The Orbital Mechanics Podcast

Spaceflight news— Astra Space obtains launch permits — Three polar launches from Kodiak (apps.fcc.gov) (www.faa.gov) — DARPA launch from Wallops (apps.fcc.gov) — Challenge seeks two launches from different locations with little foreknowledge of payload (darpalaunchchallenge.org — Downselected to only candidate (spectrum.ieee.org)Short & Sweet— Virgin Galactic’s second spaceship passes important milestone. (satellitetoday.com)— Another lunar lander is in the running. (spacenews.com)— Starliner joint investigation announced (spacenews.com)Questions, comments, corrections— twitter.com/chairboy: Gridfins hydraulics — The hydraulic system is closed loop since ~2015 (twitter.com/elonmusk)This week in SF history— 14 Jan 1977: first SCA, N905NA, delivered to Edwards (PDF: nasa.gov) (nationalgeographic.org) (PDF: nasa.gov)— Next week in 2004: no need for TIRS