So I took this to the extreme and made this hollowed-out ship, tested in editor:

Blueprint
It regularly farms promethium at 600,000km+, making ~960k science every ~35 minutes. The catch is it requires 24+ levels of stronger explosion, 20+ levels of laser, asteroid productivity 30, and railgun speed 10.
Other features:
- Safe egg belting: the combinators programming of the science area ensure eggs are always belted and consumed at multiples of 10. The science cryo pants are in the range of front rocket turrets so this is necessary to prevent (deadly) friendly fire.
- Unfiltered rocket turrets: they're quite good for defense at high speeds and really far on the shattered planet journey. They do waste some rockets though.
- Carbon-efficient explosives: it uses the sulfer->coal->oil->sulfer loop with biochamber oil processing, fueled by spoilage from eggs and nuclear-powered steam.
- Rocket making layout maximizing beacon reuse, which reduces weight.