What if a real 1e38j LASER beam hit an earht like planet?

[His Divine Shadow]

The beam would hit straight on the planet, it's 10 kilometers in diameter.

I mean, would the thermal stress blow it apart deathstar style or would it cleave it in two or would the beam punch through leaving the planet intact?

Just curious.

[Darth Wong]

The beam would hit straight on the planet, it's 10 kilometers in diameter.

I mean, would the thermal stress blow it apart deathstar style or would it cleave it in two or would the beam punch through leaving the planet intact?

Just curious.

I don't think we'd see drilling through the target. Nuclear blasts demonstrate that a sufficiently large energy release ionizes a target volume of matter and creates a volume of matter which is largely opaque to the radiation, hence the laser will probably dump most of its energy into the contact area.

From that point, we would have to expect enormous energetic matter which transfers energy to the rest of the planet through convection and radiation. The result would probably be something like rocket propulsion, with huge masses of matter flying away from the near side of the planet while the rest is heated up and blown apart the other way.

The sheer energy content would probably mean that the entire mass is effortlessly vapourized, and probably largely ionized. It would dissipate and overcome gravity because its particle velocity is so high.

[His Divine Shadow]

Sounds cool

EDIT:
Having half the planet blown away at high speeds like that almost sounds cooler than the flakburst like effect we see from the superlaser.

[Durandal]

I'm pretty sure you'd also have an atmospheric shockwave created when the beam enters the atmosphere. The sheer heat density of the beam would heat the atmosphere around it and basically force it out of the way with probably relativistic velocities.

There's an interesting thought experiment...

[His Divine Shadow]

There's an interesting visual FX moment I think...

Maybe in the next re-remake of the OT they'll change the explosion to loook like what is described here

[Darth Wong]

I'm pretty sure you'd also have an atmospheric shockwave created when the beam enters the atmosphere. The sheer heat density of the beam would heat the atmosphere around it and basically force it out of the way with probably relativistic velocities.

There's an interesting thought experiment...

A shockwave can only propagate at the speed of sound, so in this case, I would think that radiative heating will cascade outwards (radiation heats up shell to enormous temperatures, the shell radiates and heats up a larger shell to enormous temperatures, the second shell radiates ... etc) faster than any shockwave effects.

In a nuclear blast, there are two thermal pulses: the prompt blast and a second thermal pulse which is caused by the shockfront moving outward so quickly that it heats the air in front of it to extreme temperatures. We would see both phenomena here; prompt radiation from matter heated to extreme temperatures by the laser (a pulse which continues for the duration of the beam) and further radiative heating from the shockfront moving outwards at high velocity.

In essence, I would expect relativistic particles moving out from the region of impact, striking other particles in the planet and shock-heating them as they move. Think of extremely penetrative radiation saturating the entire planet from the contact point and heating it that way.

A theoretical physicist would be better at accurately modelling this process, however.

[Singular Quartet]

In essences, really big exploiosn, with massive shockwave killing all life on the planet?

[ArmorPierce]

Looks like it

[ClaysGhost]

Lasers are great. The electric fields set up by one of this power would barely permit electrons to say "bye" before they got ripped away from their parent atoms. Even modern TW-level lasers ionise the target region exposed to the beam. The resulting surface plasma explodes outward, but deeper in the plasma implodes to conserve momentum, producing a shockwave that ionises the rest of the target.