Could our galaxy be made of black holes?

[masbtt]

I have the idea that dark matter doesnt exist and instead, our galaxy is made mainly of black holes and the stars make only a small part of his mass.

Is that a foolish idea or can it be possible?

Maybe, when they are mapping the dark matter based on light bending, what they are doing is mapping the density of black holes and other interestelar stuff like planetos, that could exist by billions.

 

[MeteorWayne]

Hi, welcome to Space.com

Well, your idea isn't foolish, but it almost certainly isn't right either

While there may be a few scattered small black holes in the galaxy, and of course the massive one at the center, galactic blach holes would have been detected by their individual gravitational lensing. In fact, most dark matter is detected surrounding other galaxies; we're a bit to close to the diffuse (and undetectable by other than gravity) source in our own to find discrete sources.

Wayne

 

[Boris_Badenov]

What is a "Planeto"?

 

[yevaud]

Planeto is not a word. I think what he's trying to say is "Planetesimal?"

 

[masbtt]

Thank you for your replies. Whithout knowing so much it seemed to me that it would be an easiest way.

A planeto, I think, is a planet that is not orbiting a star, and it is located therefor, in the interestellar space, but maybe I have chosen a wrong term, because I think a planeto is a planet that has scaped of his orbit, and is wandering in space.

What i mean is planets naturally born in the interestellar space by the same proces of agregation of matter that formed the stars. I think this kind of objects could exist by billions in our galaxy, objects like jupiter with tens of satelite worlds that dont need to have been formed around a star.

I read once an article saying that those worlds could be the most common places where life can exist because under certain conditions not necesarilly need to be frozen and those worlds dont need an ozone layer or a magnetic field like earth to protect life from letal radiations from the sun..

But on the other hand I think that most of the energetic processes that happen on earth are possible because of the sun
enegy that came to us, so I dont know , but it would be fantastic.

 

[neilsox]

A trillon (average Earth Mass) planets orbiting our galaxy, instead of a star would not add enough mass to replace dark matter. A trillion of them (evenly distributed) would mean a pass though our Oort cloud about once? per century. Since we have not identified even one (for sure) yet, likely the total in our galaxy is less than one trillion.
A billion black holes all ten solar mass, orbiting without a companion star, would possibly not produce noticeable lensing, unless closer than ten light years = not enough mass to replace dark matter. Such bodies may supplement dark matter, but probably cannot replace dark matter. The mainstream theory may have a serious error, making almost anything possible. Neil

 

[SpaceTas]

Massive compact halo objects Machos (free floating planets, cool white dwarfs, netron stars and black holes) were postulated as the source of some of the dark matter. There was a series of surveys (MACHO, EROS) that looked for the micro-lensing effect from these objects as they passed in the line of sight to stars in the large and small Magellanic clouds. Not enough events were found to explain the dark matter as massive compact objects. The alternative Weakly Interacting Massive Particles (WIMPS = exotic sub-atomic particles and/or neutrinos with mass) are still a viable option for dark matter.
Modifications on standard gravity (eg MOND theory) are another possibility.

There are on going microlensing surveys (OGLE and MOA) looking toward the center of the galaxy. In 10+ years of searching these groups and follow up groups such as PLANET have only found 1 possible black hole. They have found several planets, brown dwarfs in orbit about low mass stars.

Microlensing: When a foreground star (and massive object) passes in front of a background star, the gravity of the foreground star acts as a lens magnifying the background star, so that it's apparent brightness increases. As the alignment gets first better then worse the brightness of the background star first increases then decreases in a smooth fashion. The mass of the foreground object can sometimes be measured using secondary effects. If the foreground object (usually a low mass star, M dwarf) has a companion (star or planet) then the brightness does not follow a simple smooth curve, but has multiple peaks, and/or bends. Potentially (with a lot of luck) an earth mass planet could be found. So far 13 planets have been found this way including a 5.5 Earth mass planet. More planets are found every year.

 

[noblackhole]

Not a chance. The black hole is a fairy tale. And so nobody has ever found one (although the astrophysical scientists falsely claim that they have found them all over the place). Galaxies are not composed of fairy tales.

 

[yevaud]

A planeto, I think, is a planet that is not orbiting a star, and it is located therefor, in the interestellar space, but maybe I have chosen a wrong term, because I think a planeto is a planet that has scaped of his orbit, and is wandering in space.

My recollection is, those are referred to as "Free Planets" or "Rogue Planets."

 

[BoJangles2]

Not a chance. The black hole is a fairy tale. And so nobody has ever found one (although the astrophysical scientists falsely claim that they have found them all over the place). Galaxies are not composed of fairy tales.

This is a place of science (consensus of understanding) not pseudo science, I shudder to think how many people you will delude with that back-seater-statement. Unless you’re going to write you own paper (or have someone else’s paper) that has the consensus of scientific opinion, keep it to yourself.

People come here to learn the accepted sciences, not be bewildered by that sort of dribble.

I'm sorry if that sounded harsh, but it’s tough love and directed at anyone who is trying to learn what is being taught at reputable institutions.

K thanks.