# Ask Me AnythingAMA with Dr. Joe Pesce

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#### Ianel

Hi! Should we consider the standard model of particles as sufficient or more precisely right to explain the Universe? I mean the Universe is like a Rubik's cube. A lot of theories could possibly explain it but only one will give the exact match. The others are false positive. What if we got wrong all this time? We have a theory for not explaining most of the Universe. It's insane.

jchamot and IG2007

#### DrJoePesce

Verified Expert
Hi Dr. Joe

If photons are massless particles, why are they affected by the extreme gravity of Black Holes. If they have no mass then they should be able to escape the gravity of a Black Hole or is it the extreme curvature of Spacetime in Black Holes that trap photons and not actually gravity itself?

I like the thought process here RSchmidt! You are correct – photons have no mass. So it is the curvature of space that traps the photons. Think of that distortion of a rubber sheet by a weight, and if you roll a ball on the sheet it’s path bends as it goes by/through the deformed sheet. If the deformation is great enough, instead of merely bending, the ball will eventually circle around the weight - go into orbit in the real world - and that orbit will eventually be such that the ball falls onto the weight. The same thing is happening around the black hole with matter and photons.

Still thinking of the distortion of the rubber sheet: If something is moving away from the weight it has to climb out of the distortion of the rubber sheet, and this takes energy (the more the distortion the greater the energy required). This explains the gravitational redshift I mentioned in another, earlier, post. The photon is climbing out of the gravitational well and loses energy as it goes. A photon that loses energy has it’s wavelength increase, and an increasing wavelength means redward; hence “redshift”.

By the way, any mass distorts space-time (it’s just that the more mass the more the distortion), so there is such a distortion around our Sun that bends light. This was detected in 1919 by Arthur Eddington and colleagues in the first test of the theory of relativity.

jchamot and IG2007

#### DrJoePesce

Verified Expert
I believe I have read descriptions that space (spacetime) flows into blackholes. Is this a legit hypothesis and testable? Or is it a way to better map events around it? Or is spacetime just warped, not dissimilar than my memory of that flowing account, perhaps.

Well, black holes are within spacetime (as we all are), and they distort spacetime. I’m not sure about spacetime “flowing” into a black hole….

Of course we don’t know what’s going on inside the event horizon.

jchamot and IG2007

#### IG2007

##### "Don't criticize what you can't understand..."
@DrJoePesce , thank you for answering to my previous questions. I am about to give you a hypothetical situation, and you have to tell what is gonna happen in there. I hope that you'll find the question interesting.

Sagittarius A* is at the centre of the Milky Way. And, a proton is just about to enter the Event Horizon of the Black hole. A spaceship is standing 1 lightyear away from the proton.

We know that, relative to the spaceship, the proton will appear "frozen in time". But, the question is, is the opposite also true? Will the spaceship, relative to the proton, also appear stopped in time?

I have another question. What do you think about the Big Bang Theory? Have we got enough evidence to prove it wrong? Will we ever get any?

#### iwillgotospacein15years

What is your opinion on Space Tourism, and do you think that budgeting so that I save \$200,000 by 2035 just in case space tourism is a thing is enough money?

jchamot and IG2007

#### DrJoePesce

Verified Expert
Hi! Should we consider the standard model of particles as sufficient or more precisely right to explain the Universe? I mean the Universe is like a Rubik's cube. A lot of theories could possibly explain it but only one will give the exact match. The others are false positive. What if we got wrong all this time? We have a theory for not explaining most of the Universe. It's insane.

Thanks for the great question, that gets to the scientific method. Theories, or, more precisely, hypotheses are guesses as to the answer of how the universe works. Scientific hypotheses make predictions that can be tested (if the Sun distorts space, then starlight is bent as it passes nearby) – if they can’t be tested, it’s not science. Astronomers are constantly testing hypotheses, and new observations (or new technology that provide better observations) allow us to test the predictions, make new predictions, tweak the hypotheses, reject and/or modify the hypotheses. Over time, as more and more observations fail to reject a hypothesis, we gain more and more confidence that that initial guess is close to being correct. And then it starts to be called a theory. But it never ends: Maybe we’ve tested something for 100 years, and every test fails to falsify or reject the theory (the theory of relativity, say). So, it either means that theory is absolutely correct; or it’s more likely that we haven’t asked the right questions, made the right observations, or don’t have the technology to fully test the theory. Maybe an astronomer in 500 years finally makes an observation or devises an experiment which completely invalidates the theory of relativity. This is what science is all about – constantly testing our predictions. And, by the way, many times we don’t completely invalidate a hypothesis, but new observations or experiments allow us to refine the hypothesis. The Big Bang model is just such an example. It worked well for a while, but then observations indicated some problems with it. It was tweaked by adding “inflation” which created a better model of the universe.

We think there may be a model that combines everything under one theory (and that would be kind of neat). But it doesn’t mean the universe works that way; in fact, there are probably multiple components contributing to the whole. So, we will always have an incomplete view of the universe, and as a consequence our models, hypotheses, and theories will also be incomplete. But they (and our understanding of the universe around us) get better with time. This is the great nature of science

Helio and jchamot

#### DrJoePesce

Verified Expert
@DrJoePesce , thank you for answering to my previous questions. I am about to give you a hypothetical situation, and you have to tell what is gonna happen in there. I hope that you'll find the question interesting.

Sagittarius A* is at the centre of the Milky Way. And, a proton is just about to enter the Event Horizon of the Black hole. A spaceship is standing 1 lightyear away from the proton.

We know that, relative to the spaceship, the proton will appear "frozen in time". But, the question is, is the opposite also true? Will the spaceship, relative to the proton, also appear stopped in time?

I have another question. What do you think about the Big Bang Theory? Have we got enough evidence to prove it wrong? Will we ever get any?

Thanks! No, for the proton on the Event Horizon, everything appears normal; until it falls through the EH…. And then we don’t know what happens!

The Big Bang model seems to describe things very well (better than other models; like the steady state model, for example). That doesn’t mean it won’t be modified or rejected in the future with new observations. I can’t know, of course, what kinds of observations or questions or new technology may be available in the future. Certainly there is a possibility that another model will replace it; but for now that isn’t the case.

jchamot and IG2007

#### DrJoePesce

Verified Expert
What is your opinion on Space Tourism, and do you think that budgeting so that I save \$200,000 by 2035 just in case space tourism is a thing is enough money?

Well, I certainly can’t tell you to budget or not!

In my opinion, space tourism will happen. But space travel is HARD (and expensive), so the question is when will it happen? And all bets are off: over my lifetime, there have been promises of space tourism “within 10-20 years”; and I’m still waiting!

#### iwillgotospacein15years

Well, I certainly can’t tell you to budget or not!

In my opinion, space tourism will happen. But space travel is HARD (and expensive), so the question is when will it happen? And all bets are off: over my lifetime, there have been promises of space tourism “within 10-20 years”; and I’m still waiting!

That's very true...luckily I am only 20 so HOPEFULLY in my lifetime it will happen!

#### Helio

Dark matters seems to have
Well, I certainly can’t tell you to budget or not!

In my opinion, space tourism will happen. But space travel is HARD (and expensive), so the question is when will it happen? And all bets are off: over my lifetime, there have been promises of space tourism “within 10-20 years”; and I’m still waiting!
Well, funny thing just announced (July 29th).... sub-orbital flight for \$250k.

#### osirus12

Hey Everyone!

I had such a great time with the last AMA that I decided to come back to answer some more astronomy questions!

If you're new here, allow me to introduce myself:

I'm an astrophysicist primarily interested in the environments of the galaxies hosting supermassive black holes (also known as Active Galactic Nuclei). I've worked with clusters of galaxies, and the atmospheres of giant and supergiant stars. Currently I'm a Program Director at the National Science Foundation (NSF), Division of Astronomical Sciences, responsible for the National Radio Astronomy Observatory (NRAO); a part-time Professor at George Mason University in Fairfax, Virginia; and a Visiting Professor at the University of Colorado, Boulder, Colorado. And I'm a Fellow of the Royal Astronomical Society. Oh - and I LOVE all things Star Trek!!

I have a broad understanding of the field, but it’s vast (one could even say “astronomically” large), so I might need some time to find the answer.

Also, there may be lots of questions I can’t answer, because I don’t know – and maybe the answer isn’t yet known (that’s a fun part about astronomy – lots of unknowns still). Please keep this in mind.

As always, I will do my best, but I may not be able to answer all of the questions.

And, any opinions, findings, conclusions, or recommendations presented in my answers are only mine and do not necessarily reflect the views of the National Science Foundation.

Let's have some (more) fun!

Dr Joe

P.S. If you like the virtual background I've got in my photo below, liven up your next Zoom call with this and more incredible imagery from the NSF!

Hey Everyone!

I had such a great time with the last AMA that I decided to come back to answer some more astronomy questions!

If you're new here, allow me to introduce myself:

I'm an astrophysicist primarily interested in the environments of the galaxies hosting supermassive black holes (also known as Active Galactic Nuclei). I've worked with clusters of galaxies, and the atmospheres of giant and supergiant stars. Currently I'm a Program Director at the National Science Foundation (NSF), Division of Astronomical Sciences, responsible for the National Radio Astronomy Observatory (NRAO); a part-time Professor at George Mason University in Fairfax, Virginia; and a Visiting Professor at the University of Colorado, Boulder, Colorado. And I'm a Fellow of the Royal Astronomical Society. Oh - and I LOVE all things Star Trek!!

I have a broad understanding of the field, but it’s vast (one could even say “astronomically” large), so I might need some time to find the answer.

Also, there may be lots of questions I can’t answer, because I don’t know – and maybe the answer isn’t yet known (that’s a fun part about astronomy – lots of unknowns still). Please keep this in mind.

As always, I will do my best, but I may not be able to answer all of the questions.

And, any opinions, findings, conclusions, or recommendations presented in my answers are only mine and do not necessarily reflect the views of the National Science Foundation.

Let's have some (more) fun!

Dr Joe

P.S. If you like the virtual background I've got in my photo below, liven up your next Zoom call with this and more incredible imagery from the NSF!

good day dr.joe im new and really would like learn more from u

#### osirus12

Hey Everyone!

I had such a great time with the last AMA that I decided to come back to answer some more astronomy questions!

If you're new here, allow me to introduce myself:

I'm an astrophysicist primarily interested in the environments of the galaxies hosting supermassive black holes (also known as Active Galactic Nuclei). I've worked with clusters of galaxies, and the atmospheres of giant and supergiant stars. Currently I'm a Program Director at the National Science Foundation (NSF), Division of Astronomical Sciences, responsible for the National Radio Astronomy Observatory (NRAO); a part-time Professor at George Mason University in Fairfax, Virginia; and a Visiting Professor at the University of Colorado, Boulder, Colorado. And I'm a Fellow of the Royal Astronomical Society. Oh - and I LOVE all things Star Trek!!

I have a broad understanding of the field, but it’s vast (one could even say “astronomically” large), so I might need some time to find the answer.

Also, there may be lots of questions I can’t answer, because I don’t know – and maybe the answer isn’t yet known (that’s a fun part about astronomy – lots of unknowns still). Please keep this in mind.

As always, I will do my best, but I may not be able to answer all of the questions.

And, any opinions, findings, conclusions, or recommendations presented in my answers are only mine and do not necessarily reflect the views of the National Science Foundation.

Let's have some (more) fun!

Dr Joe

P.S. If you like the virtual background I've got in my photo below, liven up your next Zoom call with this and more incredible imagery from the NSF!

what is a quasar and does it mingle with in the black hole of space and time

jchamot

#### FrankT

When light enters our atmosphere, it slows down from speed in vacuum. There are particles bombarding our atmosphere which do not interact the same as light, some may not slow down as much as light does, or some may not slow down at all. Relatively speaking, those particles are travelling at superluminal speed inside our atmosphere. Is it possible that Cherenkov Effect of them is making our sky blue?

jchamot

#### Deryk Houston

I'd like to know if anyone has passed the light from the most distant stars through the slits in a double slit experiment. I'm curious if they behave the same way as any other light which gives the pattern we see when we do that experiment. Hard to believe that such ancient light would not be altered in some way after travelling through force fields, areas of massive gravity pulls, heated gases, other galaxies and debris etc etc, and that it might be telling us revealing information about about light that moves through that much space and time.

jchamot

#### DrJoePesce

Verified Expert
what is a quasar and does it mingle with in the black hole of space and time

Hello Osirus12! Thanks for being here!

A quasar is a subclass of objects collectively known as Active Galactic Nuclei, or AGN. Astronomers like to be descriptive in their names, and AGN is a classic example!

AGN, and hence quasars, are galaxies that host a super massive black hole in their centers, their nuclei. It seems all large galaxies host super massive black holes in their nuclei, but not all of them are “feeding”, that is large quantities of material (mostly gas, but also stars) falling into the black hole. The black hole in the center of our Milky Way galaxy is not feeding in this way. When large quantities of material fall into the black hole, we say the black hole is “active” – hence the name Active Galactic Nuclei.

Let’s look a bit more closely at what happens when material falls into the black hole. First of all, matter doesn’t fall directly onto (and into) the black hole. Rather, it forms a disk of material that circles the black hole, and then spirals into the black hole. We call this disk the accretion disk. Accretion disks around super massive black holes rotate very rapidly (a large fraction of the speed of light), and the material in the disk is heated to very high temperatures (billions of degrees). The interaction between the accretion disk and the black hole is complex, and not well understood. But there is probably a strong and complex magnetic field threading up through the accretion disk. The magnetic field probably gets twisted above and below the rotation axes of the black hole, as the black hole and accretion disk rotate. Charged particles (protons and electrons) can then get trapped in the magnetic field and squirted out in very tight structures called jets. The material has a lot of energy and the jets are very powerful and can extend into (and even beyond) the surrounding galaxy. We are still learning about jets and don’t fully understand how they are launched and powered (especially over large distances).

This is the picture of an AGN.

Again, when the black hole is not feeding, there might not be an accretion disk, and there aren’t jets – the black hole is not active. In fact, MOST galaxies are NOT active – AGN are a small subset of all galaxies, and were more common in the past, indicating that black hole feeding isn’t a continuous thing, and it was probably easier to dump matter into the centers of galaxies when galaxies were closer together in the past.

AGN have all sorts of different “flavors” or types. Quasars are one type; radio galaxies are another. Others are called BL Lacertae objects, Seyfert galaxies, etc. etc. One model is that they are all the same type of object (more or less), with the “central engine” as I described above, and the differences between the types are caused by how we view the jet: Do we see it face on, or edge on, or somewhere in between. If this is model is correct, it explains the differences between the different types of AGN.

jchamot

#### MasterOgon

##### Sci fi space cyberpunk artist
Hello! I have found one misunderstanding in physics. I was found that the asymmetric vibrations of the object in homogeneous - liquid and gaseous media lead to the formation of a wave medium in which two oppositely directed waves of different forces, made alternately, exist simultaneously by inertia and create a pressure difference leading to uneven the release of thermal energy from the environment in the form of a vortex, pushing the object.

But it is generally accepted that such an object should move in the opposite direction. Although this applies to aerohydrodynamics, it cannot but affect the understanding of other fundamental processes. Unfortunately, this information is still very little known. There are many questions, but I will be grateful if you just write your opinion on this matter.
Here in more detail and there are links to videos and articles:

#### DrJoePesce

Verified Expert
When light enters our atmosphere, it slows down from speed in vacuum. There are particles bombarding our atmosphere which do not interact the same as light, some may not slow down as much as light does, or some may not slow down at all. Relatively speaking, those particles are travelling at superluminal speed inside our atmosphere. Is it possible that Cherenkov Effect of them is making our sky blue?

Hello FrankT – and thanks for the question!

You are correct that the speed of light, in a medium (like our atmosphere) can be slower than the speed of light in a vacuum. And that things (primarily charged particles) can travel faster than light IN THE MEDIUM (but not faster than light in vacuum, which is the universal speed limit). When these charged particles (called cosmic rays) travel through our atmosphere, they produce what you correct note is called Cherenkov radiation, which is typically blue photons. Cosmic rays are bombarding our atmosphere constantly, but the amount is relatively low. So, the blue of the sky is not affected much by these Cherenkov photons. Rather, the blue of the sky is caused by refraction of the Sun’s light by the atmosphere. Blue light is, preferentially scattered (compared to red light), as sunlight passes through the atmostphere (this is why sunsets and sunrises can appear very red; the blue light has been scattered away). That blue light is easily scattered in the atmosphere and so appears to come from everyone – making the sky blue.

FrankT and jchamot

#### DrJoePesce

Verified Expert
I'd like to know if anyone has passed the light from the most distant stars through the slits in a double slit experiment. I'm curious if they behave the same way as any other light which gives the pattern we see when we do that experiment. Hard to believe that such ancient light would not be altered in some way after travelling through force fields, areas of massive gravity pulls, heated gases, other galaxies and debris etc etc, and that it might be telling us revealing information about about light that moves through that much space and time.

Thanks for the question Deryk Houston. Photons are photons. So there are no fundamental changes to the photon, or underlying laws of physics (as far as we can tell, and we’ve tested this wherever and whenever possible). That’s not to say photons are not affected by things as they travel through the universe. Mostly how they are affected depends on what type of photon they are (visible light, infrared, x-ray, radio, etc.). The ways they can be affected include some of the following:
• They can be scattered by gas and (mostly) dust. This affects *mostly* (but not only) the shorter wavelength visible-light photons (that is blue light – see my response about the color of the sky). When this scattering is caused by the gas and dust between the stars in galaxies, we call it interstellar reddening, causing more distant objects to appear redder than they really are.
• They can be absorbed by gas. Different wavelengths of light are absorbed by different things and in different amounts. Absorption can dim a distant astronomical object. A local example of absorption is our atmosphere. Luckily for us, high-energy photons (gamma-rays, x-rays, and some ultraviolet rays) are absorbed by the atmosphere and don’t pass through to the surface. Millimeter-wave radio photons are absorbed by water vapor in the atmosphere. Very-long wavelength radio photons are reflected by the ionosphere, etc. This sort of absorption occurs in space too.
• Radio photons can be affected by magnetic and electric fields in galaxies.
• All these have to be understood and, if we are observing a distant astronomical object that can be affected by any of these, corrections have to be made.
And finally, as photons fly through an expanding universe, their wavelengths are stretched – this is the so-called cosmological redshift. The classic example of this is the Cosmic Microwave Background radiation that is a fossil from a period when the universe was very young. These photons that permeate the universe now have very low energy and they are detected with radio telescopes. But when they were “new” they had much higher energies. Over the vast amounts of time they have been travelling through the expanding universe, they became lower and lower energy because their wavelengths were stretched as they went.

jchamot

#### Soham Dutta Roy

Just a question Dr. Joe; It is a known fact that all forms of EM waves travel at the relative speed of light, including radio waves, Infrared waves as well as visible light. But light itself takes some billions of years to reach us from the other parts of the galaxy, even more so from other galaxies, so isn't it obvious that whenever we look up at the sky searching for other forms of life out there through radio detection as well as visual through the Hubble space telescope, we are looking at the distant past? Should'nt the planets and stars we search for life be in the past? So what if another alien civilization started with us at the exact relative time we evolved in another part of our own galaxy wouldn't we be cut off from it for billions or so years cause of the literal Light Speed Barrier? Does science have any safeguards against this? Would the Fermi Paradox still hold if there were aliens in a neighbouring star system but we were cut off by this speed barrier?

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jchamot

#### VVet1968

The entropy – disorder – of the ENTIRE universe will increase, because it is a closed system. In local regions, however, there can be violations of the 2nd law, as long as overall the entropy increases.

I’m not sure what that means for black holes in the future. The expansion of the universe, in particular in the distant future, will play a bigger role in that “stuff” will eventually be too far apart to fall into black holes.
Doesn't the 2nd law actually say that entropy cannot decrease? That's not really the same as saying it must increase. If all processes are reversible (just hypothetically speaking here), then total system entropy can stay the same, correct? I'm asking because I recently read in Quanta about the simulations of an ekpyrotic universe that Paul Steinhardt and others have been running. Those simulations indicate that a cyclic universe may be possible. The implication, though not discussed in the article, is that during collapse, entropy decreases to the same extent that it increased during expansion for a net entropy change of 0. Thanks!

#### DrJoePesce

Verified Expert
Just a question Dr. Joe; It is a known fact that all forms of EM waves travel at the relative speed of light, including radio waves, Infrared waves as well as visible light. But light itself takes some billions of years to reach us from the other parts of the galaxy, even more so from other galaxies, so isn't it obvious that whenever we look up at the sky searching for other forms of life out there through radio detection as well as visual through the Hubble space telescope, we are looking at the distant past? Should'nt the planets and stars we search for life be in the past? So what if another alien civilization started with us at the exact relative time we evolved in another part of our own galaxy wouldn't we be cut off from it for billions or so years cause of the literal Light Speed Barrier? Does science have any safeguards against this? Would the Fermi Paradox still hold if there were aliens in a neighbouring star system but we were cut off by this speed barrier?

Yes, you are correct Soham Dutta Roy: Because the speed of light is fast, but not infinitely fast, and takes time to travel, EVERY astronomical object we observe is seen in the past. The nearest astronomical object is the moon, and it is about 1.3 light seconds away (it takes light 1.3 seconds to travel from the moon to the Earth). So, when you look at the moon, you are seeing those features as they WERE 1.3 seconds ago. Other astronomical objects are, of course, much further away. Astronomy is a time machine! If we know how far away an object is, we know how far in the past we are observing it. This is all taken into consideration when try to understand astronomical objects.

As for intelligent extraterrestrials (if they exist): Yes, this why communication would be difficult – the distances are so great. Apart from light speed, the distances are so great and that makes travel extremely difficult too (without a science-fiction-like propulsion system allowing faster-than-light travel).

jchamot

#### Robotron

The work of Halton Arp (Harvard, Caltech) and Tom Van Flandern (Yale, Chief of the Celestial Mechanics Branch of the Nautical Almanac Office), and many others suggests that the "big bang" model of cosmology has major (often fatal) flaws. For example, see Van Flandern's list of the Top 30 Problems with the Big Bang (https://www.spaceandmotion.com/cosmology/top-30-problems-big-bang-theory.htm)

As you correctly pointed out in an earlier post, the hallmark of a useful scientific model is its ability to predict future observations. A model that misses badly in its predictions, or is so laden with adjustable parameters that it cannot be falsified, is an unscientific model.

Given this fundamental tenet of the scientific method, why is it that so many cosmologists retain undying faith in the "big bang" model? By any objective account, its record of prediction is very poor.

Surely, you will disagree with this assessment, but I think the record is clear. The BB needs multiple adjustable parameters to survive. Interested readers can reference the source I cited above for more information.

My question to you, Dr. Pesce, is a simple one: Is the "big bang" model falsifiable?

I have started forum threads before asking precisely this question and, despite dozens of responses, I have never heard a BB proponent give a straight answer on this question. I think this says a lot about the model. If no one can think of an observation that would invalidate the BB, isn't that a problem? I say it is. A gigantic one.

In response to my question, I hear people defend the model by saying, "well, the BB is not perfect, but there's no good alternative." I disagree. As TVF points out in the link above, static universe models fare well against the BB, without the requirement for inventions like dark matter. However, the point I will always make in response is that no one should accept a shoddy, non-predictive model simply because he can't come up with a better one. Shoddy is shoddy. A true scientist will be comfortable with no answer rather than the *wrong* answer.

So again I ask: what observation could cosmologists possibly make that would falsify the BB?

DrRaviSharma

#### DrRaviSharma

Dr Joe
1. Is the dark matter that slows spiral galaxies from collapsing the same as is found at accretion disc scales?
2. What evidence is there for dark matter in AGN and if it is same as in 1. above, does it slow down accretion discs matter from collapsing into black holes.
3. How does dark matter manifest alongside CMB and its inhomogenieties?
4. Dark energy and dark matter- they have interaction or any other relationship?
5. Are there alternate phenomena we know that are equivalent of dark energy, such as loss of matter in blackholes, rate of conversion of matter into energy, etc?

jchamot

#### Terracraft

So I have two batch of questions. The first ones are scientific and the 2nd batch of questions is more personal.

What do you think is outside our universe? What is our space expanding to?
How do black holes gain more mass because at a certain point in the gravity well even light stops?
What kind of an attitude would you take if you knew there was extraterrestrial species? Should we let them be or get to them? Would the risk be reasonable?
How can we trust reality? Even though we have the scientific method, some things probably can change.
How do you feel about the rate of scientific development? Could things be going too fast, say. We really don't understand what we have found and we put things to use too quickly?
Is climate change a immediate threat to us?
Should science and religion support each other or be their separate entities?
Is it okay to mix and match old and new ideas together to make something new?
Isn't existing in space (like how we already are) really dangerous? Like there's asteroids, massive black holes, space dust, solar rays...
Could we some day inhabit/ terraform other planets?
Would a dyson sphere be a good idea or even like really big solar panels closer to a star with some protection and some way of transforming down to a surface?
What do you think is the most optimal way to settle on a planet time/resource wise?
How many people would you need to run a new place like that and keep propagating?

Is it just chance that we are here or was it set to be by a fate of a sort or more like a deterministic approach A leads to B and so fourth since the beginning of the universe? We just happen to be in a Goldilocks zone?

What is your favorite Star Trek? Have you seen them all? I am currently watching the series Discovery after seeing the others.
What music do you like?
How did you get where you are now? Are you happy to be doing what you're doing? Has your family played part in it?
Why do you do what you do?
With that, have you had hard obstacles or personal loss. How have you got through that, how have you had kept a hope up in hard moments be it related to anything?
Do you have a favorite dish or something you eat a lot?
Do you exercise?
Do you have any hobbies besides the area of your expertise?
Have you read any good physics/astronomy books, what are they?
What about classical literature, e.g "The Greats"`?
How do you manage to work for long if you have to? What helps to keep you up?
*Oh also. What do you think about science youtube channels? Veritasium, Vsauce x, numberphile, etc etc?

Thank you for your time Joe. And all of you. Stay safe.

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#### Letterpressstandard@gmail

Hi Dr. Joe !
Here is a fun question related to Star Trek.
If Warp 1 is the speed of light, and Warp 9.9 is roughly 2000 times that, would not the Enterprises" 5 year mission equate to lifetimes depending on where the Enterprise happened to travel to ?
In such a scenario, would the Enterprise often meet with its more advanced progeny on its way back to Earth? As Mr.Scott asks in the rebooted Star Trek movie...."you're from the future? Are there still sandwiches?"

jchamot
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