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2022-12-14: How Can Matter Be BOTH Liquid AND Gas?

  • 19:18: ... brightness for an object like this, determined by the maximum amount of fuel you can pour in before the outgoing radiation stalls the fuel ...

2022-10-12: The REAL Possibility of Mapping Alien Planets!

  • 06:05: ... the Sun. More traditional propulsion methods that carry their own fuel have hard constraints   on payload size and acceleration ...

2022-06-30: Could We Decode Alien Physics?

  • 16:39: ... diffuse interstellar material as reaction  mass and fusion fuel for the slowdown phase.   Actually Tony Tee   seems ...

2022-06-01: What If Physics IS NOT Describing Reality?

  • 15:25: ... the mass and also rejuvenates the   star because more hydrogen fuel gets pumped into  the fusion core. It’s believed that the oddly ...

2022-05-18: What If the Galactic Habitable Zone LIMITS Intelligent Life?

  • 03:40: ... inward   crush for 5 billion years now, and has  enough fuel for about 5 billion ...

2021-12-20: What Happens If A Black Hole Hits Earth?

  • 06:56: ... around a black hole can radiate before radiation pressure cuts off the fuel. ...

2021-12-10: 2021 End of Year AMA!

  • 00:02: ... around and it um manages to um to accelerate without without ejecting fuel um that's been solidly debunked at this point um but they've also been ...

2021-02-17: Gravitational Wave Background Discovered?

  • 00:00: ... it's the metric tensor which describes that curvature remember a fuel is just something that takes on a numerical and maybe a vector value ...

2020-12-22: Navigating with Quantum Entanglement

  • 13:47: ... - either the core of a very massive star collapses after expending its fuel - that’s a type 2 supernova - or the remnant of a lower mass star - a ...

2020-12-15: The Supernova At The End of Time

  • 04:48: Once its nuclear fuel supply runs out, there would be no outward flow of energy to resist the gravitational crush.

2020-11-18: The Arrow of Time and How to Reverse It

  • 11:16: ... as part of their choice-making mechanics. They become informational fuel for our choices.. Now if those random numbers are not even in principle ...

2020-07-20: The Boundary Between Black Holes & Neutron Stars

  • 04:57: But when it ran out of fuel, gravity took over and the entire star collapsed.

2020-06-15: What Happens After the Universe Ends?

  • 12:28: ... forever of the previous universe, where exponential expansion was fueled by dark ...

2020-05-04: How We Know The Universe is Ancient

  • 12:59: ... time. There are other approaches to getting the necessary numbers to fuel the Friedman equations - and despite some intriguing conflicts - ...

2019-07-15: The Quantum Internet

  • 11:59: And there's absolutely no way that a bunch of fuel rods could do that.
  • 13:00: Nuclear fuel - typically uranium - is encased in graphite balls.

2019-07-01: Thorium and the Future of Nuclear Energy

  • 02:49: ... by boiling water The most common commercial power plants use uranium fuel, in particular the isotope Uranium-235 Uranium-235 has 92 protons and 143 ...

2019-03-20: Is Dark Energy Getting Stronger?

  • 07:07: They can have a huge range of energy output, depending on the mass of the black hole and how much fuel it’s getting.

2019-03-13: Will You Travel to Space?

  • 07:16: It's worth a quick word on. Obviously the space plane itself needs less fuel than a craft launched from the ground.
  • 07:28: ... more efficient than rockets at low altitude. As well as a combustible fuel as an energy source, rockets need to carry an oxidant to burn that fuel ...
  • 07:51: ... only need to carry the energy supply which is usually a combustible fuel, but could also eventually be electricity. In addition, an air-launch ...

2018-08-23: How Will the Universe End?

  • 00:27: ... the last star in the universe will expand, the final atoms of hydrogen fuel and settle quietly into a dim white dwarf before slowly fading to black ...

2018-08-01: How Close To The Sun Can Humanity Get?

  • 06:41: ... which can be even trickier than gaining speed and requires just as much fuel. ...

2018-06-27: How Asteroid Mining Will Save Earth

  • 05:22: ... are essential in everything from electronic components, batteries and fuel cells, magnets, as chemical catalysts and reagents, and in a huge range ...
  • 06:19: Water dissociates into hydrogen and oxygen, becoming rocket fuel, which is critical for shipping mined resources back to Earth.
  • 06:27: ... you have to carry all that return fuel on the initial launch vehicle, you have to massively cut back on the ...
  • 07:08: ... of these near-Earth asteroids can be accessed with relatively little fuel expenditure from Earth orbit, and these will be the target of the first ...
  • 08:26: This can be done with a gravitational tractor, which we talked about before, or with rockets fueled by the asteroid's own water supply.

2018-05-02: The Star at the End of Time

  • 02:21: ... more massive stars with their hotter cores burn through their fuel much, much more ...
  • 02:36: Stars less massive than the Sun burn through their fuel much more slowly.
  • 02:56: That means it's burning through its fuel 1,000 times less quickly.
  • 03:00: But it also has less fuel to burn, right?
  • 03:31: As a result, the Sun will only have access to 10% of its mass for fusion fuel.
  • 03:58: A red dwarf with 10% the Sun's mass has just as much fuel to burn as the Sun does, yet it burns it 1,000 times slower.
  • 06:00: ... with the last hydrogen fuel spent, the entire star will become composed of helium and will quietly ...

2018-03-07: Should Space be Privatized?

  • 10:37: Stimuli asked why stars get brighter as they age if their fuel is depleting.
  • 10:45: As the hydrogen fuel in the sun's core gets diluted by helium, the fusion rate does decrease and the core shrink.
  • 11:23: No new fuel is carried down to the core and the fusion products remain stuck there.
  • 11:36: But by the time a red dwarf finishes using its fuel, the entire star is made of helium.
  • 12:04: ... stars consume their fuel thousands of times more slowly than the sun, which means they can live ...

2018-02-21: The Death of the Sun

  • 02:01: But what are the prospects for our little planet after the sun runs out of fuel?
  • 02:14: That helium is useless as a fuel, at least for now, because helium fusion requires temperatures of around 100 million Kelvin.
  • 02:35: Soon, a thin shell of fresh hydrogen fuel around the dead core becomes hot enough to ignite.
  • 04:46: The core is resurrected with a vast new supply of fuel.

2018-01-24: The End of the Habitable Zone

  • 00:25: The sun is slowly burning through its fuel.
  • 00:36: But that fuel will run out, after which the sun will swell into a red giant and flash fry the earth.
  • 01:00: All stars brighten as they age and they deplete their fuel.
  • 01:06: Why does less fuel mean a brighter star?
  • 01:43: At that point, the sun had plenty of hydrogen fuel.
  • 01:49: As the sun's fuel gets diluted, you might expect fusion to slow down.
  • 03:01: ... a third again as large before it finishes burning it store of hydrogen fuel in around 5 billion ...
  • 09:47: ... perhaps we can hold out until the sun eventually exhausts its fuel and becomes a red giant expanding to consume the only home we've ever ...

2018-01-10: What Do Stars Sound Like?

  • 06:21: ... composition of the core, which tells us how much of the sun's hydrogen fuel source has already been burned into ...

2017-11-02: The Vacuum Catastrophe

  • 01:55: ... satisfy the Heisenberg uncertainty principle, the vacuum state of any fuel oscillation must be half of the tiny Planck constant times the frequency ...

2017-10-04: When Quasars Collide STJC

  • 05:27: ... separate knots of radio light in AGN jets, which can splatter as their fuel supply changes or as the jets smash into denser regions of the ...

2017-08-24: First Detection of Life

  • 03:55: Anthropogenic sources account for the other half, including burning fossil fuels, and, as Sagan puts it, flatulence from domesticated ruminants.

2017-07-19: The Real Star Wars

  • 11:27: ... the purpose of its destruction was to avoid the unlikely event of its fuel tank of toxic hydrazine from reaching the ...

2017-07-12: Solving the Impossible in Quantum Field Theory

  • 03:58: ... squiggle represents the quantized fueled excitation of the photon, and the connecting points, the vertices, ...

2017-05-31: The Fate of the First Stars

  • 05:04: Now, burning through 10 times the fuel at 10,000 times the rate, compared to the sun, means its life is 1,000 times shorter-- only 10 million years.

2017-01-25: Why Quasars are so Awesome

  • 08:12: However, the same rich gas supplies that fueled those starbursts also gave rise to the epoch of quasars.
  • 09:45: ... black holes merge, the violence will deliver one last wave of fuel to the combined galactic core, and a new quasar will shine forth, ...

2017-01-19: The Phantom Singularity

  • 01:21: According to Newton's law, in order to fuel that infinite gravitational acceleration you need to get zero distance from an object's center of mass.
  • 09:17: And once inside, inward spatial movement continues to be the only way to fuel the ticking of an object's proper time clock.

2016-11-16: Strange Stars

  • 01:44: They are created in the final collapse of a very massive stellar core after it has exhausted all possible fusion fuel supplies.

2016-10-19: The First Humans on Mars

  • 01:10: The booster then returns to its launchpad and is loaded with a giant fuel tank.
  • 01:14: It relaunches and delivers to the orbiting spaceship enough fuel for the four-month journey to Mars.
  • 01:25: That means many return trips to Mars, but it also allows the booster to carry the spaceship and the fuel in separate launches.

2016-09-14: Self-Replicating Robots and Galactic Domination

  • 05:13: Fusion engines might be a good candidate, because the fuel is abundant everywhere.
  • 05:49: It builds fuel collectors-- maybe orbiters to harvest deuterium or tritium from gas giant atmospheres.

2016-08-24: Should We Build a Dyson Sphere?

  • 06:39: Only 0.7% of the rest mass of the ingoing hydrogen fuel at the sun's core is converted to energy.
  • 07:00: What if instead of converting 0.7% of fuel rest mass into energy we could achieve 100% efficiency?
  • 07:10: But currently it takes more energy to create the anti-matter fuel than we get back out.

2016-05-04: Will Starshot's Insterstellar Journey Succeed?

  • 01:44: Even for next generation fuels, like certain types of fusion, the propellant weight can be most of the craft weight at launch.
  • 01:53: So the fuel is mostly accelerating itself.

2016-04-06: We Are Star Stuff

  • 04:31: And all of that hydrogen and helium would later become the fuel for the later formation of stars.
  • 06:03: And each inner shell rages through its available fuel quicker than the previous.
  • 06:08: ... hydrogen core, when that core is entirely silicon, it burns through that fuel in only a day, leaving a core of ...
  • 07:38: In this explosion, all those elements are spread into interstellar space, providing fuel for later stars to form.

2016-03-16: Why is the Earth Round and the Milky Way Flat?

  • 08:49: These things are so huge and spread out, they barely fuel their own gravity, and they collapse very, very slowly.

2015-12-09: How to Build a Black Hole

  • 11:35: ... actually, it's going to take the same amount of fuel to pull by a gravitational tractor as it would to push an asteroid by ...

2015-11-25: 100 Years of Relativity + Challenge Winners!

  • 02:13: ... desired change in position and then the rocket equation to see how much fuel we'll need to achieve ...
  • 03:10: Well, we know that the spacecraft's mass is changing because it needs to burn fuel to accelerate.
  • 03:16: But we can just calculate the average acceleration based on the average mass of the spacecraft plus fuel over the seven years.
  • 03:34: So the mass that we're going to calculate is the average mass of the spacecraft in fuel over the seven years.
  • 04:18: It also gives us the acceleration experienced by Apophis due to the mass of the spacecraft and the fuel.
  • 04:27: That 30 billion kilograms will come back later when we need to figure out how much fuel we need.
  • 04:56: But what about the fuel requirements?
  • 05:01: ... delta v, the total change in velocity, to the exhaust velocity of the fuel and the ratio of fueled to unfueled or wet to dry spacecraft ...
  • 05:36: The wet mass is then just Apophis' mass plus the fuel mess.
  • 05:40: Rearranging all of this, we get this equation for the ratio of fuel mass to asteroid mass.
  • 06:34: Putting this together, we get a ratio of fuel mass to asteroid mass of 5.3 by 10 to the minus 7.
  • 06:41: So the fuel mass we need is around 16 metric tons, which is great because that's only 1% of the spacecraft mass.
  • 07:11: ... regular rocket fuel has less than 1% of the exhaust velocity of our pulsed future drive and ...

2015-11-11: Challenge: Can you save Earth from a Killer Asteroid?

  • 01:38: How massive would the spacecraft, including the fuel, need to be?
  • 01:54: ... to the propellant exhaust velocity and the ratio of wet to dry, or fueled to unfueled, ...

2015-10-22: Have Gravitational Waves Been Discovered?!?

  • 10:42: Which means you don't have to carry the fuel.

2015-10-15: 5 REAL Possibilities for Interstellar Travel

  • 01:50: Traditional rocket fuel.
  • 02:18: The rocket equation tells us that maximum speed is based on exhaust velocity, fuel mass, and spacecraft mass.
  • 02:30: And to do that with any liquid rocket fuel, you'd need a fuel tank larger than the observable universe.
  • 02:48: We just want the fuel with maximum energy density.
  • 03:43: We need to use half of our fuel to slow down at the other end, which unfortunately means we half our speed.
  • 04:57: This is an extremely efficient fuel.
  • 05:37: That's something like 50 times more energy per kilogram of fuel than the best fusion options.
  • 05:42: Low fuel weight means our max speed is limited only by how much antimatter we can make.
  • 07:07: Because we aren't carrying any fuel, maximum speed is only limited by the power and collamation of our laser and the size of our sail.

2015-05-13: 9 NASA Technologies Shaping YOUR Future

  • 01:50: ... oxygen, recycle its waste, and generate its own food in order to keep fuel costs ...
  • 02:45: The ones that feed the rockets fuel and electricity through these fat umbilical cables?

2015-05-06: Should the First Mars Mission Be All Women?

  • 05:35: ... ballpark that you need to work out how much fuel it would take to get that food from Earth orbit to Mars orbit and back, ...
  • 05:55: ... as you add fuel to move your payload, you then need to add fuel to move that fuel and so ...
  • 06:03: ... assume that we wouldn't need any fuel for the descent to Mars, that you'd leave all the food for the return ...
  • 06:17: ... 50 metric tons of food plus food fuel would thus represent around 5% to 7% of the mission mass and 5% to 7% of ...
  • 08:25: ... called "The Mote in God's Eye." The problem is, where do you get the fuel to keep that acceleration ...

2015-04-08: Could You Fart Your Way to the Moon?

  • 00:46: Rockets do not have to ignite or burn fuel in order to achieve propulsion.
  • 00:57: In this picture, you represent the rocket and the ball represents the fuel.
  • 01:10: As it throws fuel in one direction, the fuel pushes back on the rocket to accelerate in the opposite direction.
  • 01:17: So how does it throw the fuel?
  • 02:12: Flatulence is just throwing gas, as opposed to baseballs or rocket fuel, out of your body.
  • 03:00: After a propulsion event, the net momentum of you and your fuel must remain zero.

2015-03-25: Cosmic Microwave Background Explained

  • 06:37: A few of you asked, wouldn't the extra mass of the gyroscopes weigh just as much as extra mass from fuel?

2015-03-18: Can A Starfox Barrel Roll Work In Space?

  • 02:49: That could certainly work, but it means carrying extra fuel for the thrusters to get those big torques over and over.

2015-03-04: Should We Colonize Venus Instead of Mars?

  • 01:23: Shorter trips means less weightlessness and radiation, less food and water to carry, and thus less fuel and lower cost.

2015-02-18: Is It Irrational to Believe in Aliens?

  • 07:19: But think about how much fuel it would take to keep that acceleration going.
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