Space News & Blog Articles

One of the most interesting questions we can ask is, “How did life form?”. To answer it, scientists go back to look at the basic chemical building blocks of life. Those are water, carbon-based organic molecules, silicates, and others. The James Webb Space Telescope offered a peek at the gases, ice particles, and dust surrounding a newborn star and found organic molecules exist there.

The data from Webb is set to transform our understanding of the chemistry of newly formed stars. That’s because the telescope can detect the existence of organic molecules around the protostar MIRI 15398-3359. It’s forming in the Lupus 1 molecular cloud (also known as B228), some 500 light-years away from us. The telescope has found absorption features indicating the existence of water, methanol, ammonia, and methane ices. There also appear to be species of ethanol and acetaldehyde, in addition to carbon monoxide and water vapor. These are all complex organic molecules that can combine to form the building blocks of life.

Using Other Molecules to Track Stellar Activity

Since this is a newborn protostar, it’s showing some jet activity as well. Webb found emission lines from species of iron, neon, silicon, and hydrogen gas. These all trace a bipolar jet moving away from the stormy young star. MIRI 15398-3359, like many others, is still feeding on the envelope of material that created it. The cloud of gas and dust that formed its creche is chemically active.

Essentially, it’s taking simple building blocks and churning out those complex organic molecules. They’re precursors to the chemicals of life—existing long before conditions on any nearby worlds have even formed. This is not the first time astronomers have the raw materials for life’s chemicals in stellar nurseries. Other clouds of gas and dust seem to show these complex chemicals, too. But, Webb’s exquisite data show more details about what’s going on in the cloud.

A false-color image obtained by the James Webb Space Telescope (JWST) of a protostar (orange region in upper left; a different protostar from the one in the present study). JWST uses infrared instruments to study how protostars shape the chemistry of icy clouds (blue wisps). Courtesy: NASA, ESA, CSA

The moons of our Solar System have garnered quite a lot of attention in the last few years, especially pertaining to astrobiology and the search for life beyond Earth. From the Galilean moons of Jupiter to the geysers of Enceladus to the methane lakes on Titan, these small worlds continue to humble us with both their awe and mystery. But do the very same scientists who study these mysterious and intriguing worlds have their own favorite moons? As it turns out, seven such planetary geologists were kind enough to share their favorite Solar System moons with Universe Today!

“My favorite moon is Enceladus, for two reasons,” said Dr. Francis Nimmo, who is a professor in the Earth & Planetary Sciences Department at UC Santa Cruz. “First, it is geologically active, which was very surprising given how tiny it is – it is spewing jets of ice and water vapor into space. Second, because it is kind enough to be giving us free samples of its interior, it makes a very attractive target for future spacecraft missions – you can analyze the composition of the ocean (and even look for life) without having to drill through the ice.”

Image mosaic of Enceladus taken by NASA’s Cassini spacecraft in October 2008 from approximately 25 kilometers (15.6 miles) of the moon’s surface. (Credit: NASA/JPL/Space Science Institute)

Saturn’s sixth-largest moon, Enceladus, was discovered in 1789 by William Herschel, and whose diameter is approximately the size of the State of Arizona. As noted by Dr. Nimmo, Enceladus possesses geysers that discharge ice and water vapor from a series of fissures known as “tiger stripes”. These geysers were first observed by NASA’s Cassini spacecraft during its mission in the 2000s, and Cassini even flew through them to test their composition, finding water vapor, a variety of salts, methane, and carbon dioxide.

“My favorite moon of the Solar System is Io, the innermost of the Galilean satellites of Jupiter,” said Dr. David Williams, who is a research professor in the School of Earth and Space Exploration at Arizona State University. “Discovered by Galileo Galilei in January of 1610, Io is the most geologically active of all of the moons of our Solar System. A Laplace orbital resonance with Jupiter’s other moons Europa and Ganymede results in tidal flexing and heating of Io’s interior, producing an enormous amount of energy that powers over 400 volcanoes on Io’s surface. Io’s volcanic activity, which manifests as both lava flows and lava lakes in caldera-like craters, and in explosive eruption plumes that shoot silicate ash, dust, and sulfur-bearing gases hundreds of kilometers above the surface, results in a world without any large impact craters. This indicates that Io has the geologically youngest surface in the Solar System. Thus, Io serves as an example of potentially active, volcanic lava planets discovered around other stars in our Galaxy.”

New results presented at the 54th Lunar and Planetary Science Conference could change our approach to Mars exploration. Scientists studying the surface of Mars discovered a relict glacier near the planet’s equator. The relict glacier could signal the presence of buried water ice at the planet’s mid-latitudes.

Some areas of the Martian surface are known for light-toned deposits (LTDs.) NASA’s Viking spacecraft spotted them in the late 1970s. Since then, scientists have found them in Valles Marineris, Hebes Chasma, and in other locations on Mars. Their unusual features have captured the attention of researchers who want to understand how they formed.

While LTDs are named for their colour, that’s not the only way they differ. Their surfaces can set them apart from their surroundings, too. The top of LTDs can be rough, in contrast to their smooth-surfaced surroundings.

As scientists have worked to piece together Mars’ geological history, they’ve tried to understand what exactly LTDs are and where they fit in the timeline. In a 2008 paper, researchers presented evidence that some LTDs are vestiges of large-scale spring deposits.

Different teams of researchers have examined the LTDs and reached different conclusions. Some concluded that they’re lacustrine deposits, some suggested they’re made of deposits eroded from walls, some thought they’re aeolian deposits, and some even suggested that they’re volcanic deposits.

Fans of Star Trek were over the Moon when, in 2018, astronomers with the Dharma Planet Survey (DPS) announced the possible detection of 40 Eridani b, an extrasolar planet in the star system 40 Eridani. Located just 16.3 light-years away, this triple-star system happens to be where the planet Vulcan was located in the popular franchise. Based on radial velocity measurements of the system’s primary star (40 Eridani A), the discovery team estimated that “Vulcan” was a rocky planet several times the mass of Earth (a Super-Earth) with an orbital period of 42 days or so.

The existence of this exoplanet has remained a controversial subject ever since. A study released in 2021 concluded that the signal was a false positive, but the debate remained open. Now, according to a new study by an international team of researchers, the detection of 40 Eridani b was a false positive that astronomers mistook for an exoplanet. The study was part of an archival review of exoplanets to identify promising candidates for follow-up studies. So while “Vulcan” is currently off the table, these results could lead to other exciting discoveries in the coming years.

The study, which was recently accepted for publication in The Astronomical Journal, was conducted by researchers from the NASA Exoplanet Science Institute (NExScI), NASA’s Jet Propulsion Laboratory, NASA’s Ames Research Center, the Weizmann Institute of Science, the UCO/Lick Observatory, the Hamburg Observatory, the Cahill Center for Astronomy & Astrophysics, the Tsung-Dao Lee Institute, the Carnegie Institution for Science, the Australian Centre for Astrobiology, and multiple universities and research institutes in the U.S., Australia, and China.

An artist’s illustration of the LUVOIR-A telescope concept. Image Credit: NASA

The study focused on exoplanet candidates identified through the Radial Velocity Method (RV) that were part of the list maintained by the NASA/NSF Extreme Precision Radial Velocity Working Group. This method consists of monitoring stars for signs of motion back and forth, a possible indication of orbiting planets that are gravitationally interacting with them. The purpose was to identify exoplanets for follow-up observations by next-generation space telescopes like the Habital Explonet Observatory (HabEx), the Large UV/Optical/IR Surveyor (LUVOIR), and Starshade Rendezvous missions.