Monday, April 22, 2024

It's Time to Celebrate Earf Day 2024!

It's time for our annual bacchanalia of the made-up holiday they call Earth Day, my very favorite holiday to make fun of.  Yes, even more than Kwanzaa.

As befitting the environmental movement, my tribute to Earth Day is almost entirely recycled, and is almost entirely useless. Plus, it's late. The only way it could fit the environmental movement better would be if everything I said was factually wrong. Everything here is factually correct. 

I've posted on Earf Day so many times that it's hard not to be repetitive, even if I was trying not to. So nothing this time about Ira Einhorn murdering his girlfriend or the almost completely discredited book, The Population Bomb. No, wait. I just did. Rats! 

The simple truth is that virtually everything about the holiday and the environmental movement is crap. The modern green movement is simply about rich, privileged people wanting to have places to visit that they consider to be unspoiled. They want pretty, natural, wild-looking places to visit on vacations. If that means the people who are living in or near those places have to live lives that range from austere to practically unsurvivable, that's fine. 

Under that picture, it's easy to realize that the greenies care only about themselves and their enjoyments of life. Of course we should all protect the wilderness! It's theirs! That was never as clear to me as it was while reading Apocalypse Never by Michael Shellenberger a couple of years ago. He vividly talks about people in the wilds of Africa who desperately need better ways to grow food, get water and need electricity. Instead they're kept in a life of desperation by the environmentalists.

Probably the worst example is the on that we get beat up about every day: climate change. Notice they don't mention "global warming" any more. It just change. As if the worldwide climate has always been the same. Let's start with that simple observation. They scream that the temperature has gone up since 1850! We're all going to die! Phrased a little differently, the temperature has gone up compared to the coldest period in the last 10,000 years.

That's Indonesia. How about if we reconstruct the temperature half a world away? North Atlantic instead of south Pacific; Greenland instead of Indonesia.

Those match fairly well but 1200 years ago was colder than the little ice age, while not as cold as about 8300 years ago.

Sorry. The temperature has gone up from one of the coldest periods in the last 500 million years. 

The closer you look, the worse the picture is. Borepatch ran a piece a little over a week ago about one of the more insidious things they do: they change the historical records to make the older temperatures look cooler and the newer ones look hotter. That's right; they're lying in all the official documents and have been for as long as this Con has been going on. One of the things that convinced me that skepticism was proper was the Surface Stations Project that Watts Up With That? started back in the '00s. It was a report on the official stations that create the weather record and how large percentages of them weren't sited properly; over 62% were incapable of accuracy better than 2 degrees C. Another 6% couldn't measure within 5 degrees C. They're too close to roads, too close to sources of heat like air conditioner outputs, even airport runways, and more problems. Then there was outright fraud in editing records. 

I'm old enough to remember when the fear was a coming ice age. Anything to scare you into compliance. 

And this isn't even going near things like how bad their models are. They still basically can't handle clouds properly. Virtually none of their predictions ever actually prove to be the case. Instead we get useful idiot celebrities who are too young to understand weather and climate both change (to be charitable). If a 20 or a 40 year old can't remember similar weather, it doesn't mean anything.



Sunday, April 21, 2024

Do You Think This is the Only Place Where This is True?

Well, this being a weekend, the news is pretty empty, and that's a good thing because today has been long day of sit around and then rush. So I thought of something I've meant to rant on. 

This is a meme that has appeared in dozens of places. 

First off, I really don't think that's the way the comic first appeared back in '06 (according to the upper right hand corner). The obvious place to start is that the text on the blackboard is nothing like any other text in the cartoon. It's not that it's not a good cartoon, it's just that it doesn't look like a Bizarro.com. But that's not important. 

The point of the meme is obvious: if big pharma and big medicine cure you, they make a small number of sales. One visit or a dozen? It doesn't matter. If you're not going back for treatment, whether it's doctor visits, drugs, or hospitalizations, they all make more money if you're treated regularly and not cured. To use the analogy that I'm sure lots of people are thinking of: why cure a disease if they can just vaccinate you for it or sell you pills for it for the rest of your life. Better yet, what if they can sell massive quantities to governments and maybe put it in the water supply or something? Guaranted sales for decades to come!

The first time I saw this cartoon, I thought, "and you think that doesn't apply to vitamins, supplements and all the other stuff that's being aimed at you?" If you're good at your research and testing, you may find a certain supplement takes care of some symptom you're having. Without fooling yourself with the placebo effect. Congratulations. Now, do you need to take that pill For The Rest Of Your Life? Did you get the dose right and does it change as you get older? The only thing that can be said in favor of fixing issues with whole foods is that you have to buy food anyway and even expensive food might be cheaper than a lot of those vitamin, mineral and whatnot pills. 



Saturday, April 20, 2024

When Hobbies Converge or What The Heck is Meteor Scatter?

It's no secret that I'm a radio amateur (ham radio operator); I've talked about that hundreds of times over the life of the blog.  There has been a Radio Sunday series and a specific Ham Radio Series. This will go with the ham radio series. 

Something I haven't mentioned as often, but still have several times, is that one of my hobbies as far back as I can recall has been astronomy and telescopes. I haven't been active in that for a while, but there are posts here about that I found by going back and searching the blog for specific words. I've built telescopes, reflectors from grinding the mirror from a plate of glass, and refractors from things like copier lenses. Some background here, although not related to tonight's post. 

As an amateur astronomer, I've gone to places near and far where I could observe a meteor shower that was supposed to be particularly good. People who aren't in to this hobby generally aren't aware that there are regularly recurring meteor showers several times a year. If you follow meteor showers to observe the pretty light streaks the meteors leave, you quickly learn that showers are best in the early morning hours, or between midnight and first light. If the moon is close to full and bright, it can wipe out the best of showers.  The reason for the timing is that as the Earth moves in its orbit, the rotation that brings night and day rolls the planet onto some meteors, so more are seen. The meteors have to be moving faster to catch up with the planet.

Back in the 1950s, hams discovered that the trail created in the upper atmosphere by meteors burning up acted like a radio reflector, as if the ionosphere was enhanced. The effect is most beneficial to VHF stations which typically don't have regular, predictable ionospheric propagation. In the early days, this was done with Morse code, or CW as the hams typically call it (CW for Continuous Wave). Now that we're firmly in the age of computer assisted modulation modes, most people trying to bounce signals off the meteor trails are using a computer assisted mode. The most popular appears to be MSK144 (.pdf alert).

MSK stands for minimum shift keying, a form of continuous-phase frequency-shift keying (FSK) with shift equal to half the baud rate. MSK144 uses message frames of 144 bits and modulation at tone frequencies 1000 and 2000 Hz to transmit channel symbols at keying rate of 2000 baud. The resulting audio waveform can be viewed as a form of offset quadrature phase-shift keying (OQPSK) with individual pulses shaped like the first half-period of a sine wave.

Although there are other modes still used for meteor scatter, this is the dominant mode. 

So how do you operate meteor scatter? Have contacts with people hundreds to perhaps 1500 miles or more by bouncing a signal off a meteor trail?  

This is why the talk of meteor showers. This time of year has an annual shower named after the constellation it appears to radiate from, Lyra (the lyre) and called the Lyrid shower. Meteor showers don't just happen, they ordinarily happen when the Earth goes through the trail left by comet; the Lyrids are the trail of comet called C/1861 G1 (Thatcher). That's right, it's a comet that was first named in 1861, and it's a long period comet with around a 422-year orbit. It's expected to return around 2283. Thatcher is the discoverer. 

The Lyrids are predicted to peak Monday morning. Interestingly, another shower is already starting to build, coming to its peak two weeks later on May 5th. This is called the Eta Aquariids because it appears to radiate from close to the star Eta Aquarii. This shower is dust from the trail of Halley's comet. Halley's comet is another relatively long period comet although at 76 years quite a bit shorter than Thatcher's; its last close approach to the sun or perihelion was in 1986, and its next perihelion will be in 2061. I remember taking my son to the beach to see Halley's comet; he was five. I haven't asked him if he remembers that in years. 

Given the shower to provide the meteors and the software to interface to your radio to modulate and demodulate the data stream, if your antenna is directional, it makes sense to point it toward the radiant because the trails will be denser there. Most people use a 15 second transmit period followed by 15 seconds receive. The protocol is that if you're trying to contact people to your east, you transmit on the minute and half minute marks - or 0 and 30 seconds. Those are referred to as the even intervals, so they give rise to the acronym PETE: Point East Transmit Even. If you're trying to contact people to your west, you transmit on the 15 and 45 second marks. 

You'll get the best reflections where the trails are the densest, so unlike the case with other modes, you don't necessarily point your antenna at the person your contacting. It works best if you're both pointed at the radiant. Remember, the radiant is like everything else in the sky: it raises in the East and sets in the West.  The exact position in the sky of the radiant isn't extremely important, but the astronomy observing-oriented websites help you learn where the radiant is. There's a program aimed at ham use that seems helpful, called Virgo.

It's important to know that while the astronomy websites are concerned with the peak number of meteors visible per hour, and the Lyrids aren't impressive that way, the showers are perfectly usable for radio after first light and well into the morning. The things that make a shower a highlight for visual observation don't mean much to radio use. I've played at this mode only a few times, and copied signals off the meteor trails until 9 to 10 AM. 



Friday, April 19, 2024

Mars Sample Return and Space Bugs

As a followup of sorts to Monday's post on the Mars Sample Return mission and its problems, Space.com reports on an "Astrobiodefense" committee, the Bipartisan Commission on Biodefense, and their concerns about not just the MSR, but any mission and what it could bring back to Earth. They consider the threat that ecologically-hungry Martian microbes might pose to our biosphere.

The Bipartisan Commission on Biodefense is a privately funded entity established in 2014, set up to evaluate the status of U.S. biodefense efforts and issues recommendations to produce meaningful change.

The only names they associate with the commission are former Democratic Congresswoman Donna Shalala and Susan Brooks, a former U.S. Attorney and Republican Congresswoman. Of course, Donna Shalala was Secretary of Health and Human Services during the Clinton Administration. Congresswoman Brooks served parts of Indiana. 

While many debate the possibility of advanced, intelligent life elsewhere, few consider the probability of non-intelligent alien microorganisms. These life forms could exist on other planets or moons, hitchhike on spacecraft, or move through the universe in the asteroids they inhabit. 

They could also be Earth microbes that mutate or evolve in response to the stress of spaceflight, becoming more virulent, resistant, or invasive. Either would seriously threaten the public health, safety, and security of humans, animals, and plants operating in space or living on Earth," they noted.

To be honest, it was something I thought about when the samples from asteroid Bennu were returned to Earth back in September, and then it turned out the sample container wasn't as well sealed as they may have wanted. That meant if there was a bad organism in that partially sealed container, it would have been released before the sample container was opened. 

Perhaps you might remember The Andromeda Strain, a big seller book early in the career of Michael Crichton and a popular movie in the early '70s. It was the first book of his I read, around 9th or 10th grade. The source of the bug that killed off the town was a satellite that was supposed to capture potential bioweapons high in the atmosphere and hit the ground in this town. A long way of saying the idea of something like this happening has been around a while.

Shalala and Brooks state that the U.S. needs to invest in research and development of new technologies and medical countermeasures to detect, diagnose, treat, and prevent diseases in space and on Earth.

Furthermore, there is need to enhance our bio-surveillance and symptom monitoring to track and analyze space-related biological threats in real time.

“We need to strengthen our coordination and collaboration between agencies and partners, both nationally and internationally," they continue, "to share information and resources without compromising the kinds of competition that result in scientific advances and economic gains."

Early in the Andromeda Strain movie ('71), two researchers recover the capsule that brought back a bug that killed off the small town where it came to the ground. Image published at IMDB.

Let's just say the last few years have dramatically altered the general likelihood that people will want to give much power to the the Bipartisan Commission on Biodefense. 



Thursday, April 18, 2024

Reusability Changes Everything - the Next Chapter

In a company news update early this week, Rocket Lab announced that their first booster set to be reused is moving through the final steps of being certified for its flight, although they didn't announce a date.

Rocket Lab USA, Inc. (Nasdaq: RKLB) (“Rocket Lab” or “the Company”) today announced it is returning a previously flown Electron rocket first stage tank into the Electron production line for the first time in preparation for reflying the stage. The step is a significant milestone in Rocket Lab’s development program to make Electron the world’s first reusable small orbital launch vehicle.

If  you've been following Rocket Lab launches, you'll know that they started trying to recover boosters by catching their parachutes with a helicopter, and actually caught one, but stopped trying after a couple of more attempts. They then switched to essentially what SpaceX is doing, letting it splash into the ocean and having a nearby ship recover it. They say the previously recovered boosters have been used to develop a standardized method of refurbishing and qualifying those boosters for flight again. This booster, originally launched in January of this year.

The stage was successfully launched and recovered as part of the ‘Four of a Kind’ mission on 31 January 2024 and has already passed more acceptance tests than any other recovered Electron stage, including:

  • Tank pressurization test – a process that filled the carbon composite tank with inert gas and held it in excess of maximum operating pressure for more than 20x longer than the standard Electron flight duration;
  • Helium leak check – a stringent process that determines there are no leaks in the tank; and
  • Carbon fiber structural testing – including ultrasonic assessment and other non-destructive tests to confirm no delamination of the carbon composite tank fibers.
...

“This is the exciting final piece of the puzzle before Electron goes reusable,” said Rocket Lab founder and CEO Peter Beck. “Our key priority in pushing this stage back into the standard production flow for the first time is to ensure our systems and qualification processes are fit for accepting pre-flown boosters at scale. If this stage successfully passes and is accepted for flight, we’ll consider opportunities for reflying it in the new year.”Rocket Lab has carried out iterative modifications across multiple recovery missions to hone the recovery process ahead of first reflight, including:

  • Ensuring Electron’s carbon composite structure survives the intense heat and forces of atmospheric reentry through innovative coatings, heat shields, and advanced reaction control systems to control the angle of reentry;
  • Refining the parachute system to ensure reliable deployment and smooth deceleration from more than 2,300 meters per second to 10 meters per second;
  • Honing the telemetry and tracking systems so the marine recovery team can locate the stage as soon as it splashes down;
  • Streamlining the process of collecting the stage from the water in less than an hour, then ensuring safe transit back to the Rocket Lab production complex; and
  • Successful launch of a previously flown Rutherford engine.

The booster immediately before recovery back in January. Image credit: Rocket Lab USA

Bear in mind that Rocket Lab's Electron is in an entirely different market than SpaceX's Falcon 9; the Electron isn't rated to one metric ton to Low Earth Orbit while the Falcon 9 is capable of over 22 metric tons to LEO. Rocket Lab is also working toward a heavier lift booster, the Neutron which is being designed from the start for reuse. I'll speculate that the reason reuse matters for Electron is that SpaceX is sucking up a lot of the market for small satellite launches with their ride sharing missions, Transporter and the new Bandwagon that just had its first flight.  They need to watch their costs.



Wednesday, April 17, 2024

JPL Team Says Goodbye to Ingenuity Helicopter on Mars

The mission of Ingenuity, the wildly successful experimental helicopter sent to Mars strapped to the belly of the Perseverance rover, has long been over. It ended in January, when an accident caused the tips of one or more of its rotor blades to be broken off. At the time, it wasn't known that an entire rotor blade was broken off.

The mission has long been over, but Ingenuity is still operating, communicating back to Earth through Perseverance, widely called Percy, as it has all along. Tuesday, April 16 was different. The JPL team convened one last time on Tuesday to oversee a transmission from the little helicopter, the first robotic craft to explore an atmosphere other than Earth's. This transmission, received through the antennas of NASA’s Deep Space Network, marked the final time the mission team would be working together on Ingenuity operations.

The helicopter has a new mission: to serve as a stationary testbed, collecting data that could benefit future explorers of the Red Planet. 

“With apologies to Dylan Thomas, Ingenuity will not be going gently into that good Martian night,” said Josh Anderson, Ingenuity team lead at JPL. “It is almost unbelievable that after over 1,000 Martian days on the surface, 72 flights, and one rough landing, she still has something to give. And thanks to the dedication of this amazing team, not only did Ingenuity overachieve beyond our wildest dreams, but also it may teach us new lessons in the years to come.”

Originally designed as a short-lived technology demonstration mission that would perform up to five experimental test flights over 30 days, the first aircraft on another world operated from the Martian surface for almost three years, flew more than 14 times farther than the distance expected, and logged more than two hours of total flight time.

A final software update had been sent to Percy to relay over to Ingenuity. The transmission they were there to receive was to verify that the software update succeeded and the little helicopter would be able to start its next mission. The data will stay in Ingenuity because the rover is leaving the area where the chopper is sitting, Valinor Hills, as it moves on to explore the western limb of Jezero Crater. Ingenuity's radio system was never designed to communicate back to Earth. 

With the software patch in place, Ingenuity will now wake up daily, activate its flight computers, and test the performance of its solar panel, batteries, and electronic equipment. In addition, the helicopter will take a picture of the surface with its color camera and collect temperature data from sensors placed throughout the rotorcraft. Ingenuity’s engineers and Mars scientists believe such long-term data collection could not only benefit future designers of aircraft and other vehicles for the Red Planet, but also provide a long-term perspective on Martian weather patterns and dust movement.
...
“Whenever humanity revisits Valinor Hills — either with a rover, a new aircraft, or future astronauts — Ingenuity will be waiting with her last gift of data, a final testament to the reason we dare mighty things,” said Ingenuity’s project manager, Teddy Tzanetos of JPL. “Thank you, Ingenuity, for inspiring a small group of people to overcome seemingly insurmountable odds at the frontiers of space.”

How much data? If a critical component on Ingenuity were to fail in the future, or if the helicopter were to lose power because of dust accumulation on its solar panel, causing data collection to stop, whatever information Ingenuity has collected will remain stored on board. The team has calculated Ingenuity’s memory could potentially hold about 20 years’ worth of daily data. What say we have a couple of astronauts go get that data by about 2040? Less than 20 years.

NASA’s Ingenuity Mars Helicopter, right, stands near the apex of a sand ripple in an image taken by Perseverance on Feb. 24, about five weeks after the rotorcraft’s final flight. Part of one of Ingenuity’s rotor blades lies on the surface about 50 feet west of the helicopter (in the third rounded area from the left in the image). Image credit: NASA/JPL-Caltech/LANL/CNES/CNRS

Some of that Martian dust must have come out of the picture. It's bothering my eyes.



Tuesday, April 16, 2024

Boeing's Starliner Capsule Stacked for May Flight

Boeing's CST-100 Starliner Capsule was rolled to the launch pad today, April 16, and stacked on its Atlas V booster for its long-awaited Crewed Flight Test. 

The spacecraft rolled out from Boeing’s Commercial Crew and Cargo Processing Facility at the Kennedy Space Center to Space Launch Complex 41 in the early morning hours April 16. The spacecraft was hoisted into place atop the Atlas 5 rocket in the Vertical Integration Facility building there later in the day.

The rollout is the latest milestone in preparations for the Crew Flight Test (CFT) mission, which will launch no earlier than the evening of May 6. NASA astronauts Butch Wilmore and Suni Williams will be on board, flying Starliner to the International Space Station. They will remain on the station for about eight days before boarding Starliner for a return to Earth, landing in the southwestern United States.

Launch is currently scheduled for May 6 at 10:34PM EDT. Next Spaceflight notes that this will be the first manned launch from a Cape Canaveral SFS launch pad since Apollo 7 in October 1968, and first ever launch of humans from SLC-41. (Need I point out there was no Space Force (as in SFS) in 1968?) All manned launches for the rest of the Apollo program, Skylab, the Shuttle and everybody launched from 1968 through the current crew rotation missions that resumed in 2020 have been from the Kennedy Space Center side.

As we've noted before, if the launch is delayed a day or two, the liftoff time will move earlier by about 23 minutes per day of delay (due to the Space Station's orbit).

The launch is 13 days short of exactly one year since the last flight of a Starliner, Orbital Flight Test 2, or OFT-2, on May 19, 2022.  In terms of performance, OFT-2 was light years ahead of the first flight test, in December of '19. OFT-1 was so embarrassingly bad they were lucky to get the Starliner capsule back. Boeing's Starliner, like SpaceX's Crew Dragon, was bid as a firm, fixed price contract, and the delays due to their OFT-1 failures along with the many delays since then, have cost the company a lot. I've read as much as $1 billion.

At a March 22 briefing, Mark Nappi, vice president and program manager for Starliner at Boeing, said the key purpose of CFT is to see how spacecraft systems perform with a crew on board. “We flew OFT-2, and that was the uncrewed mission for the Starliner vehicle, and it was very successful. Now we introduce humans.”

Most of the flight test objectives, he said, are devoted to answering “does the vehicle perform with the human in the loop as expected?” That includes various environmental systems, control interfaces and the ability of the astronauts to take manual control of the spacecraft if needed.

A successful OFT-2 would allow NASA to certify Starliner for regular crew rotation flights, currently launched by SpaceX and Roscosmos in Russia. The first crew rotation using Starliner isn't likely until 2025 with a very successful test flight. The better the flight, the earlier in '25.

Boeing's CST-100 Starliner rolls out of its processing facility in the predawn hours of April 16. Image Credit: Boeing



Monday, April 15, 2024

The Situation Looks Bad For Mars Sample Return Mission

I hesitate to use the phrase that the Mars Sample Return (MSR) Mission is cancelled because the source doesn't use that exact, heavy word. Instead, it seems that whatever flies won't look like the missions proposed up to now. 

First, some necessary background. 

I've been trying to follow developments on this mission since 2021; that linked article is in May of '21 so one month short of three years ago, and has a rendering of how the mission was conceived of during MSR's planning. Then Perseverance rover and Ingenuity helicopter started wandering and flying around on Mars, changing everyone's concepts of how a sample return mission could work. Which led the artist's concept to change to look like this.

A conceptual sketch from NASA/JPL-CalTech, showing a helicopter, Perseverance, and the ESA Mars lander on the bottom row, and the ESA's Earth Return orbiter, top row left of center, and NASA's Mars Ascent Vehicle top row right.  The upper left corner picture appears to be a gibbous Earth, but Earth couldn't possibly appear that big from Mars. I'll write that off to someone at JPL-CalTech being overly artistic. 

Last September, NASA received a report from an independent review board saying that the Mars Sample Return Mission was unworkable in its current form and wasn't feasible on the schedule and costs they were working under.  They recommended the issues be studied. The studies were disclosed today, April 15th, and the agency said everything but the exact word “cancelled”, ending instead with saying they will seek “out of the box” ideas in a bid to reduce the costs and shorten the schedule for returning samples from Mars.

In an April 15 briefing, agency officials announced they would solicit proposals from NASA centers and from industry on “innovative designs” to reshape its Mars Sample Return (MSR) effort after an internal review confirmed the ballooning costs of the overall program.

That review found that the current program would cost between $8 billion and $11 billion, the same range offered by an independent assessment completed last September. To fit that into the overall planetary science budget without affecting other programs would delay the return of samples from the early 2030s to 2040.

“The bottom line is that $11 billion is too expensive and not returning samples until 2040 is unacceptably too long,” NASA Administrator Bill Nelson said at the briefing.

As we've said before, those samples to be returned (at least some of them) are on Perseverance RFN - Right Now - and the talk is to conduct an $11 billion mission that returns the samples 17 years from now? 

NASA announced starting over in opening a Request For Proposal immediately - April 16 - with the proposals due May 17. After that, NASA will offer 90 day contracts to the proposals they think the most of. They're specifically looking for alternative approaches for the overall MSR architecture or specific elements of it, like the sample retrieval lander or Mars Ascent Vehicle (MAV) rocket that would place the collected samples into orbit.

Bill Nelson added, “I’m expecting to get everybody in high gear and that we have the answers to this by this fall.” 

NASA seems to be trying to walk the fine line between innovative technologies and those that require a lot of development time (and money). 

“What we’re looking for is heritage,” said Nicola Fox, NASA associate administrator for science. “What we’re hoping is that we’ll be able to get back to some more traditional, tried-and-true architectures, things that do not require huge technological leaps.”

One example she gave is technology that enables a smaller, and presumably less expensive, MAV. The studies, she said, will seek proposals that could return an unspecified number of samples, and not necessarily all the roughly 30 samples that the Perseverance rover will have on board when it completes its work.

The Perseverance  rover landed on Mars in February of '21, so it's reasonable to ask how long it can survive. A plan discussed at the meeting today would have Perseverance complete its exploration of terrain outside Jezero Crater and return to the crater floor in 2028. Once there, it would go into a “quiescent state” until the sample retrieval lander arrived. 

NASA officials said at the briefing and town hall that there was no discussion of suspending or even canceling MSR, citing its high ranking in the last two planetary science decadal survey among flagship-class missions. “Returning these samples from Mars is such a huge priority for us. That is why we’re doing all of these things,” Fox said.



Sunday, April 14, 2024

As We Move Further From the Best Part of the Year

Just an idle post about what I've been up to here.

As the weeks go by, we're going toward the worst part of the year, weather-wise, as we get closer to summer. I've been saying for quite a while that we're the opposite of the rest of the US, and the northern hemisphere. Our best time of year to be outside is coming to an end; for most of the rest of you it's just getting started. 

Not that we don't go outside in the summer, it's just not as pleasant as today has been, with a morning low of 52 and afternoon high of 79. In another few months, the morning low will be 79 or more and the high in the mid 90s. To be fair, it's not all idyllically wonderful weather in the winter, either. December and January alternated nice weeks with rainy, windy ones; we've had a nice stretch since around the start of February. It wasn't a particularly cold winter, but I kept seeing the temperatures below the official averages. Nowhere near record lows, just below average.

This is our dry season, and while I probably should have done this before, I've had to do what's basically annual maintenance on our sprinkler system. I don't know if you're familiar with them; I don't even know if I'm familiar them, but I fumble around and somehow the stuff gets working. Almost all of the sprinklers are popup sprinklers that are only visible when they're running, so I need to run the system to find them all and make sure they're spraying properly. There were two sprinklers that were broken and needed to be dug up and replaced, and another handful that the grass had grown runners over, preventing the sprinkler from popping up. 

Like millions of Florida lawns, we have St. Augustine grass which grows around the yard by putting out tough runners. I'm reasonably sure that in the rest of the world, it would be considered crabgrass.  Our St. Augustine is mixed with nine million species of weeds. Some of the weeds put out tough runners, too - the runners are what keep the sprinklers from popping up.

We live in a pretty reasonable county, but there are restrictions on watering our lawns, using fertilizers, weed killers and all because they run off into the Indian River lagoon. We're allowed to water twice a week, with the schedule set by house numbers - except for testing and fixing things like I've been doing. I've set the timer to start watering by the twice a week schedule starting this coming week. 

Because of doing that work every afternoon for a bit over a week, I haven't spent as much BIC (Butt In Chair) time in front of the radio with the things I've been working on. Three weeks ago today, I posted about geomagnetic storm going on. As it turns out, pretty much every day in the last two weeks has been poor propagation here. Propagation has been strange on VHF (6m: 50-54 MHz). I'll hear stations from the southernmost portions of South America: Argentina, Chile, Uruguay, and Paraguay - all of them with my antenna pointed north. Off the back of this beam (supposed to be 25 dB weaker off the back), they'll be almost as strong as local stations. Sometimes even stronger. 

I only recently noticed I made a really egregious mistake in that post. I showed the pad I added not just in the wrong place, but in the worst possible place, before the LNA.  Check out this comparison. 

Why is before the LNA the worst possible place?  Remember the Ham Radio Series post on Noise Figure? Any loss before the first amplifier takes away weak signals that can never be gotten back. Putting a 13 dB pad before an LNA means the noise figure can never be better than 13 dB. Which is horrifically bad for a VHF radio (and barely acceptable at the AM broadcast band).

The pad was always where it shows on the right side, after the LNA, but I brain-farted when I drew the little picture. Oh, BTW, it's currently a 10 dB pad and may stay that value. 

I mentioned the LNA I used was one I found at the Orlando hamfest for $5. It doesn't have as low a noise figure as the one I started with, but works down to below the AM broadcast band. I found a possible replacement that will upgrade this one with a better NF, made by a company called NooElec, that works from 50kHz up to 150 MHz or above the 2 meter band. As a bonus, it's even cheaper than the one I started with (and built from a kit of parts). I haven't hit the shining, candy-like "Buy" button, but still may well do that.



Saturday, April 13, 2024

The Burgeoning Orbital Debris Removal Industry

The topic of orbital debris removal is one of those "gifts that keep on giving" in that it never goes away. Everyone is concerned about it. I'm going to include things like the Mission Extension Vehicles that we first talked about just over four years ago, February of 2020. This wasn't orbital debris in the typical sense: boosters or parts of satellites that are just left in orbit and either reenter within days or a few years to burn up on re-entry. This was a mission to extend the life of an Intelsat communications satellite (IS-901) in Geosynchronous orbit. The concept is clearly the same.

The Intelsat (IS-901) spacecraft was launched in 2001 and was pulled from active service in December 2019 as it ran low on fuel. Operators commanded the satellite to move into a "graveyard orbit" farther out than the unique geostationary space. It is here that MEV-1 linked up with the communications satellite on Tuesday. 

Payload reports that a startup company called Astroscale had reached a major milestone on their ADRAS-J mission to find and characterize a large piece of orbital debris. 

Astroscale has hunted down its targeted space debris and is now within paparazzi distance. 

The debris removal company announced Wednesday that its ADRAS-J mission has successfully executed its debris rendezvous maneuver and is now gearing up for a proximity approach.

Rendez-who: JAXA tasked the Tokyo-based startup with inspecting a second-stage H-2A rocket that has been floating in orbit since 2009. 

To complicate the situation, this second stage isn't equipped with GPS, making the rendezvous and proximity operations (RPO) more dangerous. During the rendezvous, ADRAS-J lifted its orbit several times, but is still "hundreds of kilometers" away from the H-2A second stage.

In this rendering, the ADRAS-J satellite approaches the target H-2A second stage. Image credit: Astroscale.

This mission will not deorbit the target; the ADRAS-J satellite will move in closer to get more pictures, examining the condition of the debris and learning what it will take to handle that target. They expect to complete the mission by the end of May. Ultimately, the company plans to handle orbital debris by latching onto things like this and deorbiting them. They expect to accomplish that on a followup mission - no date given.

The ADRAS-J spacecraft was selected by the Japan Aerospace Exploration Agency for Phase I of its Commercial Removal of Debris Demonstration program. Astroscale Japan is responsible for the design, manufacture, test, launch and operations of ADRAS-J.



Friday, April 12, 2024

A Night to Keep my Eyes on the Skies

Next Spaceflight shows a Starlink launch (Group 6-49) scheduled for Friday evening at 9:40 PM EDT from SLC-40 at Cape Canaveral Space Force Station.  It has been in their schedule for a while. 

What I didn't know until this evening is that this will be the 20th flight of the booster, B1062, one of the fleet leaders after the untimely wreck of B1058 back in December. This will be the first attempt at a 20th flight for any Falcon 9 booster and it'll be worthwhile watching. B1062 has flown 19 times since its first flight in November 2020, and there are currently three other boosters that have flown 19 times.

Remember when they said they hoped to fly 10 times?

When SpaceX debuted the latest version of its Falcon 9 rocket, the Falcon 9 Block 5, officials said the reusable first stage could fly 10 times with minimal refurbishment and perhaps additional flights with a more extensive overhaul. Now, SpaceX is certifying Falcon 9 boosters for 40 flights.

At the risk of being a pedantic a-hole, I think that last sentence should read, "Now, SpaceX is expecting to certify Falcon 9 boosters for 40 flights."

This particular rocket has not undergone any extended maintenance or long-term grounding. It has flown an average of once every two months since debuting three-and-a-half years ago. So the 20-flight milestone SpaceX will achieve Friday night means this rocket has doubled its original design life and, at the same time, has reached the halfway point of its extended service life.

In its career, this booster has launched eight people and 530 spacecraft, mostly Starlinks. The rocket's first two flights launched GPS navigation satellites for the US military, then it launched two commercial human spaceflight missions with Dragon crew capsules. These were the all-private Inspiration4 mission and Axiom Mission 1, the first fully commercial crew flight to the International Space Station.

Booster 1062 launch, April 29, 2022. Also a Starlink launch, noteworthy for crushing their previous record for recycle time between flights.  Image credit: Richard Angle for Teslrati.

It has been a busy month for SpaceX - 12 days into it. Assuming it launches tonight, it will be the sixth Falcon 9 launch in less than eight days. Since last Friday, launches have included three Starlink flights, the first Bandwagon satellite ride sharing launch, and the launch of a US Space Force weather satellite from Vandenberg. Falcon 9 lifts roughly 80% of all the payloads launched around the world every year. 



Thursday, April 11, 2024

Space Force Set to Modernize US Launch Ranges

Although it has been needed for quite some time, it appears that the US Space Force has decided to commit to upgrading the major US launch ranges, according to a report today on SpaceNews.com

After years of kicking the can down the road on modernization, the U.S. Space Force is now embarking on a comprehensive overhaul of the IT infrastructure used at mission control centers at Cape Canaveral Space Force Station in Florida, and Vandenberg Space Force Base in California.

The launch centers are the places where the mission controllers monitor the space mission’s progress and manage meeting the mission’s objectives. As such, communications and information flow are essential to their function.

The launch ranges’ supporting IT architecture is crucial to the success of space missions and meeting the growing demand for access to space, but the technology is in desperate need of an overhaul, said retired U.S. Air Force Col. Chad Davis, former director of the National Reconnaissance Office’s Office of Space Launch.

Davis, now an executive at Stellar Solutions, directed 12 national security space missions on the East and West coasts.

“At Vandenberg, a lot of the infrastructure that’s there was put in place for the Space Shuttle. That’s how old it is,” Davis told SpaceNews. “They’ve been Band-Aiding it through the years but have never really done any significant overhaul.”

Probably the most succinct summary is that both systems were built around single digits of launches per year and they're looking at meeting three digits worth of launches. Not just doubling or tripling but multiplying the "single digits per year" by 30, 50 or perhaps as much as a hundred in the coming years. Maj. Jason Lowry, deputy director of technology and innovation at the Space Systems Command’s Assured Access to Space program office said this was long overdue, as the private sector has pushed into hundreds of launches per year.

“Imagine a future when the U.S. is launching a rocket every day,” Lowry said.

That means moving away from analog stovepipes to a digital environment where data flows seamlessly and experts can be virtually integrated, he added. “Clearly, we’re going to need to digitize and automate a lot of what we do to support that type of launch cadence.”

SpaceX alone is targeting close to 150 launches this year and while a one per year or one every other year launch like last week's Delta IV Heavy are essentially zero impact, Lowry said they're expecting over 100 launches from the cape, “and we’re also projecting a 30% year over year increase in both the Eastern and Western launch range manifests.” United Launch Alliance is targeting a Vulcan Centaur launch every other week starting next year.

Lots more details at the original source. 


A shuttle mission control center photo from late in the program. This isn't an early '80s version, but this is like what they're planning to upgrade. To include the stuff you can't see like data links in and out.



Wednesday, April 10, 2024

Two Small Unrelated Stories

So Why Did the Delta IV Heavy Set Itself on Fire at Every Launch?

Even Tory Bruno, CEO of ULA, referred to the Delta IV as "the most metal of all rockets, setting itself on fire before it goes to space." Setting itself on fire was because of a design choice, but what was it? And why was it?

A shot of a Delta IV Heavy launch in 2014, found with a web search for "delta iv sets itself on fire." Image Credit: United Launch Alliance

The answer is in the engines used on all three core boosters, the massive RS-68 rocket engines, were developed during the 1990s by Rocketdyne, the same company that developed the Space Shuttle's (and now Artemis') RS-25 engines. These expendable engines were designed to be cheaper and more powerful than the reusable RS-25 engines while running on the same fuel mix of liquid hydrogen and liquid oxygen. 

The fireball phenomenon manifests because of design differences between the RS-68 and the Shuttle main engines and because the RS-68 propellant valve is open longer before the oxidizer starts flowing. Essentially, at engine startup, only liquid hydrogen is running through the engine because it is less chemically active than oxygen.

This hydrogen flows out of the engine, and because hydrogen is very light compared to ambient air, it rises up the outside of the rocket. When the liquid oxygen flow begins, the excess hydrogen is ignited into a fireball. This occurs within the last five seconds of the countdown. This design trade was intentional, and the exterior of the rocket is configured to withstand the fireball.

An imposing fireball during the first moments of flight? I remember people talking like they expected the rocket to explode on its own. That fire is a design feature, not a bug.

A Giant of Theoretical Physics Passed Away This Week

On April 8th, British theoretical physicist Peter Ware Higgs passed away at the age of 94. It was three months short of 12 years ago, on July 4, 2012, when Higgs achieved the practical immortality in theoretical physics. 

That was the day it was announced that collisions between particles at the Large Hadron Collider (LHC) facility — arguably the most ambitious and audacious science experiment ever — revealed the existence of the Higgs Boson.

The discovery of the Higgs boson, named for Higgs himself, has been vital for the field of particle physics. It was the last occupant of the particle zoo that's needed to complete what's known as the "Standard Model of particle physics," the best description we have of the universe on the smallest of scales.

The Higgs Boson, also called the God particle, is generally credited as having been derived in work Higgs was doing in the 1960s. The Higgs field is what gives mass to the other subatomic particles.

I'm going to go out on a limb and say more people who read here regularly will be familiar with the Higgs Boson than a similarly sized readership at the vast majority of other blogs. Not that there's anything wrong with them.

EDIT 4-11-24 0930 EDT: Forgot the link to the source at the top of the second section - on the notice of Higgs' passing.



Tuesday, April 9, 2024

And the Delta Rocket Family is Done

We watched the final Delta IV Heavy launch early this afternoon, watching the coverage on Spaceflight Now, and going outside to watch at about a minute to go in the count. The trajectory was said to be going East and that appeared to be close if not exactly right. It was definitely more visible than flights to the northeast while not as visible as the ones going south into a polar orbit. The rumble from the three large boosters was very notable and got better as the rocket continued down its trajectory. 

The Delta IV Heavy, one of the world's most powerful rockets, launched for the 16th and final time Tuesday. It was the 45th and last flight of a Delta IV launcher and the final rocket named Delta to ever launch, ending a string of 389 missions dating back to 1960.

At this point it appears the Delta family now belongs to history and we'll never see another Delta launch. The payload niche that Delta IV family has carried for those 45 missions will transfer over to the Vulcan Centaur. United Launch Alliance still has Atlas missions left to fly, but no Atlas Vs have been built for years and once the remaining Atlas Vs fly, their payloads will also switch to Vulcan. As of the start of this year 17 more Atlas V missions were scheduled. It appears the next one will be the Crewed Flight Test of Boeing's Starliner capsule, NET May 6.

Screen capture of today's video, 20 seconds after launch.

Today's payload, NROL-70, was classified. Practically that means that coverage of the mission from onboard cameras is restricted and little is said publicly about the success of the mission. The estimates were that by six hours after launch, they'd have a pretty good idea of the orbit and whether it had gone as designed. That time would have been by 7:00 PM EDT, but nothing solid has been seen online yet. 

While the payload is classified, experts can glean a few insights from the circumstances of its launch. Only the largest NRO spy satellites require a launch on a Delta IV Heavy, and the payload on this mission is "almost certainly" a type of satellite known publicly as an "Advanced Orion" or "Mentor" spacecraft, according to Marco Langbroek, an expert Dutch satellite tracker.

...  In 2010, Bruce Carlson, then-director of the NRO, referred to the Advanced Orion platform as the "largest satellite in the world."
...

When viewed from Earth, these satellites shine with the brightness of an eighth-magnitude star, making them easily visible with small binoculars despite their distant orbits, according to Ted Molczan, a skywatcher who tracks satellite activity.

"The satellites feature a very large parabolic unfoldable mesh antenna, with estimates of the size of this antenna ranging from 20 to 100 (!) meters," Langbroek writes on his website, citing information leaked by Edward Snowden.

Today's launch, though, is more about the launcher than the payload. I've seen this picture in a couple of places but without a key, so I'll try to SWAG one.

Left to right, an early Delta, Delta II, Delta III, Delta IV and Delta IV Heavy.  

Final words to ULA:

"Everything that Delta has done ... is being done better on Vulcan, so this is a great evolutionary step," said Bill Cullen, ULA's launch systems director. "It is bittersweet to see the last one, but there are great things ahead."


Changing gears rapidly, here's something different for anyone who might want to collect a piece of space program history.



Monday, April 8, 2024

Not One Thing Happened Today Besides the Eclipse

As fur as I can tell, not one single thing happened in the world of space, the businesses, or even all of science. Just the eclipse. 

Which is not to say nothing happened to billions of people, going through their everyday lives. People went to work, went shopping, and did lots of different things, it's just that in the array of places I go to look for space-related news the story was the eclipse. Along with the stories I ran over the weekend.

I worked on troubleshooting parts of my sprinkler system that aren't working quite right. Got some household business taken care of. Stuff like that. Sure, I took a picture of the eclipse. We had about 50% coverage, so not very photogenic. Go look at McThag's picture. His is better. Mine had too much cloud in the area when I grabbed the shot.

This picture graced the top of the article on Ars Technica about how members of their staff traveled to see it.

Baily's Beads are visible in this shot taken in Athens, Texas. Image credit to Stephen Clark.



Sunday, April 7, 2024

SpaceX Premiers a New Rideshare Mission

This evening near sunset SpaceX flew the first mission of their new rideshare platform called Bandwagon from the Kennedy Space Center, Pad 39A. 

SpaceX isn't new to the ridesharing market, having launched 10 previous rideshare missions with their Transporter platform, the most recent of which lifted off last month. The first and most memorable Transporter mission launched in January 2021 and delivered 143 satellites to orbit, a single-flight record that still stands today. I found that 2021 date surprising. It doesn't seem like three years ago.

The Transporter platform provides launches to sun-synchronous orbits, which are polar orbits that go over the same places on Earth at the same time every day so that the angle of sun and lighting is the same every day - but not every customer wants to launch to an SSO. It should be mentioned that the term polar orbit doesn't require the satellite go precisely over the north and south poles; deviations to 20 or 30 degrees are acceptable.  Enter bandwagon, which flies to the second most requested orbit, at inclinations of up to approximately 45 degrees and satellites at altitudes of 550 to 605 kilometers. 

The major customer on this mission was the government of South Korea, which launched its Project 425 SAR synthetic aperture radar satellite on the mission, according to Spaceflight Now, and requested SpaceX not show their satellites during the launch coverage.

"On board this mission are 11 spacecraft including KOREA's 425Sat, HawkEye 360's Clusters 8 & 9, Tyvak International’s CENTAURI-6, iQPS's QPS-SAR-7 TSUKUYOMI-II, Capella Space's Capella-14, and Tata Advanced Systems Limited’s TSAT-1A," SpaceX wrote in a mission description.

Transporter missions aren't going away, this just adds another option to get to space. SpaceX's rideshare website shows the two platforms alternating from this point on. 

The only prices to obit I could find mentioned Transporter, so I don't know if Bandwagon launches will cost the same. That number is $5500/kg (= $2500/lb), but said to be going up $500/kg per year - 9% - which is less than everything else is going up due to Bidenflation.  

Liftoff at 7:16PM EDT. SpaceX video screen capture.



Saturday, April 6, 2024

SpaceX, Musk Outline Plans to Increase Starship Cadence

SpaceX is continually trying to increase their cadence at everything they do, it's not surprising they're focused this time on Starship. Cadence won't improve until Starship's performance allows it, making that the main target. 

Today, April 6, SpaceX posted a video to X that appears to be like other "all hands meetings" we've seen before. This one, dated April 4, focused on making life multiplanetary with Starship. Early in the video, Musk states that "Starship is the first design of a rocket that's actually capable of making life multiplanetary." It's right around the 1:00 minute mark in the roughly 44 minute video. To do that, Starship has to be improved to meet its design performance limits.

There's a short teaser on YouTube that doesn't include that important statement. 

SpaceX could attempt to land a Starship booster as soon as the vehicle’s fifth flight as Elon Musk outlined plans to increase both the flight rate and the performance of the launch vehicle.
...

Musk said that the fourth Starship/Super Heavy launch is planned “in about a month or so.” That is consistent with comments by SpaceX President Gwynne Shotwell at the Satellite 2024 conference March 19, where she said that flight was scheduled for early May, pending an updated Federal Aviation Administration launch license. If the company holds to that schedule, the launch would take place less than two months after the vehicle’s third flight.

The goal of the fourth flight is for the Starship upper stage to get through the “high heating regime” of reentry and make a “controlled splat” into the ocean, he said. On the third flight, Starship broke up during reentry.

Musk mentioned that they also want to bring the Super Heavy booster back intact on the next flight, having it land “on essentially a virtual tower” in the Gulf of Mexico - which I interpret to mean it will slow to essentially zero speed above the water and then be lowered into the Gulf.

“If the landing on the virtual tower works, then we will actually try on Flight 5 to come back and land on the tower,” he said. “That is very much a success-oriented schedule, but it is in the realm of possibility.”

The booster for that next flight, B11, was static fired Friday the 5th.

April 5th static firing.  Image credit: SpaceX 

To support a higher cadence naturally requires more hardware. Before the March IFT-3,the company said they had four pairs of ships and boosters at Starbase. Musk said in the presentation the company would build “roughly six” more vehicles this year.

While the emphasis on building hardware naturally has to focus on Starship, Super Heavy boosters, and Raptor engines, don't forget the ground infrastructure - the things Musk refers to as "Stage Zero." You've probably heard that they're building a second launch mount in Starbase Boca Chica; they're also modifying and updating the launch mount at the Kennedy Space Center, next to pad 39A. They expect the KSC launch mount to be operational by the middle of next year.

“What we should probably expect is that we do the development launches here, test anything new here, build the rockets,” he said at Starbase, “and then probably most of the operational launches would be from the Cape.”

You might remember seeing the Raptor 2 engine next to the Raptor 1. There's a Raptor 3 that has been prototyped that's even simpler (fewer parts) than the Raptor 2. 

With the increased production rate will come increased payload capacity. Musk outlined improvements to the Raptor engine that will increase its thrust from 230 to 280 metric tons-force, and “ultimately” to more than 330 metric tons-force of thrust.

Perhaps the most astounding thing I heard about their plans was how drastically the cost per unit of mass was going to be decreased. All of that mostly due to reusability and getting lots of life out of one build.

The engine improvements would support a “Starship 2” that also features a slightly longer booster and ship. That will be able to place more than 100 metric tons into orbit in a fully reusable configuration, Musk said. A future “Starship 3,” about 25 meters taller than Starship 2, would be able to place more than 200 metric tons into orbit in a fully reusable mode. He did not disclose when either Starship version would enter service.

Musk claimed that the future Starship 3 would cost less to launch than SpaceX’s original rocket, the Falcon 1 small launch vehicle, which had a price of about $10 million, because of full reusability. He estimated the Starship cost per launch could fall to as low as $2 million to $3 million.

“These are sort of unthinkable numbers,” he said. “Nobody ever thought this was possible. But we’re not breaking any physics to achieve this.”

200 metric tons - 440,000 pounds - to orbit for $3 million, which is a small fraction of what a Falcon 9 launch costs (I've heard their actual costs are around 20 to $30 million). Launching 440,000 pounds for $3 million works out to $6.80 per pound to orbit. 



Friday, April 5, 2024

Small Space News Story Roundup 33

As always, small stories I found interesting. 

Biden Admin proposes SpaceX Tax Commercial Launch Tax  

They call it a commercial launch tax, but in reality it is a SpaceX tax because they do the vast majority of commercial launches in this country. The vast majority of those are for Starlink, which are SpaceX launching for themselves.

The New York Times reports this as "cost-sharing," saying that commercial airlines pay for the Air Traffic Control network in the US through user fees - passed through to their customers as a tax on launches surely would be passed on to those customers. Commercial space companies are exempt from the aviation excise taxes which fill the Airport and Airway Trust Fund, and in turn pays for the FAA’s work. That fund will get roughly $18 billion in tax revenues for the current fiscal year.

There's one major difference between the aviation excise tax and applying it to commercial launches. Air traffic controllers handle an average of 45,000 daily airplane flights or 16.4 million per year. There were 117 commercial launches last year, which isn't even a tiny fraction of the least significant digit in the 16.4 million. Yes, the launches do involve air traffic control routing around the launch sites for a few hours in the very few places (three? four?) where rockets fly.

Divide that $18 billion tax revenue by the number of flights to get around $1095 tax revenue per flight. Adding that to every rocket flight and assuming 150 launches per year turns that $18 billion to an astounding $18.000164250. $164,250 from 150 launches isn't even one least significant digit in the nice, round $18 billion estimate.

Playing with numbers (while purely for laughs) is hamstrung by not knowing how big the tax proposal is. It's also good to recall that SpaceX already talked about providing funds for the FAA to hire more staff to work on launch licensing.  That said, a commercial launch industry spokesperson had this comment.

Members of the commercial space industry argue it is still at a nascent stage, and taxing the industry is “not appropriate at this time,” said Karina Drees, president of the Commercial Spaceflight Federation.

Some Launch Updates and News 

  • The final Delta IV Heavy, NROL-70 is currently set for Tuesday, April 9 12:53 PM EDT.
  • Starliner Crew Flight Test (CFT) has moved from May 1 to May 6 10:34 PM EDT. While night launches are pretty from here, it will be toward the NE. If the launch is delayed a day or two, the liftoff time will move earlier by about 23 minutes per day (due to the Space Station's orbit).

Polaris Dawn is Getting Closer

While there is no proposed date, the Polaris Dawn mission we've been awaiting is being talked about as "early summer"which could be as soon as late June.

In a series of posts on the social media platform X this week, SpaceX said the Crew Dragon spacecraft assigned to the all-private Polaris Dawn mission is heading into thermal vacuum testing. The thermal vacuum test will expose the capsule to the airless environment it will see in orbit, both inside and outside the spacecraft, when it is depressurized for the first fully commercial spacewalk in history. This capability required modifications to the spacecraft, which last flew in 2021. Billionaire Jared Isaacman will command the mission. He'll be joined by former Air Force test pilot Scott "Kidd" Poteet and SpaceX engineers Sarah Gillis and Anna Menon. [BOLD added - SiG]

No Dragon capsule has been exposed to total vacuum as the mission requires, and modifications include big enough oxygen/air supplies to allow the vehicle to be refilled "a few" times. 

In parallel with modifications to the Crew Dragon spacecraft, SpaceX has designed an upgraded spacesuit to protect the four Polaris Dawn crew members in the vacuum of space. SpaceX hasn't yet revealed the new spacesuit, but Isaacman posted last month that the Polaris Dawn crew completed most of the suit's "acceptance test" procedure, which involved actually putting on the final assembled suits. Upcoming milestones include a test run with the crew members inside the actual Crew Dragon spacecraft, vacuum chamber testing, and mission simulations. Other objectives for Polaris Dawn include flying to a higher orbit around Earth than any human has reached since Apollo, testing Starlink internet connectivity in space, and conducting more than 35 research experiments. Launch is scheduled for early summer.

At the SpaceX facility in Hawthorne, CA, the Polaris Dawn capsule (far back in the middle of the aisle), SpaceX workers and Polaris Dawn crew pose for a picture.  Crew (L-R) Anna Menon, Scott "Kidd" Poteet, Jared "Rook" Isaacman, and Sarah Gillis are in the middle front, without their arms up.

There are no photos of the new SpaceX EVA suits.



Thursday, April 4, 2024

The Time is Zero Hours Zero Minutes Coordinated Lunar Time

The headline here might really be the White House has actually ordered something that makes sense. 

On Tuesday, April 2nd, the White House’s Office of Science and Technology Policy released a document that directs NASA to develop a strategy by the end of 2026 to create Coordinated Lunar Time (LTC), a new time standard based on Coordinated Universal Time (UTC) on Earth but adapted to operations on the moon. 

“As NASA, private companies and space agencies around the world launch missions to the Moon, Mars and beyond, it’s important that we establish celestial time standards for safety and accuracy,” Steve Welby, OSTP deputy director for national security, said in a statement.

UTC is a very useful standard here on Earth, but relativistic effects start to show up in cislunar missions. One of the seemingly bizarre conclusions of special relativity is that clocks change the rate they run as the distance from the center of a gravitational field changes.  Clocks on mountaintops run faster than clocks in valleys, and clocks in cislunar space will run faster than clocks on Earth. To an observer on the Moon, an Earth-based clock will appear to lose an average of 58.7 microseconds per Earth-day with additional periodic variations. If you're used to working in microseconds, that seems like a large number, but it would take around 50 years for it to approach a 1 second difference.

Standard time on Earth is inextricably linked to the day/night interval and the Earth's rotation in 24 hours (approximately, "with additional periodic variations"). The traditions of how the day was divided into hours, time zones and everything else don't seem transferable to the moon. If you pick one point near the lunar equator and define the time the sun rises as zero, the time of sunrise one lunar day later will be close to 28 complete Earth days. Instead of 24 hours, the lunar day is more like 28*24 or 672 Earth hours. The lunar day doesn't need to be exactly 672 hours, but crews working together need to be able to communicate and work with the required accuracy; whether Earth to moon or elsewhere. 

“As NASA, private companies and space agencies around the world launch missions to the Moon, Mars and beyond, it’s important that we establish celestial time standards for safety and accuracy,” Steve Welby, OSTP deputy director for national security, said in a statement.
...
“A consistent definition of time among operators in space is critical to successful space situational awareness capabilities, navigation and communications, all of which are foundational to enable interoperability across the U.S. government and with international partners,” Welby said.

The policy sets four major features for LTC: traceability to UTC, accuracy sufficient for precision navigation and science, resilience to loss of contact with Earth and scalability to environments beyond cislunar space. All of those could be achieved with a similar network of atomic clocks, and times could be based on the SI standard for a second, the unperturbed ground-state hyperfine transition frequency of the cesium 133 atom, to be 9,192,631,770 Hz or 9.192631770 GHz. 

NASA has been working on a concept called LunaNet to provide communications and navigation services at the moon using an interoperable network that could include commercial and international contributions. NASA and the European Space Agency have produced several versions of a LunaNet Interoperability Specification that mentions the creation of a Lunar Time System Standard, although documentation for that has not been developed.

In May 2023, the National Geospatial-Intelligence Agency (NGA) announced it was working with NASA to develop a positioning and navigation system for the moon. The goal, NGA officials said then, was to create a system for users on the moon that works “as accurately and as safely as GPS does on Earth.” That announcement did not go into details about creating a lunar time standard.

Here's a thought. On the equinox we just went through here on Earth, the sun moved from rise to set, roughly 180 degrees in 12 hours. That works out to 15 degrees per hour. Here's a map showing the time zones. Along the top of the frame, the numbers in light blue are each 15 degrees in longitude - one hour in sun position. In the continents, time zones get adjusted too much and look all wonky.

On the moon, what's the practical width for a time zone? Not an hour; the sun goes 180 degrees in 14 days or 336 hours. Much too narrow; an Earth hour is 0.536 degrees. What should time zones be like on the moon?