Evidence for ET?

[Gawdzilla Sama]

I've seen speculation that planets could form without being in orbit around a star. That would mean that smaller objects could be formed in interstellar space as well.

That would be totally different. The sort of “planet” that are believed to form independently of any Star are really miniature star in their own right in terms of composition, just too small to actual ignite or sustain thermal nuclear fussion like normal star.  They are still enormous objects, likely on average much more massive than Jupiter.

I am to understand that matter doesn't conglomerate in progressively larger chunks? That the smallest such accumulated mass would "likely on average much more massive than Jupiter"?

[Jehanne]

That would be totally different. The sort of “planet” that are believed to form independently of any Star are really miniature star in their own right in terms of composition, just too small to actual ignite or sustain thermal nuclear fussion like normal star.  They are still enormous objects, likely on average much more massive than Jupiter.

I am to understand that matter doesn't conglomerate in progressively larger chunks? That the smallest such accumulated mass would "likely on average much more massive than Jupiter"?

Jupiter emits twice as much EM as it absorbs from the Sun. If there were large numbers of Jupiter-sized objects in interstellar spaces (MACHOS), they would have been detected via gravitational lensing, occultations, etc. Such objects have not been found in large numbers. Ergo, most large objects form around stars.

[Anomalocaris]

That would be totally different. The sort of “planet” that are believed to form independently of any Star are really miniature star in their own right in terms of composition, just too small to actual ignite or sustain thermal nuclear fussion like normal star.  They are still enormous objects, likely on average much more massive than Jupiter.

I am to understand that matter doesn't conglomerate in progressively larger chunks? That the smallest such accumulated mass would "likely on average much more massive than Jupiter"?

Matter in interstellar medium are only likely to stick together and form sizeable macroscopic chunks if the interstellar medium is already being concentrated by being caught in the gravity well of local over-densities in the interstellar medium. The total mass of local over-density in interstellar medium required to be able to pull additional interstellar material towards itself and concentrate them is many times the mass of Jupiter.

If the process of runaway gravitational collapse is not there to concentrate interstellar matters, then because particles in interstellar medium are extremely far apart and have random motions, the chance of random collision resulting in particles sticking together to form larger particles until the result reach asteroid size is infinitesimal.

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I am to understand that matter doesn't conglomerate in progressively larger chunks? That the smallest such accumulated mass would "likely on average much more massive than Jupiter"?

Jupiter emits twice as much EM as it absorbs from the Sun.  If there were large numbers of Jupiter-sized objects in interstellar spaces (MACHOS), they would have been detected via gravitational lensing, occultations, etc.  Such objects have not been found in large numbers.  Ergo, most large objects form around stars.

Machos suppose a truly enormous numbers of compact planet like objects floating through Milky Way sufficient in total to rival and exceed the mass of all the stars in Milky Way and make up a major portion of the missing matter known to effect milky way’s rotation.

I think that scenario is discredited.

But the notion that Milky Way still has a large number of free floating planets similar in head count to the total number, but not mass, of stars in the Milky Way rather gained support. There have been gravitation lensing events attributed to free floating planets. This does not contradict the notion that most large objects form around stars. Most of the free floating planets could have formed around stars and then subsequently ejected from their system of birth.

[Gawdzilla Sama]

I am to understand that matter doesn't conglomerate in progressively larger chunks? That the smallest such accumulated mass would "likely on average much more massive than Jupiter"?

Jupiter emits twice as much EM as it absorbs from the Sun.  If there were large numbers of Jupiter-sized objects in interstellar spaces (MACHOS), they would have been detected via gravitational lensing, occultations, etc.  Such objects have not been found in large numbers.  Ergo, most large objects form around stars.

Have you counted them?

[Anomalocaris]

Jupiter emits twice as much EM as it absorbs from the Sun.  If there were large numbers of Jupiter-sized objects in interstellar spaces (MACHOS), they would have been detected via gravitational lensing, occultations, etc.  Such objects have not been found in large numbers.  Ergo, most large objects form around stars.

Have you counted them?

Is this the same idiocy as “were you there”?

[Gawdzilla Sama]

Have you counted them?

Is this the same idiocy as “were you there”?

Just wondering if you had any kind, any at all, of a basis for your claims.

[Anomalocaris]

Is this the same idiocy as “were you there”?

Just wondering if you had any kind, any at all, of a basis for your claims.

If I am not mistaken, I don’t think anyone has made a bottom up census of free floating planets because there is a huge gap in difficulty between finding exoplanets orbiting stars and objects other than stars free floating in interstellar space. We have the theoretical capacity to detect free floating planets only under special circumstances. For example if there is a Jupiter like body half way between the sun and alpha Centauri, we would be hard pressed to detect it even if we know where to look. We also don’t have widely accepted basis to extrapolate from the number we can potentially detect to how many are actually there.

So we only have top down estimates, based on our understanding of interstellar condition, calculated chances of objects forming, and estimate chances of planets formed around stars being ejected.

[Gawdzilla Sama]

Ah, you don't have any basis then. Got it.

[Anomalocaris]

No, we have as much basis as is available From current observations of the properties of the interest stellar medium. The basis is not As firm as might be wished. But unless you have some private evidence or observations that you have not chosen to share, then you ignore what bases are available at your own peril.

[Gawdzilla Sama]

LOL.

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