Recent content by mfb

I can reproduce the problem. The verification works for me but then I'm not logged in on the contact pact, and can't login either. @Greg Bernhardt. https://www.physicsforums.com/misc/contact You can still send a mail manually.

Starliner passed its flight readiness review for the crewed flight test, scheduled for May 7. It is expected to stay at the ISS for about one week. If successful, it will become the second privately developed spacecraft to launch astronauts to orbit, four years after Dragon. It will be the first...

The energy is not generated, it is just converted from one type to another. The mass changes. What is unclear? As an example, a hydrogen atom has a slightly smaller mass than the sum of a proton mass plus an electron mass.

If there is a way to make a diode to isolate inputs then it should be possible to make logic gates out of it. Getting the timing of all signals right will be a challenge as we rely on signals that always move. Make time steps of half the refractory period. Define an on ->off sequence as 1 and...

Assuming proton decay is possible, the energy released is too large to stabilize them in any way. Neutrons can decay via equivalent methods then, their environment doesn't matter either.

Only if they abuse the monopoly. SpaceX saves its customers billions.

2023 launch statistics and analysis Mass to orbit by rocket: SpaceX launched 5 times more mass than the rest of the world combined.

Not in any significant amount. It's possible all 4 effects exist, but they are all negligible. The average ocean depth is ~4000 meters. Long-term sea level rise might be a few meters. So maybe we change the slowing rate by 0.1% in either direction for 1000 years or something like that...

A good permanent magnet can achieve that on its surface, but if you want something you can walk into then you need a large superconducting magnet. MRI machines have stronger fields and people are moved into them routinely. So it's both (a) not possible with permanent magnets and (b) safe.

Sleeping giant surprises Gaia scientists A 33 solar mass black hole (Gaia BH3) 1900 light years away. It's not the nearest one, but it's an interesting object - the heaviest stellar-mass black hole known in our galaxy. It's orbited by a star at a distance of 16 AU. So far away that the black...

The chance that Gwynne Shotwell leaves SpaceX to join Boeing is about 0.00000%. Don't know about Pat Shanahan, but more generally: The people that Boeing would need are unlikely to go to Boeing.

Alpha decay of naturally occurring neodymium isotopes Neodymium has two radioactive isotopes in its natural composition, 22.8% Nd-144 and 5.6% Nd-150, but their half lives are so long (over a quadrillion years) that this is completely negligible. So technically it is correct, it just doesn't...

Online That's based on the first four months of Kepler data, it's only looking at Sun-like stars, and only considering "Earth analog" planets. Kepler had no chance to observe three transits for habitable planets around Sun-like stars in that time so there is a huge amount of extrapolation...

Angles can be compared across experiments, physical dimensions cannot. In addition the calorimeter has some non-zero depth, so just plotting x and y would smear out clusters that point away from the interaction point. You could project everything onto a fixed plane, but that's just extra effort...

It's not. Induced fission is not a radioactive decay. Plutonium is only useful in weapons when it is made specifically for that purpose. You can make it unusable for weapons by putting it back into a nuclear reactor where some of it will fission and some of it will capture another neutron.