Ad Astra Per Aspera

Biden putting a moon rock in the Oval Office probably signals a stronger commitment to NASA and federal science/R&D investment in general than Trump actually achieved. Replacing the portrait of Andrew Jackson with Ben Franklin doesn't hurt, either.

This doesn't mean that Biden will ultimately deliver on Artemis etc., because the Trump Administration underfunded those efforts so drastically that I don't think any serious commentator still expects astronauts back on Luna by the end of 2024. We're not spending Apollo levels on Artemis—if we're going to start throwing that kind of money around, it ought to be for vaccination and contract-tracing. But more serious White House budget requests for NASA and other research agencies is probably on the table for the next four years.

NASA and SpaceX are aiming for the first crewed Crew Dragon mission again today. The weather forecast, last I heard is still only 50%, and given that it's another instantaneous launch window, there's a very good chance that they'll have to scrub again.

Even if that comes to pass, another dress rehearsal can't hurt. Scheduled liftoff is in a little under an hour. Watch on NASA TV.

Assuming the weather clears up, which is a big assumption, Demonstration Mission 2 launches from Cape Canaveral this afternoon. This will be the first crewed US space launch from American soil since the last shuttle mission in 2011.

To give some perspective, since the last shuttle mission ended, I completed my senior year of high school, took six years to get a four-year degree, was unemployed for a year, and am now halfway through a master's degree. Nobody expected this long of a gap when the shuttle program ended.

Nevertheless, there's some nice continuity between the shuttle and commercial crew eras. Both the SpaceX and Boeing crewed test flight crews include an astronaut from the final shuttle flight. (The Boeing astronaut, Chris Ferguson, has since left NASA and is technically flying as a private-sector crew-member.) Since the crew of STS-135 left a US flag on the station, it's nice to know that either way, the program planners set it up that someone from that same crew would get to capture the flag and bring it back to Terra.

Watch on NASA TV. The launch is scheduled for 4:33 EDT, though be sure to keep an eye on the weather.

NASA has announced the finalists for missions 15 and 16 of the Discovery Program. The four finalists will receive a total of $12M to complete their conceptual design studies on the next nine months, after which NASA will choose two candidates to develop into actual missions.

This process is enormously frustrating, because all the finalists and semi-finalists are/were enormously exciting mission concepts. The fours finalists are DAVINCI+ (a Venus atmosphere probe and orbiter), Io Volcano Observer (a multiple-flyby mission to Jupiter's moon Io), TRIDENT (a single-flyby mission to Neptune's moon Triton), and VERITAS (a Venus geology orbiter).

Based on the brief descriptions and without looking deeply into the technical details of the proposals, I lean a bit towards TRIDENT and IVO. TRIDENT, in particular, is planning to use a series of flyby maneuvers to reach Neptune in a reasonable timeframe, which won't be available in future Discovery slots. IVO isn't exactly as urgent, but would still take quite some time to reach the Jovian system. I don't see giant leaps and bounds in interplanetary flight times coming up (unless my thesis work goes where I hope it does), so the wait calculation suggests we launch sooner rather than later.

Venus, meanwhile, is one of the easiest planetary targets in the Solar System, with launch windows every nineteen months. Delaying a Venus mission isn't as impactful as delaying other sorts of missions. That said, Venus has been underserved as a destination of unmanned probes in recent decades, partially due to the fact that reaching Venus isn't really all that impressive of an achievement, and because it doesn't produce pretty pictures which keep the public excited about paying for expensive exploration missions. Europe and Japan still consider it a valid target, but that doesn't mean NASA should neglect it, either, especially since we're probably the only country right now which could pull off an atmosphere probe like DAVINCI+ is proposing.

It's not my decision, of course, but it'll be very interesting to see which missions NASA opts to develop.

Exactly fifty years ago, the first two men were walking on the lunar surface.

It's been hard to wrap my head around. On my real-name blog, I said that the best way I can think of it is that, when I was born, the Apollo missions were as far in the past as my birth is today. Even so, that's difficult to imagine.

Neil Armstrong always considered the LM touchdown more important than his setting foot on the surface. It's a typical engineer's answer, and of course completely correct. Still, the image of human beings walking around up there truly shook the world. It's been too long, I think, since we've had such a positive world-shaking moment. I don't think space exploration is the only way to do that, but it has a powerful capacity to break through our manufactured normalcy fields and let us see ourselves clearly: as ingenious apes who, against all odds, managed to understand reality, conquer our planet, and turn our gaze outward.

I think the world would be a lot better if all of us could see ourselves that way more often. Hopefully, we'll get a lot more of those moments in the next fifty years of human spaceflight. I'll certainly be trying to make that possible.

One of the interesting things about reading technical books written by multiple authors over subsequent editions (and/or featuring chapters contributed by other authors) is seeing the different ways that people in different subdisciplines approach matters. On the whole, it's not a particularly pleasant experience, because one field will have optimized their approach, and then writers in a different field will try to simplify or restate things in a less-efficient or less-clear matter.

For a concrete example, I'm reading Rocket Propulsion Elements right now, which is considered one of the seminal texts on chemical rockets. I had run into this phenomena before, but propulsion engineers have some truly mystifying ideas about astrodynamics. The "Flight Performance" chapter uses absolutely butchered equations for two-body motion, and in English units of all things! The standard versions that show up in Orbital Mechanics materials are more intuitive, computationally easier, and generally use kilometers instead of feet.

Meanwhile, the chapter on electric propulsion introduces a whole new set of performance parameters. I think these parameters make sense for ion engines and the like, but are less helpful for impulsive transfers. This example is less frustrating and more interesting, because it highlights the ways that chemical and electric rocket engineers measure the efficacy of their solutions. I think the same parameters would apply to both, but since the chapter doesn't really explain said parameters very well, it's not really clear.

One of the long-term goals of my own technical writing is trying to state explicitly the meaning and relationships between different variables and parameters, as well as unifying the equations, notation, and methods to the greatest possible extent.

SpaceX: Falcon Heavy launches with Arabsat 6a, recovering all three of the launch vehicle's cores and the payload fairing. At this point, Falcon Heavy really does appear to be fully operational. Two more launches are tentatively planned this year.

NASA: Two cubesats demonstrated the viability of optical data links between orbiting spacecraft by shining the laser on one satellite towards an infrared detector on the other. Neither instrument was designed for this purpose, but still managed to pick up the signal over a 2400 km distance.

SpaceIL: The privately-operated Beresheet lander failed in its attempt to land on the Lunar surface. It would appear that a combination of propulsion and telecommunications issues during the final descent compounded to result in an impact at about a kilometer per second, which is...non-trivial. Beresheet was nevertheless a very impressive first deep space flight.

ESO: If by some chance you managed to miss this story, astronomers used a network of multiple observatories on four continents to image the supermassive black hole at the galactic core of M87:

ESA: The European Space Agency will use left-over hardware from the Dawn mission for the main imagers on the Hera mission to asteroid Didymos, projected to launch in 2023. Hera will be targeting the same body as NASA's Double Asteroid Redirection Test (DART), representing the first asteroidial science collaboration.

NASA: Unexpected particle plumes erupting from Bennu and higher levels of surface debris are forcing ground controllers to modify mission plans for OSIRIS-REx. While mission planners do not believe the particles represent a serious risk to the spacecraft, the preponderance of boulders is forcing them to rethink the planned sample collection maneuver.

AIAA: Collins Aerospace and Sierra Nevada Corporation are competing to develop next-generation in-space waste-disposal systems. Most astronaut trash is currently returned to Terra in uncontrolled spacecraft; longer-term missions will need better ways to deal with the refuse of human habitation.

ESA: The X-ray Multi-Mirror Newton space telescope discovers two plumes of x-ray emitting material extending from the galactic core, providing an anticipated link between known gas clouds extending away from the galactic plane and the supermassive black hole at its center.

Northwestern: Ground-based simulations indicate that astronauts would probably see significant performance deterioration in the cramped environment of an interplanetary spacecraft. Testing different analog habitats allows us to test existing volume requirement models.

CSA: Canada becomes NASA's first international partner on the Deep Space Lunar Orbital Platform-Gateway, pledging to contribute a robotic manipulator arm for the proposed space station. Initial press releases indicate that it will indeed be known as Canadarm 3.

JPL: Laboratory experiments aiming to replicate the environments of the early ocean depths successfully created amino acids and other organic molecules, demonstrating another path for synthesizing the biochemical building-blocks of life.

ESA: Instruments aboard Mars Express and the Mars Reconnaissance Orbiter provide evidence that ancient Martian groundwater bodies were interconnected, similar to Terra's hydrosphere.

NASA: The SpaceX Crew Dragon vehicle successfully launched to orbit and docked with the International Space Station this weekend. This is a major milestone towards Commercial Crew operations and represents the first time a spacecraft designed for humans launched from the United States since 2011.

This might be an unpopular opinion, but I think that "Earth", "Sun", and "Moon" are kinda silly names for the natural bodies in the Solar System.

"Earth" I can live with, but "Moon"? That's ridiculous, there's hundreds of moons. Unless you're pointing it out in the sky, call ours Luna.

Similarly, the Sun is okay when we're talking about our Solar System or the star we can see in the daytime, but if other stars qua celestial bodies are part of the conversation we should say Sol.

It will be my official policy on this account to use "Terra", "Luna", and "Sol" whenever appropriate.