planet formation Archives

February 10, 2023February 10, 2023 by Matt Williams

Machine Learning is a Powerful Tool When Searching for Exoplanets

Three young planets in orbit around an infant star known as HD 163296 Credit: NRAO/AUI/NSF; S. Dagnello

Astronomy has entered the era of big data, where astronomers find themselves inundated with information thanks to cutting-edge instruments and data-sharing techniques. Facilities like the Vera Rubin Observatory (VRO) are collecting about 20 terabytes (TB) of data on a daily basis. Others, like the Thirty-Meter Telescope (TMT), are expected to gather up to 90 TB once operational. As a result, astronomers are dealing with 100 to 200 Petabytes of data every year, and astronomy is expected to reach the “exabyte era” before long.

In response, observatories have been crowdsourcing solutions and making their data open-access so citizen scientists can assist with the time-consuming analysis process. In addition, astronomers have been increasingly turning to machine learning algorithms to help them identify objects of interest (OI) in the Universe. In a recent study, a team led by the University of Georgia revealed how artificial intelligence could distinguish between false positives and exoplanet candidates simultaneously, making the job of exoplanet hunters that much easier.

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.

May 8, 2022May 8, 2022 by Scott Alan Johnston

Even Stars Doomed to Die as Supernovae can Have Planets

90 percent of all exoplanets discovered to date (there are now more than 5000 of them) orbit around stars the same size or smaller than our sun. Giant stars seem to lack planetary companions, and this fact has serious implications for how we understand solar system formation. But is the dearth of planets around large stars a true reflection of nature, or is there some bias inherent in how we look for exoplanets that is causing us to miss them? The recent discovery of two gas giants orbiting a giant star called µ2 Scorpii suggests it might be the latter.

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 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.

January 17, 2022January 17, 2022 by Evan Gough

A Star Passed too Close and Tore Out a Chunk of a Protoplanetary Disk

Scientists have captured an intruder object disrupting the protoplanetary disk—birthplace of planets—in Z Canis Majors (Z CMa), a star in the Canis Majoris constellation. This artist’s impression shows the perturber leaving the star system, pulling a long stream of gas from the protoplanetary disk along with it. Observational data from the Subaru Telescope, Karl G. Jansky Very Large Array, and Atacama Large Millimeter/submillimeter Array suggest the intruder object was responsible for the creation of these gaseous streams, and its “visit” may have other as yet unknown impacts on the growth and development of planets in the star system. Credit: ALMA (ESO/NAOJ/NRAO), B. Saxton (NRAO/AUI/NSF)

When it comes to observing protoplanetary disks, the Atacama Large Millimetre/sub-millimetre Array (ALMA) is probably the champion. ALMA was the first telescope to peer inside the almost inscrutable protoplanetary disks surrounding young stars and watch planets forming. ALMA advanced our understanding of the planet-forming process, though our knowledge of the entire process is still in its infancy.

According to new observations, it looks like chaos and disorder are part of the process. Astronomers using ALMA have watched as a star got too close to one of these planet-forming disks, tearing a chunk away and distorting the disk’s shape.

What effect will it have on planetary formation?

October 27, 2021October 27, 2021 by Evan Gough

This is How You Get Moons. An Earth-Sized World Just got Pummeled by Something Huge.

An MIT-led team has discovered evidence of a giant impact in the nearby HD 17255 star system, in which an Earth-sized terrestrial planet and a smaller impactor likely collided at least 200,000 years ago, stripping off part of one planet’s atmosphere. Credits:Image: Mark A. Garlick

Titanic collisions are the norm in young solar systems. Earth’s Moon was the result of one of those collisions when the protoplanet Theia collided with Earth some 4.5 billion years ago. The collision, or series of collisions, created a swirling mass of ejecta that eventually coalesced into the Moon. It’s called the Giant Impact Hypothesis.

Astronomers think that collisions of this sort are a common part of planet formation in young solar systems, where things haven’t settled down into predictability. But seeing any of these collisions around other stars has proved difficult.

June 7, 2021June 7, 2021 by Paul M. Sutter

Planets may Start Forming Before the Star is Even Finished

An illustration of a protoplanetary disk. The solar system formed from such a disk. Astronomers suggest this birthplace was protected by a larger filament of molecular gas and dust early in history. Credit: NASA/JPL-Caltech/T. Pyle (SSC)

Planets form from the accumulation of countless grains of dust swirling around young stars. New computer simulations have found that planets begin forming earlier than previously thought, when a planet’s star hasn’t even finished forming yet.

April 10, 2021April 10, 2021 by Brian Koberlein

Primordial Asteroids That Never Suffered Massive Collisions all Seem to be Larger Than 100 km. Why?

2004 EW95, seen in this artist view, may be a primordial asteroid. Credit: M. Kornmesser/European Southern Observatory

Planetary systems form out of the remnant gas and dust of a primordial star. The material collapses into a protoplanetary disk around the young star, and the clumps that form within the disk eventually become planets, asteroids, or other bodies. Although we understand the big picture of planetary formation, we’ve yet to fully understand the details. That’s because the details are complicated.