= Catching Stardust =
=== Natalie Starkey, 2018  532.2 Starkey CedarMill ===
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Mostly popsci.  

Chapter 8 about the ESA [[ https://en.wikipedia.org/wiki/Rosetta_(spacecraft) | Rosetta ]] spaceraft toJupiter-family comet [[ https://en.wikipedia.org/wiki/67P/Churyumov%E2%80%93Gerasimenko | 67P/Churyumov–Gerasimenko ]] is interesting.  Black surface temperature 205 to 230 Kelvin, MIRO microwave imager measured 30 to 160 Kelvin subsurface ice temperatures.  Comet heterogeneous, materials from different parts of the solar nebula.

Meter scale [[ https://en.wikipedia.org/wiki/Philae_(spacecraft)#Mission  | Philae]] lander bounced off intended landing spot at "Agilkia" site, came down in unknown location designated "Abydos".  The bounces mistimed experiments; still, useful results from the Cometary Sampling and Composition (COSAC) and 5 kg mass spectrometer (Ptolemy) instruments.  planneCOSAC sampled the surface, Ptolemy sampled gases 1 meter above, interesting differences.

Comet sheds about a meter every perhelion.  Instruments GIADA and COSIMA measured "compact" and "fluffy" dust particles, the compact particles reprocessed by inner solar system and the fluffy particles predating the solar system.

September 2016, Rosetta controlled descent to surface as comet leaves inner solar system.

=== Instruments ===

 . COSIMA ( Cometary Secondary Ion Mass Analyser )
 . GIADA  ( Grain Impact Analyzer and Dust Accumulator )
 . ROSINA ( Rosetta Orbiter Spectrometer for Ion and Neutral Analysis )
  . ices clathrates, not amorphous formed in outer solar system, high D/H ratio indicates outer solar system.

=== 67P/C-G From Wikipedia ===

 . Period 6.44 y
 . Perhelion 1.24 AU
 . 18.7 km³
 . 9.982e12 kg
 . escape velocity 1 m/s
 . two lobes (4.1 km × 3.3 km × 1.8 km, 2.6 km × 2.3 km × 1.8 
 . 12.4 hour rotation period