Lucy Adds Another Asteroid to its Flyby List

This artist's illustration shows NASA's Lucy spacecraft close to one of its targets. NASA has added another asteroid, the eleventh, to Lucy's mission. Image Credit: NASA/SWRI/GSFC

In October 2021, NASA launched its ambitious Lucy mission. Its targets are asteroids, two in the main belt and eight Jupiter trojans, which orbit the Sun in the same path as Jupiter. The mission is named after early hominin fossils (Australopithecus afarensis,) and the name pays homage to the idea that asteroids are fossils from the Solar System’s early days of planet formation.

Visiting ten asteroids in one mission is the definition of ambitious, and now NASA is adding an eleventh.

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How Many Stars Formed Together With the Sun in Our Stellar Nebula?

This is a two-panel mosaic of part of the Taurus Giant Molecular Cloud, the nearest active star-forming region to Earth. The darkest regions are where stars are being born. Image Credit: Adam Block /Steward Observatory/University of Arizona

Even though our Sun is now a solitary star, it still has siblings somewhere in the Milky Way. Stars form in massive clouds of gas called Molecular Clouds. When the Sun formed about five billion years ago, other stars would’ve formed from the same cloud, creating a star cluster.

How many other stars formed in the cluster?

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Earth’s Water is 4.5 Billion Years Old

A new research article shows that Earth's water is as old as the Solar System, and has been present as the Sun grew and the planets formed. Image Credit: NASA/JPL

The origin of Earth’s water has been an enduring mystery. There are different hypotheses and theories explaining how the water got here, and lots of evidence supporting them.

But water is ubiquitous in protoplanetary disks, and water’s origin may not be so mysterious after all.

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The Oort Cloud Could Have More Rock Than Previously Believed

This artist's concept puts Solar System distances in perspective. The scale bar is in astronomical units, with each set distance beyond 1 AU representing 10 times the previous distance (logarithmic scale.) The image shows Voyager 2's location in 2018. (It also shows where the star Ross 248 will be in 40,000 years, when it will briefly be the closest star to the Sun.) Image Credit: NASA/JPL-Caltech

The Oort Cloud is a collection of icy objects in the furthest reaches of the Solar System. It contains the most distant objects in the Solar System, and instead of orbiting on a plane like the planets or forming a ring like the Kuiper Belt, it’s a vast spherical cloud centred on the Sun. It’s where comets originate, and beyond it is interstellar space.

At least that’s what scientists think; nobody’s ever seen it.

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Asteroids Didn’t Create the Moon’s Largest Craters. Left-Over Planetesimals Did

The largest impact basin on the Moon is the South-Pole Aitken basin. It, and other impact basins, were created by planetesimals according to a new study. Image Credit: Moriarty et al., 2021.

The Moon’s pock-marked surface tells the story of its history. It’s marked by over 9,000 impact craters, according to the International Astronomical Union (IAU.) The largest ones are called impact basins, not craters. According to a new study, asteroids didn’t create the basins; leftover planetesimals did.

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Comets Leave Dusty Trails That Surround the Solar System

Could the solar system be enveloped in a shell of faintly glowing dust from comets? Courtesy NASA/ESA/STSci

Comets are messy things. They scatter bits of dust as they travel through the solar system. If Earth happens to encounter one of those cometary dust trails, we get to see a meteor shower.

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Will We Ever Go Back to Explore the Ice Giants? Yes, If We Keep the Missions Simple and Affordable

Uranus and Neptune are begging to be visited, but expensive missions to visit them may never be approved. Image Credits: (L) By NASA – http://photojournal.jpl.nasa.gov/catalog/PIA18182, Public Domain, https://commons.wikimedia.org/w/index.php?curid=121128532. (R) By Justin Cowart – https://www.flickr.com/photos/[email protected]/29347980845/, Public Domain, https://commons.wikimedia.org/w/index.php?curid=82476611

It’s been over 35 years since a spacecraft visited Uranus and Neptune. That was Voyager 2, and it only did flybys. Will we ever go back? There are discoveries waiting to be made on these fascinating ice giants and their moons.

But complex missions to Mars and the Moon are eating up budgets and shoving other endeavours aside.

A new paper shows how we can send spacecraft to Uranus and Neptune cheaply and quickly without cutting into Martian and Lunar missions.

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Baby Gas Giants Cast Shadows on Their Siblings

A computer-generated image depicting a dark protostellar disk seen edge-on at 90 degrees to jets (orange) emanating from the poles of a young star. Such disks are thought to be the precursors of planetary systems, with planets forming as the dust coalesces. RIKEN researchers may have spotted embryos of gas giant planets in one protostellar disk. Credit: Mark Garlick/Science Photo Library

A team of astronomers has caught glimpses of gas giants forming around a very young star.

The nascent giants are having a chilling effect on their potential siblings.

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Mars Once had Enough Water for a Planet-Wide Ocean 300 Meters Deep

This artist’s impression shows how Mars may have looked about four billion years ago. The young planet Mars would have had enough water to cover its entire surface in a liquid layer about 140 metres deep, but it is more likely that the liquid would have pooled to form an ocean occupying almost half of Mars’s northern hemisphere, and in some regions reaching depths greater than 1.6 kilometres. Credit: ESO/M. Kornmesser

Today, Mars is colloquially known as the “Red Planet” on a count of how its dry, dusty landscape is rich in iron oxide (aka. “rust”). In addition, the atmosphere is extremely thin and cold, and no water can exist on the surface in any form other than ice. But as the Martian landscape and other lines of evidence attest, Mars was once a very different place, with a warmer, denser atmosphere and flowing water on its surface. For years, scientists have attempted to determine how long natural bodies existed on Mars and whether or not they were intermittent or persistent.

Another important question is how much water Mars once had and whether or not this was enough to support life. According to a new study by an international team of planetary scientists, Mars may have had enough water 4.5 billion years ago to cover it in a global ocean up to 300 meters (almost 1,000 feet) deep. Along with organic molecules and other elements distributed throughout the Solar System by asteroids and comets at this time, they argue, these conditions indicate that Mars may have been the first planet in the Solar System to support life.

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NASA Provides a Timelapse Movie Showing How the Universe Changed Over 12 Years

This mosaic is composed of images covering the entire sky, taken by the Wide-field Infrared Survey Explorer (WISE) as part of WISE’s 2012 All-Sky Data Release. By observing the entire sky, WISE can search for faint objects, like distant galaxies, or survey groups of cosmic objects. Credits: NASA/JPL-Caltech/UCLA

The Universe is over 13 billion years old, so a 12-year slice of that time might seem uneventful. But a timelapse movie from NASA shows how much can change in just over a decade. Stars pulse, asteroids follow their trajectories, and distant black holes flare as they pull gas and dust toward themselves.

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