The universe - big innit

[yoda559]

this is worth a look at

The Scale of the Universe 2

makes you realise how small we really are!

 

[DumLum]

The Universe is indeed large but the Amex is slowly catching up.

 

[perseus]

What planet are you on ?

☿ ♀ ♁ ♂ ♃ ♄ ♅ ♆

☄ just testing

 

[m20gull]

the thing is, that's just the observable universe too! They think now (nearly all leading physicists) that there are multiple of universes, maybe even an infinite amount of them constantly springing into existence on a regular basis.

The key word there is "think", I believe. A multiverse model works but I cannot see how you necessarily conclude that multiple universes exist.

 

[glasfryn]

Never have thought we were alone... Just do not believe it's little green men... Just because there isn't life on our solar system (not even that can be confirmed) does not mean we are alone... The universe has billions of galaxies and our whole galaxy has billions of solar systems.

I like this you tube clip... Awesome...

this
video is a bit like Milton Keynes on a wet Sunday afternoon

there is life out there somewhere

 

[Meade's Ball]

I'm waiting for the day when we reach the edge of the universe, topple into Hell itself, veering our way through the horrific acts and thoughts and tortures and Spielberg horse dramas we're meant to view and absorb, and reappear on the other side to be found by a wreckage crew, still with the truest element of evil lurking in the ship's nucleus. Then, we'll make everyone eat their own hands. Liberate tuteme ex inferis.

 

[GYM]

42!

 

[dingodan]

 

[dingodan]

 

[glasfryn]

42!

inter galactic highways lets protest

 

[dingodan]

 

[Igzilla]

Exactly my point, and the article is telling you that we are at the very beginning of understanding exoplanets. Our only knowledge of them is not from themselves directly, but of their impact on the star that they orbit, we measure the effect the exoplanet has on the information we can measure from the star. In that respect, what we know is through theoretical conjecture, and not through being able to see and measure the exoplanet itself. I think one or 2 people take things far too literally. I would have thought the statement 'concrete' evidence, i.e. we can see the moon and land on it, does not apply to exoplanets orbiting other stars.

Hi there, my first post on NSC, but this I just couldn't resist, as I studied this particular subject for my 4th Year Uni project. Bold Seagull is correct in the sense that you can only infer the prescence of planets due to their effect on the star's Doppler shift (Radial Velocity method) or the star's brightness (Transit or Gravitational Microlensing Methods). However, this is not really any different from infering the existance of electrons. After all, we can't see them or take a picture of an electron (or proton, neutron, neutrino or any other sub-atomic particle), but we know they exist as we have electricity, for example. Does this mean Bold Seagull does not believe in electricity? Probably not.

Also, there has been direct imaging of an exoplanet (around the star Fomalhaut in it's circumstellar disk) - not sure sure how to post images yet, so here's a link:

http://www.nasa.gov/mission_pages/hubble/science/fomalhaut_feature.html

Also this: Page F30: This year's most exciting astronomical photo - HR 8799

Compare to Pluto (best image from HST): Astronomy: Pluto and Kuiper Belt

Not bad, considering just how far away these things are. Remember, seeing is NOT believing - just google for optical illusions and you'll appreciate that the human eye is not to be trusted. That's why all the confirmed exoplanets to date have been verified by different groups using different methods - triangulation, if you like to ensure that what is being measured could ONLY be caused by a body in orbit around the target star. Life, on the other hand, is a different matter and a different discussion.

 

[Bold Seagull]

Hi there, my first post on NSC, but this I just couldn't resist, as I studied this particular subject for my 4th Year Uni project. Bold Seagull is correct in the sense that you can only infer the prescence of planets due to their effect on the star's Doppler shift (Radial Velocity method) or the star's brightness (Transit or Gravitational Microlensing Methods). However, this is not really any different from infering the existance of electrons. After all, we can't see them or take a picture of an electron (or proton, neutron, neutrino or any other sub-atomic particle), but we know they exist as we have electricity, for example. Does this mean Bold Seagull does not believe in electricity? Probably not.

Also, there has been direct imaging of an exoplanet (around the star Fomalhaut in it's circumstellar disk) - not sure sure how to post images yet, so here's a link:

http://www.nasa.gov/mission_pages/hubble/science/fomalhaut_feature.html

Also this: Page F30: This year's most exciting astronomical photo - HR 8799

Compare to Pluto (best image from HST): Astronomy: Pluto and Kuiper Belt

Not bad, considering just how far away these things are. Remember, seeing is NOT believing - just google for optical illusions and you'll appreciate that the human eye is not to be trusted. That's why all the confirmed exoplanets to date have been verified by different groups using different methods - triangulation, if you like to ensure that what is being measured could ONLY be caused by a body in orbit around the target star. Life, on the other hand, is a different matter and a different discussion.

Good first post!

I wasn't for a second suggesting or refuting the existence of exoplanets, merely as you say pointing out that their evidence is inferred, and despite being able to triangulate methods, it is still difficult to be absolutely sure about composition and size of these planets. What will be interesting in coming years is how our understanding of quantum mechanics changes some of the fundamental principles we've applied to physics.......which is where my already basic knowledge starts to look shakier than a Tory chief whip getting out of Downing Street on a push bike.

 

[Bold Seagull]

Wow, some more incredibly high resolution images of crop circles.

 

[Igzilla]

Good first post!

I wasn't for a second suggesting or refuting the existence of exoplanets, merely as you say pointing out that their evidence is inferred, and despite being able to triangulate methods, it is still difficult to be absolutely sure about composition and size of these planets. What will be interesting in coming years is how our understanding of quantum mechanics changes some of the fundamental principles we've applied to physics.......which is where my already basic knowledge starts to look shakier than a Tory chief whip getting out of Downing Street on a push bike.

Thanks, Bold Seagull. Point taken - certainly the Radial Velocity method can only give a lower mass for the planet, as it depends upon the angle of inclination of the plane of the orbit perpendicular to the viewer (mass x sine of angle). The Transit method does give a good indication of diameter, though, as the dip in brightness can be measured, and it is an easy calculation to determine how large a disc can cause the dip. Knowing the mass of the star (based on colour, temperature and other spectroscopic measurements), we know its diameter, so by measuring how long the dip lasts for, you can work out how far the planet is from the star, based on follow up Doppler measurements (as you know that the sine of the angle is 1 becuase otherwise you wouldn't see a transit), you know its mass, so therefore it's density. Added to that, when the planet goes behind the star, you can subtract the two readings and what's left is the signature of the planet alone. This allows you to determine what the atmosphere is composed of and how hot it is. You can even tell if there are cloud formations. Also, by measuring the variations in how long it takes to transit, you can infer further planets that may not necessarily transit or have much longer orbital periods.

 

[TWOCHOICEStom]

Anyone thinking that there's not another planet like ours in the trillions of other galaxies containing trillions of other stars orbited by trillions of other planets is a little bit narrow minded in my opinion.

 

[The Kid Frankie]

If there is an infinite number of stars and therefore planets. Then I\'d go as far to say that the likelihood of there being civilizations capable of inter-steller travel would be night on certain. The one big drawback is the universe is so fecking big the chances of them noticing us are remote. That being said, we are constantly sending out radio waves advertising our presence (against the wishes of Steven Hawkings I might add - he\'s clearly watched Independence Day one too many times).

 

[sten_super]

If there is an infinite number of stars and therefore planets. Then I\'d go as far to say that the likelihood of there being civilizations capable of inter-steller travel would be night on certain. The one big drawback is the universe is so fecking big the chances of them noticing us are remote. That being said, we are constantly sending out radio waves advertising our presence (against the wishes of Steven Hawkings I might add - he\'s clearly watched Independence Day one too many times).

The 'infinite' nature of the universe is a real mind-bender for me. Theoretically, in an infinite universe, there will be an infinite number of planets like earth, an infinite number of other life-based civilisations and, assuming that there is some way of travelling ridiculous distances (such as folding space or utilising alternate dimensions) an infinite number of civilisations that are able to utilise this technology. Therefore, the chance of none of these civilisations happening upon Earth or our transitions is correspondingly zero. In which case why haven't we heard from them?


*This post is sponsored by the two pints that I had instead of lunch*

 

[Bold Seagull]

If there is an infinite number of stars and therefore planets. Then I\'d go as far to say that the likelihood of there being civilizations capable of inter-steller travel would be night on certain. The one big drawback is the universe is so fecking big the chances of them noticing us are remote. That being said, we are constantly sending out radio waves advertising our presence (against the wishes of Steven Hawkings I might add - he\'s clearly watched Independence Day one too many times).

Radio waves travelling at the speed of light will take 4 years to reach the next nearest star. There are about 1000 stars within 100 light years of our sun. It would then take 2.5 million years for the same waves to reach our next nearest galaxies...

 

[Dub-67]

If the universe is infinite.. which it may be.. then everything exists.. everything that can possibly exist exists..

I've seen a few posts about 'how incredibly small we are' ... but you've also got to consider that space doesnt just 'go outwards' for unimaginally vast distances.. it also goes inwards to unimaginally small proportions.. It gets smaller and smaller and smaller.. From that perspective, we are in fact incredibly big!

The greeks came up with atoms.. we then find they are made of protons, neutrons and electrons, we then find these are made of smaller bits and pieces.. quarks.. even one called 'strangeness' and another called 'charm' (I'm not making this up) and now we know these are made of even smaller 'particles' and it goes on.

It may go 'inwards' as much as it goes' outwards' now that really is a headspinner.

Also notice I used 'particles' in apostrophes.. because as we now no most of an atom (99.99 %) is empty space.. and the other bits and their sub atomic componants are actually imnpossible to put a definate finger on anyway.. The best way to describe them is as 'clouds of probability'... So what actually really exists anyway ?? Is anything real.. or just the product of our projective imagination ?

Consiousness might itself exist outside of time and space.. this is controversial, but this 'dualistic' idea is gaining support recently in philosophical circles..

Oopppss sorry.. just realised I am rantinig like a nutter