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High-def images show planetary construction sites around nearby stars

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We've known for some time that planets like Earth are born from disks of gas, ice, and dust surrounding stars as they themselves form. But details matter: Planets like Earth form differently than ones like Jupiter, and where in the disk they're born makes a difference in their potential size, composition, and more.

These disks can be many billions of kilometers across, but the distances to stars are vast; even close-by stars are a thousand trillion kilometers from us! It takes powerful telescopes and a lot of clever technology to discern them.

And oh, have I mentioned that astronomers have powerful telescopes and a lot of clever technology?

WHOA. Those images show just six of the 26 debris disks seen around nearby stars found in the Gemini Planet Imager Exoplanet Survey. Debris disks are where the material around the star has already started to coalesce and form smaller objects (like asteroid-sized bodies) and possibly planets as well.

For the survey, astronomers targeted nearby (closer than about 500 light years) young (< 500 million years old) stars known to have too much infrared light coming from them. Stars emit light at different wavelengths in a predictable way, and if they have too much infrared coming from them it means they must have something warm around them — possibly a disk of dust warmed by the star's light.

Over four years they targeted 104 such stars, finding the 26 debris disks they could resolve (that is, the disks were large enough to appears as more than just a dot in their detector) and three more that they classified as protoplanetary disks — younger disks that haven't had enough time to really start getting the planetary formation process going.

These observations are tough, so the astronomers really took advantage of everything they could. First, they used the Gemini South telescope, a monster 10-meter ‘scope in Hawaii, where the conditions are excellent, with steady skies and good viewing. The camera they used, the Gemini Planet Imager, has a coronagraph, a small disk of metal that blocks out the light of the star itself, which can be millions of times brighter than the faint disks.

They also observed in polarized light, where all the waves in the light are aligned the same way. This happens when light bounces off objects like grains of dust, for example, so by filtering out unpolarized light from the star it reduces the glare, increasing the contrast hugely (polarized sunglasses work in a similar way; light reflecting off glass is polarized and is blocked by the glasses, reducing glare).

This does cause some odd issues; light gets more polarized if it's forward scattered, that is, if the light source is behind it from your viewpoint. So, for example, looking at the disk around HR 4796, a star 240 light years away, it seems like there's only half a disk! In reality the disk (more like a ring in this case) goes all the way around, but the back side isn't as polarized and is harder to detect using this method. You'll be forgiven if you think it looks like Praxis from Star Trek VI.

Another advantage of this survey is that all the disks are seen using the same equipment in the same way, making it easier to compare them to each other. On top of that, many of these stars were born together from the same cloud of gas, so their ages and distances are similar, making it even easier to compare them. This makes the survey the largest collection of such resolved disks yet made.

The debris disk around the star HR 32297 is send edge-on so it appears as a line knifing across the star (the star itself is blocked for better contrast). Credit: International Gemini Observatory/NOIRLab/NSF/AURA/T. Esposito (UC Berkeley) Image processing: Travis Rector (University of Alaska Anchorage), Mahdi Zamani & Davide de Martin

All the disks except one seem to have a paucity of dust closer in to the star. That's not surprising; over time small grains of dust get blown out by the fierce light of the young star. That makes these objects more like rings than disks. In general it's thought that planets tend to form closer to their stars than the inner edge of these rings, so even just measuring the ring size helps us understand planetary formation.

There is something undeniably provocative about these images. They're beautiful, certainly, but if you saw them without knowing what they are they'd only be of passing interest.

But when you know what you're seeing — rings of dust billions of kilometers across surrounding young stars quadrillions of kilometers away — then they start to have an actual impact on your brain. And then finding out that these are objects that can be studied, analyzed for composition, mass, and temperature, understanding that we are witnessing planets being born in front of our eyes, well. That's when their actual and wondrous nature is truly revealed.



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lrwrp
18 days ago
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Top 5 Steps to Immerse yourself into the cybersecurity field

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This blog provides details about how to start your career in Cybersecurity
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lrwrp
39 days ago
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??, NC
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How to Become a Contact Tracer

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During an unprecedented rise in unemployment, there is increasing demand for one job: contact tracers. Part of the Centers for Disease Control’s multipronged response to the COVID-19 pandemic, contact tracing involves calling people with suspected and confirmed infections and keeping a record of anyone they may have…

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lrwrp
55 days ago
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How to Clean Your Entire House in 30 Minutes

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No one likes a dirty house. When your living space is cluttered, it makes it harder to focus and get things done. Plus, studies have shown that a messy home can lead to higher levels of stress. But there’s a problem: cleaning your abode is rather dull and can seem to require an overwhelmingly long time commitment. 

While there are times when you do want to dedicate the better part of the day to cleaning every nook and cranny of your house, and occasionally do a thorough decluttering as well, getting your house in reasonably good shape on the regular, or when you have guests coming over, is something you can accomplish in surprisingly short order. 

Cleaning often takes up a lot of time because people don’t create a plan of attack. They wander from room to room, cleaning a little bit here and there, getting distracted, forgetting tools, retracing their steps, and mostly just wasting time. With a bit of organization, you can clean your house much, much faster. Sure, if you’ve got a huge home, it’s going to take a bit more time, but for the average house or apartment, you should be able to complete a basic clean in just thirty minutes. Here’s how.  

Like this illustrated guide? Then you’re going to love our book The Illustrated Art of Manliness! Pick up a copy on Amazon.

Illustrated by Ted Slampyak

The post How to Clean Your Entire House in 30 Minutes appeared first on The Art of Manliness.

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lrwrp
108 days ago
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I feel like this assumes your house has been cleaned recently enough that the dust bunnies haven't gained sentience and reached a relatively advanced level of technology.
??, NC
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The V8 Cadillac CT5-V Will Get A Manual: Spy Photos

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The new Cadillac CT5-V comes with a turbocharged V6 and way less power than the outgoing CTS-V, which is very upsetting. But Cadillac has promised a more powerful version of the CT5, and new spy photos show it may continue the legacy of the manual transmission.

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lrwrp
125 days ago
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It needs a WAGON.
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Ferret
125 days ago
Audi just allowed the RS6 Wagon as a special order direct from the factory in the US. Just need to scrape up $109k :D
lrwrp
125 days ago
If I'm spending 100k, I'm getting the AMG e63 S.
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You Should Set a Cadbury Egg on Fire

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Easter candy is the best candy. No other candy has the range! Not only does Easter candy encompass—nay, embrace—both chocolate and fruit-flavored confections with gusto, you cannot deny that egg-shaped candy is objectively fun and good. (Reese’s eggs have the best peanut butter-to-chocolate ratio; the trees and hearts…

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lrwrp
130 days ago
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intrigued...
??, NC
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