Kade Rystalmane
Well-known member
What evidence is there for new star formation?
We have photos of it happening for one thing.What evidence is there for new star formation?
Stellar Nursery
NASA's Spitzer Space Telescope captured a glowing stellar nursery within a dark globule that reveals the birth of new protostars, or embryonic stars, and young stars never before seen.
The Elephant's Trunk Nebula is an elongated dark globule within the emission nebula IC 1396 in the constellation of Cepheus. Within the globule, a half dozen newly discovered protostars are easily discernible as the bright red-tinted objects, mostly along the southern rim of the globule. These were previously undetected at visible wavelengths due to obscuration by the thick cloud ('globule body') and by dust surrounding the newly forming stars. The newborn stars form in the dense gas because of compression by the wind and radiation from a nearby massive star (located outside the field of view to the left). The winds from this unseen star are also responsible for producing the spectacular filamentary appearance of the globule itself, which resembles that of a flying dragon
Direct observationWhat evidence is there for new star formation?
What would you accept as "real evidence"? We have visual confirmation of stars in all different stages of formation, from the beginning dust cloud condensation all the way through ignition. The situation is analogous to having photos of all different stages of the growth of a redwood tree, from pine cone to seedling to sapling to immature tree to mature tree. No one is ever going to witness the entire 500 year long process in real time from start to finish.So far, none of these responses has actually provided real evidence.
So far, none of these responses has actually provided real evidence. Allegedly the process to form a new star takes about a million years according to the scientists that talk about the process. If this is true, how can we say with any credibility (much less certainty) that what is being observed is star "formation" given that we have only been studying stellar life cycles for less than .02% of that amount of time? In other words, what is the actual evidence beyond the say-so of the scientific clergy?
For instance, looking at the Elephant's Trunk nebula example, we have observed previously unobserved stellar objects. They are referred to as proto-stars or newborn stars, but how do we know that? Or are scientists inferring it without it being a necessary implication of what has been observed? Perhaps they are stellar objects that we simply haven't seen before in the brief time we've had the technology to do so "due to obscuration by the thick cloud ('globule body') and by dust surrounding" them and because older technology wasn't up to the job. Just because we started observing them recently doesn't mean they weren't there before, only that we couldn't see them.
Which notes? What is the context of these notes?From my notes:
Which notes? What is the context of these notes?
And these statements from the book were observations taken over time?From my theoretical studies in "An Introduction to Modern Astrophysics".
I was able to find many measurements dating back to 1987 and '88 and studies continue to this day.And these statements from the book were observations taken over time?
Could you explain how these measurements show that the Bok Globules were at one point not stars and then became stars?I was able to find many measurements dating back to 1987 and '88 and studies continue to this day.
B335 is considered an ideal protostellar core because it is free from a variety of large molecular cloud complexes and other nearby protostars. It makes an excellent natural laboratory for testing simple models.
Congratulations, you have just proved the sun is not possible - it is basically just hydrogen under pressure.I'd like to approach this from a different vector by addressing some known physics.
1. Gasses expand to fill available space.
2. Nebulae are gasses that are many light years across and very sparse (10^3 particles/cu cm) and cold (~100K).
3. As gasses are condensed, pressure increases, making them "want" to expand even moreso.
4. Gravity is by far the weakest of forces (G = 6.67x10^(-11) and is diminished by the inverse square law (1/d^2).
5. Electromagnetism is 134 quadrillion times stronger than gravity (k_e = 9.00x10^9) and is also diminished by the inverse square law (1/d^2).
6. Nebulae are said to be formed by a rapidly expanding (exploding) star (supernova).
Knowing these things, why would we conclude that these sparse gases ever could or would contract into a star? ...
Expanding gasses from an exploded star reversing direction under these conditions to form new stars is a different scenario than a star that already exists and is burning through its fuel. These aren't the same conditions and so we can't reject or accept the one based on the other.Congratulations, you have just proved the sun is not possible - it is basically just hydrogen under pressure.
Either that, or your hypothesis is faulty.
Nevertheless, your objections apply to the sun. It is a huge mass of hydrogen under extreme pressure. If you are right, those gases will quickly dissipate.Expanding gasses from an exploded star reversing direction under these conditions to form new stars is a different scenario than a star that already exists and is burning through its fuel. These aren't the same conditions and so we can't reject or accept the one based on the other.
I'm asking for hard evidence for star formation here, and so far inertia is the only one willing to engage on an academic level (which I greatly appreciate).
Could you explain how these measurements show that the Bok Globules were at one point not stars and then became stars?
Again, these are not the same conditions and scenarios. Yes, those statements do apply in context, but a giant gas cloud spread over light years is not comparable to a thin layer (approximately 100km thick) of atmosphere attracted to the earth which has a radius of ~6371km and a mass that is more than a million times greater. The atmospheric pressure is insufficient to generate enough velocity in the majority of the atmosphere and only those at the very top have enough energy and velocity to reach escape velocity at all.Nevertheless, your objections apply to the sun. It is a huge mass of hydrogen under extreme pressure. If you are right, those gases will quickly dissipate.
The gas giants are other examples. They are virtually all hydrogen, and some how the gravity is strong enough to keep the hydrogen there.
In fact, just on Earth, we have air around us that is held here by this incredibly weak force - gravity.
So from 1987 to 2021, observations show that this non-star, non-nebula celestial body has transformed from or into something else?Measurements since 1987 show that the protostar within B335 is currently collapsing, but not at a "freefall rate". More recently, organic molecules have been discovered within a compact region around 10 AU of the core. The source is from a carbon chain reaction, a well-known nuclear process.
So from 1987 to 2021, observations show that this non-star, non-nebula celestial body has transformed from or into something else?
Knowing these things, why would we conclude that these sparse gases ever could or would contract into a star?