Planet forming disk around Hl Tau

[Merc14]

The upgraded ALMA radio telescope in Chile has obtained what they say is the best ever image of a young star (just a million years old) forming planets in an accretion disk.

http://earthsky.org/...34d95-394012957

Edited November 6, 2014 by Merc14

[bison]

I count 8 gaps between the rings of material. Eight planets already well enough along in formation to form gaps conspicuous enough to be observed from 450 light years away? Remarkable in a system believed to be no more than a million years old.

[Merc14]

Article says this was a part of testing and certification so presumably they will be getting even more detailed images in the very near future. In teh next decade we are going to be served up some amazing images as all these next-gen observatories come on-line.

Edited November 6, 2014 by Merc14

[GoldenRabbit]

Thanks for posting merc14, The birth of a Solar System, Its really hard to find words that describe how amazing this photo is.

[Merc14]

Thanks for posting merc14, The birth of a Solar System, Its really hard to find words that describe how amazing this photo is.

It is an amazing image to say the least and they should be getting better images in the near future as more antennas are brought on-line. I'm not sure if "photo", aas we think of a photo, is the correct term as HL Tau can't be seen at optical wavelengths because of the massive dust and gas cloud that envelops the region. From teh article:

You might also want to know that, at optical wavelength, the star HL Tau can’t be seen at all. It’s hidden in visible light behind a massive envelope of dust and gas, a very vast cloud in space, perhaps in which many stars are forming. But ALMA can see it, because it observes at much longer wavelengths, toward the radio end of the electromagnetic spectrum.

The ALMA telescope recently had its ability to see in detail upgraded, and, in fact, this image was made as part of the testing and verification process for the telescope’s new high-resolution capabilities. NRAO says these capabilities were achieved by:

… spacing the antennas up to 15 kilometers apart. This baseline at millimeter wavelengths enabled a resolution of 35 milliarcseconds, which is equivalent to a penny as seen from more than 110 kilometers away.

Thus ALMA can now compete in image quality with the best optical observatories, according to ALMA Director Pierre Cox. NRAO added:

These long baselines fulfill one of ALMA’s major objectives and mark an impressive technological and engineering milestone. Future observations at ALMA’s longest possible baseline of 16 kilometers will produce even clearer images and continue to expand our understanding of the cosmos.

Don't ask me to decipher Maybe someone like Waspie or bison can explain the workings but I am limited to what I learned gawking around the Smithsonian Air & Space museum with my son. If you ever get the chance it is so worth the time to visit. they have a great section on the electromagnetic spectrum and how we get images from across it at various wavelengths.

[GoldenRabbit]

Thanks for the Info Merc14 must appreciated. Will be looking forward to seeing more images from ALMA in the future

[SolarPlexus]

Nice to see planetary accretion in action. Deep down I knew it works.

[bison]

The longer-than-optical wavelengths that ALMA uses have the disadvantage of smearing out details that shorter, visible light can catch. They get around this problem by placing the receivers kilometers apart. This allows them, by properly combining the images from the widely separated telescopes, to detect fine details as well as if they had a single dish kilometers in diameter. As the article mentions, by this means they've gotten back to a resolution of details as good as optical telescopes.

[Merc14]

Some more news on this system here http://www.extremetech.com/extreme/205119-visible-signs-of-planet-formation-spotted-around-nearby-star

The important part is here:

Tamayo’s first simulation of HL Tau with Saturn-sized reference planets (above) predicted violent interactions that ejected planets and drastically altered orbits. In short, it doesn’t match the image. Then he modeled the system with a “resonant” configuration, and it all started to make sense.

In a resonant system, two planets might have orbits that are very close together (or even crossing), but they orbit at a rate such that they are never in the same region at the same time. This is how Pluto and Neptune, which have crossing orbits, have managed to avoid direct interaction with each other for billions of years. Tamayo’s HL Tau resonant model (seen below) is a very good match for what we see with ALMA. Even if all five planets are the size of Saturn, they

could have remained stable

in the theorized configuration

The article contains some animation that graphically displays there hypothesis.

[Zalmoxis]

An excellent article with exciting animations. Thank you for the update.

[Merc14]

An excellent article with exciting animations. Thank you for the update.

What is great as that was just a calibration shot. Wait till they have everything dialed in.

Edited May 10, 2015 by Merc14

[Zalmoxis]

What is great as that was just a calibration shot. Wait till they have everything dialed in.

I thought that perhaps alien species would often find the same thing and during millennia of surviving and evolving on their own planets they would record things such as a new star forming over the course of their history and depending on how long an intelligent species could realistically survive, such a real recording made over long stretches of time would be a very valuable scientific asset.

[Merc14]

I thought that perhaps alien species would often find the same thing and during millennia of surviving and evolving on their own planets they would record things such as a new star forming over the course of their history and depending on how long an intelligent species could realistically survive, such a real recording made over long stretches of time would be a very valuable scientific asset.

It would also be AWESOME!!