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1355 points LorenDB | 4 comments | | HN request time: 0.682s | source
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robszumski ◴[] No.44300646[source]
For reference, Rocket Lab's Electron has a wet mass of 13,000 kg. This rocket is much smaller at 1,312 kg wet mass.
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delichon ◴[] No.44301143[source]

  Falcon 9           433k kg  
  Atlas V            547k kg
  Starship         1,200k kg
  Starship Booster 3,600k kg
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Certhas ◴[] No.44301330[source]
k kg is a funny unit... Much more readable than Mg of course. Tonnes would also work...
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1. littlestymaar ◴[] No.44301750[source]
“Mg” wouldn't even be valid since the SI unit is the kilogram. But yeah, using tons is the sensible choice.
replies(2): >>44302031 #>>44302329 #
2. Ekaros ◴[] No.44302031[source]
As valid as milligram, microgram or nanogram. All widely used.
3. Certhas ◴[] No.44302329[source]
Wikipedia would beg to differ:

https://en.wikipedia.org/wiki/Orders_of_magnitude_(mass)

The table at right is based on the kilogram (kg), the base unit of mass in the International System of Units (SI). The kilogram is the only standard unit to include an SI prefix (kilo-) as part of its name. The gram (10−3 kg) is an SI derived unit of mass. However, the names of all SI mass units are based on gram, rather than on kilogram; thus 103 kg is a megagram (106 g), not a kilokilogram.

The tonne (t) is an SI-compatible unit of mass equal to a megagram (Mg), or 10^3 kg. The unit is in common use for masses above about 10^3 kg and is often used with SI prefixes. For example, a gigagram (Gg) or 10^9 g is 10^3 tonnes, commonly called a kilotonne.

One context where I have seen this used is carbon stocks, e.g. petagram of carbon (PgC):

https://www.pmel.noaa.gov/co2/story/Carbon+Cycle

Of course Gigatonne of Co2 is also found very frequently.

replies(1): >>44302756 #
4. littlestymaar ◴[] No.44302756[source]
TIL, thanks.