space invaders

A PBS Space Time episode hosted by Gabe Perez-Giz on the nature of spacetime and whether space and time are fundamental. It builds up reference frames and causality in a short, dense format.

Scott Manley explains the thermal balance of spacecraft and how a satellite could be configured to radiate away the heat from datacenter-scale computing in space. His rough numbers suggest it is feasible.

A PBS Space Time episode explaining how space and time swap roles inside a black hole's event horizon. It is part of the channel's black hole series.

Kurzgesagt explains how accumulating space junk could trigger a collision cascade (Kessler syndrome) that makes launches too dangerous and traps humanity on Earth.

Isaac Arthur explores space-based solar power, in which satellites beam energy down via microwaves to rectennas on Earth. He discusses feasibility, profitability and its role in spurring space colonization.

Joe Scott takes a serious look at space sunshades as a climate fix, asking how big they would need to be, what they would cost and whether they would work. He draws on Roger Angel's paper and launch options.

PBS Space Time explains the quantum eraser experiment, in which erasing which-path information appears to reverse causality in a double-slit setup. It discusses what this means for quantum mechanics.

A PBS Space Time episode asking what matter, mass, and energy really are, starting with inertial versus gravitational mass and what mass-energy equivalence means.

PBS Space Time introduces Miguel Alcubierre's warp drive, explaining how spacetime itself could be warped rather than moving a ship through it, and whether it is physically possible.

PBS Space Time explains what happens as you approach and cross a black hole's event horizon, using Penrose diagrams and light cones as the tool for understanding spacetime there.

PBS Space Time explains the Higgs field and how the Higgs mechanism gives particles mass within quantum field theory. It is a ten-minute overview for a lay audience.

Scott Manley examines why SpaceX, Google and others are looking at orbital data centers. He walks through the economics, heat rejection and solar power arguments, with links to the Lumen/Starcloud and Google Suncatcher papers.

Curious Droid surveys vertical take-off and landing rockets that predate SpaceX and Blue Origin, including the McDonnell Douglas DC-X of the 1990s. It shows that propulsive landing has about 60 years of history.

Everyday Astronaut explains the basic physics of rocket engines, the main engine cycles and fuel types, then compares SpaceX's methane-fueled full-flow staged combustion Raptor to other engines. It runs nearly 50 minutes with chapter markers.

Real Engineering explains why SpaceX is building Starlink, including the economics of satellite internet. It covers the latency advantage of light in vacuum over fiber for long-distance links.

Kurzgesagt explains the skyhook, a rotating cable with a counterweight that could catapult spacecraft from Earth orbit toward deep space. It covers why it would make space travel cheaper and more efficient.

A PBS Space Time episode introducing de Broglie-Bohm pilot wave theory, an interpretation of quantum mechanics that avoids much of the strangeness of the mainstream views. It is aimed at curious lay viewers.

PBS Space Time examines the interstellar object 'Oumuamua and the popular theories about it, including the light-sail hypothesis. It argues that a natural rock is the likeliest explanation.

PBS Space Time explains the Bohr-Einstein debate over quantum mechanics and how quantum entanglement settled it. It covers the weirdness of measurement and nonlocal correlations.

PBS Space Time explains how spacetime geometry and light cones determine the order of events and what can cause what. It visualizes causality in special relativity.

PBS Space Time surveys five realistic options for interstellar travel, from conventional rocket fuel to antimatter and nuclear pulse propulsion. The options rely only on known physics.

2swap explains how he solved the Klotski sliding-block puzzle by mapping its full state space as a graph and visualizing it. The video includes footage of the Guinness world-record solve and links to an interactive graph.

Real Engineering explains the engineering behind the James Webb Space Telescope, including its folding mirror, sunshield, orbit and cooling systems, and why deployment was so difficult.

Scott Manley looks at SpinLaunch, which aims to throw launch vehicles out of a spinning launcher at hypersonic speed. He covers its recent Mach 1 test of a one-third scale launcher and the engineering problems that remain.

Scott Manley analyzes the idea of putting data centers in orbit, prompted by Lumen Orbit's funding. He examines the claimed advantage of constant solar power against launch cost, cooling and mass.

PBS Space Time argues that the speed of light is better understood as the speed of causality, the universal limit on how fast cause and effect propagate. Light travels at that speed because it is massless, but the limit itself is a property of spacetime.

PBS Space Time explains the proposal to use the Sun's gravity as a giant lens, sending a train of small light-sail spacecraft to the focal point roughly 550 AU out. It covers how such a telescope could image exoplanets in surprising detail and the engineering challenges involved.

A PBS Space Time episode asking whether Venus would be a better colonization target than Mars. It covers Venus's habitable altitudes, floating balloon habitats, and the term surfacism.

PBS Space Time explains the Hubble constant tension, in which two precise, independent methods of measuring the universe's expansion rate disagree. It covers why this calls some standard cosmology into question.

A PBS Space Time episode on how the Higgs mechanism gives particles mass, prompted by Fermilab's heavier-than-expected W boson measurement. It goes beyond the usual pop-science treatment without heavy math.

PBS Space Time explains Stephen Hawking's prediction of Hawking radiation and how black holes can emit radiation and slowly evaporate. It goes beyond the common particle-antiparticle analogy.

A PBS Space Time episode asking what black holes really are and whether events can happen inside them. It covers event horizons, time dilation and common misconceptions about black holes.

Eager Space examines the practicality of putting data centers in orbit, walking through three scenarios with cost calculations and the launch cost reductions that would be required.

A PBS Space Time episode explaining the holographic principle: the idea that our 3+1 dimensional universe may be described by information on a lower-dimensional boundary. It walks through black hole entropy and the AdS/CFT correspondence.

PBS Space Time episode on the black hole information paradox, covering how black holes seem to destroy information, the no-hair conjecture and the proposed role of the event horizon. It is part of a series on black holes.

A PBS Space Time episode explaining the Fermilab Muon g-2 results and why a discrepancy with the Standard Model prediction could point to new physics.

PBS Space Time examines Roger Penrose's idea that consciousness arises from quantum processes in the brain, and reviews new evidence about microtubules. It ends with an estimate of what replicating consciousness would demand.

A PBS Space Time episode asking whether time began at the Big Bang. It explains that the Big Bang is not what most people were taught and what 'start' of the universe really means.

PBS Space Time explores whether time causes gravity, explaining that gravity does not truly warp the flow of time but arises from time gradients. It revisits how gravitational time dilation works in general relativity.

A PBS Space Time episode on fuzzballs, the string-theory proposal for black holes that replaces the singularity with a tangle of strings. It explains why black holes seem to both have to exist and break known physics.