moons Archives

June 19, 2024June 19, 2024 by Evan Gough

If We Want To Find Life-Supporting Worlds, We Should Focus on Small Planets With Large Moons

A rocky planet with a large moon may have good potential to host life, given that the Moon controls essential aspects for life on Earth, including the length of the day, ocean tides, and stable climate. Image Credit: University of Rochester photo illustration by Michael Osadciw featuring Unsplash photography from Brad Fickeisen, Jaanus Jagomagi, and Engin Akyurt

There’s no perfect way of doing anything, including searching for exoplanets. Every planet-hunting method has some type of bias. We’ve found most exoplanets using the transit method, which is biased toward larger planets. Larger planets closer to their stars block more light, meaning we detect large planets transiting in front of their stars more readily than we detect small ones.

That’s a problem because some research says that life-supporting planets are more likely to be small, like Earth. It’s all because of moons and streaming instability.

June 4, 2024June 4, 2024 by Evan Gough

How Mars’ Moon Phobos Captures Our Imaginations

This is a colourized version of a black and white image captured by the ESA's Mars Express in 2010. Andrea Luck, a skilled image processor from Glasgow, improved the original image. Image Credit: ESA/DLR/FUBerlin/AndreaLuck CC BY. Original Image: https://www.planetary.org/space-images/20130714_phobosnd_img

For a small, lumpy chunk of rock that barely reflects any light, Mars’ Moon Phobos draws a lot of attention. Maybe because it’s one of only two moons to orbit the planet, and its origins are unclear. But some of the attention is probably because we have such great images of it.

April 18, 2024April 18, 2024 by Allen Versfeld

Are Titan's Dunes Made of Comet Dust?

Two different dune fields on Titan: Belet and Fensal, as imaged by Cassini’s radar. It also shows two similar dune fields on Earth in Rub Al Khali, Saudi Arabia. CREDIT NASA/JPL–Caltech/ASI/ESA and USGS/ESA — Two different dune fields on Titan: Belet and Fensal, as imaged by Cassini’s radar. It also shows two similar dune fields on Earth in Rub Al Khali, Saudi Arabia. Credit: NASA/JPL–Caltech/ASI/ESA and USGS/ESA

A new theory suggests that Titan’s majestic dune fields may have come from outer space. Researchers had always assumed that the sand making up Titan’s dunes was locally made, through erosion or condensed from atmospheric hydrocarbons. But researchers from the University of Colorado want to know: Could it have come from comets?

April 11, 2024April 11, 2024 by Evan Gough

Did An Ancient Icy Impactor Create the Martian Moons?

A composite image of Mars and its two moons, Phobos (foreground) and Deimos (background). Credit: NASA/JPL/University of Arizona

The Martian moons Phobos and Deimos are oddballs. While other Solar System moons are round, Mars’ moons are misshapen and lumpy like potatoes. They’re more like asteroids or other small bodies than moons.

Because of their odd shapes and unusual compositions, scientists are still puzzling over their origins.

March 27, 2024March 27, 2024 by Evan Gough

A Single Grain of Ice Could Hold Evidence of Life on Europa and Enceladus

The Cassini spacecraft captured this image of cryovolcanic plumes erupting from Enceladus' ice-capped ocean. Image Credit: NASA/JPL/CalTech

The Solar System’s icy ocean moons are primary targets in our search for life. Missions to Europa and Enceladus will explore these moons from orbit, improving our understanding of them and their potential to support life. Both worlds emit plumes of water from their internal oceans, and the spacecraft sent to both worlds will examine those plumes and even sample them.

New research suggests that evidence of life in the moons’ oceans could be present in just a single grain of ice, and our spacecraft can detect it.

March 26, 2024March 26, 2024 by Evan Gough

Europe Has Big Plans for Saturn’s Moon Enceladus

A false-colour image of the plumes erupting from Enceladus. Image Credit: NASA/ESA

Saturn’s moon, Enceladus, is a gleaming beacon that captivates our intellectual curiosity. Its clean, icy surface makes it one of the most reflective objects in the entire Solar System. But it’s what’s below that ice that really gets scientists excited.

Under its icy shell is an ocean of warm, salty water, and the ESA says investigating the moon should be a top priority.

March 13, 2024March 16, 2024 by Matt Williams

What Can We Learn Flying Through the Plumes at Enceladus?

In the next decade, space agencies will expand the search for extraterrestrial life beyond Mars, where all of our astrobiology efforts are currently focused. This includes the ESA’s JUpiter ICy moon’s Explorer (JUICE) and NASA’s Europa Clipper, which will fly past Europa and Ganymede repeatedly to study their surfaces and interiors. There’s also NASA’s proposed Dragonfly mission that will fly to Titan and study its atmosphere, methane lakes, and the rich organic chemistry happening on its surface. But perhaps the most compelling destination is Enceladus and the lovely plumes emanating from its southern polar region.

Since the Cassini mission got a close-up look at these plumes, scientists have been aching to send a robotic mission there to sample them – which appear to have all the ingredients for life in them. This is not as easy as it sounds, and there’s no indication flying through plumes will yield intact samples. In a recent paper, researchers from the University of Kent examined how the velocity of a passing spacecraft (and the resulting shock of impact) could significantly affect its ability to sample water and ice within the plumes.

March 7, 2024March 7, 2024 by Evan Gough

Perseverance Sees Phobos, Deimos and Mercury Passing in Front of the Sun

NASA's Perseverance Mars rover used its Mastcam-Z camera to capture the silhouette of Phobos, the larger of Mars' pair of moons, as it passed in front of the Sun on Feb. 8, 2024, the 1,056th Martian day, or sol, of the mission. Image Credit: NASA/JPL-Caltech/ASU/MSSS/SSI

NASA’s Perseverance rover is busy exploring the Martian surface and collecting samples for eventual return to Earth. But the rover recently took some time to gaze upward and observe the heavens. Using Mastcam-Z, the rover’s primary science camera, Perseverance captured Phobos, Deimos, and Mercury as they transited in front of the Sun.

March 1, 2024March 1, 2024 by Evan Gough

How Warm Are the Oceans on the Icy Moons? The Ice Thickness Provides a Clue.

Jupiter's moon Ganymede is the largest moon in the Solar System and may have an ocean sandwiched between two layers of ice. But how warm is that ocean? Image Credit: By National Oceanic and Atmospheric Administration Public Domain, https://commons.wikimedia.org/w/index.php?curid=8070396

Scientists are discovering that more and more Solar System objects have warm oceans under icy shells. The moons Enceladus and Europa are the two most well-known, and others like Ganymede and Callisto probably have them too. Even the dwarf planet Ceres might have an ocean. But can any of them support life? That partly depends on the water temperature, which strongly influences the chemistry.

We’re likely to visit Europa in the coming years and find out for ourselves how warm its ocean is. Others on the list we may never visit. But we may not have to.

February 27, 2024February 27, 2024 by Evan Gough

New Moons Found at Uranus and Neptune

The discovery image of the new Uranian moon S/2023 U1 using the Magellan telescope on November 4, 2023. Uranus is just off the field of view in the upper left, as seen by the increased scattered light. S/2023 U1 is the faint point of light in the center of the image with the yellow arrow. The trails are from background stars. Credit: Scott Sheppard.

Astronomers have found three new moons orbiting our Solar System’s ice giants. One is orbiting Uranus, and two are orbiting Neptune. It took hard work to find them, including dozens of time exposures by some of our most powerful telescopes over several years. All three are captured objects, and there are likely more moons around both planets waiting to be discovered.