Gaia untangles the starry strings of the Milky Way

Gaia untangles the starry strings of the Milky Way
This diagram shows a face-on view of stellar ‘families’ – clusters (dots) and co-moving groups (thick lines) of stars – within about 3000 light-years from the Sun, which is located at the centre of the image. The diagram is based on data from the second data release of ESA’s Gaia mission. Credit: Courtesy of M. Kounkel & K. Covey (2019)

Rather than leaving home young, as expected, stellar 'siblings' prefer to stick together in long-lasting, string-like groups, finds a new study of data from ESA's Gaia spacecraft.

Exploring the distribution and past history of the starry residents of our galaxy is especially challenging as it requires astronomers to determine the ages of stars. This is not at all trivial, as 'average' stars of a similar mass but different ages look very much alike.

To figure out when a star formed, astronomers must instead look at populations of stars thought to have formed at the same time—but knowing which stars are siblings poses a further challenge, since stars do not necessarily hang out long in the stellar cradles where they formed.

"To identify which stars formed together, we look for stars moving similarly, as all of the stars that formed within the same cloud or cluster would move in a similar way," says Marina Kounkel of Western Washington University, U.S., and lead author of the new study.

"We knew of a few such 'co-moving' star groups near the Solar System, but Gaia enabled us to explore the Milky Way in great detail out to far greater distances, revealing many more of these groups."

Marina used data from Gaia's second release to trace the structure and star formation activity of a large patch of space surrounding the Solar System, and to explore how this changed over time. This data release, provided in April 2018, lists the motions and positions of over one billion stars with unprecedented precision.

Credit: European Space Agency

The analysis of the Gaia data, relying on a machine learning algorithm, uncovered nearly 2000 previously unidentified clusters and co-moving groups of stars up to about 3000 from us—roughly 750 times the distance to Proxima Centauri, the nearest star to the Sun. The study also determined the ages for hundreds of thousands of stars, making it possible to track stellar 'families' and uncover their surprising arrangements.

"Around half of these stars are found in long, string-like configurations that mirror features present within their giant birth clouds," adds Marina.

"We generally thought would leave their birth sites just a few million years after they form, completely losing ties with their original family—but it seems that stars can stay close to their siblings for as long as a few billion years."

The strings also appear to be oriented in particular ways with respect to our galaxy's —something that depends upon the ages of the stars within a . This is especially evident for the youngest strings, comprising stars younger than 100 million years, which tend to be oriented at right angles to the spiral arm nearest to our Solar System.

The astronomers suspect that the older strings of stars must have been perpendicular to the spiral arms that existed when these stars formed, which have now been reshuffled over the past billion years.

Gaia untangles the starry strings of the Milky Way
This diagram shows an edge-on view of stellar ‘families’ – clusters (dots) and co-moving groups (thick lines) of stars – within about 3000 light-years from the Sun, which is located at the centre of the image. The diagram is based on data from the second data release of ESA’s Gaia mission. Credit: Courtesy of M. Kounkel & K. Covey (2019)

"The proximity and orientation of the youngest strings to the Milky Way's present-day spiral arms shows that older strings are an important 'fossil record' of our galaxy's spiral structure," says co-author Kevin Covey, also of Western Washington University, U.S..

"The nature of spiral arms is still debated, with the verdict on them being stable or dynamic structures not settled yet. Studying these older strings will help us understand if the arms are mostly static, or if they move or dissipate and re-form over the course of a few hundred million years—roughly the time it takes for the Sun to orbit around the galactic centre a couple of times."

Gaia was launched in 2013, and is on a mission to chart a three-dimensional map of our galaxy, pinpointing the locations, motions, and dynamics of roughly one percent of the stars within the Milky Way, along with additional information about many of these stars. Further Gaia releases, including more and increasingly precise data, are planned for the coming decade, providing astronomers with the information they need to unfold the star-formation history of our galaxy.

"Gaia is a truly ground-breaking mission that is revealing the history of the Milky Way—and its constituent stars—like never before," adds Timo Prusti, Gaia project scientist at ESA.

"As we will determine the ages for a larger number of stars distributed throughout our galaxy, not just those residing in compact clusters, we'll be in an even better position to analyse how these have evolved over time."


Explore further

Astronomers decode Milky Way's violent birth

More information: Marina Kounkel et al. Untangling the Galaxy. I. Local Structure and Star Formation History of the Milky Way, The Astronomical Journal (2019). DOI: 10.3847/1538-3881/ab339a
Journal information: Astronomical Journal

Citation: Gaia untangles the starry strings of the Milky Way (2019, August 28) retrieved 19 September 2019 from https://phys.org/news/2019-08-gaia-untangles-starry-milky.html
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Aug 28, 2019
One more observation which confirms the predictions set forth by Plasma Cosmology and the Electric Universe and which contradicts the standard guesswork.


Aug 28, 2019
"Each year the Electric Universe holds their annual EU conference, where a seemingly endless parade of misguided fools take to the stage and discuss mythology, homeopathy, dipole gravity, and other equally absurd nonsense. The only common thread is the notion that a conspiracy is afoot to suppress their oddball beliefs."

RNP
Aug 28, 2019
Fascinating.

An open access version of the paper can be found here; https://arxiv.org...7709.pdf

Aug 28, 2019
One more observation which confirms the predictions set forth by Plasma Cosmology and the Electric Universe and which contradicts the standard guesswork.



Confirms nothing.

Aug 28, 2019
One more observation which confirms the predictions set forth by Plasma Cosmology and the Electric Universe and which contradicts the standard guesswork.



How utterly predictable! How utterly wrong!

Aug 28, 2019
"Strings" is plasma ignoramus speak for Birkeland currents. LOL!

Aug 28, 2019
"Strings" is plasma ignoramus speak for Birkeland currents. LOL!


No it is not, you loon. If they were currents, you uneducated clown, we would bloody well see them in synchrotron. We don't. Ergo, your woo is falsified.

Aug 29, 2019
Many of these groups appear to be filamentary or string-like, oriented in parallel to the Galactic plane,


"Filamentation: The Signature of Electrical Currents in Astrophysical Plasmas"
http://plasmauniv...nts.html

As stated, "strings" indicate Birkeland currents in plasmas.

Aug 29, 2019
"Filamentation: The Signature of Electrical Currents in Astrophysical Plasmas"
http://plasmauniv...nts.html

As stated, "strings" indicate Birkeland currents in plasmas.


Linking to Plasma Universe is like saying Sandy Hook didn't happen and then linking to InfoWars as "proof". Way to go champ.

Aug 29, 2019
"Filamentation: The Signature of Electrical Currents in Astrophysical Plasmas"
http://plasmauniv...nts.html

As stated, "strings" indicate Birkeland currents in plasmas.


Linking to Plasma Universe is like saying Sandy Hook didn't happen and then linking to InfoWars as "proof". Way to go champ.

Not quite, the Plasma Universe webpage (hosted by LANL) was written by an expert in the field of plasma physics. The infowars is an unhinged psycho bent on misinformation for the benefit of his masters.

Aug 29, 2019
You'll note that the links at https://plasma.lanl.gov/ are either dead or haven't been updated in a decade, and it looks like PU is only very loosely tied to LANL. The PU website itself looks like something out of 1999 and is clearly the pet project of one individual who may be an "expert" in the field, but is off the mark. In any science you'll find incredibly intelligent experts who hold wrong opinions. Fortunately, science gets to the bottom of all things.

Aug 29, 2019
You'll note that the links at https://plasma.lanl.gov/ are either dead or haven't been updated in a decade, and it looks like PU is only very loosely tied to LANL. The PU website itself looks like something out of 1999 and is clearly the pet project of one individual who may be an "expert" in the field, but is off the mark. In any science you'll find incredibly intelligent experts who hold wrong opinions. Fortunately, science gets to the bottom of all things.

Yep, and the science is doing just that as shown by the confirmation of predictions shown above.

Aug 29, 2019
No, it isn't though. Just saying "Birkeland currents" isn't useful or helpful. You literally attribute everything in every Physorg article to Birkeland currents. Explain how the properties of these currents predicts how stars arrange on a galactic scale.

Do you honestly believe that everything in the universe can be explained by that website? If it held any real value, don't you think it would get more attention? It's a little conspiratorial to think that the entire scientific community intentionally ignores PU because of some nefarious purpose. It's a little Alex Jones-y, which is why I drew the parallel.

Aug 29, 2019
No, it isn't though. Just saying "Birkeland currents" isn't useful or helpful. You literally attribute everything in every Physorg article to Birkeland currents. Explain how the properties of these currents predicts how stars arrange on a galactic scale.

Do you honestly believe that everything in the universe can be explained by that website? If it held any real value, don't you think it would get more attention? It's a little conspiratorial to think that the entire scientific community intentionally ignores PU because of some nefarious purpose. It's a little Alex Jones-y, which is why I drew the parallel.

See here;
https://phys.org/...end.html
As the darkist die off so too will their pseudoscience.

Aug 29, 2019
What an asinine statement.
What happens then when the 2 or 3 people (with an actual formal education) that contribute to PU die off?

Explain how the properties of these currents predicts how stars arrange on a galactic scale.
Not interested in opinions about what happens when scientists die, I'm interested in seeing evidence that supports your claim.

Aug 29, 2019

See here;
https://phys.org/...end.html
As the darkist die off so too will their pseudoscience.


Lol. They have real science. You have pseudoscience (if I'm being kind!). Where are these up and coming scientifically illiterate., innumerate, Velikovskian loons who are going to take science by storm? Let's see; PU has Peratt. He's ancient. That's about it. Lerner is also cracking on, but is a complete nobody anyway. Anyone else? Nah.

Aug 29, 2019
Explain how the properties of these currents predicts how stars arrange on a galactic scale.
Not interested in opinions about what happens when scientists die, I'm interested in seeing evidence that supports your claim.


Play fair Mr B! Asking EUists to provide science and evidence is the equivalent asking them to do maths! Simply not fair! Why do you need all that science stuff when you have Wal and Dave and Don and Velikovsky?

Aug 29, 2019
Apparently so. It's like having a conversation with that one family member that's a flat earther and they finally end the conversation with "you're just closed-minded!" I'm not sure why some otherwise intelligent people latch onto these ideas and then become adversarial, insisting everyone else must be wrong.

yep
Aug 30, 2019
Math is not empirical evidence of anything and If you had any knowledge of science history, you would know many of today's scienticfic truths will not be tomorrow.

Aug 30, 2019
So math is not empirical evidence that if I have two bananas and give you one, we each have one banana?

OK.

yep
Sep 01, 2019
So math is not empirical evidence that if I have two bananas and give you one, we each have one banana?
OK.

The empirical evidence in your statement was not the math.
Maybe this will help get you and your clown posse's feeble minds around it.
OK.
http://www.ditext...ath.html

Sep 01, 2019
Nope. Going with the bananas.

Cranks can't count.

yep
Sep 01, 2019
Nope. Going with the bananas.
Cranks can't count.

Because you can't be bothered to educate yourself on the definition of empirical science and prefer to remain ignorant.
Your not to old to learn try it sometime.
This article will give you a greater understanding of science and how it works, you will learn a few things and ultimately appreciate it.
Your Welcome.
http://www.ditext...ath.html


Sep 01, 2019
Two bananas looks pretty empirical to me.

science and how it works
looks to me like you have no idea how science works since you can't even figure out how two bananas work.

#CranksCantCount

Sep 01, 2019
Your not to old to learn try it sometime.

Your Welcome.


Translation; 'too old', not 'to'. 'You're', not 'your'.

Forget maths, deal with English first! We'll teach you maths once you've figured that out.

Sep 01, 2019
@Da Schneib
@Castro

It would be objectively prudent for you/all to read carefully @yep's linked explanation of math's actual nature/role in our scientific/analytic constructs/activities/conclusions etc. I specifically draw your attention to this short paragraph therein:
Thus, in the establishment of empirical knowledge, mathematics (as well as logic) has, so to speak, the function of a theoretical juice extractor: the techniques of mathematical and logical theory can produce no more juice of factual information than is contained in the assumptions to which they are applied; but they may produce a great deal more juice of this kind than might have been anticipated upon a first intuitive inspection of those assumptions which form the raw material for the extractor.
It succinctly encapsulates all the things which I have over the years been trying to explain to you re abstractions vs reality.

ps: re your bananas: one may be green (unripe); one yellow (ripe). :)

yep
Sep 02, 2019
These post are more evidence in proving Planck's conjecture that the deathbed is the way to move science forward.
Why would you actually want to learn when think you already know.
It would be "objectively prudent" but unlikely since attacking my shortcomings detracts from their own. It is hard for some to set aside their ego's.
I applaud you Reality Check for trying to keep it civil and help them learn but as stated previously, they lack. Ironically their statements are empirical evidence.

Sep 02, 2019
So basically you're waiting for people who can count to die off.

Good luck with that.

Sep 02, 2019
@Da Schneib.

Mate, being flippant and evasive of the point made in @yep's referenced link is demonstrating your lack of objectivity and honesty. Please don't keep making the same mistakes as you did all these years, by ignoring the actual point and just posting one-liner evasions which tacitly demonstrate you are not fair dinkum because you are prejudiced and lack the ability to actually see beyond your pre-conditioned stances which are being falsified while you deny and ignore and make fun of your interlocutors. That is what AGW deniers do; and you are being no better than them in the matter of what maths is, and what it is not. You would do well to read @yep's linked explanation. It was written long ago; and is now even more relevant/crucial to understanding the difference between abstract analytical/descriptive constructs and actual reality-based observations/assumptions built into those observations via experience.

The MAP is NOT the TERRITORY.

Be objective. :)

Sep 05, 2019
@RealityCheck
I'm a bit late by several days, but I just want to say, 'good show, old boy'. You have done well.

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