It may be time to start asking “What now?” again…
In researching my previous post, I talked about the delta-vs planned for Apollo 8. In the Apollo Flight Journal, there’s commentary breaking down the items that were entered for each maneuver. They were all handled by the Apollo Guidance Computer. First off, it floors me that they spent time relaying data by voice which just had to be entered into the computer, when an upload by the ground with a read back from the crew would likely have an improved error rate, and it would still give the crew insight into what was going on so that they weren’t just ‘flying by black box.’ Though given other text in the AFJ, there’s talk of ‘getting your computer back.’
Secondly, I’m impressed that the computer could handle calculations of delta-v in three axes. A simpler way to accomplish the same thing would have been for the astronauts to enter an attitude and a thruster on time. The inertial guidance would be able to determine how much delta-v was applied, which could then update computers on the ground. I’d love to have seen the trades discussed in that development.
The National Academies Institute of Medicine says, there’s no way to do it ethically unless the trip meets our strict criteria. Personally, I’d much rather have the capability built and let anyone who weighs the odds decide for themselves. Good thing these guys weren’t around when we settled the west, migrated from Africa, or even pursued carrier-based aviation… They were all pretty risky endeavors that had questionable immediate payoffs.
That’s the number the B612 Foundation is hinting at leading up to their press event on April 22nd. Interesting approach in releasing the actual number early, building interest to see the animation that they’ll show at the event proper. There’s been discussion of using satellite data to show asteroid entries, but I’ve never seen a report discussing how many they witnessed. I guess any classification of the ground-based explosion sensors was rendered moot by Chelyabinsk, though looking at their website, I guess I’m surprised no one thought of looking into this before.
Recently, I found out Jeff Bell has hit a lot of the same ennui that I have, only he expressed it in an interview on The Space Show. He said many things that I agree with, and I hope he’s wrong about the things I don’t agree with. One item he brought up is that Orion, in its current form of using the European ATV module as its service module, doesn’t have enough delta-v to enter and exit Lunar orbit. He claims that this lack of delta-v is what brought about the Asteroid Rendezvous Mission. So I did a quick Wikipedia based comparison between the Apollo CSM and the Orion Capsule and Service Module:
CSM Delta-V Capability: 2,800m/sec
Orion Delta-V Capability: 1,500m/sec
Delta-V Performed on Apollo 8: 2086m/sec (from the Apollo 8 Flight Journal, and actually reflects the Lunar orbit insertion delta-v (921m/sec) and the contingency burn after the first orbit (1165m/sec))
Therefore, an Orion capsule could not recreate the Apollo 8 mission without enlarging the ATV module.
Small asteroids, mini-moons of Earth.
I like the concept, though I’m not sure how the trades will work out as far as travel time and delta-vs, other than the usual situation of the faster you want to get somewhere, the more propellant you’ll need.
Iridium was one of the darlings of the New Space era of the 1990s. It was going to revolutionize communications by letting people talk around the world with one phone. The program broke new ground in satellite manufacturing, as almost 100 identical satellites were built to fly into space. Unfortunately, while the constellation was built, cellular networks took root around the world, and in combination with their $3 per minute talk cost, the system, putting it kindly, didn’t meet its expectations. An investor swooped in and purchased the whole system for pennies on the dollar, however, and has been operating the constellation with less flair, but enough profit to actually contract for a new generation of satellites. Orbital Sciences just announced that they’re going to start building that new constellation. This is all part of doing more space making space cheaper.
Looks like a fire in one of the downrange RADAR units has shut down the range for a couple flights, including SpaceX’s next station delivery and booster return demonstration. This is something that has to get fixed if we’re going to increase our number of flights. Ranges have settled in to a leisurely flight rate (though for sure it doesn’t feel that way when a couple missions stack up, I’m sure), and some of their infrastructure is decades old. I’m pretty sure it’s something that won’t be released from government control, though, just like air traffic control remains a governmental function.
I’ve rediscovered coding, in some of its new guises like Scratch. People who click here will get a blast from the video game past.