I'm a phd student and proposed time on xrism. super cool to see it being discussed here. its the only instrument that can do the science i'm interested in...even with the lens cap lol
@@sixtysymbols I wish it was that simple. I see many people complaining about not getting notifications and/or getting unsubbed. I spend a lot of time on youtube, they even attributed me that silly prime number.
The key to see everything is to just directly check your subscriptions page, all the uploads from all your subbed channels show up there (for me at least). I've done that since shortly after I first created my account back in 2006, I don't know why it isn't more common...
Huge credit to JAXA for not giving up on getting this tech out into space. I can't even imagine how disheartening it must be to have their missions ruined by one thing or another, time after time. The fact that this detector gets a fraction of the signal it should, yet is still producing those images, kind of tells you why they've been so determined to make it happen. Definitely makes you wonder how good it would look without the stuck cover
I was a graduate student in the 90's in the group at University of Wisconsin-Madison that was developing the x-ray quantum calorimeters. Although I've been out of academia for more than two decades at this point, I'm thrilled that there's finally a satellite flying with those detectors. My advisor studies the interstellar medium and his team has made numerous observations with these detectors using sub-orbital "sounding" rocket flights, so these would have been doing science without the collaboration with JAXA, but it's gratifying that they picked it up for a major space telescope and stuck with the concept for all this time.
I love Mike's explanation of why the emission lines of heavier elements are much shorter than those of lighter ones. For a man who until recently didn't understand magnetic cooling he explained it well enough that I can at least run with it. Excellent.
Hey cool! Sixty Symbols is talking about the mission I work on! Even with its problems, everyone is still pretty excited about the kinds of data we'll be able to get with XRISM
9:58 measuring the energy by measuring temperature change due to single photons is such a pure brut force way of abusing calorimetric physics principles I LOVE IT
@@James-ls7ugheat is jusy energy. So if you messure the heat applied to the sensor (heat causes the temperature to rise so you can measure the temperature), you know how much energy was applied, i.e. the energy of the photon that hit the sensor, i.e. you know the wavelength of the light
This professor explains things so clearly and concisely - I bet anytime from a high school to a PhD student can easily understand what he is saying. Very fascinating topic.
I'm a couple of years past 50 and I've had my beard for over 30 years... apart from a few weeks that will not be spoken of... and Mike still has more hair on top of his head than I had when I started my beard. Well done, sir. Clicked for the lens cap, and as always learned many new and interesting things from Professor Merrifield. I'm now curious as to whether there is a possibility of, and demand for, a more efficient x-ray mirror.
And yes, space is hard. That's part of why it's taken us five decades to go back to the moon. It's also probably a major part of the Great Filter that explains the Fermi Paradox. I'm of the opinion that complex life like humans just can't survive the rigors of interstellar travel, and because space is so big, any other life that may exist is simply too far from us in either space or time or both to allow contact to be made; this tangent brought to you by the 'Contact' reference. 🙂
When JWST (I think) was getting fired up some smart ass had inserted an image into the boot-up stream that read: REMOVE LENS CAP BEFORE LAUNCH. I imagine several aneurysms were had in that moment. Today, that prank got some context -- and much funnier!
@@AKHILGEORGETHOMAS I looked it up. The instrument employs a multi stage system composed of 2 magnetic coolers, then a liquid helium tank, another magnetic cooler, a helium-based Joule-Thompson mechanical cooler, and finally mechanical Stirling coolers going to room temperature. So quite involved. However, there is research going on for magnetic cooling directly from room temperature. To my limited knowledge this is not very energy efficient (yet) and therefore unlikely to be used in satellites in the near future. PS: I forgot to say that the system should still work after the liquid helium has run out after 3 years (if nothing goes wrong). The JT and Stirling coolers should not lose their own working helium as that system is sealed unlike the liquid helium that very slowly boils off.
In general thermodynamics is a nice and broad theory "independent" from the underlying details. When I had my first thermodynamics class we learned the theory at the example of ideal gases and then in the exercise sessions we were told: Now do the same with magnetism - here are the base equations!
I like the “delivery” by Mike, is it? A lot of very interesting science and technology progress and some “very common” physics tools, hardly anybody has heard about, like magnetic cooling.
I'd like to see a Sixty Symbols about how we were able to get temperatures low enough to liquefy helium and other gases - and a Periodic Videos on how we used those techniques to isolate those gases from the air.
If I am not mistaken, in the IR and FIR instruments for satellites, they also used adiabatic cooling of salts for the later stages of the process. The Kepler satellite (formerly known as FIRST) did use that kind of cooling. If it did not, we certainly did have adiabatic colling dewars in the physics departmet lab where we tested the instruments to be installed in that staellite.
They can't get the lens cap off, but, luckily, it's an x-ray camera and can see through lens caps. That other part of the spectrum? We'll just call it far UV and say it's some other satellite's problem.
I love the point at the end that theorists are gonna have to work harder now they actually have good data to work from. Never thought about it that way but it makes sense that your theories only really need to be as good as the current observations.
The magnetic cooling reminds me of stretching a rubber band quickly, holding it there for a few minutes, then releasing it. It heats up when you stretch it, the heat cools as the rubber band is held, and it cools down quickly once released. I'm pretty sure there's a video online of someone making a refrigerator that works based on rubber band cooling.
Regular refrigeration also works like that. Whne you compress gaseous refrigerant enough, they condense into liquid and release heat. Put the liquid somewhere and remove the pressure and it evaporates, absorbing a lot of heat.
I'm still waiting for a "coldness 4-vector" to enter common use (the mu-th component of the coldness 4-vector would be the partial derivative of entropy with respect to the mu-th component of 4-momentum). The time coldness is just the reciprocal of the temperature.
15:01 Cheers for quoting »Contact«, one of my favorite books (Carl Sagan!) and fav movies. Why build one when you can have to for twice the price? Indeed!
This is not a shot a JAXA, we all know space is a tremendously difficult place to work, but… it’s a testament to the amazing engineers at NASA and JPL and all the other agencies/companies that they work with, that things like James Webb just work on the first try. I know people complain when projects are delayed by years and years, but if that’s what it takes to get it right, then so be it.
Wow what a great leap in the S/N ratio, compared to Chandra. Go JAXA! PS with this recond of technical difficulties - I'd rather kept the cap on. If it still works - don't fix it.
Its amazing work ! Don't take me the wrong way when I say I hope i can live long enough to sense the universe in all its glory for myself. Elons, along ways away from hooking us up to that one .😮❤😂 But it does bring the anylitical & image dualistic mind scale of order into the fact that granting deterministic time on such a subjective medium of complexity that we have to question our interpretations on surly. Of course, as an ease of access for astronomical distances & and modeling it's fine. But trying to unify it with all other disciplines really brings back my childhood hearing the advocates of the day against the snow on my TV. Lol As someone with my American ancestry in my veins who lived through compromises of 1900s structuralism it can't be said we didn't compromise and try to accommodate what the greater world wanted on this topic
Reminds me of the Soviet probe they send to Venus to successfully land and making a chemical analysis of the lens cap. Given how hellish the surface of Venus is it's an achievement.
Could you do a new video on the state of dark matter particle searches? It looks like the last one you did was a decade and a half ago. Many of the current generation of liquified cryogenic noble gas based detectors are becoming so exquisitely sensitive to just about anything bumping into them that they're soon coming up against the background elastic coherent neutrino scattering noise floor. When they hit the limit, what then? Is it the end of dark matter searches?
When I started here, all there was was swamp. Other kings said I was daft to build a castle on a swamp…but I built it all the same, just to show 'em! It sank into the swamp…so, I built a second one. That sank into the swamp. So I built a third one. That burned down, fell over, then sank into the swamp. But the fourth one...stayed up!
imagine you want to take photos but lens cap is on, and you go like fffffuuuuuuuu....ck!!! but your camera is in space and you can't take the sucker off
That explanation of magnetic cooling was really bad. It left the biggest question unanswered - if we heat the mass, and then cool it again, repeating in a cycle - how does it end up cooler in the process? If entropy is to be conserved, why is the final temperature lower than the start temperature? I had to read the Wikipedia article to finally understand what's happening. Apparently, you make make sure that the heated mass is cooled down to initial temperature by radiating *away* the extra heat Q added to it, while still being locked in the magnetic field. You have to make sure you radiate the heat away from the object you want to cool down. Then you turn off the magnetic field, which then unaligns the magnetic field of the atoms, but since the total entropy needs to be conserved, the mass cools down even further. The reason why you want to do this quickly is simply because you want to keep total entropy constant.
I just came for the lens cap, but ended up learning a tremendous amount about x-ray astronomy. Well done!
Ha. Minute 25 no lens cap
Do you think whales feel more communist if we put them in an elliptical low earth orbit?
@@evanm6739 I hope I never forget this comment
Seriously I could listen to Mike talk all day!
He's married, f*** off!
Agreed, what a fantastic teacher.
You've underplayed JAXA quite a lot. They've brought comet samples back to earth, and have landed a craft on the moon, although it fell over.
I'm a phd student and proposed time on xrism. super cool to see it being discussed here. its the only instrument that can do the science i'm interested in...even with the lens cap lol
I’d love to hear more! What type of science are you interested in, or is there a paper I can read?
@@Ranovin Seconded!
lets send elon to take the cap off...
ok?
Holy crap. It's been years since I got a Sixty Symbols recommendation.
Get those notifications on. 🔔
@@sixtysymbols "Hit that holler horn!"
@@sixtysymbols I wish it was that simple. I see many people complaining about not getting notifications and/or getting unsubbed. I spend a lot of time on youtube, they even attributed me that silly prime number.
@@sixtysymbols last thing anyone wants: more notifications, more flashing numbers
The key to see everything is to just directly check your subscriptions page, all the uploads from all your subbed channels show up there (for me at least). I've done that since shortly after I first created my account back in 2006, I don't know why it isn't more common...
Huge credit to JAXA for not giving up on getting this tech out into space. I can't even imagine how disheartening it must be to have their missions ruined by one thing or another, time after time. The fact that this detector gets a fraction of the signal it should, yet is still producing those images, kind of tells you why they've been so determined to make it happen. Definitely makes you wonder how good it would look without the stuck cover
I was a graduate student in the 90's in the group at University of Wisconsin-Madison that was developing the x-ray quantum calorimeters. Although I've been out of academia for more than two decades at this point, I'm thrilled that there's finally a satellite flying with those detectors. My advisor studies the interstellar medium and his team has made numerous observations with these detectors using sub-orbital "sounding" rocket flights, so these would have been doing science without the collaboration with JAXA, but it's gratifying that they picked it up for a major space telescope and stuck with the concept for all this time.
I love these walkthroughs of how we've come to current best practice and all the problems scientists have had to overcome. More please.
I love Mike's explanation of why the emission lines of heavier elements are much shorter than those of lighter ones. For a man who until recently didn't understand magnetic cooling he explained it well enough that I can at least run with it. Excellent.
Hey cool! Sixty Symbols is talking about the mission I work on! Even with its problems, everyone is still pretty excited about the kinds of data we'll be able to get with XRISM
Are you the person that forgot to take the lens cap off?
Very very cool :)
ok?
9:58 measuring the energy by measuring temperature change due to single photons is such a pure brut force way of abusing calorimetric physics principles I LOVE IT
Is there an easy way to describe other than this 😂 I want to know!
You mean photons.
@@James-ls7ugheat is jusy energy. So if you messure the heat applied to the sensor (heat causes the temperature to rise so you can measure the temperature), you know how much energy was applied, i.e. the energy of the photon that hit the sensor, i.e. you know the wavelength of the light
Great to see another video with Prof Merrifield!
I don't want to use the word clickbait bc this wasn't, but titling the video that way after he saved that for the end was genius!
This professor explains things so clearly and concisely - I bet anytime from a high school to a PhD student can easily understand what he is saying. Very fascinating topic.
"It's very cool" referring to magnetic cooling, nice.
Also, "they developed this technology but no satellite, so that didn't fly"
Yes, he was quite sly with the puns. It was delightful.
I learned here that space engineering is expensive and difficult, but perseverance gets results even if you have to wait for decades to get them.
Merrifield and Haran , what a great team.
Second that!
❤❤❤❤❤❤❤❤
I'm a couple of years past 50 and I've had my beard for over 30 years... apart from a few weeks that will not be spoken of... and Mike still has more hair on top of his head than I had when I started my beard. Well done, sir.
Clicked for the lens cap, and as always learned many new and interesting things from Professor Merrifield. I'm now curious as to whether there is a possibility of, and demand for, a more efficient x-ray mirror.
And yes, space is hard. That's part of why it's taken us five decades to go back to the moon. It's also probably a major part of the Great Filter that explains the Fermi Paradox. I'm of the opinion that complex life like humans just can't survive the rigors of interstellar travel, and because space is so big, any other life that may exist is simply too far from us in either space or time or both to allow contact to be made; this tangent brought to you by the 'Contact' reference. 🙂
When JWST (I think) was getting fired up some smart ass had inserted an image into the boot-up stream that read: REMOVE LENS CAP BEFORE LAUNCH. I imagine several aneurysms were had in that moment. Today, that prank got some context -- and much funnier!
❤❤❤❤❤❤
Hahah, Didn't know about that but it is super funny 😅👌
Very cool stuff, the magnetic cooling cycle looked very similar to regular refrigerator cooling system.
Yes so similar to a carnot cycle. I'm interested in what he meant by the heat energy getting radiated off. Do they still use liquid He?
@@AKHILGEORGETHOMAS I looked it up. The instrument employs a multi stage system composed of 2 magnetic coolers, then a liquid helium tank, another magnetic cooler, a helium-based Joule-Thompson mechanical cooler, and finally mechanical Stirling coolers going to room temperature. So quite involved. However, there is research going on for magnetic cooling directly from room temperature. To my limited knowledge this is not very energy efficient (yet) and therefore unlikely to be used in satellites in the near future.
PS: I forgot to say that the system should still work after the liquid helium has run out after 3 years (if nothing goes wrong). The JT and Stirling coolers should not lose their own working helium as that system is sealed unlike the liquid helium that very slowly boils off.
In general thermodynamics is a nice and broad theory "independent" from the underlying details. When I had my first thermodynamics class we learned the theory at the example of ideal gases and then in the exercise sessions we were told: Now do the same with magnetism - here are the base equations!
I like the “delivery” by Mike, is it? A lot of very interesting science and technology progress and some “very common” physics tools, hardly anybody has heard about, like magnetic cooling.
I love how the helium entropy cooling process is so similar to our everyday refrigeration. Yet in a totally different way!
Love the Contact reference. I do use that one more often than I probably should.
Glad to see I'm not the only one. That and "Small moves, Ellie. Small moves."
ok?
As a fellow beardy, tell Mike that full set is magnificent
I'd like to see a Sixty Symbols about how we were able to get temperatures low enough to liquefy helium and other gases - and a Periodic Videos on how we used those techniques to isolate those gases from the air.
Thanks. This was all new to me. I found it very informative and well explained.
Super interesting. What a fantastic teacher.
If I am not mistaken, in the IR and FIR instruments for satellites, they also used adiabatic cooling of salts for the later stages of the process. The Kepler satellite (formerly known as FIRST) did use that kind of cooling. If it did not, we certainly did have adiabatic colling dewars in the physics departmet lab where we tested the instruments to be installed in that staellite.
Wonderful! Thanks for making these videos
Random observation: At 00:01 the "Sixty Symbols" logo looks sooo confusing when you are Greek
14:50 If I remember correctly, it would have cost only 40% more to build a second JWST in parallel with the first.
They can't get the lens cap off, but, luckily, it's an x-ray camera and can see through lens caps. That other part of the spectrum? We'll just call it far UV and say it's some other satellite's problem.
This lens cap has just created a schism in xray astronomy
Thanks! That was extremely interesting with all the explanations how the instruments work!
Świetna i bardzo ciekawa rozmowa. Dziękuję!
I love the point at the end that theorists are gonna have to work harder now they actually have good data to work from. Never thought about it that way but it makes sense that your theories only really need to be as good as the current observations.
Thank you...fascinating ( and must have been heartbreaking for so many.)
The magnetic cooling reminds me of stretching a rubber band quickly, holding it there for a few minutes, then releasing it. It heats up when you stretch it, the heat cools as the rubber band is held, and it cools down quickly once released. I'm pretty sure there's a video online of someone making a refrigerator that works based on rubber band cooling.
Regular refrigeration also works like that.
Whne you compress gaseous refrigerant enough, they condense into liquid and release heat. Put the liquid somewhere and remove the pressure and it evaporates, absorbing a lot of heat.
Right on. Thanks for sharing.
Now i'm interested in the relationship between Entropy/Temperature and Time/Temperature.
I'm still waiting for a "coldness 4-vector" to enter common use (the mu-th component of the coldness 4-vector would be the partial derivative of entropy with respect to the mu-th component of 4-momentum). The time coldness is just the reciprocal of the temperature.
Thank you so much for these insights!
And someone has been cleaning his shelves ;)
15:01 Cheers for quoting »Contact«, one of my favorite books (Carl Sagan!) and fav movies.
Why build one when you can have to for twice the price? Indeed!
Turns out dark matter was lens caps all along...
@@20cmusic hu·mor /ˈ(h)yo͞omər/
noun
the quality of being amusing or comic, especially as expressed in literature or speech.
No indeed. They can definitely see that lens cap.
🤣Funny one.
Absolutely Fabulous technology and achievements.
Wait if you use the ambient temperature to get rid of the heat then how do you go lower than a single step of the cycle?
what happened to the old school way when they send specialists up who remove the stuck lens cap? that would be a nice mission for orbitersim :P
Great vid, cheers.
mike for president!
Absolutely lovely video!
Thanks. Very well explained.
Have they tried letting the telescope spin kinda fast and see if the centrifugal force helps dislodge the lenscap?
Just a little on that Contact reference: I've always thought that John Hurt's character is eerily reminiscent of Neil Sloane...
"It's very cool" Yeah, you ain't kidding. Milikelvins above absolute zero is VERY cool.
This is not a shot a JAXA, we all know space is a tremendously difficult place to work, but…
it’s a testament to the amazing engineers at NASA and JPL and all the other agencies/companies that they work with, that things like James Webb just work on the first try. I know people complain when projects are delayed by years and years, but if that’s what it takes to get it right, then so be it.
I love that at some point he took his old brass telescope to work & parked it on the filing cabinet 🤓
The camera on that thing is so cool. They can do all that with 36 pixels.
Very interesting. 12:46 It's very cool.... lol!
Great video but please sort the static background noise
12:45 "it's very cool" Brady didn't laugh at his joke!
That’s amazing, thanks!
love this!
I hope Mike's colleagues from the Physics department dont watch this video and hear him talking about "degrees" Kelvin... 😱
Huh, I learned something new today.
"Electron Splat" is a confirmed scientific term now for X-Ray photon detection I am happy.
Mike could explain accretion physics to my grandma if he wanted to
Love this topic
This telescope has strong Venera energy
that really low iron spike (compared to si) would that mean the star went boom pretty fast when it started fusing iron? or is that typical?
12:45 it's very cool... such a pun
Mike Merrifield: the Attenborough of astronomy.
I got your Contact reference, Brady.
Magnetic cooling... Adiabatic nuclear demagnetisation! Come to Lancaster and do a whole video on our cooling techniques and fridges :)
Merrifield, "...it's very cool."
3:18 I have to say, "Reasonably Close and Reasonably Hot" sounds like the title of a movie.
did you get a new camera? looks crrrrrrisp
I thought that you would go for the Monty Python sketch about the castles falling into the swamp as the Easter egg…😂
Wow what a great leap in the S/N ratio, compared to Chandra.
Go JAXA!
PS with this recond of technical difficulties - I'd rather kept the cap on.
If it still works - don't fix it.
Its amazing work ! Don't take me the wrong way when I say
I hope i can live long enough to sense the universe in all its glory for myself. Elons, along ways away from hooking us up to that one .😮❤😂
But it does bring the anylitical & image dualistic mind scale of order into the fact that granting deterministic time on such a subjective medium of complexity that we have to question our interpretations on surly.
Of course, as an ease of access for astronomical distances & and modeling it's fine. But trying to unify it with all other disciplines really brings back my childhood hearing the advocates of the day against the snow on my TV. Lol
As someone with my American ancestry in my veins who lived through compromises of 1900s structuralism it can't be said we didn't compromise and try to accommodate what the greater world wanted on this topic
Reminds me of the Soviet probe they send to Venus to successfully land and making a chemical analysis of the lens cap. Given how hellish the surface of Venus is it's an achievement.
I think the x-ray astronomy team needs to investigate and look for an undercover agent from the IR- or Radio-telescope teams sabotaging their efforts.
Could you do a new video on the state of dark matter particle searches? It looks like the last one you did was a decade and a half ago. Many of the current generation of liquified cryogenic noble gas based detectors are becoming so exquisitely sensitive to just about anything bumping into them that they're soon coming up against the background elastic coherent neutrino scattering noise floor. When they hit the limit, what then? Is it the end of dark matter searches?
That's some Monty Python level of a cursed mission lol. But the fourth one -stayed up- gave back comprehensible data.
When I started here, all there was was swamp. Other kings said I was daft to build a castle on a swamp…but I built it all the same, just to show 'em! It sank into the swamp…so, I built a second one. That sank into the swamp. So I built a third one. That burned down, fell over, then sank into the swamp. But the fourth one...stayed up!
The development of space technology is very rapid.
Oh that must be so frustrating for the fellows working on these projects!
Magnetic cooling: It *is* very cool :D
That SN remnant looks like two brine shrimp squaring up for a fight.
imagine you want to take photos but lens cap is on, and you go like fffffuuuuuuuu....ck!!! but your camera is in space and you can't take the sucker off
That explanation of magnetic cooling was really bad. It left the biggest question unanswered - if we heat the mass, and then cool it again, repeating in a cycle - how does it end up cooler in the process? If entropy is to be conserved, why is the final temperature lower than the start temperature?
I had to read the Wikipedia article to finally understand what's happening. Apparently, you make make sure that the heated mass is cooled down to initial temperature by radiating *away* the extra heat Q added to it, while still being locked in the magnetic field. You have to make sure you radiate the heat away from the object you want to cool down. Then you turn off the magnetic field, which then unaligns the magnetic field of the atoms, but since the total entropy needs to be conserved, the mass cools down even further. The reason why you want to do this quickly is simply because you want to keep total entropy constant.
What if you just take an optical telescope, but stretch the space in front of it as the light is coming in, so the xrays become visible light? :p
16:15
Woohoooo 🎉🎉🎉
I always wondered how they got things cooler than liquid helium.
Sunglasses
Couldn't they calibrate it using a star they already got many historical readings using previous telescopes?
Next time, soft X-rays, next time!
Let's see who gets that reference 🙂
I'm thinking of the SNL fake ad where Stevie Wonder takes the lens cap off of the guy's camera.
Cool
Should our AC’s on earth run off of magnets???
Thats what I want to know.
It's like the universe tried really hard to make sure we can't see xrays......
Chrism is consecrated anointing oil.
X ray is crazy
It's all fun and games until an electron jumps from one energy state to another.