Planetary Formation Archives

September 13, 2022September 12, 2022 by Paul M. Sutter

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

Artist's conception of early planetary formation from gas and dust around a young star. Outbursts from newborn and adolescent stars might drive planetary water beneath the surface of rocky worlds. Credit: NASA/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.

August 25, 2022August 25, 2022 by Carolyn Collins Petersen

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?

June 15, 2022June 15, 2022 by Evan Gough

How Do Hot Jupiters Get So Close to Their Stars?

Thi 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.

June 10, 2022June 10, 2022 by Evan Gough

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.

May 12, 2022May 12, 2022 by Evan Gough

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). The observatory is often used to look for planet birth clouds like these and the one around HD 169142. 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.

April 5, 2022April 5, 2022 by Evan Gough

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.

April 4, 2022April 4, 2022 by Evan Gough

Primordial Helium, Left Over From the Big Bang, is Leaking Out of the Earth

The center of Lagoon Nebula, captured by the Hubble Telescope. Nebulae are the primary sources of helium-3, and the amount of He-3 leaking from the Earth’s core suggests the planet formed inside the solar nebula, according to a new study in the AGU journal Geochemistry, Geophysics, Geosystems. Credit: NASA, ESA

Something ancient and primordial lurks in Earth’s core. Helium 3 (³He) was created in the first minutes after the Big Bang, and some of it found its way through time and space to take up residence in Earth’s deepest regions. How do we know this?

Scientists can measure it as it slowly escapes.

March 24, 2022March 24, 2022 by Evan Gough

Astronomers See the Wreckage Where Planets Crashed Into Each Other in a Distant Star System

This illustration depicts the result of a collision between two large asteroid-sized bodies. NASA's Spitzer saw a debris cloud block the star HD 166191, giving scientists details about the smashup that occurred. Credit: NASA/JPL-Caltech

Our Solar System was born in chaos. Collisions shaped and built the Earth and the other planets, and even delivered the building blocks of life. Without things smashing into each other, we might not be here.

Thankfully, most of the collisions are in the past, and now our Solar System is a relatively calm place. But frequent collisions still occur in other younger solar systems, and astronomers can see the aftermath.

March 14, 2022March 14, 2022 by Evan Gough

Planets Have Just Started to Form in This Binary System

Binary stars are common and imaging their planets will be a challenge. How can astronomers block all that light so they can see the planets? This artist's illustration shows the eclipsing binary star Kepler 16, as seen from the surface of an exoplanet in the system. Image Credit: NASA

Astronomers have watched the young binary star system SVS 13 for decades. Astronomers don’t know much about how planets form around proto-binary stars like SVS 13, and the earliest stages are especially mysterious. A new study based on three decades of research reveals three potentially planet-forming disks around the binary star.

February 24, 2022February 24, 2022 by Evan Gough

Mini-Neptunes can Lose gas and Turn Into Super-Earths

An artist's illustration of the mini-Neptune TOI 560.01 losing its atmosphere and transitioning to a super-Earth. Image Credit: Image Credit: Adam Makarenko (Keck Observatory)

Can one type of planet become another? Can a mini-Neptune lose its atmosphere and become a super-Earth? Astronomers have found two examples of mini-Neptunes transitioning to super-Earths, and the discovery might help explain a noted “gap” in the size distribution of exoplanets.