All posts tagged: planetary systems

Astronomers spot signs of comets transporting water to a young solar system PDS 70

Astronomers spot signs of comets transporting water to a young solar system PDS 70

Published by Jenni Sidey

Fast-changing sodium gas around the 5.4-million-year-old star PDS 70 provides evidence that icy exocomets may be plunging into the young system’s inner regions. Computer simulations show that giant planets could scatter planetesimals inward from beyond 54 astronomical units, potentially carrying water and other volatile materials toward forming rocky worlds. The exocomet interpretation remains unconfirmed, but if verified, PDS 70 would be the youngest planetary system known to show this kind of comet activity. A young planetary system 370 light-years away may be showing astronomers something remarkably familiar: icy comets carrying water toward the region where rocky planets could eventually emerge. Astronomers at Lund University in Sweden have found fast-changing clouds of sodium gas around PDS 70, a 5.4-million-year-old star already famous for its actively forming planets. The signals behave much like material released by comets passing close to a star, raising the possibility that frozen bodies from the system’s distant outskirts are being hurled inward. The findings, published in Nature Communications, offer a possible explanation for water vapor previously detected close to the star. The …

Astronomers may have finally detected a moon located outside our solar system

Astronomers may have finally detected a moon located outside our solar system

Published by Jenni Sidey

Astronomers detected a strong 170-day signal suggesting a Jupiter-mass object orbits the brown dwarf CD-35 2722 B. The candidate could be the first convincing exomoon found beyond our Solar System, though more observations are needed. Computer simulations favor one eccentric satellite over a less stable two-satellite system. The discovery blurs the definitions of moons, planets and brown-dwarf companions, and may require new astronomical labels. A strange object may be circling a brown dwarf 65 light-years from Earth, creating a three-level system unlike anything confirmed beyond the Solar System. It could also force astronomers to rethink what counts as a moon. The system, called CD-35 2722, contains a star with about 40 percent to half the Sun’s mass. That star is orbited by CD-35 2722 B, a brown dwarf roughly 37 times as massive as Jupiter. Yet it does not orbit a star. “Being the third wheel in this system makes us want to call it a moon, even if it is nothing like the small, rocky moons we have in our system,” said lead author …

NASA’s Webb telescope detects a third giant planet orbiting Beta Pictoris

NASA’s Webb telescope detects a third giant planet orbiting Beta Pictoris

Published by Jenni Sidey

NASA’s James Webb Space Telescope discovered Beta Pictoris d, a third giant planet orbiting the young star Beta Pictoris, 63 light-years from Earth. The system is now only the second known to contain at least three directly imaged planets. Astronomers identified the planet through its atmospheric “barcode,” including absorption patterns from carbon monoxide, methane and water vapor, rather than relying solely on a visible point of light hidden within the star’s bright debris disk. Beta Pictoris d is estimated to have two to four times Jupiter’s mass and may orbit more than 30 astronomical units from its star, placing it beyond Beta Pictoris b but inside the debris disk’s inner edge. The planet’s gravity may help explain gaps, clumps and other unusual structures in the disk. Its discovery also shows that spectroscopy can reveal planets concealed by dust and scattered starlight while simultaneously measuring their chemistry, temperature and motion. Beta Pictoris d spent years concealed inside one of the brightest debris disks astronomers know. NASA’s James Webb Space Telescope found it not as a clean …

Distant star TOI-5882 appears to have swallowed a planet

Distant star TOI-5882 appears to have swallowed a planet

Published by Jenni Sidey

TOI-5882 looks, at first glance, like an ordinary sun-like star. However, its outer layers hold more lithium than astronomers would expect in a star at this stage of life. This chemical oddity now points to a dramatic possibility. Sometime in its recent past, the star likely swallowed a planet. That star sits about 1,300 light-years away and is still only an early subgiant. This means it has begun to move beyond the main part of its life without yet swelling into a red giant. This matters because stars this age usually lose surface lithium over time. Their outer layers deepen and mix with hotter interior regions where lithium is destroyed. As a result, a strong lithium signal is not supposed to linger. For Brooke Kotten of the University of Michigan, that made TOI-5882 an especially useful target. “You are what you eat, right?” said Kotten, lead author of the report in The Astrophysical Journal. “We know that there’s much more lithium in planetary material than there is in stars. So if a star eats a …