Searching for Our Sun's Sisters/Siblings

When the Sun was born, it was most likely in a nebulous stellar nursery similar to the Pleiades and the “Pillars of Creation Nebula” (both shown below):



Inside these nurseries, hundreds or even thousands of stars and solar systems can form out of the dust and gas that are present. That is what we can see here in this image of protoplanetary disks forming inside the Orion Nebula. These disks are infant solar systems that are just getting their start in life:


So, if the Sun and our solar system formed in a similar manner, and in a similar “stellar nursery”, then did the Sun have sisters who were formed near it and at roughly the same time, and from the same raw materials?
The answer seems to be that the Sun has hundreds or even thousands of “sister” stars who were all born in the same place and from the same raw materials.

Most stars are born in clusters rather than singly, and there’s plenty of evidence that the Sun was too.
For one thing, the material of the infant solar system (as preserved in the earliest meteorites) was enriched by fresh supernova debris from at least one very young, massive star (having 15 to 25 solar masses) that exploded less than 5 light-years away, no more than 2 million years after the Sun's formation. Today no such massive star exists within 300 light-years of the Sun. Clearly, the early solar system had stars close around it.

Source:
The Lost Siblings of the Sun


The idea that the raw materials that created our Sun and our solar system was enriched by at least one supernova explosion is very important, and is the main reason we (in the form that we are in) are around today, and why we have a technological civilization.

All of the atoms heavier elements (iron and heavier) all around, and even inside of you, were created from a supernova explosion. Those molecules of iron in your blood were once inside a star. In fact, any element heavier than hydrogen, helium, and lithium (the three lightest elements) were made inside of stars. The pressures required to fuse those lighter atoms together to form heavier atoms such as oxygen and carbon could have only been achieved (for the most part) inside of a star; and the pressures required for the heaviest of atoms could only be achieved by the force of a supernova blast.

So the raw material “stuff” inside of the stellar nursery nebula where our Sun was born was once inside an earlier generation of stars that were long dead prior to our solar system’s formation. That’s why our Sun is said to be a third generation star. There were probably at least two generations of stars that came before our sun that contributed the “stuff” that we all formed from. That’s why Carl Sagan was being quite literal when he famously said:

"We are made of star-stuff"



Can we find our Sun’s siblings? Are they still near us? Can we even find our Sun’s and solar system’s birthplace? The birthplace of the sun is probably long gone (dispersed/dissolved billions of years ago), but some scientist think they can track where the Sun’s siblings may be:

Abstract
The anomalous chemical abundances and the structure of the Edgeworth–Kuiper belt observed in the solar system constrain the initial mass and radius of the star cluster in which the Sun was born to M 500–3000M☉ and R 1–3 pc. When the cluster dissolved, the siblings of the Sun dispersed through the galaxy, but they remained on a similar orbit around the Galactic center. Today these stars hide among the field stars, but 10–60 of them are still present within a distance of ~100 pc. These siblings of the Sun can be identified by accurate measurements of their chemical abundances, positions, and their velocities. Finding even a few will strongly constrain the parameters of the parental star cluster and the location in the Galaxy where we were born.

Soucre: The Lost Siblings of the Sun

If the raw materials that went into making our solar system’s rocky planets and moons, and that went into allowing life to form on at least one of those planets, then if there are other sisters of the Sun out there that formed in a similar manner – AND formed from the same raw materials that allowed life to flourish on Earth, then perhaps those sisters of the Sun have similar solar systems that are similarly hospitable to life:

When the sun was a baby, some 4.5 billion years ago, it was nourished in the same stellar nursery as thousands of other baby stars. After a billion years, the cluster of young stars went their own ways, dispersing throughout interstellar space.
But, like any family, these stars have a lot in common. And like nursery mates here on Earth, they may have shared some germs and viruses during their formative years when they were in close proximity. But in this case, "cosmic chicken pox" may have formed the building blocks of life that eventually flourished on Earth. If there's life on Earth, might there be life on the planets that formed around our sun's siblings?

Source:
Search for Sun's Sibling Could Find Life's Cousin


Anyway, I've always found Carl Sagan's words "We are made of star-stuff" can make me feel extremely philosophical about my existence. The idea that the atoms inside of my body were formed together inside of a star makes the universe seem less of a place "out there" and more of a part of a holistic universe that has a deep formative connection, but at the same time (and seemingly contrary) it makes me realize Earth and humans are just a miniscule part of that holistic universe -- in both place AND time.

It's also amazing to think that in the 4.5 billion years that have past since our solar system formed along with (possibly) hundreds or thousands of other similar systems that those similar systems have all gone their separate ways throughout the galaxy.

Just maybe the IRAS did take a pictue of one sibling....a red dwarf in close proximity......though we don't hear about that from the PTB anymore do we?

originally posted by: stirling
Just maybe the IRAS did take a pictue of one sibling....a red dwarf in close proximity......though we don't hear about that from the PTB anymore do we?

While that potential object announced by the IRAS team in 1983 may or may not have been a red dwarf (further investigation found that it was not a red dwarf or other object close the Earth), the Sun's sisters will not necessarily be close to the Sun. They have had several billion years to drift relatively far away from us. The closest known stars to the Sun (such as Alpha Cenaturi) are not necessarily stars that came from the same stellar nursery as the Sun.

According to Simon F. Portegies Zwart of the University of Amsterdam, while many of the sun's siblings have drifted far out into depths of the galaxy, some of those stars may still be relatively close (within 300 light years) and still traveling along a path through the galaxy roughly parallel to us. Another clue into finding out whether or not a star is a sister of the Sun would be its composition; if it came from the same place, and made from the same raw materials, then it would probably have a similar composition (ratios of elements).

Great thread. S+F

The idea of being able to locate one of the Sun's siblings is an intriguing one and is kinda like the astronomical search for a needle in a haystack.

That's because all the stars in our galaxy are moving around the center and interacting gravitationally with each other when they come into close proximity.

The Sun's and its siblings have circled the Milky Way Galaxy many time since its birth. We can even calculate about how many times it has (roughly).

You see our Sun and the Solar System move around the Galaxy at 828,000 km/hr (about 515,000 mph).

But even at that high rate, it still takes us about 230 million years to make one complete orbit around the Milky Way

The Milky Way is 13.2 billion years old.

So....

13.2 billion / 230 million = 60

Our solar system and any siblings have orbited the galaxy about 60 times since birth from that stellar nursery.

However, with each orbit our Sun and the other siblings interact with different stars which weren't born from that nebula and these interactions cause them to take on slightly different trajectories, speed up or slow down their motion around the Milky Way.

So we're not all moving through the Galaxy at the same rate as we were 60 orbits ago.

For that reason it is very hard to find which stars were born with the Sun because they are likely distributed all throughout the galaxy.

Some perhaps may be on the entire other side of the Milky Way, beyond the galactic center.

I made a horrible, braindead mistake above.

Obviously our solar system is 4.5 billion years old but there could have been stars which formed out of the same stellar nursery as our Sun which are older.

So 4.5 billion / 230 million = 19.5 times our Solar System has gone around the Milky Way Galaxy.

Any older siblings will have gone around slightly more, but no where near 60 times.

That said, the rest of what I posted is correct. Due to interactions its very hard to track these stars down.

a reply to: Soylent Green Is People

I think there is some hypothetical data that implies our Sun does indeed have a companion star. Apparently a Red Dwarf or Brown Dwarf star that's orbiting beyond the Oort cloud. Call it Nemesis/Nibiru or what ever else point is that there is evidence to suggest something big is out there at a distance of 95,000AU.

Is it our Suns sister, who knows? Sure would be interesting to find out! And we will never accomplish that until we actually go there.

en.wikipedia.org...(hypothetical_star)

space.about.com...

originally posted by: andy06shake
a reply to: Soylent Green Is People

I think there is some hypothetical data that implies our Sun does indeed have a companion star. Apparently a Red Dwarf or Brown Dwarf star that's orbiting beyond the Oort cloud. Call it Nemesis/Nibiru or what ever else point is that there is evidence to suggest something big is out there at a distance of 95,000AU.

Is it our Suns sister, who knows? Sure would be interesting to find out! And we will never accomplish that until we actually go there.

en.wikipedia.org...(hypothetical_star)

space.about.com...

Data from 2MASS ruled out any red dwarfs closer than 6 light years from the Solar System

Data from the WISE spacecraft ruled out any brown dwarfs less than 5 light years from the Solar System.

SEE: Jet Propulsion Laboratory - NASA's WISE Survey Finds Thousands of New Stars, But No 'Planet X'

We can put the Niburu ideas to bed. They are now and have always been pure fantasy.

After searching hundreds of millions of objects across our sky, NASA's Wide-Field Infrared Survey Explorer (WISE) has turned up no evidence of the hypothesized celestial body in our solar system commonly dubbed "Planet X."

Researchers previously had theorized about the existence of this large, but unseen celestial body, suspected to lie somewhere beyond the orbit of Pluto. In addition to "Planet X," the body had garnered other nicknames, including "Nemesis" and "Tyche."

This recent study, which involved an examination of WISE data covering the entire sky in infrared light, found no object the size of Saturn or larger exists out to a distance of 10,000 astronomical units (au), and no object larger than Jupiter exists out to 26,000 au. One astronomical unit equals 93 million miles. Earth is 1 au, and Pluto about 40 au, from the sun.

"The outer solar system probably does not contain a large gas giant planet, or a small, companion star," said Kevin Luhman of the Center for Exoplanets and Habitable Worlds at Penn State University, University Park, Pa., author of a paper in the Astrophysical Journal describing the results.

While I'm not necessarily a believer that panspermia is the origin of life on Earth (although I think it is a possible origin of Earth life), I do believe that the specific features that made our solar system a fertile place for live to thrive in at least one place in this solar system could be common in other solar systems. If these sister stars of the Sun (and their solar systems) were created in the same place and out of the same raw materials, then those other solar systems, too, may be fertile places for life to thrive.

Some of the primordial dust and "stuff" that went into making our solar system 4.5 billion years ago still exists. Comets and asteroids are the leftover stuff that went into building our solar system, and astronomers think that the material still in those comets and asteroids today have not changed that much in 4.5 billion years.

NASA "Stardust" space probe was sent to rendezvous with a Comet Wild 2 (pronounced "Vildt") and return a sample of the comet's dust to Earth. After the sample return capsule returned to Earth in 2006, the dust was analyzed and found to contain organic molecules -- not life itself, but the building blocks of life.

NASA "Stardust": Comet Organics May Be the Original Material of an Early Solar System

This first in-situ collection of cosmic dust for analysis showed that our solar system is almost built for life as we know it -- or at least it is built with the materials needed for that life to thrive. It would seem likely that the solar systems associated with at least some of the siblings of the Sun would also have these same organic molecules in their primordial dust, which would make those solar system could also be built with the materials needed for life to thrive.

originally posted by: Soylent Green Is People
While I'm not necessarily a believer that panspermia is the origin of life on Earth (although I think it is a possible origin of Earth life), I do believe that the specific features that made our solar system a fertile place for live to thrive in at least one place in this solar system could be common in other solar systems. If these sister stars of the Sun (and their solar systems) were created in the same place and out of the same raw materials, then those other solar systems, too, may be fertile places for life to thrive.

Yep. The whole field of Astrobiology was borne out of this realization 30 years ago or so. Organics are common in space and were first observed in interstellar dust clouds and stellar nurseries.

That's why we have astrobiology now. The realization that the stuff we're made out of isn't so special, and we're probably not either.

Funnily enough, the latest COSMOS episode talked about stars being born in clusters, and that the Sun's "siblings" have long since spread throughout the galaxy.

originally posted by: wildespace
Funnily enough, the latest COSMOS episode talked about stars being born in clusters, and that the Sun's "siblings" have long since spread throughout the galaxy.

I recommend anyone who reads this forum to watch Cosmos. I'm very happy with how the show has gone. I bet Carl Sagan would be very proud of it.