broader range of environments than their green cousins. That means current and next-generation telescopes should be looking for the emissions of purple lifeforms.

“Purple bacteria can thrive under a wide range of conditions, making it one of the primary contenders for life that could dominate a variety of worlds,” said Lígia Fonseca Coelho, a postdoctoral associate at the Carl Sagan Institute (CSI) and first author of “Purple is the New Green: Biopigments and Spectra of Earth-like Purple Worlds,” published in the Monthly Notices of the Royal Astronomical Society: Letters.

April 23, 2024April 23, 2024 by Evan Gough

See the Southern Ring Nebula in 3D

The Southern Ring Nebula, or NGC 3132, was one of the first objects observed by the James Webb Space Telescope. Astronomers are digging more deeply into the nebula with additional observatories to expand their understanding of the structure. Image Credit: NASA/ESA/CSA/STScI

Planetary nebula are some of nature’s most stunning visual displays. The name is confusing since they’re the remains of stars, not planets. But that doesn’t detract from their status as objects of captivating beauty and intense scientific study.

April 23, 2024April 23, 2024 by Matt Williams

Hubble Has Accidentally Discovered Over a Thousand Asteroids

Illustration of Asteroid (Artist’s Impression). Credit: N. Bartmann (ESA/Webb), ESO/M. Kornmesser and S. Brunier, N. Risinger

The venerable Hubble Space Telescope is like a gift that keeps on giving. Not only is it still making astronomical discoveries after more than thirty years in operation. It is also making discoveries by accident! Thanks to an international team of citizen scientists, with the help of astronomers from the European Space Agency (ESA) and some machine learning algorithms, a new sample of over one thousand asteroids has been identified in Hubble‘s archival data. The methods used represent a new approach for finding objects in decades-old data that could be applied to other datasets as well.

April 22, 2024April 22, 2024 by Carolyn Collins Petersen

NASA Restores Communications with Voyager 1

An artist's concept of Voyager 1 in interstellar space. Courtesy: NASA.

The venerable Voyager 1 spacecraft is finally phoning home again. This is much to the relief of mission engineers, scientists, and Voyager fans around the world.

April 22, 2024April 22, 2024 by Matt Williams

Will We Know if TRAPPIST-1e has Life?

Artist's impression of the Archean Eon. Credit: Tim Bertelink/Wikimedia

The search for extrasolar planets is currently undergoing a seismic shift. With the deployment of the Kepler Space Telescope and the Transiting Exoplanet Survey Satellite (TESS), scientists discovered thousands of exoplanets, most of which were detected and confirmed using indirect methods. But in more recent years, and with the launch of the James Webb Space Telescope (JWST), the field has been transitioning toward one of characterization. In this process, scientists rely on emission spectra from exoplanet atmospheres to search for the chemical signatures we associate with life (biosignatures).

However, there’s some controversy regarding the kinds of signatures scientists should look for. Essentially, astrobiology uses life on Earth as a template when searching for indications of extraterrestrial life, much like how exoplanet hunters use Earth as a standard for measuring “habitability.” But as many scientists have pointed out, life on Earth and its natural environment have evolved considerably over time. In a recent paper, an international team demonstrated how astrobiologists could look for life on TRAPPIST-1e based on what existed on Earth billions of years ago.

April 22, 2024April 22, 2024 by Mark Thompson

Astronaut Food Will Lose Nutrients on Long-Duration Missions. NASA is Working on a Fix

NASA astronaut and Expedition 68 Flight Engineer Nicole Mann works in the International Space Station’s Harmony module on the BioNutrients-2 investigation that uses genetically engineered microbes to provide nutrients, and potentially other compounds and pharmaceuticals, on demand in space. NASA

Astronauts on board the International Space Station are often visited by supply ships from Earth with food among other things. Take a trip to Mars or other and the distances are much greater making it impractical to send fresh supplies. The prepackaged food used by NASA loses nutritional value over time so NASA is looking at ways astronauts can produce nutrients. They are exploring genetic engineering techniques that can create microbes with minimal resource usage.

April 22, 2024April 22, 2024 by David Dickinson

There Was a Doomed Comet Near the Sun During the Eclipse

A surprise appearance of a new comet made the April 8^th total solar eclipse all the more memorable.

Any dedicated ‘umbraphile’ will tell you: no two eclipses are exactly the same. Weather, solar activity, and the just plain expeditionary nature of reaching and standing in the shadow of the Moon for those brief moments during totality assures a unique experience, every time out. The same can be said for catching a brief glimpse of what’s going on near the Sun, from prominences and the pearly white corona to the configuration of bright planets… and just maybe, a new comet.

April 21, 2024April 21, 2024 by Mark Thompson

The Ingenuity Team Downloads the Final Data from the Mars Helicopter. The Mission is Over

I really can’t believe that the Ingenuity helicopter on Mars took its maiden voyage in April 2021. On the 16th April 2024, engineers at NASA have received the final batch of data from the craft which marks the final task of the team. Ingenuity’s work is not over though as it will remain on the surface collecting data. For the engineers at NASA, they have their sights set on Dragonfly, a new helicopter destined for Titan.

April 20, 2024April 20, 2024 by Nancy Atkinson

Juno Reveals a Giant Lava Lake on Io

An artists rendition of Loki Patera, a lava lake on Jupiter’s moon Io. Credit: NASA.

NASA’s Juno spacecraft came within 1,500 km (930 miles) of the surface of Jupiter’s moon Io in two recent flybys. That’s close enough to reveal new details on the surface of this moon, the most volcanic object in the Solar System. Not only did Juno capture volcanic activity, but scientists were also able to create a visual animation from the data that shows what Io’s 200-km-long lava lake Loki Patera would look like if you could get even closer. There are islands at the center of a magma lake rimmed with hot lava. The lake’s surface is smooth as glass, like obsidian.

April 20, 2024April 20, 2024 by Mark Thompson

What’s the Most Effective Way to Explore our Nearest Stars?

Project Starshot, an initiative sponsored by the Breakthrough Foundation, is intended to be humanity's first interstellar voyage. Credit: breakthroughinitiatives.org

It was 1903 that the Wright brothers made the first successful self-propelled flight. Launching themselves to history, they set the foundations for transatlantic flights, supersonic flight and perhaps even the exploration of the Solar System. Now we are on the precipice of travel among the stars but among the many ideas and theories, what is the ultimate and most effective way to explore our nearest stellar neighbours? After all, there are 10,000 stars within a region of 110 light years from Earth so there are plenty to choose from.