Astronomy & Space Exploration

[frostbite]

Different topic. The largest black hole we know about so far.

The whole channel is very interesting, created by a German. If you are interested in science, check it out!

https://kurzgesagt.org/about/

 

[Cheimoon]

Did you see the article about the parasites in the permafrost, entirely alive, after tens of thousands of years? By definition two things: one, we can assume that such organisms (moon/mars) can survive for incredible periods of time even after "life" is said to have disappeared (if it was present in Earth-like form); two, we cannot have any immunity, like-for-like, to that which has been kept out of the foodchain for such a vast period of time. Forget about Mars or the Moon, when that Permafrost starts melting, you have to wonder what kinds of virals and microbials, the second being among the most abundant of all lifeforms on the planet, have survived from previous geological eras. What was the Mammoth carrying? Or extinct bird species? All kinds of weird bacteria definitely exist, in-vitro (cryogenic), beneath that layer. One more reason we do not want it to melt. Aside from us all being dead when it does.

Yeah, those things are interesting... Nothing to do with astronomy though!

 

[neverdie]

Yeah, those things are interesting... Nothing to do with astronomy though!

Except for the icecaps on the moon/mars and various other orbital bodies where "life" may not be now, as thought of commonly, but may have residual traces going by earth's own surprises.

 

[giggs-beckham]

Also the study of extremophiles is used to widen our scope for how different exoplanetarty environments could potentially harbour life, widening our expectations

 

[calodo2003]

This blows my mind.

 

[Buster15]

https://www.bbc.co.uk/news/science-environment-66950930

Wow. Some scientists believe that we may discover signs of alien life within our lifetimes and maybe in the next few years.
But we must remember that alien lifeforms can be in a very wide range of possibilities.
From single cell bacteria up to much more complex species.

And in this article, the Universe is described as Infinite which may be so.
And therefore with infinite number of stars and planets.

 

[stefan92]

https://www.bbc.co.uk/news/science-environment-66950930

Wow. Some scientists believe that we may discover signs of alien life within our lifetimes and maybe in the next few years.
But we must remember that alien lifeforms can be in a very wide range of possibilities.
From single cell bacteria up to much more complex species.

And in this article, the Universe is described as Infinite which may be so.
And therefore with infinite number of stars and planets.

JWST and ELT both have or will have the capability to detect planetary atmospheric spectrums and they work in different wavelengths, so we will have the possibility to analyze planetary atmospheres in good enough detail that strong biospheric signals (like earth' 21% oxygen) can be identified. We just have to be lucky that we look in the right direction.

 

[Raoul]

Different topic. The largest black hole we know about so far.

The whole channel is very interesting, created by a German. If you are interested in science, check it out!

https://kurzgesagt.org/about/

Interesting. I usually watch the SEA channel, which makes pretty good videos.

 

[giggs-beckham]

https://www.bbc.co.uk/news/science-environment-66950930

Wow. Some scientists believe that we may discover signs of alien life within our lifetimes and maybe in the next few years.
But we must remember that alien lifeforms can be in a very wide range of possibilities.
From single cell bacteria up to much more complex species.

And in this article, the Universe is described as Infinite which may be so.
And therefore with infinite number of stars and planets.

Surely at very large distances individual stars and their accompanying planets would be too faint to observe.
Re the life detection soon debate, we live in hope now more than ever don't we?

 

[Buster15]

JWST and ELT both have or will have the capability to detect planetary atmospheric spectrums and they work in different wavelengths, so we will have the possibility to analyze planetary atmospheres in good enough detail that strong biospheric signals (like earth' 21% oxygen) can be identified. We just have to be lucky that we look in the right direction.

I guess that oxygen in an atmosphere, especially at such levels would have to have been created by things like photosynthesis and not during the formation of a planet.
It seems that they are looking for planets in the so called Goldilocks Zone where this and water could be there.

 

[Buster15]

Surely at very large distances individual stars and their accompanying planets would be too faint to observe.
Re the life detection soon debate, we live in hope now more than ever don't we?

Yes indeed. Although the JWST seems to be providing incredible amounts of information by using its Infrared capability detecting faint colours.

 

[dinostar77]

Gotta love JWST, redefining what we know about astronomy on a almost weekly basis.

James Webb telescope makes 'JuMBO' discovery of planet-like objects in Orion

Jupiter-sized "planets" free-floating in space, unconnected to any star, have been spotted by the James Webb Space Telescope (JWST).

What's intriguing about the discovery is that these objects appear to be moving in pairs. Astronomers are currently struggling to explain them.

The telescope observed about 40 pairs in a fabulously detailed new survey of the famous Orion Nebula.

They've been nicknamed Jupiter Mass Binary Objects, or "JuMBOs" for short.

https://www.bbc.com/news/science-environment-66974738

 

[Big Andy]

Gotta love JWST, redefining what we know about astronomy on a almost weekly basis.

James Webb telescope makes 'JuMBO' discovery of planet-like objects in Orion

Jupiter-sized "planets" free-floating in space, unconnected to any star, have been spotted by the James Webb Space Telescope (JWST).

What's intriguing about the discovery is that these objects appear to be moving in pairs. Astronomers are currently struggling to explain them.

The telescope observed about 40 pairs in a fabulously detailed new survey of the famous Orion Nebula.

They've been nicknamed Jupiter Mass Binary Objects, or "JuMBOs" for short.

https://www.bbc.com/news/science-environment-66974738

Pluto will be fuming at this. Downgraded to dwarf and then Jumbo’s come along

 

[Carolina Red]

Just watched the international space station fly over. That’s always pretty cool. The neighbors have young kids & I got to point it out to them, so seeing their excitement about it made it even cooler.

 

[Raoul]

 

[rcoobc]

Could Modified Gravity Be the Answer to Planet 9?

As students advance to higher and higher physics courses, they eventually learn that the simple Newtonian dynamics they learned about in early classes aren’t completely accurate models for understanding the universe. If things get too big or fast, they fall into the realm of relativity, or if they get too small, they get caught up in quantum mechanics. However, simple Newtonian dynamics does the trick for things ranging from how a baseball flies to how planets orbit the Sun.

At least until it doesn’t. Recently, some astronomers have suggested that they would have to modify the Newtonian dynamics they know so well to understand more complex events. Modified Newtonian Dynamics (or MOND) theory has already been proven accurate for things like understanding galactic rotation. But what about using it closer to home?

Many lay people, and even many astronomers, believe that there is a Planet 9 out there. As proof, they point to the orbital mechanics of a class of Kuiper Belt Objects (KBOs). Tracing these frozen asteroids throughout the solar system, it seems many of their movement could be explained if there were a giant planet about five times the size of Earth and about 500 times farther away from the Sun.

....

But Katherine Brown of Hamilton College and her co-author Harsh Mathur of Case Western Reserve University think they have another plausible explanation. They believe MOND can explain why the orbital paths of these KBOs seem so strange compared to the rest of the bodies in the system.

https://www.universetoday.com/163533/could-modified-gravity-be-the-answer-to-planet-9/

The scientists plotted what would happen if the objects were being governed by a theory known as Modified Newtonian Dynamics or MOND. That suggests that Newton’s usual gravity only works up to a point – that in the outer regions of galaxies, for instance, gravity behaves in unusual ways.

They found that the data lined up, and applying the MOND theory to the existing observations seemed to predict them exactly. “The alignment was striking,” said Professor Mathur.

https://www.independent.co.uk/space/planet-9-nine-solar-system-gravity-b2425533.html


Link to paper:

https://arxiv.org/pdf/2304.00576.pdf

And the conclusion

Historically, claimed gravitational anomalies in the solar system have almost invariably proven to be spurious under closer examination, albeit sometimes involving more than a century of debate and meticulous observation (Batygin et al. 2019; Standish 1993; Turyshev et al. 2012).

But they have also led to the discovery of Neptune and helped establish general relativity.

It is possible that the Kuiper belt anomalies are evidence of Planet Nine, or that they are spurious (Shankman et al. 2017; Lawler et al. 2017; Bernardinelli et al. 2020b; Napier et al. 2021);

alternatively they may be evidence for a modification of Newtonian gravity

Very interesting, even if the paper literally says that MOND is just one of several possibilities to explain the anomalies that are being used as evidence for "Planet 9"

 

[dinostar77]

Could Modified Gravity Be the Answer to Planet 9?



https://www.universetoday.com/163533/could-modified-gravity-be-the-answer-to-planet-9/


https://www.independent.co.uk/space/planet-9-nine-solar-system-gravity-b2425533.html


Link to paper:

https://arxiv.org/pdf/2304.00576.pdf

And the conclusion




Very interesting, even if the paper literally says that MOND is just one of several possibilities to explain the anomalies that are being used as evidence for "Planet 9"

interesting post. thanks.

Was it Socrates who was supposed to have said, "the more i learn, the less i know"? That would be apt for our understanding of the universe as we continue to study it.

So what causes a LFBOT* to occur 50,000 light years from a spiral galaxy and 15,000 away from a smaller galaxy? Researchers are puzzled. Luminousity 100 stronger than a supernova. Only one LFBOT detected per year.

Lots of guess work going on...

https://www.universetoday.com/163555/hubble-sees-a-mysterious-flash-in-between-galaxies/

*LFBOT (luminous fast blue optical)

 

[nimic]

 

[Vault Dweller]

Love that channel.

 

[MrMarcello]

65 hinted at previous life in the universe via ancient advanced civilization transporting beings through space and crashed on Earth, 65000000 BCE.

 

[Counterfactual]

Loved that. Thanks for sharing it. I always thought the panspermia idea was more likely than the spontaneous evolution of life here, and this gives it greater plausibility.

 

[That'sHernandez]

For the entire universe to be the temperature conducive to life radiation levels and concentrations would have been very high, which would limit the ability for life to flourish without protection via magnetic fields and atmospheres. Simply counting RNA lengths backwards seems like it's potentially finding a pattern in something (which the human brain loves to do) where there potentially is none.

Love the idea but I'm sceptical.

 

[Pintu]

 

[giggs-beckham]

They've been finding amino acids in space rocks for years

 

[dinostar77]

A weird one, White Holes. The things that einstien predicted but we've never found.

White Holes: Inside the Horizon review – Carlo Rovelli turns time on its head

https://www.theguardian.com/books/2...rlo-rovelli-review-black-hole-quantum-physics

"...Rovelli exploits to suggest that the star at the centre of a black hole, trying to collapse away to nothing, might reach a point at which quantum uncertainty allows it to “bounce” backward through time and become a white hole...."

Hmmm.......

 

[Raoul]

A weird one, White Holes. The things that einstien predicted but we've never found.

White Holes: Inside the Horizon review – Carlo Rovelli turns time on its head

https://www.theguardian.com/books/2...rlo-rovelli-review-black-hole-quantum-physics

"...Rovelli exploits to suggest that the star at the centre of a black hole, trying to collapse away to nothing, might reach a point at which quantum uncertainty allows it to “bounce” backward through time and become a white hole...."

Hmmm.......

They are still hypothetical apparently, much like gravitons, tachyons, and several others.

 

[Stack]

Love this thread, my favourite thread to see bumped

 

[nimic]

They are still hypothetical apparently, much like gravitons, tachyons, and several others.

Wormholes, etc.

 

[Salt Bailly]

Love this thread, my favourite thread to see bumped

It's between this and the Longest continually numbered posts in a row record attempt thread.

 

[giggs-beckham]

A weird one, White Holes. The things that einstien predicted but we've never found.

White Holes: Inside the Horizon review – Carlo Rovelli turns time on its head

https://www.theguardian.com/books/2...rlo-rovelli-review-black-hole-quantum-physics

"...Rovelli exploits to suggest that the star at the centre of a black hole, trying to collapse away to nothing, might reach a point at which quantum uncertainty allows it to “bounce” backward through time and become a white hole...."

Hmmm.......

The big bang is thought to be from a white hole, an infinitely dense singularity travelling outwards. I'm not sure we'll ever know really about the first seconds (Plancktime) of the universe, theoretical physics it shall remain.

 

[slyadams]

Surely at very large distances individual stars and their accompanying planets would be too faint to observe.
Re the life detection soon debate, we live in hope now more than ever don't we?

Yes and no. So much of what we observe and deduce from the universe comes from observations (mostly of light) and strong inference. As has been mentioned there are certain things that are strongly indicative of life. If we found a planet in a goldilocks zone with water vapour and high levels of oxygen (a highly reactive gas that, as far as we know can only exist in high proportions when continually generated by life) in the atmosphere we can start to infer the most likely source. We might never know for sure without more direct observations, but we'd get into the territory where a massive section of the community would dedicate itself to disproving that its life (e.g. similarly to when phosphene was detected on Venus). If those efforts start to flounder we can start to get excited.

Personally, I have a stroing suspicion that we will find evidence of life within the solar system in the next 50-100 years. The could be fossilized on somewhere like Mars or in the water oceans of the gas giants moons. If we do find such evidence the key thing is going to be determining if the source of that life is the same as on Earth (i.e. panspermia). If it is then we might be no closer to determining if life is common, if it rose independently we will know with almost certainty that life will be abundant in the universe.

 

[Buster15]

Yes and no. So much of what we observe and deduce from the universe comes from observations (mostly of light) and strong inference. As has been mentioned there are certain things that are strongly indicative of life. If we found a planet in a goldilocks zone with water vapour and high levels of oxygen (a highly reactive gas that, as far as we know can only exist in high proportions when continually generated by life) in the atmosphere we can start to infer the most likely source. We might never know for sure without more direct observations, but we'd get into the territory where a massive section of the community would dedicate itself to disproving that its life (e.g. similarly to when phosphene was detected on Venus). If those efforts start to flounder we can start to get excited.

Personally, I have a stroing suspicion that we will find evidence of life within the solar system in the next 50-100 years. The could be fossilized on somewhere like Mars or in the water oceans of the gas giants moons. If we do find such evidence the key thing is going to be determining if the source of that life is the same as on Earth (i.e. panspermia). If it is then we might be no closer to determining if life is common, if it rose independently we will know with almost certainty that life will be abundant in the universe.

Very interesting.
How do we know that the source of life on Earth is the result of Panspermia?

 

[stefan92]

Very interesting.
How do we know that the source of life on Earth is the result of Panspermia?

We will probably never now if Earth was seeded by Panspermia or if live from Earth seeded other planets in the solar system, but we would be able to prove relation, even at the most basic level. A strong indicator would be as similar genetic code. All live on Earth is using RNA (and DNA in more evolved lifeforms) using guanine, uracil (RNA only), adenine, cytosine and thymine (DNA only) and if we find live anywhere else in the universe that uses the same structure it would be an indicator for actual relation - there are a lot of organic molecules that form a chain structure beyond ribose and lot more nucleic acids beyond those five. So even a pretty similar lifeform could probably evolve but using a completely different genetic code (and then likely be unrelated)

 

[Buster15]

We will probably never now if Earth was seeded by Panspermia or if live from Earth seeded other planets in the solar system, but we would be able to prove relation, even at the most basic level. A strong indicator would be as similar genetic code. All live on Earth is using RNA (and DNA in more evolved lifeforms) using guanine, uracil (RNA only), adenine, cytosine and thymine (DNA only) and if we find live anywhere else in the universe that uses the same structure it would be an indicator for actual relation - there are a lot of organic molecules that form a chain structure beyond ribose and lot more nucleic acids beyond those five. So even a pretty similar lifeform could probably evolve but using a completely different genetic code (and then likely be unrelated)

Thank you so much for taking your time to respond in such an interesting way. That is fascinating and I will read it a few more times to fully understand it.
I have learnt so much from this thread.

 

[stefan92]

Thank you so much for taking your time to respond in such an interesting way. That is fascinating and I will read it a few more times to fully understand it.
I have learnt so much from this thread.

I'll happily add another thought to this: All life on earth is related to each other and can be traced back to a "large universal common ancestor" (LUCA). Science isn't very sure about how that looked, but it probably existed during the "RNA era" (so DNA evolved only to be used after this). Even further down in history there extremely likely has been a first universal common ancestor (FUCA) - all other descendants of which except LUCA died out, but though unlikely it is also possible that no branch deriving from FUCA died out, in which case FUCA and LUCA would be the same. If we would find other life in the solar system we could derive if it branched somewhere between FUCA and LUCA from our tree of life, in which case we wouldn't know if FUCA existed on Earth or if it originated on another body of the solar system (or even beyond) and only the LUCA branch of live arrived on Earth.

But even the existence of FUCA doesn't necessarily mean that life only evolved once on Earth. It is theoretically possible that multiple types of life developed on Earth and only one did survive the early days of our planet. So it is even possible that very early non-FUCA-related live existed on Earth, was transferred to for example Mars due to massive impact events launching rocks into space, and if we find it on Mars we would think it evolved there as we have no way to realize it actually evolved on Earth.

This scenario becomes especially possible if we assume that life developed before the Late Heavy Bombardement that probably sterilized (most of) the Earth. It seems unlikely that life as we know it really developed before the LHB, but as we are talking about life different then what we know today it increases the possibilites. However due to what happened over billions of years we will never be able to definitely find any fossils from that period so this will most likely stay speculation forever.

 

[slyadams]

Very interesting.
How do we know that the source of life on Earth is the result of Panspermia?

Right now we don't. If we don't find life anywhere else it becomes less likely as a possibility, but also less likely we could ever rule it in or out. In truth its hard to prove a negative. We could find 1000 other life forms that are completely different to the point we can be sure we aren't related to those, but that doesn't rule out there isn't a relative out there.

 

[Buster15]

I'll happily add another thought to this: All life on earth is related to each other and can be traced back to a "large universal common ancestor" (LUCA). Science isn't very sure about how that looked, but it probably existed during the "RNA era" (so DNA evolved only to be used after this). Even further down in history there extremely likely has been a first universal common ancestor (FUCA) - all other descendants of which except LUCA died out, but though unlikely it is also possible that no branch deriving from FUCA died out, in which case FUCA and LUCA would be the same. If we would find other life in the solar system we could derive if it branched somewhere between FUCA and LUCA from our tree of life, in which case we wouldn't know if FUCA existed on Earth or if it originated on another body of the solar system (or even beyond) and only the LUCA branch of live arrived on Earth.

But even the existence of FUCA doesn't necessarily mean that life only evolved once on Earth. It is theoretically possible that multiple types of life developed on Earth and only one did survive the early days of our planet. So it is even possible that very early non-FUCA-related live existed on Earth, was transferred to for example Mars due to massive impact events launching rocks into space, and if we find it on Mars we would think it evolved there as we have no way to realize it actually evolved on Earth.

This scenario becomes especially possible if we assume that life developed before the Late Heavy Bombardement that probably sterilized (most of) the Earth. It seems unlikely that life as we know it really developed before the LHB, but as we are talking about life different then what we know today it increases the possibilites. However due to what happened over billions of years we will never be able to definitely find any fossils from that period so this will most likely stay speculation forever.

Again my friend. I really do appreciate your inputs which I read with great interest. You are a very clever man.

 

[Buster15]

Right now we don't. If we don't find life anywhere else it becomes less likely as a possibility, but also less likely we could ever rule it in or out. In truth its hard to prove a negative. We could find 1000 other life forms that are completely different to the point we can be sure we aren't related to those, but that doesn't rule out there isn't a relative out there.

Thank you for this. I absolutely love reading this type of thing.

 

[stefan92]

Again my friend. I really do appreciate your inputs which I read with great interest. You are a very clever man.

Thank you, but I'm just interested in this stuff

 

[Buster15]

Thank you, but I'm just interested in this stuff

Do you have a scientific background.
I have always been interested in Physics and especially anything to do with the Cosmos.
The only thing that lost me completely was String Theory.
I like things that I can at least visualise.

There are some really clever people who post on this thread.