Physics and astronomy thread (2 Viewers)

[Galileo]

I was going to use the "shopped" gag... because it honestly looks shopped. 

but what aspect of the perspective do you have an issue with? that we could see Saturn from Earth lined up with the moon? 

reading the comments- the people who come across as most reasonable are the ones defending it as probably real.  no idea.

It is "shopped".  It is not fake, but it has been enhanced  for color and brightness through the use of editing tools.  Here is the description from the guy who created it...

Jan Koet

3 years ago

It is quite some time ago I did this, but I remember that I split the AVI into separate frames with the French astronomical freeware software IRIS, (though I found out later this can be done a lot easier with more common software). Then I loaded every single frame into Photoshop. With the magic selection tool I selected Saturn with a feather of a few pixels by trial and error. Then Saturn was brightened with levels and curves and some tweaking with color and a little noise reduction. I remember me using 17 small steps for each frame, about 3000 in total using an action. After that I used the video editor of the ancient Paint Shop Pro 6 to make the movie. To make the movie to play a bit ‘smooth’ I loaded this AVI in Registax 3 to make the final AVI, by application of a running average of 3 frames. The duration of the original AVI is longer then displayed but I never published it.

 

[Andy Dufresne]

I was going to use the "shopped" gag... because it honestly looks shopped. 

but what aspect of the perspective do you have an issue with? that we could see Saturn from Earth lined up with the moon? 

reading the comments- the people who come across as most reasonable are the ones defending it as probably real.  no idea.

I'm not even a novice, and it's hard to explain what I mean, but I don't get how it would look so big while seeing so much of the moon's horizon.

And it seems like it's an image that would have already been captured if possible.

Edit: @Galileo...so Saturn could appear that big? The image has just been "enhanced"?

 

[Andy Dufresne]

More images from Webb...

It's already producing some amazing stuff and it's not even fully operational.

 

[FBG26]

Beginning of the end for Ingenuity?

 

[Galileo]

I'm not even a novice, and it's hard to explain what I mean, but I don't get how it would look so big while seeing so much of the moon's horizon.

And it seems like it's an image that would have already been captured if possible.

Edit: @Galileo...so Saturn could appear that big? The image has just been "enhanced"?

Saturn is pretty damn big.  As a knee jerk reaction, the size in this photo/video doesn't strike me as problematic.  I haven't done any calculations to verify that though.

 

[Runkle]

I'm not even a novice, and it's hard to explain what I mean, but I don't get how it would look so big while seeing so much of the moon's horizon.

And it seems like it's an image that would have already been captured if possible.

Edit: @Galileo...so Saturn could appear that big? The image has just been "enhanced"?

I've seen Saturn through just a telescope on a tripod and it looked kinda like that. It's pretty neat to see. 

 

[Galileo]

Saturn is pretty damn big.  As a knee jerk reaction, the size in this photo/video doesn't strike me as problematic.  I haven't done any calculations to verify that though.

OK, from a quick number crunch using the reported diameters and distances to the moon and Saturn from Wiki, I would expect the moon to appear anywhere from about 90-240 times bigger across than Saturn in the sky.  In this image, the Earth and Saturn are on the same "side" of the sun and thus at a time when they are relatively close together and it would appear larger.  Thus we should be towards the lower end of the range I reported.  So, the moon appears roughly 100x larger across. This is for the disk of Saturn.  I did not include the rings.  The image seems reasonable.  

 

[El Floppo]

Beginning of the end for Ingenuity?

nooooooooooo

 

[Andy Dufresne]

I've seen Saturn through just a telescope on a tripod and it looked kinda like that. It's pretty neat to see. 

OK, from a quick number crunch using the reported diameters and distances to the moon and Saturn from Wiki, I would expect the moon to appear anywhere from about 90-240 times bigger across than Saturn in the sky.  In this image, the Earth and Saturn are on the same "side" of the sun and thus at a time when they are relatively close together and it would appear larger.  Thus we should be towards the lower end of the range I reported.  So, the moon appears roughly 100x larger across. This is for the disk of Saturn.  I did not include the rings.  The image seems reasonable.  

Well then that is really cool!

 

[El Floppo]

I've seen Saturn through just a telescope on a tripod and it looked kinda like that. It's pretty neat to see. 

OK, from a quick number crunch using the reported diameters and distances to the moon and Saturn from Wiki, I would expect the moon to appear anywhere from about 90-240 times bigger across than Saturn in the sky.  In this image, the Earth and Saturn are on the same "side" of the sun and thus at a time when they are relatively close together and it would appear larger.  Thus we should be towards the lower end of the range I reported.  So, the moon appears roughly 100x larger across. This is for the disk of Saturn.  I did not include the rings.  The image seems reasonable.  

Well then that is really cool!

wiht all this info now- pretty amazing to set that shot up... they had to dial into the exact spot on the moon where they knew Saturn would be "rising" and zoom in as much as possible while keeping a part of the moon in frame for context. hearing about the photo manipulation to make clarity/light/etc adjustments frame by frame... even more amazing.

 

[joffer]

OK, from a quick number crunch using the reported diameters and distances to the moon and Saturn from Wiki, I would expect the moon to appear anywhere from about 90-240 times bigger across than Saturn in the sky.  In this image, the Earth and Saturn are on the same "side" of the sun and thus at a time when they are relatively close together and it would appear larger.  Thus we should be towards the lower end of the range I reported.  So, the moon appears roughly 100x larger across. This is for the disk of Saturn.  I did not include the rings.  The image seems reasonable.  

agree.  it’s possible just from size/distance perspective.  quite a view.

 

[Andy Dufresne]

Good news!

We can now see our own (black) hole!

 

[Galileo]

The European Southern Observatory is planning a global press conference to announce "groundbreaking Milky Way results" on May 12th.  The results are coming from the Event Horizon Telescope project which brought us the first images of a black hole (center of the M87 galaxy) a couple years ago.  Perhaps they have imaged Sagittarius A at the center of the Milky Way???

 https://eventhorizontelescope.org/blog/event-horizon-telescope-collaboration-announce-groundbreaking-milky-way-results-may-12th

Good news!

We can now see our own (black) hole!

I was busy today and forgot about the press conference, but as I expected…

 

[Galileo]

Here is an informative video from Veritasium about the challenges and techniques used for capturing an image of a black hole like M87 and Sagittarius A.  They also do a great job of explaining what it is we are actually seeing in these images as well.

 

[Hastur]

I was busy today and forgot about the press conference, but as I expected…

Holy smokes!

The project took five years to complete, including 100 million hours of supercomputer time at the US' National Science Foundation.

 

[Sand]

Holy smokes!

The project took five years to complete, including 100 million hours of supercomputer time at the US' National Science Foundation.

Is this supercomputer dilating time?

 

[Hastur]

Is this supercomputer dilating time?

I did some quick excel math and it comes out to 11,000 years and change.  How the....?

 

[Runkle]

I did some quick excel math and it comes out to 11,000 years and change.  How the....?

Hint: when a project has "10,000 man hours", that doesn't mean one man working 10,000 hours by himself

 

[Galileo]

I did some quick excel math and it comes out to 11,000 years and change.  How the....?

The author of the article linked by Andy up thread says "100 million hours of supercomputing time".  I think this is a bit of misinterpretation.  The National Science Foundation cites that analysis "includes nearly 80 million CPU hours on the NSF Frontera supercomputer and 20 million CPU hours on the NSF Open Science Grid."  However, a "CPU hour" is not a direct measure of time.  Rather in this context, it is a measure of the amount of work/computations done.   This link explains the CPU hour a little.

 

[Sand]

The author of the article linked by Andy up thread says "100 million hours of supercomputing time".  I think this is a bit of misinterpretation.  The National Science Foundation cites that analysis "includes nearly 80 million CPU hours on the NSF Frontera supercomputer and 20 million CPU hours on the NSF Open Science Grid."  However, a "CPU hour" is not a direct measure of time.  Rather in this context, it is a measure of the amount of work/computations done.   This link explains the CPU hour a little.

You're ruining my time dilation argument.  Begone, you.

 

[El Floppo]

Hint: when a project has "10,000 man hours", that doesn't mean one man working 10,000 hours by himself

A million men taking 15 seconds?

Eta...

-floppowife's sex life.

 

[Van Dyman]

A million men taking 15 seconds?

Eta...

-floppowife's sex life.

Glad I could contribute.

 

[El Floppo]

Glad I could contribute.

Million man march.

Take my wife, please.

 

[The Gator]

May 31st Could Be the Most Powerful Meteor Storm in Generations, or Nothing at All

 

[Sand]

Dateline May, 2022 - V'Ger is born.

It's not like we weren't warned.

 

[Maggot Brain]

These Telescopes Will Change the Way We See Space

Very good stuff here.

 

[STEADYMOBBIN 22]

These Telescopes Will Change the Way We See Space

Very good stuff here.

I guess when youre busy naming stars you lose your inspiration when naming telescopes. 

Actual names of some of these telescopes:

Extremely Large Telescope (replaces the Very Large Telescope)

Thirty Meter Telescope

Giant Magellan Telescope

The Legacy Survey of Space and Time (formerly Large Synoptic Survey Telescope)

 

[GregR]

Ok, so long as the math checks out

 

[Andy Dufresne]

Ok, so long as the math checks out

Abbot and Costello: 13 x 7 = 28

 

[Van Dyman]

Abbot and Costello: 13 x 7 = 28

Pretty good. I hadn't seen that.

 

[2Squirrels1Nut]

Humans could become a truly interplanetary species within 200 years, physicists claim

 

[Sand]

Scientists have now explained why Neptune and Uranus are different colors, despite very similar makeups:  Smog on Uranus

 

[Galileo]

Scientists have now explained why Neptune and Uranus are different colors, despite very similar makeups:  Smog on Uranus

poor hygiene?

 

[heckmanm]

Scientists have now explained why Neptune and Uranus are different colors, despite very similar makeups:  Smog on Uranus

Obscure Deep Purple album track

 

[dkp993]

poor hygiene?

Poor hygiene on Uranus is never a good thing.  

 

[Andy Dufresne]

The universe is flat.

Meaning...what? It's not spherical? Should be thought of like a sheet of paper?

I get it, yet I don't.

 

[The Gator]

May 31st Could Be the Most Powerful Meteor Storm in Generations, or Nothing at All

Anyone here check this out? 
 

The wife and I were out abs it was meh from our area. We saw some shooting stars, but not what we’re hoping for. 
 

 

[Galileo]

The universe is flat.

Meaning...what? It's not spherical? Should be thought of like a sheet of paper?

I get it, yet I don't.

It is not curved.  Curved could be spherical, but a sphere is not a requirement of curvature.  Space is flat, but spacetime is curved.  Chew on that!

 

[Andy Dufresne]

It is not curved.  Curved could be spherical, but a sphere is not a requirement of curvature.  Space is flat, but spacetime is curved.  Chew on that!

But can it be spherical without being curved?

Tango, Cash...Cash, Tango!!

 

[Galileo]

But can it be spherical without being curved?

Tango, Cash...Cash, Tango!!

No.  All spheres have curvature.  Not all things curved are spheres

 

[Andy Dufresne]

No.  All spheres have curvature.  Not all things curved are spheres

So then the universe isn't a sphere. So what is it? The closest approximation...

I suppose the safest answer is "infinite".

 

[joffer]

Krauss had a cool YouTube video like 10 years ago on the whole open/flat/closed universe thing.  I thought he explained it pretty well.

 

[Galileo]

So then the universe isn't a sphere. So what is it? The closest approximation...

On a cosmological scale, evidence suggests it is flat.  This is described in the article you posted which claims flatness to within 99.6% precision and thus if there is any curvature, it happens over a scale larger than the observable universe.

 

[Andy Dufresne]

On a cosmological scale, evidence suggests it is flat.  This is described in the article you posted which claims flatness to within 99.6% precision and thus if there is any curvature, it happens over a scale larger than the observable universe.

Flat as in if you looked at it from the side it would appear as a line? Or is it the more out there idea that no matter where you look at it, it's flat?

Let me ask a different way...If you're inside the universe, no matter where you observe it it would look flat - as in you can't discern any curvature.

But what if you looked at it from the outside? Does it look two dimensional? Three? What object does it look like? A line? A box?

This isn't far from the thought experiment that is Flatland.

 

[Galileo]

Flat as in if you looked at it from the side it would appear as a line? Or is it the more out there idea that no matter where you look at it, it's flat?

Let me ask a different way...If you're inside the universe, no matter where you observe it it would look flat - as in you can't discern any curvature.

But what if you looked at it from the outside? Does it look two dimensional? Three? What object does it look like? A line? A box?

This isn't far from the thought experiment that is Flatland.

The bolded is your best way to think of it.  It really is not a meaningful question to ask what it would look like from the outside.

I have heard it put this way before...Imagine you and 2 friends get into three different space ships and travel to ANY 3 distinct locations anywhere in the universe.  You then each shine a laser to the other two spaceships.  You then measure the angles formed by the interior angles.  If they total 180 degrees...flat.  If they total greater than or less than 180 deg...curved.  For an earthly analogy, imagine walking due north from the equator to the north pole, turn left and then walk due south back to the equator.  Finally return along the equator to your starting position.  You will have traveled in a triangle that was mapped upon a curved surface and the interior angles would sum to a value larger than 180.  

 

[Andy Dufresne]

I think I get it.

We're not saying that the "container" is flat.

We're saying that everywhere "inside" is flat.

 

[Runkle]

I think I get it.

We're not saying that the "container" is flat.

We're saying that everywhere "inside" is flat.

Yeah, I think the "flat" meaning is that, in our universe, no matter how infinitely long they travel, two parallel lines will always be parallel, and never converge nor move farther apart. Every 2D 'slice' of our 3D existence is flat forever. They're not saying that our universe is actually 2D. 

 

[El Floppo]

I think I get it.

We're not saying that the "container" is flat.

We're saying that everywhere "inside" is flat.

Yeah, I think the "flat" meaning is that, in our universe, no matter how infinitely long they travel, two parallel lines will always be parallel, and never converge nor move farther apart. Every 2D 'slice' of our 3D existence is flat forever. They're not saying that our universe is actually 2D. 

I call our world Flatland, not because we call it so, but to make its nature clearer to you, my happy readers, who are privileged to live in Space.

 

[STEADYMOBBIN 22]

Yeah, I think the "flat" meaning is that, in our universe, no matter how infinitely long they travel, two parallel lines will always be parallel, and never converge nor move farther apart. Every 2D 'slice' of our 3D existence is flat forever. They're not saying that our universe is actually 2D. 

This is the best explanation I’ve ever read.

 

[Runkle]

This is the best explanation I’ve ever read.

I think, if the universe was "curved", it means that it would be possible to go out in one direction straight away, and it would feasibly be possible that you could then come up on your original position from behind. Which sounds a little weird, but, that's how it is on the surface of the Earth... it looks flat but if you walked in one direction for 24000 miles you'd come back to where you started from. A "flat" universe means that it's just forever infinite in that line.