How Growing Giant Planets Fight for Food

Artistic rendition of a protoplanet forming within the accretion disk of a protostar Credit: ESO/L. Calçada http://www.eso.org/public/images/eso1310a/

A new study has shown that in order to grow more than one giant planet in the same solar system, the planets must go through a complicated and intricate dance to prevent one from destroying the other.

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Most Exoplanets Suffer Worse Space Weather Than We Do

An artistic rendering of a series of powerful stellar flares. New research says that flaring activity may not prevent life on exoplanets. CREDIT NASA's Goddard Space Flight Center/S. Wiessinger

We have it relatively easy on the Earth. Our Sun is relatively calm. The space weather environment in the solar system is altogether placid. Things are nice. But new research has shown that we may be the exception rather than the rule, and that many exoplanets face much harsher conditions than we do.

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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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Massive Stars don’t Always Grow Their own Planets. Sometimes They Steal Them

A bright young star shines Credit: NASA/JPL-Caltech

Recently astronomers have discovered Jupiter-sized planets orbiting at extremely large distances from giant stars. How can these stars end up with such big planets at such extreme orbits? A team of researchers has proposed that the answer is that the stars steal those planets from their neighbors.

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Carbon Monoxide is Plentiful in Nebulae, but Then Disappears When Planets Form. Now we Know Where it Goes!

carbon monoxide in protoplanetary disk
ALMA image of the protoplanetary disk surrounding the young star HD 163296 as seen in dust. New studies show there may be carbon monoxide ice there. Courtesy NRAO.

Protoplanetary disks—those nurseries around young stars where planets form—are filled with gas and dust. In particular, many show a lot of carbon monoxide gas. It’s a handy “tracer” to estimate the mass of a cloud, its composition, and even its temperature. It’s also easy to observe. However, astronomers think there should be more of it than they’re observing in many disks. And that prompted a question: where’s the rest of it?

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How Do Hot Jupiters Get So Close to Their Stars?

An illustration of a Hot Jupiter orbiting close to its star. Image Credit: ESA/ATG medialab, CC BY-SA 3.0 IGO

In this age of exoplanet discovery, we’ve discovered thousands of exoplanets of different types. The hot Jupiter is one of the most unusual types. There’s nothing like it in our Solar System.

Hot Jupiters are massive gas planets, and they attract a lot of attention because they’re so close to their stars and reach blistering temperatures. Their existence spawns a lot of questions about their formation and evolution. A new study is trying to answer some of those questions by determining hot Jupiters’ ages.

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Jupiter is up to 9% Rock and Metal, Which Means it Ate a lot of Planets in its Youth

This image of Jupiter's turbulent atmosphere was taken by NASA's Juno spacecraft on December 30, 2020. Image Credit: NASA/JPL-Caltech/SwRI/MSSS

Jupiter is composed almost entirely of hydrogen and helium. The amounts of each closely conform to the theoretical quantities in the primordial solar nebula. But it also contains other heavier elements, which astronomers call metals. Even though metals are a small component of Jupiter, their presence and distribution tell astronomers a lot.

According to a new study, Jupiter’s metal content and distribution mean that the planet ate a lot of rocky planetesimals in its youth.

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We’ve Now Seen Planet-Forming Disks Around Hundreds of Young Stars. What Do They Tell Us?

ALMA's high-resolution images of nearby protoplanetary disks, which are results of the Disk Substructures at High Angular Resolution Project (DSHARP). Credit: ALMA (ESO/NAOJ/NRAO), S. Andrews et al.; NRAO/AUI/NSF, S. Dagnello

Is our Solar System comparable to other solar systems? What do other systems look like? We know from exoplanet studies that many other systems have hot Jupiters, massive gas giants that orbit extremely close to their stars. Is that normal, and our Solar System is the outlier?

One way of addressing these questions is to study the planet-forming disks around young stars to see how they evolve. But studying a large sample of these systems is the only way to get an answer. So that’s what a group of astronomers did when they surveyed 873 protoplanetary disks.

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Hubble Has Been Watching This Planet Form for 13 Years

Researchers were able to directly image newly forming exoplanet AB Aurigae b over a 13-year span using Hubble’s Space Telescope Imaging Spectrograph (STIS) and its Near Infrared Camera and Multi-Object Spectrograph (NICMOS). In the top right, Hubble’s NICMOS image captured in 2007 shows AB Aurigae b in a due south position compared to its host star, which is covered by the instrument’s coronagraph. The image captured in 2021 by STIS shows the protoplanet has moved in a counterclockwise motion over time. Credits: Science: NASA, ESA, Thayne Currie (Subaru Telescope, Eureka Scientific Inc.); Image Processing: Thayne Currie (Subaru Telescope, Eureka Scientific Inc.), Alyssa Pagan (STScI)

Hubble’s most remarkable feature might be its longevity. The Hubble has been operating for almost 32 years and has fed us a consistent diet of science—and eye candy—during that time. For 13 of its 32 years, it’s been checking in on a protoplanet forming in a young solar system about 530 light-years away.

Planet formation is always a messy process. But in this case, the planet’s formation is an “intense and violent process,” according to the authors of a new study.

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