Captured in (Actual) Pictures: The Swirling Birth of Planets

Wow. Wow wow wow wow.

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The disc of gas and cosmic dust around the young star HD 142527. Visible are vast streams of gas flowing across the gap in the disc. The observations were made with the Atacama Large Millimeter/submillimeter Array (ALMA) telescope -- and they're the first-ever direct observations of these streams. (ALMA (ESO/NAOJ/NRAO), S. Casassus et al.)

Since 2009, an international team of astronomers, based in the Chilean Andes, have been studying the molecular gases and tiny dust grains from which stars, planetary systems, galaxies, and, yes, life are formed. As part of their work -- building the Atacama Large Millimeter/submillimeter Array (ALMA) -- the team has been studying HD 142527, a fledgling star that is around 2 million years old, resides about 450 light-years from Earth, and is nearing the end of its formation process. Surrounding the young star -- as typically surrounds young stars -- is a disk of spinning dust and gas, the stuff left over from its formation. Observing HD 142527, the researchers recently saw something amazing: young planets forming around it, revealing a never-before-seen stage of planetary evolution. They have now published their findings in the journal Nature.

To be clear: They saw, with (technology-aided) human eyes, planets in the process of forming. And: They are now sharing the image with the rest of us. And that image is above.

Pretty mind-blowing, right? The first-ever direct observation of this stage of planet genesis, an image of a nascent star hundreds of light years away, and it's science and it's art and it's hard to tell whether it's a photo or the cover of a Pink Floyd album.

Here, for comparison, is a rendering -- just a rendering -- of the process the team observed:

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An artist's impression and shows the disk of gas and cosmic dust around the young star HD 142527 (ALMA (ESO/NAOJ/NRAO)/M.Kornmesser (ESO))

In it, you can see two filaments of gas streaming from HD 142527's outer disk to the inner, across a gap punctuated by young planets. Those fledgling planets -- planetesimals -- form as they travel through the disk, absorbing the material around them and creating gaps as they do so. They then -- scientists believe -- use gravity to channel material across those gaps to the interior, helping the star to grow. That's a process, notes, that has been observed in several newborn solar systems.

Theoretical simulations have predicted those bridges between the inner and outer portions of the disks surrounding stars, but none of them have been directly observed -- until now. Using ALMA to analyze HD 142527's fledgling planetary system, lead scientist Simon Casassus and his team discovered two filaments reaching from the outer disk to the inner, indicating that at least two young planets exist within the space between them. As Casassus notes: "Currently, the only mechanism known to produce such gap-crossing dense molecular flows, with residual carbon monoxide gas more diffusely spread out inside the gap, is planetary formation."