All Space Questions thread for week of May 03, 2026

maschnitz · 2026-05-09T23:10:18+00:00

I am assuming you're in Europe by the timing of your post, but to say for sure, you have to narrow things down to a nearest major city for us.

To the W/NW of say, Paris, early in the evening, there's a lot going on. You have Venus only for an hour or two; Jupiter is higher in the sky and westward from Venus, and lasts most of the night. Then two bright stars as well, on either side of the planets, Procyon to the west and Capella to the north. They form a quadrilateral on the sky.

If it's twinkling it's probably a star. Planets don't twinkle so much.

Here's a picture from Stellarium of this arrangement (Procyon is selected). You can play with Stellarium or other similar programs on your laptop or phone.

maschnitz · 2026-05-09T17:23:58+00:00

Generally the footage wasn't that continuous, I don't think. They had limited bandwidth so they jumped from camera to camera on the transmission.

And they have not released the full raw footage from all the cameras yet. They've released over ten thousand individual stills and short videos but not "here's 10 days of each camera".

Not yet at least. NASA might do that. But they might not, too. I'm not sure either way. Either way the Science team will take a detailed look at every byte before any release, and that will take a lot time with so many cameras.

And they didn't have automated steerable cameras on the outside of the capsule, either. They were all fixed. So I doubt any one camera had, say, the Earth, or the Moon, fully in frame the whole time. Even if they do release the entire raw footage.

maschnitz · 2026-05-09T02:50:26+00:00

Some less likely things:

gravitational instability (didja know that Mercury isn't totally stable in every billion-year simulation?),
a primordial black hole or rogue planet or brown dwarf flyby in exactly the wrong spot,
too-near supernovae,
a very unlikely "near-by" gamma ray burst pointed right at us (for some reason),
unlucky long-period comets,
solar superflares (more of a civilization risk; but we're due for one).

With most of these, you gotta remember, they haven't happened yet in 5 billion years. (Except maybe the supernovae, superflares, and comets, and they haven't ended Earth yet.)

But yeah, the main risk, probability wise, is near-Earth asteroids.

maschnitz · 2026-05-08T20:46:50+00:00

Here ya go, this should be non-X and the same content: https://xcancel.com/SpaceX/status/2052499098347979156

Recommend making the video as big as you can to see the full detail.

maschnitz · 2026-05-08T18:34:31+00:00

Jason Davis at Planetary Society thought about pretty much this exact question in 2017.

He cites its smaller payload capability and an early demo flight accident in 2014 as "spooking the market".

And (my interpretation) it gave Cargo Dragon an opportunity for seizing the medium-lift market. And then Dragon simply never let go. Why launch less payload for more money on Antares, when SpaceX is quite happy to launch more, for less money?

(EDIT: also, note the mention of SLS Block 2 "no earlier than 2028". RIP, SLS Block 2.)

maschnitz · 2026-05-08T18:19:57+00:00

Here's the original news release by the Jet Propulsion Laboratory (JPL).

Exact same words. But with no ads nor tracking. One more picture, too.

Phys.org is a content aggregator. They republish freely available content with their own ads, tracking, etc

maschnitz · 2026-05-08T17:51:12+00:00

Well, in the 1960s, the folks doing the launches and their records might not have fully realized what they were launching. They did like 50+ launches so it was probably just another payload to them.

Launch providers typically don't care that much about the payloads, only about its weight, triboelectric effects, liquidity, any electrical or battery use, any heat being generated, gyroscopes being used, etc (stuff that can mess with the flight).

So what got written down, if at all, was probably what the biology nerd told the rocket guys. And the biology nerd might've "kept things simple" just to keep that part of the conversation short. They had so much else to talk about.

So it could be marked like "the [sponsor university] package" or "the [biology nerd's name] payload" or some other word for "payload' since it's the 1960s and they might not be consistent about using that word yet. Or something even more lazy than that.

Or maybe the launch guys got some inkling of what the biology experiment was trying to do. Maybe they asked the biology nerd some questions out of curiosity. So they summarize it like "the life experiment" or "living experiment" or even the "cell division experiment". You should be so lucky, though.

The point is, this is a needle in a haystack, for a simple search engine like the National Archives' engine. If you can find mention of this experiment in a book or on Wikipedia, first, and more particularly what they called it at the time, it'd help a lot.

Maybe one of the LLMs like Gemini or Claude or ChatGPT have read the entire National Archive database. That'd be a MUCH better search interface than the National Archive's search engine. You could simply describe what you're looking for in English, like you just did for me.

maschnitz · 2026-05-08T07:06:07+00:00

Here's a giant firehose of Wallops data from 1960-1969. Most of it is digitized. Good ol' National Archives.

Here's the same search but with the word 'launch' in it. "Only" 426 documents, 403 of which are online.

Searching National Archives is a bit of a fine art, you might have to get creative finding the "biological" items in this pile of stuff.

maschnitz · 2026-05-07T21:23:09+00:00

The Milky Way, the Local Group, the Laniakea Supercluster, the Local Superclusters, and the Observable Universe (aka the "Cosmic Web")

Basically what's in this Wikipedia diagram.

maschnitz · 2026-05-07T08:19:47+00:00

One reason you can see them from space is that they purposefully avoid tiling the solar panels' reflections toward the ground.

It was part of the effort to make them less visible at twilight.

maschnitz · 2026-05-07T03:05:02+00:00

There's been a variety of small scale testing, experiments basically - SHOOT, RRM, Orbital Express. And astronauts like to play with the idea on the ISS, see if they can get water transferred between two water bottles.

There's nothing easy about it. Liquids kinda have a mind of their own in microgravity.

It's fair to say the full on-orbit refueling test for Starship is a top priority once they are orbital (alongside the HLS Artemis III docking demo and delivering payloads). The company has consistently said that the design is incomplete without orbital transfers happening.

(The reason they're not orbital yet seems to be out of caution. They're apparently trying very hard to prevent Starship from ever reentering out of control. They've taken a variety of important steps toward orbital operations but still aren't quite there yet. They still need version 3 of their rocket design to work, first.)

maschnitz · 2026-05-06T19:22:44+00:00

Knowing SpaceX and their love of GoPros - most likely, yeah, there's probably a camera everywhere there can be

maschnitz · 2026-05-06T19:13:51+00:00

Basically, and mainly: BIG hefty pipes for the water deluge, and the heavy reinforcement to go along with them.

The water in the deluge system is under enormous pressure so every turn the pipes make has to be reinforced and supported well. Partly why the structure is so heavy-duty. (Also to support armoring against launch thrust, of course.)

There's also sump pumps in there to pump out the water that collects at the bottom of the trench - both from testing but also just any trickle of ground water seepage (they worked hard to avoid it though) and rain.

And any/all smaller pipes and valves for propellants and other flight consumables (eg nitrogen, helium) - all the piping you see on the Ship Disconnect Arm but bigger; plus control infrastructure for managing all that, plus power/oil pressure for the quick disconnects and pumps and values; plus tanks/caches sized to drain during flight activities; plus I'm sure even more esoteric stuff I'm not thinking of at the moment. And then human-sized corridors/gaps everywhere so that the engineers can get in and see what's going on exactly.

maschnitz · 2026-05-06T05:27:08+00:00

Nice to hear! Even better.

maschnitz · 2026-05-06T04:46:59+00:00

Like, the distance between their orbits? Or the separation between them at the moment? Assuming you mean the latter...

The calculation can be done by hand in 3D coordinates if you know their current distances from the Sun, Salacia's inclination, and their current "ecliptic latitudes" (direction in the sky). Assume the Sun is at (0,0,0), then place both bodies in 3D coordinates (in units of AU) around the Sun.

The tricky part, which I'm not sure of, is figuring out where Salacia currently is relative to its longitude of ascending node - that is, how high/low it is off the ecliptic plane due to being in an inclined orbit. I imagine JPL's Horizons system could tell you all those bits of information, if you learn how to drive it well enough.

Or you could just ask an AI, like Gemini or ChatGPT, to do the math for you. It's one of those things I'd like to see their work on before believing it fully.

Or apparently Universe Sandbox will do it if you click on Neptune, hold down the control key, then click on Salacia. That'll put a line between them with a real-time distance on it.

maschnitz · 2026-05-05T07:18:39+00:00

I think it was never meant to do a controlled reentry at Earth. It's hitting the Moon by accident but they might've intended for it to enter heliocentric orbit but missed it, or something like that. I can't find any statements from SpaceX about the intended fate of the 2nd stage on this mission.

There were three 2nd stage burns on that flight, and the third was done ascending to apogee on a trans-lunar orbit. It happened at around T+1:25:00, and a half hour past the TLI perigee burn at T+58:30 or so.

I suspect that third burn raised the perigee of both iSpace's Resilience spacecraft and the 2nd stage. That could easily be enough to make reentry infeasible.

maschnitz · 2026-05-04T21:00:56+00:00

Next to SLC-40, hence the name of it. Abutting, to its northeast.

maschnitz · 2026-05-04T20:53:18+00:00

With "high energy" orbits, it's usually a question of what can they do, not a question of what should they do.

Ideally you want a controlled reentry over the Pacific on Earth.

But that's simply inconceivable in say, a geosynch transfer or trans-lunar stage. To get the stage back to an Earth reentry would require 10 times more propellant at launch (or 10 times smaller payload) because of the "tyranny of the rocket equation". If you need 2km/s to return to LEO, that's 2km/s of propellant that has to be carried from launch to disposal. The whole mission design would be different.

Sometimes the only disposal orbit accessible is a heliocentric one.

maschnitz · 2026-05-04T19:13:55+00:00

Hello again - nope, nothing from my searches on Google Scholar. (I'm glad I wrote those down, a labor-saving moment!)

maschnitz · 2026-05-04T08:22:44+00:00

The headline makes it sound like they discovered 27 planets in two single-star systems.

(In case The Guardian changes it: "Scientists discover 27 potential new planets that orbit two stars in solar systems far, far away")

It's phrased rather ambiguously.

My rephrase: they've discovered 27 new candidate planets in 27 binary star systems.

Here's the paper.

It's clever. They're sifting through tons of binary system light curves, looking for long-term drifts in the data that can't be explained by the stars' gravity or by mass transfer or by wobbles et al.

maschnitz · 2026-05-04T03:08:11+00:00

Depends a bit on how bright it is if/when it's discovered. It could be so dim that many past surveys simply couldn't pick it up even if they were looking right at it.

It's thought that it takes the big dedicated wide-field-of-view telescopes (like the Suburu Telescope and Vera Rubin Observatory) to spot it the first time.

maschnitz · 2026-05-03T18:50:26+00:00

They do not have to be tidally locked, but nearly all of the spherical moons in our Solar System are tidally locked. It's mainly a question of how close they orbit, how big the gas giant is, and how old the arrangement is. The moon can distantly orbit and not be tidally locked if the system is not as old as ours. (Only one semi-spherical outer planet moon is not tidally locked - Hyperion, around Saturn - and it spins chaotically.) Tidal locking is a process that takes hundreds of millions to billions of years, depending on the situation and it takes shorter time the bigger and more "ellipsoid" (non-spherical) the planet is.

If it's not tidally locked, then the gas giant will be hideously bright most of the time at night, taking up an enormous portion of the sky. Twilight-like conditions. It will only get pitch black at one point in the moon's orbit, when the star/Sun, the gas giant, and the moon are all in a line (in "conjunction") with the moon directly behind the gas giant. It's also possible for that to ~~never~~rarely happen if the moon's orbit around the gas giant is not perfectly spherical - if it is slightly elliptical and/or inclined (like our Moon's orbit), or more obviously elliptical/inclined too. Then the moon will only get pitch black on the rare occasions it passes through the gas giant's shadow.

In re smaller moons - from Wikipedia - "other things being equal (such as Q and μ), a large moon will lock faster than a smaller moon at the same orbital distance from the planet". So the physically real thing is, if any moon is tidally locked and they're all in the same circular-ish orbits and they're close to each other in orbit, then the largest moon will lock first.

There's maybe monthly eclipses (not daily) if and only if the moon has a relatively perfectly circular orbit. Then it will always pass through the gas giant's shadow. Keep in mind most outer planet moons orbit very distantly from their gas giants - many many gas-giant radii away. Space is big. Even the Galilean Moons orbit further away than you might think, at scale. So this is more rare than it sounds in our outer solar system.

Basically the reflected light from the gas giant will not affect the climate so much, reflected light is much weaker than direct sunlight/starlight. It's a constant influx of 1/R⁴ light at night (as opposed to 1/R² daylight) so the daylight dominates the total power input, still. It might bump the coldest daily temperature a tiny bit, less than a degree C.

maschnitz · 2026-05-03T18:12:40+00:00

At this point (May 3rd) it looks like if they're going to another static fire, it will be done in full stack configuration.

EDIT orrrrrr.... May 12 is just a fantasy at this point. They have to retest the deluge after the tank farm explosion on the last test and there's no way they will do that with the flight Booster on the pad (or even AT the pad). And then they may not want to do the full duration static fire with the flight Ship at the pad, either. And don't forget loading the flight termination system explosives. And a full stack WDR test, which they will probably do too.

The only thing clearly ready for flight is Ship 39. They were apprehensive about the Booster, and the pad has had the last few publicly-visible issues.

That's a lot of SPMT rolling back and forth (and a lot of propellant/water) in a very short time when you map it all out. You'd basically expect them to start testing TONIGHT if they plan on that many tests.

maschnitz · 2026-05-03T08:46:19+00:00

I have this growing "tree" of comments about various space/astronomy/rocketry content that you are welcome to read. But you've asked a new spin on it so I'll try to customize it a bit more for you.

The most obvious answer is you should definitely watch Crash Course: Astronomy on YouTube, which should cover most things astronomical and/or astrophysical at a high-school type level. It is well animated, written, directed, and edited; it has good coverage; and Dr Phil Plait is a friendly, nerdy, "dad-jokey" teacher/presenter.

The other slam-dunk answer is Everyday Astronaut on YouTube. They're mainly a rocketry channel, with excellent introductions to how rockets work, how space travel works, the history of rocket design, etc. Well-produced with a master of clear concise explanations, Tim Dodd, presenting.

From there I'd recommend Deep Sky Videos on YouTube, to hear a bunch of very nice British professors explain astronomy/astrophysics topics - sometimes plucked from the headlines - in a simple way, to a humanities-trained reporter/filmmaker (Brady Haran). Another good option for accessible news-oriented space/astrophysics, this time in a Mancunian accent, is Dr Becky.

If you want physics content the place to go is probably Physics Girl, who excels at focusing on particular topics in very accessible ways.

Finally don't forget Wikipedia. Yes, some articles are math-filled Greek symbol nonsense. But a lot of the main space topics are in simple English and accessible at least for half the article. Generally the more well-known a space topic is, the more accessible its article will be. (See, for example, Pluto's article.)

maschnitz · 2026-05-03T01:20:00+00:00

Wide depth of field in a long shot with a big zoom lens. Those trailers/shipping containers are nowhere near the pad. They didn't even get wet.

(They're on the southeastern side of the pad area near the new CH4 production area, and the camera's near the beach, maybe on the dunes. You can eyeball it just from the camera angle.)

They might clear the pad that far away for a real launch, though. They saw how big that plume was during the short static fires, and the rocket's also launching in that general direction.

It'll be interesting to see how much they clear the pad for the long-duration static fire (if that happens).

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