Solar System Archives

March 28, 2023April 1, 2023 by Laurence Tognetti

Europa’s Ice Rotates at a Different Speed From its Interior. Now We May Know Why

Image of Europa taken by NASA's Juno spacecraft on Sept 29, 2022. (Credit: NASA/JPL-Caltech/Southwest Research Institute/Malin Space Science Systems)

Jupiter’s moon, Europa, contains a large ocean of salty water beneath its icy shell, some of which makes it to the surface from time to time, and this vast ocean could host life, as well. Europa was most recently observed by NASA’s Juno spacecraft, but current examinations of the moon’s internal ocean are limited to computer models and simulations produced here on Earth, as no mission is actively exploring this tiny moon orbiting Jupiter. Other than the internal water occasionally breaching the icy shell and making it to the surface, what other effects could the internal ocean have on the icy shell that encloses it?

March 28, 2023March 28, 2023 by Matt Williams

Moons Orbiting Rogue Planets Could be Habitable

An artist's conception of a potentially-habitable exomoon. Credit: NASA

When looking for signs of life beyond the Solar System, astrobiologists are confined to looking for life as we understand it. For the most part, that means looking for rocky planets that orbit within their star’s circumsolar habitable zone (HZ), the distance at which liquid water can exist on its surface. In the coming years, next-generation telescopes and instruments will allow astronomers to characterize exoplanet atmospheres like never before. When that happens, they will look for the chemical signatures we associate with life, like nitrogen, oxygen, carbon dioxide, methane, and ammonia.

However, astrobiologists have theorized that life could exist in the outer Solar System beneath the surfaces of icy moons like Europa, Callisto, Titan, and other “Ocean Worlds.” Because of this, there is no shortage of astrobiologists who think that the search for extraterrestrial life should include exomoons, including those that orbit free-floating planets (FFPs). In a recent study, researchers led by the Max Planck Institute for Extraterrestrial Physics (MPE) determined the necessary properties that allow moons orbiting FFPs to retain enough liquid water to support life.

March 20, 2023March 20, 2023 by Laurence Tognetti

The Favorite Solar System Moons of Planetary Geologists; An In-Depth Discussion

The Galilean moons of Jupiter: Io, Europa, Ganymede, and Callisto. (Credit: NASA/JPL-Caltech)

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!

February 21, 2023February 22, 2023 by Laurence Tognetti

Meteorites are Contaminated Quickly When They Reach Earth

Image of an Earth-altered sample of the Winchcombe meteorite; scale bar in micrometers. (Credit: University of Glasgow)

On Earth, geologists study rocks to help better understand the history of our planet. In contrast, planetary geologists study meteorites to help better understand the history of our solar system. While these space rocks put on quite the spectacle when they enter our atmosphere at high speeds, they also offer insights into both the formation and evolution of the solar system and the planetary bodies that encompass it. But what happens as a meteorite traverses our thick atmosphere and lands on the Earth? Does it stay in its pristine condition for scientists to study? How quickly should we contain the meteorite before the many geological processes that make up our planet contaminate the specimen? How does this contamination affect how the meteorite is studied?

February 8, 2023February 8, 2023 by Evan Gough

Dwarf Planet Quaoar has a Ring

This artist’s impression shows the dwarf planet Quaoar and its ring. Quaoar’s moon Weywot is shown on the left. Quaoar’s ring was discovered through a series of observations that took place between 2018 to 2021. Image Credit: http://www.esa.int/spaceinvideos/Terms_and_Conditions

Quaoar is one of about 3,000 dwarf planets in our Solar System’s Kuiper Belt. Astronomers discovered it in 2002. It’s only half as large as Pluto, about 1,121 km (697 mi) in diameter. Quaoar has a tiny moon named Weywot, and the planet and its moon are very difficult to observe in detail.

Astronomers took advantage of an occultation to study the dwarf planet Quaoar and found that it has something unexpected: a ring where a moon should be.

January 31, 2023January 31, 2023 by Laurence Tognetti

Freezing Ocean Might Not Be Responsible for Cryovolcanic Flows on Pluto’s Moon, Charon

Color-enhanced image of Pluto's largest moon, Charon, taken by NASA's New Horizons spacecraft on July 14, 2015. (Credit: NASA/Johns Hopkins University Applied Physics Laboratory/Southwest Research Institute)

In a recent study scheduled to be published in the journal Icarus in March 2023, a team of researchers led by the Southwest Research Institute (SwRI) modeled a potential correlation between an ancient freezing ocean with cryovolcanic flows and surface canyons on Pluto’s largest moon, Charon. Their hypothesis was that when Charon’s interior ocean froze long ago, the significant stress put on the icy outer shell from the addition of more ice to the bottom of the existing shell could have been responsible for the cryovolcanic flows on the surface.

January 30, 2023February 3, 2023 by Laurence Tognetti

The Outer Solar System Supplied a Surprising Amount of Earth’s Water

Currently exploring the Kuiper Belt, New Horizons is just one of five spacecraft to reach beyond 50 astronomical units, on its way out of the solar system and, eventually, into interstellar space. (Credit: NASA/Johns Hopkins APL/Southwest Research Institute)

In a recent study published in Science, a team of researchers at Imperial College London examined 18 meteorites containing the volatile element zinc to help determine their origin, as it has been long hypothesized that Earth’s volatiles materials, including water, were derived from asteroids closer to our home planet. However, their results potentially indicate a much different origin story.

January 30, 2023January 31, 2023 by Laurence Tognetti

Scientists Examine Geological Processes of Monad Regio on Neptune’s Largest Moon, Triton

Global color mosaic of Neptune's largest moon, Triton, taken by NASA's Voyager 2 in 1989. (Credit: NASA/JPL-Caltech/USGS)

In a recent study submitted to the journal Icarus, a team of researchers at the International Research School of Planetary Science (IRSPS) located at the D’Annunzio University of Chieti-Pescara in Italy conducted a geological analysis of a region on Neptune’s largest moon, Triton, known as Monad Regio to ascertain the geological processes responsible for shaping its surface during its history, and possibly today. These include what are known as endogenic and exogenic processes, which constitute geologic processes occurring internally (endo-) and externally (exo-) on a celestial body. So, what new insights into planetary geologic processes can we learn from this examination of Monad Regio?

January 16, 2023January 16, 2023 by Laurence Tognetti

NASA’s Psyche Mission is Back on. It’ll Launch Towards its Metal Asteroid Target Later This Year

A June 2020 artist illustration of NASA's Psyche spacecraft. (Credit: NASA/JPL-Caltech/Arizona State University)

NASA’s Psyche mission is back on track for launch and is now scheduled for a potential October 2023 launch date, according to an October 2022 statement from NASA. This comes after missing its originally planned launch date between August and October of 2022, and becoming subject to an independent review board, whose results were announced in November 2022.

January 11, 2023January 11, 2023 by Laurence Tognetti

Will Pluto finally answer, ‘Are we alone?’

Two features that could be cryovolcanoes exist on Pluto. They lay on either side of heart-shaped Sputnik Planitia in this color-enhanced image of Pluto from NASA’s New Horizons spacecraft taken in July 2015. (Credit: NASA / Johns Hopkins University Applied Physics Laboratory (JHUAPL) / Southwest Research Institute (SwRI))

We previously examined how Neptune’s largest moon, Triton, could answer the longstanding question: Are we alone? With its nitrogen geysers discovered by NASA’s Voyager 2 spacecraft, possible interior ocean, and lack of craters, Triton could be geologically active, which makes it an excellent celestial body for future astrobiology missions. But Triton isn’t the only place on the edge of the solar system which garners interest for finding life beyond Earth, as one of the most familiar and well-known (former) planets also exhibits evidence of recent geological activity and crater-less surface features. This is everyone’s favorite dwarf planet, Pluto, which like Triton has only been visited by one spacecraft, this one being NASA’s New Horizons, in 2015. But even with only one visitation, we discovered so much about Pluto, and what it might be hiding, as well.