Josh Hopkins
@spacejosh.bsky.social
Designer of spacecraft and writer/editor in the space industry. History buff, rocket geek, orbits nerd, asteroid enthusiast, airship and aviation fan. Allergy warning: posts may contain puns.
More info here, for Clarke fans. Or comsat fans. bsky.app/profile/spac...
80 years ago, as WWII was ending, a young RAF engineer and science fiction enthusiast named Arthur C. Clarke published a short piece titled “Extra-Terrestrial Relays" in the October 1945 issue of Wireless World. It changed the world.
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December 16, 2025 at 3:45 PM
More info here, for Clarke fans. Or comsat fans. bsky.app/profile/spac...
This year marks the 80th anniversary of his publication of the article describing the communications satellite. I had not realized until recently that he invented the comsat before going to college.
December 16, 2025 at 3:43 PM
This year marks the 80th anniversary of his publication of the article describing the communications satellite. I had not realized until recently that he invented the comsat before going to college.
Thank you for posting these data. I’ve been wondering how effective Ukraine’s kinetic sanctions on refineries have been. The answer seems to be “some, but not as much as they might appear.” Presumably infrastructure gets repaired.
December 13, 2025 at 4:08 PM
Thank you for posting these data. I’ve been wondering how effective Ukraine’s kinetic sanctions on refineries have been. The answer seems to be “some, but not as much as they might appear.” Presumably infrastructure gets repaired.
“Potentially stable” is a delightfully optimistic way of describing a rocket propellant.
Reminds me of someone who wanted to make strained ring ozone as a more energetic oxidizer.
Reminds me of someone who wanted to make strained ring ozone as a more energetic oxidizer.
December 5, 2025 at 4:11 AM
“Potentially stable” is a delightfully optimistic way of describing a rocket propellant.
Reminds me of someone who wanted to make strained ring ozone as a more energetic oxidizer.
Reminds me of someone who wanted to make strained ring ozone as a more energetic oxidizer.
Speaking as a spacecraft engineer, the thing that gets me about Loeb's interpretations is that his alien engineers are insultingly incompetent.
RCS thruster plumes visible from the other side of the solar system, making no difference in the trajectory?!
And 'Oumuamua was a *terrible* solar sail.
RCS thruster plumes visible from the other side of the solar system, making no difference in the trajectory?!
And 'Oumuamua was a *terrible* solar sail.
November 8, 2025 at 7:51 PM
Speaking as a spacecraft engineer, the thing that gets me about Loeb's interpretations is that his alien engineers are insultingly incompetent.
RCS thruster plumes visible from the other side of the solar system, making no difference in the trajectory?!
And 'Oumuamua was a *terrible* solar sail.
RCS thruster plumes visible from the other side of the solar system, making no difference in the trajectory?!
And 'Oumuamua was a *terrible* solar sail.