The BBC News article Hayabusa-2: Japanese probe set to 'bomb' an asteroid says:
The charge is carried on the Small Carry-On Impactor (SCI) device.
This is a 14kg conical container attached to Hayabusa-2 and packed with plastic explosive.
The SCI is due to separate from Hayabusa-2 at 01:56 GMT on Friday at an altitude of 500m above the surface of Ryugu. That will kick off a 40-minute countdown to detonation. When the device explodes, it is expected to punch a 10m-wide hole in the asteroid.
In the meantime, Hayabusa-2 should have manoeuvred itself to hide away on the other side of the asteroid, shielding the spacecraft from any flying debris.
I don't know how much of the 14 kg is the explosive, but the video shows the explosion to at least not be trivial.
Still, I'm wondering if explosives have been used on other bodies beyond Earth orbit. Thus the question Was Hayabusa-2's plastic explosive charge the largest explosive charge to detonate in beyond LEO? Why "beyond LEO"? Starfish Prime.
I suppose answers will have to be revised again in several years, when space-prospectors start blowing things up regularly. which may happen in the the non-too-distant future on the south pole of the Moon.
See also related items:
- How far will Hayabusa-2 back off before the “bomb” goes off?
- Has anything like the Luna 2 “Flag Grenade” been done since?
- What is the deepest we have penetrated a terrestrial body other than Earth?
- Highest velocity impact between a spacecraft and a solar system body? What about for a dedicated impactor (spacecraft component)?
- Didn't the Apollo missions had (seismic) grenades as well?