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Astronomy / The Universe


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maroonlegions
12 hours ago, deesidejambo said:

 

Suckered again ML

 

 

I posted that as a piss take and posted it as so.:troll:

 

Of course its fake news and was someone on the wind up :lol:

 

Good on Ully to suss it. :lol:

 

 

And show me were ONCE  i have been suckered  on this thread  never mind AGAIN..:laugh:

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On 10/02/2018 at 20:41, maroonlegions said:

:laugh:

27657436_2058359221101609_2576708517875282081_n[1].jpg

 

Please stop posting fake information, no matter how humorous it may be.

 

https://www.snopes.com/elon-musk-donald-trump-dumbass/

 

Can you not see that if you do this then you become part of the problem? On a thread that is looking at science and truth, no less.

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  • 2 weeks later...
maroonlegions

Short talk by my wifes cousin   on NASAs Mars rover Curiosity. She is an astrophysicist currently in SA working in the field of "radio galaxies". 

 

 

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On 10/02/2018 at 11:05, alfajambo said:

Your argument against the existence of a transcendent Creator God, goes something like this.

There is no God, There is no God etc.…

Can I also remind you that people believe in God because of the evidence, because of the scientific understanding we have, and because of what we see in the universe.

I remain an optimist. I believe that absolute truth is a reality and that God and the Holy Spirit can bring enlightenment to even the darkest of minds. So there is still hope for us both.

The burden of proof is on those with the unlikely beliefs. "There is no God" is a reasonable statement as there's exactly zero evidence, while your stance requires blind faith.

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18 minutes ago, Smithee said:

The burden of proof is on those with the unlikely beliefs. "There is no God" is a reasonable statement as there's exactly zero evidence, while your stance requires blind faith.

There's no big bang, multiverse infinity, worm holes, etc... There's zero evidence other than theory from humans. The same humans who documented the Bible. Blind faith.

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10 minutes ago, ri Alban said:

There's no big bang, multiverse infinity, worm holes, etc... There's zero evidence other than theory from humans. The same humans who documented the Bible. Blind faith.

Yeah, and I don't have much interest in the subject as a result, but god is still an ridiculously unlikely explanation 

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7 minutes ago, Smithee said:

Yeah, and I don't have much interest in the subject as a result, but god is still an ridiculously unlikely explanation 

God is God

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9 minutes ago, ri Alban said:

:rofl: evidence? It's all conjecture and whatifary.

 

Considerably better evidence than we have for the existence of any gods.

 

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8 minutes ago, maroonlegions said:

A gentle reminder when struggling  to survive in the rat race.

 

 

 

28378732_2035661533112062_8249046542645673250_n[1].jpg

And that big yellow thing is God.

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maroonlegions
10 minutes ago, ri Alban said:

And that big yellow thing is God.

Scientifically its a sun, billions in our own galaxy  alone.

 

Bit of a mind feck for all those "flat earthers" though. :laugh:

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1 minute ago, maroonlegions said:

Scientifically its a sun, billions in our own galaxy  alone.

 

Bit of a mind feck for all those "flat earthers" though. :laugh:

It's a star and It's more than likely the object that inspired a sense of god. 

I find it laughable the contempt you hold for religious people. Take human evolution and Adam and Eve. Who were the first humans, there must have been an original. But you laugh at the bible for having the audacity to suggest such a thing. And to me some human evolution is just a change in diet and the way we hunt and prepared food, leading to muscle enhancement and brain function. 

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1 hour ago, Maple Leaf said:

There's a very short video in the attached link that is worth watching.  It's only 2:33 minutes long.

 

It demonstrates just how small our sun is compared to some other known stars.

 

http://www.iflscience.com/space/comparing-sizes-sun-earth-and-stars/

I've seen that video a few times. Every time I see it, it still leaves me as gob smacked as the first time I seen it.

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maroonlegions

Here is another wee talk given by my wife's  cousin. Dr Imogene Whittam.

 

She gives  a brief description of "pulsars" and then goes on about the current construction of the soon to be  worlds largest land based telescope in South Africa. She is involved in this telescope and is based in SA. she is kindly keeping me up to date too.

 

 

 

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The Future's Maroon
On 25/02/2018 at 17:46, Maple Leaf said:

There's a very short video in the attached link that is worth watching.  It's only 2:33 minutes long.

 

It demonstrates just how small our sun is compared to some other known stars.

 

http://www.iflscience.com/space/comparing-sizes-sun-earth-and-stars/

 

Simply mind boggling ?

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On 2/5/2018 at 22:38, Maple Leaf said:

Carl Sagan's Cosmos, which was also a TV series, is outstanding.  One of the best books I've ever read.

 

As mentioned above, Neil deGrasse Tyson is excellent.  I'm currently reading his "Astrophysics for People in a Hurry", which I recommend.

 

Lawrence Krauss is possibly the best theoretical physicist alive.  He has a book called "The Greatest Story Ever Told ... So Far", which I also recommend, but I found it to be a bit of a slog.

 

Those, plus Ray Gin's recommendations, should keep you going for a while.  :thumbsup:

 

I started reading this yesterday and I'm half way through it already.

 

He tells it in a way that even I can understand, actually understand is probably the wrong word as it's pretty mind blowing stuff.

 

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John Gentleman
8 hours ago, graygo said:

 

I started reading this yesterday and I'm half way through it already.

 

He tells it in a way that even I can understand, actually understand is probably the wrong word as it's pretty mind blowing stuff.

 

Easy to understand but mind-bogglingly difficult to comprehend.

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  • 2 years later...

Heads up guys.

Tomorrow evening, hopefully weather is favourable. We could witness the Christmas star. Saturn and Jupiter will appear to merge in the sky.

 

 

https://www-express-co-uk.cdn.ampproject.org/v/s/www.express.co.uk/news/science/1374500/christmas-star-2020-what-time-is-great-conjunction-jupiter-saturn-december-21-evg/amp?amp_js_v=0.1&usqp=mq331AQHKAFQArABIA%3D%3D&jwsource=cl

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On 25/02/2018 at 17:46, Maple Leaf said:

There's a very short video in the attached link that is worth watching.  It's only 2:33 minutes long.

 

It demonstrates just how small our sun is compared to some other known stars.

 

http://www.iflscience.com/space/comparing-sizes-sun-earth-and-stars/

 

1:23 into that video shows VY Canis Majoris. Shouldn't it be renamed VY Liam Boyce? 

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4 hours ago, Boof said:

 

1:23 into that video shows VY Canis Majoris. Shouldn't it be renamed VY Liam Boyce? 

 

Coulda done with the big dog on for the penalties :(

 

However...anyone seen this?

 

https://htwins.net/scale2/  Superb (IMO) scale of the universe interactive slideshow.

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I have often wondered how big a star can actually be. Is there a physical limit? These thoughts began as a child when I first read of the big bang theory and how for the first 380,000 years or so there was nothing much but energy in the universe as it expanded. It was too hot for atoms to form during this period.

 

It took 380,000 years for the first atoms to form though there were smaller more elementary particles in existence prior to that.
 

Quote

In the first moments after the Big Bang, the universe was extremely hot and dense. As the universe cooled, conditions became just right to give rise to the building blocks of matter – the quarks and electrons of which we are all made.

A few millionths of a second later, quarks aggregated to produce protons and neutrons. Within minutes, these protons and neutrons combined into nuclei. As the universe continued to expand and cool, things began to happen more slowly.

It took 380,000 years for electrons to be trapped in orbits around nuclei, forming the first atoms. These were mainly helium and hydrogen, which are still by far the most abundant elements in the universe.

Present observations suggest that the first stars formed from clouds of gas around 150–200 million years after the Big Bang.

Heavier atoms such as carbon, oxygen and iron, have since been continuously produced in the hearts of stars and catapulted throughout the universe in spectacular stellar explosions called supernovae.

 

So with that in mind we can conclude that the earliest stars were formed almost entirely of hydrogen with a little helium in the mix. It occurred to me that the universe at this time was much smaller than it is now and with a lot more free hydrogen for the first stars to gather in this smaller space.

Would that mean they were large beyond imagination? A star as big as the entire solar system? I have read speculation that it's thought there is a limit. That a star can be no bigger than around 150 times the mass of the sun but this is speculation and not settled fact.

And this is only what we can see. There are far deeper mysteries still to be solved.
 

Quote

Stars and galaxies do not tell the whole story. Astronomical and physical calculations suggest that the visible universe is only a tiny amount (4%) of what the universe is actually made of.

A very large fraction of the universe, in fact 26%, is made of an unknown type of matter called "dark matter".

Unlike stars and galaxies, dark matter does not emit any light or electromagnetic radiation of any kind, so that we can detect it only through its gravitational effects. 


An even more mysterious form of energy called “dark energy” accounts for about 70% of the mass-energy content of the universe.

Even less is known about it than dark matter. This idea stems from the observation that all galaxies seems to be receding from each other at an accelerating pace, implying that some invisible extra energy is at work.

 

Mind boggling stuff.

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John Gentleman
4 hours ago, JFK-1 said:

I have often wondered how big a star can actually be. Is there a physical limit? These thoughts began as a child when I first read of the big bang theory and how for the first 380,000 years or so there was nothing much but energy in the universe as it expanded. It was too hot for atoms to form during this period.

 

It took 380,000 years for the first atoms to form though there were smaller more elementary particles in existence prior to that.
 

 

So with that in mind we can conclude that the earliest stars were formed almost entirely of hydrogen with a little helium in the mix. It occurred to me that the universe at this time was much smaller than it is now and with a lot more free hydrogen for the first stars to gather in this smaller space.

Would that mean they were large beyond imagination? A star as big as the entire solar system? I have read speculation that it's thought there is a limit. That a star can be no bigger than around 150 times the mass of the sun but this is speculation and not settled fact.

And this is only what we can see. There are far deeper mysteries still to be solved.
 

 

Mind boggling stuff.

In today's universe, with its relative abundance of heavy elements, a max mass of 150 solar masses sounds about right. In the young universe (~13 billion l/years) it's theorised that they could get to 300 solar masses due to the absence of heavy elements, ie, they were all hydrogen with a little bit of helium. That generation of stars (Population III) burned fast and died young, often lasting lasting no more than a few million light years. That makes detection and observation almost impossible. This could all change with the launch and deployment of the James Webb telescope in Oct 21. It's huge mirror and infrared sensors can probe the deep, deep past -- all the way back to the reionisation event. Hopefully, we can catch a few of those monsters in the act. It'll tell us a lot about who we are and where we are today.

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5 hours ago, John Gentleman said:

In today's universe, with its relative abundance of heavy elements, a max mass of 150 solar masses sounds about right. In the young universe (~13 billion l/years) it's theorised that they could get to 300 solar masses due to the absence of heavy elements, ie, they were all hydrogen with a little bit of helium. That generation of stars (Population III) burned fast and died young, often lasting lasting no more than a few million light years. That makes detection and observation almost impossible. This could all change with the launch and deployment of the James Webb telescope in Oct 21. It's huge mirror and infrared sensors can probe the deep, deep past -- all the way back to the reionisation event. Hopefully, we can catch a few of those monsters in the act. It'll tell us a lot about who we are and where we are today.

 

I'm excited about the prospect of what the James Webb telescope may find. I suspect the dazzling disoveries of the Hubble space telescope may be eclipsed.

 

For those who haven't researched it the James Webb telescope will be deployed at what's called a Lagrange point almost a million miles out from the Earth which is over 3 times the distance from Earth to the moon. It will be in the shadow of the Earth effectively blocking out light pollution from the Sun.

 

One concern I have is that if there were a problem with the telescope there can be no mission to resolve it. Not at that distance. When Hubble was first deployed there was a lens issue which rendered it useless. All images were an out of focus blur.

 

In that instance a shuttle mission was launched and astronauts had to carry out a spacewalk to apply a corrective lens patch. Luckily that worked perfectly and Hubble ultimately returned some historic and stunning images. Not possible at the distance the James Webb will be if it had a problem.

 

Quote

The JWST will be located near the second Lagrange point (L2) of the Earth-Sun system, which is 1,500,000 kilometres (930,000 mi) from Earth, directly opposite to the Sun.

 

Normally an object circling the Sun farther out than Earth would take longer than one year to complete its orbit, but near the L2 point the combined gravitational pull of the Earth and the Sun allow a spacecraft to orbit the Sun in the same time it takes the Earth.

 

The telescope will circle about the L2 point in a halo orbit, which will be inclined with respect to the ecliptic, have a radius of approximately 800,000 kilometres (500,000 mi), and take about half a year to complete.

 

Since L2 is just an equilibrium point with no gravitational pull, a halo orbit is not an orbit in the usual sense: the spacecraft is actually in orbit around the Sun, and the halo orbit can be thought of as controlled drifting to remain in the vicinity of the L2 point.

 

This requires some station-keeping: around 2–4 m/s per year from the total budget of 150 m/s. Two sets of thrusters constitute the observatory's propulsion system.

 

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John Gentleman
1 hour ago, JFK-1 said:

 

I'm excited about the prospect of what the James Webb telescope may find. I suspect the dazzling disoveries of the Hubble space telescope may be eclipsed.

 

For those who haven't researched it the James Webb telescope will be deployed at what's called a Lagrange point almost a million miles out from the Earth which is over 3 times the distance from Earth to the moon. It will be in the shadow of the Earth effectively blocking out light pollution from the Sun.

 

One concern I have is that if there were a problem with the telescope there can be no mission to resolve it. Not at that distance. When Hubble was first deployed there was a lens issue which rendered it useless. All images were an out of focus blur.

 

In that instance a shuttle mission was launched and astronauts had to carry out a spacewalk to apply a corrective lens patch. Luckily that worked perfectly and Hubble ultimately returned some historic and stunning images. Not possible at the distance the James Webb will be if it had a problem.

 

 

They seem to have gone to a lot of trouble to avoid 'Hubbling it'. So, short of a launch rocket failure, fingers crossed...

https://www.jwst.nasa.gov/content/about/faqs/faq.html#mirrortests

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19 hours ago, Boof said:

Similar but different.

 

 

 

Absolutely brilliant vid Boof, thanks.

 

bUt ThErE's No EvIdEnCe :rolleyes:

 

 

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19 hours ago, Boof said:

Similar but different.

 

 

 

Staggering! 

 

The music is from the original Carl Sagan series "Cosmos", by Vangelis, I believe.

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8 minutes ago, Maple Leaf said:

The music is from the original Carl Sagan series "Cosmos", by Vangelis, I believe.

 

Definitely Vangelis - not sure of the rest.

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hey guys, stop derailing my bumped thread.

 

looks like weather is scuppering me from seeing jupiter and saturn merging in the sky tonight.

 

how's the sky in Shetland, @Boof

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3 minutes ago, Tommy Brown said:

hey guys, stop derailing my bumped thread.

 

looks like weather is scuppering me from seeing jupiter and saturn merging in the sky tonight.

 

how's the sky in Shetland, @Boof

 

Dunno - it's too dark to see it...

 

Nah, not been out for a wee while and sitting in a windowless room just now but about 2pm it was looking like being too cloudy for a decent view.

 

Hopefully it'll have cleared a bit. My Mrs will be trying to get photos so she'll keep me updated.

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15 minutes ago, Greedy Jambo said:

The sky is always bloody cloudy when something is meant to happen lol. 

 

If it's any compensation, much-hyped astronomical events are usually anticlimactic.

 

Jupiter is normally not very bright, and Saturn is quite faint.  Even putting them together, it is unlikely to be as bright as Venus on a normal night ... imo.

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22 minutes ago, Maple Leaf said:

 

If it's any compensation, much-hyped astronomical events are usually anticlimactic.

 

Jupiter is normally not very bright, and Saturn is quite faint.  Even putting them together, it is unlikely to be as bright as Venus on a normal night ... imo.

 

Jupiter has been quite bright here over the last year, it doesn't look like I'll be seeing a thing tonight though. 

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Here's a question for brighter minds than mine, which is most! 

 

One often hears comments like "x million years after the Big Bang."  As we all know, a year to us earthlings is the length of time it takes for our planet to do a complete orbit of the sun.  But the sun and earth weren't formed until about 6 billion years after the Big Bang, so what was a "year" prior to that? 

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11 minutes ago, Maple Leaf said:

Here's a question for brighter minds than mine, which is most! 

 

One often hears comments like "x million years after the Big Bang."  As we all know, a year to us earthlings is the length of time it takes for our planet to do a complete orbit of the sun.  But the sun and earth weren't formed until about 6 billion years after the Big Bang, so what was a "year" prior to that? 

 

I'll no doubt get shot down for this, but the big bang just sounds like a cop out to me, like they don't really know what happened so they just came up with a mad explosion that created everything. 

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