As we do from time to time.
Firefly is preparing for the second launch of its Alpha rocket from Vandenberg SFS, California, in late August to early September. Peter Schumacher, interim chief executive of Firefly, said recently that the rocket is ready, and “it’s really pending, at this point, range availability.”
Firefly's last attempt was almost a year ago in September of '21, but failed to reach orbit when one of its first first-stage engines shut down shortly after liftoff. The company is waiting on a launch license from the Federal Aviation Administration, which in turn depends on approval of a new debris model for the rocket. The revised debris model came after the first Alpha rocket exploded in flight when the range activated its flight termination system. Debris from the rocket, made primarily of carbon composite materials, fell outside of the range, including in nearby communities, although no damage was reported.
It's not surprising; the debris models available were based on all-metal rockets and, as they put it, “We have the unfortunate precedent of being the first large composite rocket ever to be terminated,” he said. “So when we did terminate, some of the pieces fell outside where this model predicted.” Oops.
Speaking of oopsies... SpaceX and NASA released that Crew-5, the next crew rotation flight to the Space Station is scheduled for No Earlier Than September 29. But that's not the oopsie.
This mission will fly on a new Falcon 9 first stage. Intriguingly, as part of its explanation for the date, NASA said, "SpaceX is removing and replacing the rocket’s interstage and some onboard instrumentation after the hardware was damaged during transport from SpaceX’s production factory in Hawthorne, California, to the company’s McGregor test facility in Texas for stage testing."
According to one Twitter post, the "damage during transport" occurred when the rocket struck a bridge near Van Horn, Texas.
Tapping or otherwise touching a multi-million dollar rocket into a bridge while strapped on a truck? Oops. At least NASA and SpaceX seem to agree that replacing the interstage will fix it, so it sounds like minor damage.
Remember reading here about the Roman Space Telescope? Named for Nancy Grace Roman as a tribute to the late NASA executive and first Chief Astronomer who was
one of the drivers behind the Hubble Space Telescope program. Although the actual launch is still far out (apparently NET 2026), NASA announced they've chosen the Falcon Heavy to carry the telescope to its orbit. Eric Ralph at Teslarati points out an interesting side note.
Fittingly, the Roman Space Telescope’s basic design is reminiscent of Hubble in many ways, owing to the fact that the mission exists solely because the US National Reconnaissance Office (NRO) chose to donate an unused multi-billion-dollar spy satellite – a satellite that was effectively a secret Earth-facing version of Hubble.
Falcon Heavy is in a unique place in the American space fleet. It's the heaviest lift vehicle in the fleet at the moment and so it has attracted some big missions, like the Europa Clipper. Unfortunately, that comes at a price. As Ralph points out:
... the major missions that are increasingly being entrusted to Falcon Heavy are far more likely to run into significant spacecraft-side delays. At one point in late 2021, for example, SpaceX had five Falcon Heavy launches tentatively planned in 2022 – all but one of which had already been delayed several months to a year or more. Seven months into 2022, not one of those missions has launched and it’s looking increasingly likely that Falcon Heavy will be lucky to fly at all this year.
That's too bad about Falcon Heavy. A certain amount of "continuity of operation" is always better to have than a period of enforced idleness. I hope that it doesn't hurt.
ReplyDeleteSo, what could a "secret Earth-facing version of Hubble" see? Our license plates on a slant? Read our smart phone screens? Soon will they demand we put license plates on our car roof?
ReplyDeleteThe number I’ve seen bandied about is about 4” for Corona’s, mainly due to atmospheric conditions. Enough to see a license plate, but not good enough to read it.
DeleteI didn't answer the first one since I have no knowledge of what they can really see, but I do have some limited insight on that 4" resolution thing. Think of that as one pixel. One block. Like you say, if you were looking at license plate with 4" pixels you might be able to decide one area was probably the characters and another area the background, but you'd need far more resolution than 4" to read the numbers.
DeleteAdd in that these pictures are taken while the satellite is moving and not necessarily tracking the thing on the ground and it gets more complicated.
I could be horribly underestimating how good the technology is, but it seems far better at identifying and tracking military targets the size of tanks, mobile missile launchers and ships than cars and people.
If memory serves I think my reference was “Deep Black” by William Burrow. He concludes that Corona needed that to estimate the diameter of missiles in their silos with hatches opened for arms control treaty purposes to that accuracy.
DeleteBut not, contrary to rumor, the brand on the President’s golf balls.
That said, we are talking 80’s engineering, the fundamentals haven't changed since but optical sensors have improved to near quantum limits, and the computers are fabulously better.
Optical sensors are still limited by physics which says resolution is limited by the aperture. The only way to resolve smaller objects (like the legendary golf ball labels) is with bigger optics. That's why the Webb is bigger than Hubble. Resolution depends also depends on wavelength, so it also needs to be bigger to get better angular separation at far infrared.
DeleteThe advances since the 80s in telescope design have been multiple mirrors, again like Webb, as ways to get bigger optics without some of the awful tradeoffs that single-piece mirrors force on you. It kind of forces the question of whether there are multiple mirror versions of those "downward-looking Hubble" telescopes up there, and they sure don't talk about that kind of detail. I suppose I wouldn't be surprised, though.
I believe the optical sensor density - size of pixels approaching quantum limits - isn't important. The size it needs to be is determined by aperture and f-number, and that's the same physics as the angular resolution. Too fine a pixel size wastes memory.
I saw the other day the Webb's internal storage is a 68 gig Solid State Drive. Yeah, it was designed long ago, and they probably updated it along the way, but that's still tiny by today's standards. OTOH, why put in a relatively risky bigger one if it's not needed for the data they collect?