A New Study Shows How our Sun Could Permantly Capture Rogue Planets!

This illustration shows a rogue planet traveling through space. Credit: NASA/JPL-Caltech/R. Hurt (Caltech-IPAC)

Interest in interstellar objects (ISOs) was ignited in 2017 when ‘Oumuamua flew through our Solar System and made a flyby of Earth. Roughly two years later, another ISO passed through our Solar System – the interstellar comet 2I/Borisov. These encounters confirmed that ISOs are not only very common, but pass through our Solar System regularly – something that astronomers have suspected for a long time. Even more intriguing is that some of these objects are captured and can still be found orbiting our Sun.

In a recent study, a team of researchers described a region in the Solar System where objects can be permanently captured from interstellar space. Their analysis determined that once objects are captured by our Sun’s gravitational pull and fall into this region—which could include comets, asteroids, and even rogue planets—they will remain in orbit around the Sun and not collide with it. These findings could have drastic implications for ISO studies and proposed missions to rendezvous with some of these objects in the near future.

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Instead of Losing its Atmosphere, an Exoplanet Puffed Up and Held Onto it

Artist's impression of the "hot Neptune" Phoenix orbiting its red giant star. Credit: Credit: Roberto Molar Candanosa/JHU

To date, astronomers have confirmed the existence of 5638 extrasolar planets in 4,199 star systems. In the process, scientists have found many worlds that have defied expectations. This is certainly the case regarding “hot Neptunes,” planets that are similar to the “ice giants” of the outer Solar System but orbit much closer to their stars. But when a Johns Hopkins University-led team of astronomers discovered TIC365102760 b (aka. Pheonix), they observed something entirely unexpected: a Neptune-sized planet that retained its atmosphere by puffing up.

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New Telescope Images of Io are so Good, it Looks like a Spacecraft Took Them

The SHARK?VIS detection image of Io
The SHARK?VIS detection image of Io

The Large Binocular Telescope (LBT), located on Mount Graham in Arizona and run by the University of Arizona, is part of the next generation of extremely large telescopes (ELTs). With two primary mirrors measuring 8.4 m (~27.5 ft), it has a collecting area slightly greater than that of a 30-meter (98.4 ft) telescope. With their resolution, adaptive optics, and sophisticated instruments, these telescopes are expected to probe deeper into the Universe and provide stunning images of everything from distant galaxies to objects in our Solar System.

An international team led by the University of Arizona recently acquired images of Jupiter’s moon Io that were the highest-resolution pictures ever taken by a ground-based telescope. The images revealed surface features measuring just 80 km (50 mi) across, a spatial resolution previously reserved for spacecraft. This includes NASA’s Juno mission, which has captured some of the most stunning images of Io’s volcanoes. These images were made possible by the LBT’s new SHARK-VIS instrument and the telescope’s adaptive optics system.

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White Dwarfs are Often Polluted With Heavier Elements. Now We Know Why

In this artist's illustration, lumps of debris from a disrupted planetesimal are irregularly spaced on a long and eccentric orbit around a white dwarf. Credit: Dr Mark Garlick/The University of Warwick

When stars exhaust their hydrogen fuel at the end of their main sequence phase, they undergo core collapse and shed their outer layers in a supernova. Whereas particularly massive stars will collapse and become black holes, stars comparable to our Sun become stellar remnants known as “white dwarfs.” These “dead stars” are extremely compact and dense, having mass comparable to a star but concentrated in a volume about the size of a planet. Despite being prevalent in our galaxy, the chemical makeup of these stellar remnants has puzzled astronomers for years.

For instance, white dwarfs consume nearby objects like comets and planetesimals, causing them to become “polluted” by trace metals and other elements. While this process is not yet well understood, it could be the key to unraveling the metal content and composition (aka. metallicity) of white dwarf stars, potentially leading to discoveries about their dynamics. In a recent paper, a team from the University of Colorado Boulder theorized that the reason white dwarf stars consume neighboring planetesimals could have to do with their formation.

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What Deadly Venus Can Tell Us About Life on Other Worlds

Earth and Venus. Why are they so different and what do the differences tell us about rocky exoplanet habitability? Image Credit: NASA

Even though Venus and Earth are so-called sister planets, they’re as different as heaven and hell. Earth is a natural paradise where life has persevered under its azure skies despite multiple mass extinctions. On the other hand, Venus is a blistering planet with clouds of sulphuric acid and atmospheric pressure strong enough to squash a human being.

But the sister thing won’t go away because both worlds are about the same mass and radius and are rocky planets next to one another in the inner Solar System. Why are they so different? What do the differences tell us about our search for life?

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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.

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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?

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Formation-Flying Spacecraft Could Probe the Solar System for New Physics

A solar flare erupts on the Sun. Credit: NASA/GSFC/SDO

It’s an exciting time for the fields of astronomy, astrophysics, and cosmology. Thanks to cutting-edge observatories, instruments, and new techniques, scientists are getting closer to experimentally verifying theories that remain largely untested. These theories address some of the most pressing questions scientists have about the Universe and the physical laws governing it – like the nature of gravity, Dark Matter, and Dark Energy. For decades, scientists have postulated that either there is additional physics at work or that our predominant cosmological model needs to be revised.

While the investigation into the existence and nature of Dark Matter and Dark Energy is ongoing, there are also attempts to resolve these mysteries with the possible existence of new physics. In a recent paper, a team of NASA researchers proposed how spacecraft could search for evidence of additional physical within our Solar Systems. This search, they argue, would be assisted by the spacecraft flying in a tetrahedral formation and using interferometers. Such a mission could help resolve a cosmological mystery that has eluded scientists for over half a century.

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DART Changed the Shape of Asteroid Dimorphos, not Just its Orbit

The asteroid Dimorphos was captured by NASA’s DART mission just two seconds before the spacecraft struck its surface on Sept. 26, 2022. Observations of the asteroid before and after impact suggest it is a loosely packed “rubble pile” object. Credit: NASA/JHUAPL

On September 26th, 2022, NASA’s Double Asteroid Redirection Test (DART) collided with the asteroid Dimorphos, a moonlet that orbits the larger asteroid Didymos. The purpose of this test was to evaluate a potential strategy for planetary defense. The demonstration showed that a kinetic impactor could alter the orbit of an asteroid that could potentially impact Earth someday – aka. Potentially Hazardous Asteroid (PHA). According to a new NASA-led study, the DART mission’s impact not only altered the orbit of the asteroid but also its shape!

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What Can We Learn Flying Through the Plumes at Enceladus?

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

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.

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