Space: The Fragile Frontier

Mark Williamson, AIAA Press, 2006

SpaceFragile

Not sure what to make of this book. Some useful information, and some good concerns, mixed with some seemingly unimportant ones.

• Useful concerns (IMHO)
  • Space Debris
  • Unstable graveyard orbits
  • Protection of Space History Sites
• Marginal concerns
  • Non-Contamination by Earth Bacteria
  • Protection of Alien Bacteria

Why marginal? Through aeons of giant boloid bombardment, the Earth and Mars (for example) have exchanged thousands of tons of surface material. Indeed, life could have begun on a cooler Mars, and bombarded it's way to earth later. If there are lifeforms on Mars, they will either be better adapted, or already quite close to what we bring.

• Not concerns (again, IMHO)
  • Moon mining

Why not worried? The moon is big, and relatively simple. We will mine the moon for simple stuff, mostly mass, and we will do so near transport hubs, because it is easier to dig a deeper hole than a far-away hole.

• Crashing Stuff into the Moon

Why not worried? The moon is big, and relatively simple. The chance of a crashing object destroying something truly unique is small. If we crashed enough stuff to change most of the moon's surface, we would direct it to a few crash zones to make recycling easier.

Page 86, the Altitude of the Graveyard Orbit, is useful, describing the tradeoffs between reserving propellant for transfer to graveyard versus operating life. Note that as technology accelerates, we sometimes obsolete still-functional-and-fueled satellites because we can put a much better one in its place. The IADC recommendation for graveyard altitude is 35786 + 235 + 1000 CR A / m, where CR is the reflectivity and A/m is the sail ratio, m²/ kg. "In October 2005, the FCC ... license applications to include detailed commitments to debris mitigation in their applications.

90, cite: Ramohalli, Kumar, and Jennifer Jackson. "Space debris- An engineering solution with an autonomous space robot." Space safety and rescue 1994 (1996): 253-265., also International Astronautical Federation Paper IAA-94-IAA.6.5.695, Oct. 1994