NASA Shuts down a long-running experiment on Voyager 1

Voyager 1, the darling of deep space, is well into old age, coming up on the 50th anniversary of its launch and the first known thing from Earth to ever leave the solar system. The harsh side of that is Voyager 1 is running low on power and they're trying to keep the old girl going. Over the years, the solution to achieve a longer life has been to shut down old experiments and after much discussion, Voyager project leaders elected to shut down an experiment that has been gathering data since 1977 (with a few short interruptions).

On April 17, engineers at NASA’s Jet Propulsion Laboratory (JPL) in Southern California sent commands to shut down an instrument aboard Voyager 1 called the Low-energy Charged Particles experiment, or LECP. The nuclear-powered spacecraft is running low on power, and turning off the LECP is considered the best way to keep humanity’s first interstellar explorer going.

The LECP has been operating almost without interruption since Voyager 1 launched in 1977 — almost 49 years. It measures low-energy charged particles, including ions, electrons, and cosmic rays originating from our solar system and galaxy. The instrument has provided critical data about the structure of the interstellar medium, detecting pressure fronts and regions of varying particle density in the space beyond our heliosphere. The twin Voyagers are the only spacecraft that are far enough from Earth to provide this information.

The Voyager probes are powered by Radioisotope Thermoelectric Generators, RTGs, which run on small amounts of atomic decay from plutonium, turning the heat generated by the plutonium into electricity. Both Voyagers lose about 4 watts of power every year. The loss of power is something that was undoubtedly considered carefully during the design stages of the mission. All fuel sources run out, and plutonium RTGs are among the best for reliability and long life. After their close flybys in our solar system, the ground crews would order the turn off of power drains, like the video cameras, eventually becoming the only manmade objects to leave our solar system. After almost a half-century in space, the available power has dropped and the margins of "power available versus what you'd like" have grown razor thin, requiring the team to conserve energy by shutting off heaters and instruments while making sure the spacecraft don’t get so cold that their fuel lines freeze.

During a routine, planned roll maneuver on Feb. 27, Voyager 1’s power levels fell unexpectedly. Mission engineers knew any additional drop in power could trigger the spacecraft’s undervoltage fault protection system, which would shut down components on its own to safeguard the probe, requiring recovery by the flight team — a lengthy process that carries its own risks.

The Voyager team needed to act first.

“While shutting down a science instrument is not anybody’s preference, it is the best option available,” said Kareem Badaruddin, Voyager mission manager at JPL. “Voyager 1 still has two remaining operating science instruments — one that listens to plasma waves and one that measures magnetic fields. They are still working great, sending back data from a region of space no other human-made craft has ever explored. The team remains focused on keeping both Voyagers going for as long as possible.”

Years ago, the project managers put together a plan of what to shut down, when to shut it down, in the correct order.

Of the 10 identical sets of instruments that each spacecraft carries, seven have been shut off so far. For Voyager 1, the LECP was next on that list. The team shut off the LECP on Voyager 2 in March 2025.

While the Voyagers are beyond our solar system, and among the fastest things mankind has ever launched, they're not remotely close to the next star system. That's in the vicinity of four light years away, while the Voyagers are barely one light day away. Still, that makes sending instructions to the probes inconvenient at best. That means being really sure the message you're sending is thoroughly tested to know it's correct and once transmitted, the soonest you can know if it worked is another day away. 

Artist’s illustration of one of the Voyager spacecraft. Credit: Caltech/NASA-JPL

Engineers are confident that shutting down the LECP will give Voyager 1 about a year of breathing room. They are using the time to finalize a more ambitious energy-saving fix for both Voyagers they call “the Big Bang,” which is designed to further extend Voyager operations. The idea is to swap out a group of powered devices all at once — hence the nickname — turning some things off and replacing them with lower-power alternatives to keep the spacecraft warm enough to continue gathering science data.

The team will implement the Big Bang on Voyager 2 first, which has a little more power to spare and is closer to Earth, making it the safer test subject. Tests are planned for May and June 2026. If they go well, the team will attempt the same fix on Voyager 1 no sooner than July. If it works, there is even a chance that Voyager 1’s LECP could be switched back on.

I'm not sure what they mean by "about a year of breathing room." Voyager 2 launched on August 20, 1977 with Voyager 1 following 16 days later on September 5. They're closing in on their 49th year in space this coming August and early September with the 50th anniversary the following year. I've been hoping they'd make 50 years for as long as I can remember. 

Today's Space Race is real, and an interesting step is looming

It's no secret that there's an undercurrent of the 1960s Space Race to the moon going on as our returns to the moon start to play out. It's also no secret that what's looking to be the ultimate target of the next round of missions isn't the large, open areas on the Earth-facing side of the Moon, like the Sea of Tranquility was for Apollo 11. Showing up in nearly every large story of the next manned mission to the Moon are references to landing near the lunar South Pole. 

There are big, practical reasons for choosing the South Pole: the day to night temperature swings aren't as large as those in the huge Mare (seas) of the middle latitudes, and there appears to be large amounts of water (ice) available there. 

Currently, the Space Race is that two lunar landers are set to visit Shackleton crater, that is actually on the south pole. 

The two landers will arguably be the most ambitious robotic missions ever sent to the Moon. The Endurance spacecraft, built by Jeff Bezos’ space company Blue Origin, will become the largest lunar lander in history, exceeding the size of NASA’s Apollo lunar module that ferried crews to and from the lunar surface more than 50 years ago. China’s Chang’e 7 mission will feature a smaller lander, but the project also includes an orbiter, rover, and a hopper drone to scout for hidden ice deposits. 

Blue Origin's Endurance lander has just completed some extensive thermal/vacuum tests at Johnson Space Center in Houston. The tests were completed last week, and the spacecraft left Houston on Saturday. It's currently en route from Houston to here (Florida's Space Coast) for final preparations to launch on the company’s heavy-lift New Glenn rocket. NextSpaceflight doesn't show anything about a Blue Origin Endurance launch. Two days before Endurance's trip began, so last Thursday (Apr 9), Chang’e 7 arrived at a spaceport on Hainan Island in the South China Sea to be integrated with China’s own heavy-lifter, the Long March 5. NextSpaceflight shows the Long March 5 but only says No Earlier Than 2026. The source doesn't say much about a launch date other than "later this year."

Shackleton Crater is about 13 miles (21 kilometers) wide, with a surface area roughly the same as the cities of Philadelphia, Las Vegas, or Detroit. The crater measures 14,000 feet (4.2 kilometers) deep. If Endurance and Chang’e 7 land on or near the crater rim, as expected, it would be the first time landers from different nations have operated simultaneously so close to one another on another planetary body.
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The highest crests of Shackleton’s rim offer the advantage of near-continuous sunlight, providing a lander or future Moon base a stable source of solar power right next to a crater floor in eternal shadow, where temperatures are cold enough to preserve ancient ice deposits. The Moon’s polar cold traps, including Shackleton, are attractive targets for future exploration. The ice at these locations could be harvested to supply drinking water, oxygen, and rocket fuel for a lunar outpost.

A mosaic of the Shackleton Crater showcases the power of two lunar orbiting cameras working together to reveal unprecedented detail of the lunar south pole region. Scientists created this mosaic using images from NASA's Lunar Reconnaissance Orbiter and the ShadowCam instrument on South Korea's Danuri orbiter, revealing the dark interior of Shackleton in new detail. Credit: NASA/KARI/ASU

Part of the reason for Blue Origin sending their Endurance lander is that it's essentially their Blue Moon Mark 1 lander that they're preparing for the Artemis lunar landing mission next year.

Blue Origin has not publicly identified the exact landing site for the Endurance test flight, other than saying it will target the Moon’s south pole region. In a social media post last year, Bezos said it would land “near Shackleton Crater.” The south pole lies directly on the crater rim. Endurance will carry a suite of NASA-funded stereo cameras to observe interactions between the lander’s engine plume and lunar soil, along with a laser ranging reflector to help scientists pinpoint the craft’s precise location on the Moon. Blue Origin has not yet revealed what else the mission might do after landing, but getting to the surface intact and upright is the primary goal for Endurance. 

The Chinese officials haven't publicly identified much detail about their mission either. They have said that one of their goals is to “directly confirm the existence and source of water ice” in the south pole region. Chang'e 7 will deploy a rover and a “mini-flying probe” after landing. The rover and drone will carry instruments to analyze and measure the abundance of water ice in lunar soil in and around Shackleton Crater. 

Image of the south pole area from Sky & Telescope magazine.  The Diviner instrument aboard the Lunar Reconnaissance Orbiter imaged the temperatures of the south polar region, shown here. Shackleton crater is at the bottom center, and the south pole is where the thin white lines intersect. The upper left corner of Shackleton crater seems to be the pole.

With both landers targeting the same crater it only seems logical to ask what happens if they interfere with each other? 

The United States and China are parties to the 1967 Outer Space Treaty, which prohibits claims of territorial sovereignty on the Moon and other celestial bodies. But the treaty allows for bases, and it requires parties to the agreement act with “due regard” to the interests of other nations.

In an article published last year, Michelle Hanlon, a professor of air and space law at the University of Mississippi, outlined the advantages of being first at the Moon. The first country to succeed in placing a nuclear reactor on the Moon, for example, could “shape the norms for expectations, behaviors, and legal interpretations,” she wrote.

These first-mover advantages could extend to future lunar bases, mining, and other resource extraction activities on the Moon. NASA has proposed the concept of “safety zones” to avoid interference between the operations of different nations on the Moon.

Lawyers. In my mind, I'm hearing the Morgan and Morgan commercials about "when your property on the moon is damaged by somebody touching it without your permission..."  

NASA Administrator Isaacman talks budget issues

With the Artemis mission is largely done with its distractions, the news is going to switch to the annual budget concerns. The least important word there is annual because congress hasn't actually passed an annual budget since 2009, but while they don't pass an actual budget, they pass funding mechanisms by other names, especially "continuing resolutions" - where the phrase "CR" you'll be hearing comes from - and other forms of what I call an LCS budget (LCS = Lie, Cheat, Steal). 

You may have heard some of the dire reports last week about the White House's NASA budget being significantly lower than congress had wanted. In this year's Space Symposium, currently going on this week in Colorado Springs, NASA Administrator Isaacman gave a talk that covered the topic of working to the White House budget, and reported on by the online industry journal Payload. 

The interview is a two screens full of text that would probably print out to two pages if done at printer settings that would yield a magazine-style page, and it's a good interview, but I will respect their ownership of the written words and not just lift everything, but let me start out with an early Question and Answer:

I saw your early findings on the heat shield. Anything else you can share that you’ve already learned post mission?

I had seen the underwater photos of the heat shield as soon as the divers could transmit them. So I knew when that picture was going around on the internet. I was like, “No, there’s no chunk missing, that’s discoloration that got washed away.” The heat shield looked great. So a lot of credit to the JSC, and the folks at Ames, for doing the right work to get us to flight. 

All that aside, if you’re going to wait three and a half years between missions, just replace the heat shield. 

Other findings are super minor. Orion is a very robust vehicle, with lots of redundancy in systems. So a helium leak in ESM [the European Service Module, attached to Orion]—very, very minor.

We had a water-valve issue—one of four that didn’t perform as expected—but there was no issue accessing drinking water. With the data we’re getting right now, I don’t have the early read on why that primary wastewater line was clearly getting clogged. But these are all very fixable things.

There are several things that Isaacman said that just hit a proper chord with me.  When asked about the big picture lunar and deep space things he has talked about publicly, he gave a good answer: “No one at NASA that I’ve spoken to, at any level of the organization, thought it was a good idea to fly Artemis II and wait three years to try and attempt a [Moon] landing. No one thought that was a good idea.” One of Isaacman's first talks was to turn Artemis III from the lunar landing to a mission intended to test out docking with the landing systems and to increase the launch frequency. The Apollo/Saturn V flew much more often than once a year, although there was irregularity and not always “every  3 months.” I believe the pace is part of doing it properly.  

There was something that Isaacman said that I thought was very healthy. When asked about CLD (Commercial LEO Destination) providers being concerned his approach might be wrong he said, “I’m not surprised that CLD providers didn’t like what we had to say. So prove that we got it wrong.” I like the competition of ideas. “You've got a better idea? Prove it!” 

Jared Isaacman during a talk at the Space Symposium. Image credit: NASA

I think his final Q&A is worth excerpting. Or at least the first answer.

How do you politics-proof your Moon plans?

That’s exactly what we are putting in place. Administrations past have thought the right approach was to make a program that is too big to fail. What they didn’t realize is that you can also make it too big to succeed. 

About the Artemis 2 heat shield questions

I think it's fair to say that everyone who paid attention to the heat shield problems Artemis 1 showed was a bit concerned about them going with the same exact heat shield. One of the YouTube channels I've watched enough to think subscribing wasn't too insane is Alpha Tech, and they posted a video this morning saying that no bad effects like even the excessive wear on the heat shield were seen. It seems I can embed it, so I will. If it goes invisible, here's the link to video itself.

While it's a bit wordy and probably could be a couple of minutes shorter, the trade off is he shows you videos of some major players so that you watch them yourself rather than take his word for it. There are video tracks in there that I've never seen and facts to go with them, so I don't think it's a waste of time to watch it. 

He dives into the reasons for the first test's issue's, the root cause of the first test's shield blowing out chunks, and how altering the trajectory worked. The animations of how the two return trajectories compare are worth the watch. 

For me, I'd have to say the only thing that would make me feel much more comfortable with NASA's fix would be More Pictures. Like the ones that showed Every Single Pit in Artemis I's shield. So we could see what a used but undamaged heat shield looks like.

Three years from now...

I suppose it's a fact of life that when we get a string of very busy news days, the next slow news days seem even slower, even harder to adapt to. So here's just an interesting look at April 13, 2029 - three years from now, but a Friday not a Monday, that we will get the closest known flyby of an asteroid in history, and of the biggest body to ever approach Earth. 

A rare naked-eye asteroid will light up the night sky on April 13, 2029, when the near-Earth asteroid 99942 Apophis makes an extraordinarily close flyby of Earth. For skywatchers, it's a once-in-a-lifetime event — and one worth traveling for.  

This will be one of the closest approaches ever recorded for an object of its size. The night sky will tell a story billions of years in the making. 

At its nearest point — 5:45 p.m. EDT (2145 GMT) on April 13, 2029 — it will pass closer than Earth's geosynchronous satellites, at a distance of roughly 20,000 miles (32,000 kilometers). Just over an hour earlier, at 4:30 p.m. EDT (2035 GMT), it will reach peak brightness, with a magnitude of around 3.1. That's bright enough to be seen with the naked eye from dark locations — but only some locations.

For observers in Europe, Africa and western Asia, Apophis will appear for one night only. An asteroid this big, getting this close to Earth, happens only once every few thousand years, making it truly a once-in-a-lifetime opportunity for a celestial encounter both dramatic and deeply humbling.

To be honest, maybe I'm spoiled, but I don't think a magnitude 3.1 object is going to stand out in the sky. I suppose if we sit outside adapting our vision to the dark, it will be better than if we were to just walk outside from well-lit house in the suburbs but magnitude 3 just isn't going to grab your eyes. If its motion is visible, that will help.

If you poke around, you'll find that Apophis gets talked about pretty often. When it was first discovered, early calculations of its trajectory said that it might hit Earth. Interestingly, that's how it got its name. Apophis, was the Ancient Egyptian God of chaos. As observations improved, the calculated trajectory improved and now Apophis is not predicted to hit, but is still classified as a "potentially hazardous asteroid," not because the current predictions show impact, but because of its size (approximately 1230 feet long) and how close it's going to get. At some point, these predictions have to factor in that we don't know 100% of what's out there that could tweak its trajectory and move it slightly. Especially if it hit Apophis.

Remember our OSIRIS-REx satellite? This is the one that took samples of asteroid Bennu, bringing them back to Earth in September of 2023. If you do recall that, you'll probably also remember that OSIRIS-REx was reassigned to rendezvous with Apophis, getting renamed as OSIRIS-APEX (OSIRIS-Apophis Explorer).

The European Space Agency's proposed Ramses mission aims to launch in 2028 to observe the asteroid up close before and during its flyby, while NASA's OSIRIS-APEX is scheduled to orbit Apophis in June 2029 to see how the close encounter with Earth affected it. ... ExLabs also intends to launch a commercial mission, called Apophis EX, to rendezvous with the asteroid.

A rare stargazing spectacle will unfold on Friday, April 13, 2029, as the asteroid Apophis passes closer than satellites over Europe and Africa in a true once-in-a-lifetime event. (Image credit: Apophis: ESA-Science Office, Earth added in Canva Pro.)

A remarkable and old Ham radio accomplishment

This is actually old news, it happened in March of 2009, 17 full years ago but I just learned about it recently and was embarrassed that I didn't know about it. 

A couple of members of the German AMSAT, a club dedicated to working satellites and more difficult modes, such as Earth-Moon-Earth (EME or Moonbounce) successfully bounced signals off the planet Venus and heard their own signals.  For comparison, the moon is many times closer than Venus and if you're listening for your own signals bouncing off the moon, they take around 2.6 seconds (based on one way distance to the moon of 250,000 miles and the speed of light being 186,000 miles) per second or 1.3 seconds each way.  

It took the signals to and from Venus "a round trip delay of about 5 minutes."  Sounds like Venus bounce isn't very practical for conversation, but I think doing Venus bounce will be like Moonbounce with an automated software system the sends a signal report and another small piece of info, maybe taking a minute to reply, we're talking 2-1/2 minutes there, the message time, and 2-1/2 minutes back, maybe a Venus bounce contact (QSO) could take place in under six minutes. 

I'm full of questions about this, and the source article at the American Radio Relay League has almost no technical details. The ARRL reports, "According to an AMSAT-DL press release, the team's transmitter was generating about 6 kW CW on 2.4 GHz," and that's about all.

I've written about moonbounce and trying to hear my own signal reflections from the moon before; several times. So let me play with some numbers. The first hurdle is how far we're trying to send a signal to. At it's closest, Venus is 24 million miles while at its farthest, it's 162 million miles. Both Venus and Earth are in elliptical orbits around the sun and we're both constantly moving around the sun. There are more complications there, but I'll skip them for now and use a number that isn't the closest or farthest. Since it's a nice round number, let's say 100 million miles. 

The big concern is the same as every communications link everywhere else: the amount the signal attenuates - weakens - over that 100,000,000 miles. The term for this is path loss, and many times I've used a handy equation to calculate it that gets you within less than half a dB of the more theoretically-backed equation. We haven't talked about a frequency, so let me use that 2.4 GHz (2,400 MHz) the Germans used. It's a ham band here in the USA as well. 

Path loss in dB = 37 dB + 20log(f) + 20log(d) where,f is the frequency in MHz and d is the distance in miles.

Path loss in dB = 37 dB + 20log(2400) + 20log(10⁸)

Path loss = 264.6 dB

If you're not used to this world, this may shock you, but the impact in path loss isn't terribly big for the return back to you doubling the distance. If you double the 100 million miles in the last term to 200 million (2*10⁸) the increase is 6 dB. Right, 270.6. There's more uncertainties to come than that 6 dB.

The problem with that number is not knowing how much signal you get back because of a big unknown. How much signal is lost in the reflection sending the signal back to you? It seems a safe bet that your signal isn't going to exactly light up the entire earth-facing side of Venus, it'll be wider than the planet out that far, so there will losses I can't guess at - say your signal's diameter at Venus is 10 times the diameter of the planet, yes, you're losing 9/10 of your signal strength in that reflection. The next problem is how much of what hits the planet reflects? Venus is famously clouded over, how much loss is there? Let me PFA some numbers, and I'll say I lose 20 dB in the combination. 

What does it mean to increase the path loss from 271 dB to 291 dB?

The real problem, then, is not knowing how much loss there is in those places. I'll use the 6000 watts that the German guys did.  That's +67.8 dBm (decibels above 1 milliwatt) If I had no antenna gain the signal I'd get back would be +67.8 dBm minus 291 dB or -223.2 dBm. I don't know of any way to detect and use a signal that weak, regardless of modulation and receiver enhancements. 

What if I had an antenna like the one on the right here, with LOTS of gain?

I don't know exactly how big this is or how much gain it would give at 2.4 GHz, but it's a site in New Jersey where a secret military radar project first bounced radar off the moon. Not with that antenna, it's just a nice looking model for a ham radio project. My guess is the AMSAT Germany guys probably had something like that, if not bigger. 

There's a lot of what I consider reasonable guesses here, and (as always) some "hand-wavium" but it doesn't sound easy - more like on border of impossible. Good antennas for 2.4 GHz aren't hard to get and will do nothing but help. I'm not sure about the amplifier to get 6 kW, but I think they're out there. 

Now that that's over with

Artemis II is in the record books. The reaction comments yesterday surprised me. I was happy the mission succeeded because I don't like the idea of anyone being incinerated to death, and these seem like good people we'd all want to see "live long and prosper," to quote my best, make-believe friends. 

Back in February, I put up a post about the SLS calling it the "biggest and most expensive POS in history." And, yes, I spelled out Piece Of Shit. By no means am I a big fan of where the agency is now, but add that to pretty much everything else that the Big Freakin' Out of Control Government has grown like a fungus in the last 50 years. Look down the right sidebar and at the bottom, the last index is the list of Post Labels I group posts under. I started that in the last 10 years, I think, so it's not perfect, but "big freakin' out of control government" is one of the labels. 

All that to say, NASA has visibly improved since Jared Isaacman took over. I suspect (without good, direct evidence) that it's because of his experience with the modern space industry (Space 2.0 as we tend to call it), flying in SpaceX Crew Dragon capsules a couple of times, when we called him Rook Isaacman. 

As I've said before, all the talk comparing Artemis II to Apollo 8 is wrong.  Artemis II pales in comparison to Apollo 8. Apollo 8 did 10 orbits of the moon, Artemis II didn't go into orbit at all; it was sent on a guaranteed return trajectory meaning there were no critical engine burns or restarts. The most impressive thing to me is that this most expensive POS in history, the SLS, didn't blow up or burn into slag on reentry killing everyone and the Artemis program itself. SLS is over $4 billion per launch. I think it was when Sean Duffy was temporarily head of NASA before Isaacman that someone said there can be no space program at $4 billion a launch. $4 billion here, $4 billion there, pretty soon you're talking real money. 

Isaacman is trying to kill off SLS and congress keeps ordering more missions because it's an easy way to buy votes in their districts. And that's why it's a POS. That and it's a completely unnecessary POS.

SLS is "the most powerful rocket ever built" only until Starship goes orbital. SLS can put more into orbit than Falcon Heavy, but not lots more - it's only like 25 or 30% more. So with some R&D / Non Recurring Engineering done you can launch two Heavies, that together are carrying more than one SLS can for about 8% of what an SLS costs. Don't stop looking for advantages there. Remember all the time and money wasted on hydrogen leaks and fixing them? That's because liquid hydrogen engines are only "best" from one perspective. Falcon Heavies are basically three Falcon 9 first stages with one upper stage. They fly with kerosene (RP-1) and LOX, and they've only flown those Falcon 9s around 400 times, so it's far more common than LH2 and LOX

The SLS has only launched with actual used (already-flown) or leftover Shuttle RS-25 engines, also known as Space Shuttle Main Engines (SSMEs). I'm happy they got a few launches out of them before throwing them out. Those are 512,000 pound thrust – which may have been remarkable in the 1970s but it's common now. Both the Blue Origin BE-4s and the SpaceX Raptor engines, all versions, can do half a million pounds of thrust. The SSMEs cost around $125 Million each. The Raptor 2, 3, or 4 engines are in the vicinity of $2 million each while Blue Origin sells the BE-4 into ULA's Vulcan for less than $20 million.  That means the four engines of an SLS are $500 million, while four BE-4s would cost $80 million. At most. 

Artemis isn't making the future in space, it's holding the future back. As much as I'd like to redirect everything, moving over to the Falcon Heavies and either SpaceX Human Landing System or Blue Origin's Blue Moon isn't in the cards.  

The real future that's being talked about is a space or moon-based economy and that requires a lot of tons sent up to the moon. They'll have to figure out and rotate crews of construction experts, development experts, mining experts and more. There will be a lot of prospecting, so lots of geologists. What's the first thing you see when you look at telescopic photos of the moon? Craters? The leading experts on how these form say meteor impacts, which implies a meteor under every crater. Is that titanium? "Heavy metals?" Gold? Platinum? Osmium? If the moon and Earth "condensed" out of the same part of a cloud of dust or whatever, then it should be the same elements as Earth, but probably distributed differently. More light elements with the heavier ones. There are no volcanoes on the moon, and I'm sure that must have an effect, too. 

I consider this a successful mission because everyone and everything made it back to Earth in one piece and good shape. I really want to see pics of the heat shield but nobody has them online yet. We're not better than we were in the Apollo days but we're better than we've been in a while.  

Looking up at the SLS rocket and Orion spacecraft as they roll to Pad 39B, February 2026. Credit: Stephen Clark/Ars Technica

Hard to think of a better conclusion to Artemis II than that

For the last hour before splashdown and the first 20 minutes or so after it, I was watching the NASA feed as it happened. It seemed that Every Single Milestone they called out was good. The whole time was exceptionally smooth, by the book, and as close to perfect as it gets. 

Odyssey, the Orion capsule, as the splashdown is happening. As close to a perfect conclusion to that as close to a perfect mission as we get.

Go celebrate a little. It's worth it. 

We're in the final 24 hours of Artemis 2

The crew is in the final hours of their mission, which will end Friday evening East Coast time, right around midnight UTC. From the running series of posts on Space.com: 

Orion will begin its plunge through the atmosphere on Friday (April 10) at around 7:53 p.m. EDT (2353 GMT), entering a 6-minute communications blackout. The spacecraft's two parachute groups, its drogues and the main chutes, will deploy around 8:03 p.m. EDT (0003 GMT, April 11) and 8:04 p.m. EDT (0004 GMT, April 11), respectively, with splashdown expected at 8:07 p.m. EDT (0007 GMT, April 11). 

Like everyone who has been on such a historic mission, they haven't really had everything they've been through sink in to their heads. Buzz Aldrin famously went through this after Apollo 11 and being the second person to step on the moon in human history. After something that big, how do you return to an ordinary life? 

"I wanted to resume my duties, but there were no duties to resume," Aldrin said in his book. "There was no goal, no sense of calling, no project worth pouring myself into." 

Tomorrow brings a big test that I think many of us have been fearing.

I think all of you who follow the space program know about the heat shield issues that Artemis 1 had, with holes essentially scattered around the entire heat shield. This has been tested about as well as it could be tested without a "disposable" Artemis mission throwing away an SLS booster to get an Orion capsule on the intended trajectory at the right speed so it could be tested under the worst case conditions.  The results were approved by NASA Chief Jared Isaacman just three months ago.

The Orion heat shield as seen after the Artemis I flight. Credit: NASA

There has been mention in a couple of places of a task for this mission of putting instruments in positions that can track the Orion capsule during reentry to capture images of it. It might reveal details about the reentry that other instruments can't or won't. 

Reentry is always a scary time in a mission. Some reentries are scarier than other. Godspeed, Artemis 2!

NASA working on plans for the new Artemis III

Artemis II is still on the way home and the existing plans for Artemis III were scrapped just over a month ago, but the agency under Jared Isaacman isn't wasting time trying to reduce the wasted time between missions. 

NASA Administrator Jared Isaacman said Tuesday afternoon that the space agency is debating about which orbit to fly Artemis III in before locking in a blueprint, noting that the first “senior level” Artemis III mission design discussion had taken place earlier in the day.
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“One of the questions is what the initial orbit will be for Artemis III,” Isaacman said during a news conference. “Is it going to be LEO or HEO? There are pros and cons for each of them, for sure.” 

Most readers will remember that Artemis III was originally scheduled as the first Artemis moon landing, and the date being talked about was originally 2025 but was most recently looking to be 2027. Artemis I was in November of '22, so about 3-1/2 years from flight one to two. Having III even at the end of '27, would be an incredible amount of progress. Plus the mission has been massively changed, so that instead of a lunar landing next year it's looking to be restricted to Earth orbit for a test of one or (preferably) both lunar landers, SpaceX's Starship-based Human Landing System or Blue Origin's Blue Moon Mark 1.

The first question, though LEO or HEO has to be decided quickly because it affects other decisions. Low Earth Orbit is commonly referred to as 100 to 1240 miles (2000 km) while High Earth Orbit ranges from there up to 22,400 miles. 

A rendezvous in low-Earth orbit would potentially allow NASA to fly the SLS rocket without using an Interim Cryogenic Propulsion Stage, or ICPS. This is valuable because it could then save this final remaining ICPS stage for the Artemis IV mission (for future SLS missions, NASA would use a Centaur V upper stage, also provided by United Launch Alliance). For an Artemis III mission in a higher orbit, however, NASA would need the ICPS to push Orion there. 

A rendezvous in high-Earth orbit would better mimic thermal and other conditions near the Moon, and this might be a more benign environment for the Orion spacecraft, which is sensitive to thruster pluming and other thermal issues. High-Earth orbit would also provide a stiffer test for Orion’s modified heat shield.

The concept of doing this mission as a test of rendezvous and docking with the lunar landers is just plain common sense. It was done during the Apollo program two missions before Apollo 11's first landing. Apollo 9 took place in low-Earth orbit between 125 and 310 miles.  

The biggest question hanging there in my mind is which lander will be ready before the end of '27. Will they both be ready? The answer is both seem to be progressing as intended. The launch of the next Starship test flight was said to be "in March" but I've seen May mentioned lately. Part of that could be there was a latest version Raptor 3 engine that blew up in the last week during testing, but while engines blowing up isn't necessarily a design problem, it seems prudent to make sure it's not something that needs redesign. Blue Origin’s Blue Moon Mk. 1 lander is said to be “wrapping up” vacuum-chamber testing at Johnson Space Center in Houston.

Blue Origin's Blue Moon Lander. Image credit: Blue Origin

Final words to Eric Berger from Ars Technica.

Isaacman said it is important for SpaceX’s Starship and Blue Origin’s New Glenn rocket to reach higher launch cadences to support not just Artemis III but many future missions to the lunar surface. NASA is clearly watching both closely.

“We’ll all have a sense of which path we’re going to go down based on launch cadence of our two HLS (human landing system) providers, both of which have launches coming up in the next month or less,” Isaacman said. “A big key to our strategy—to not just return to the Moon but to stay and build a base—is the rapid reusability of heavy-lift launch vehicles. The more they get experience doing that, the more options that are available to us for Artemis III.” 

Catching up a bit

The flood of data from the Artemis 2 flyby is being posted in glorious high definition, and large files to NASA's usual places: Flickr, and NASA's images page. Artemis II has its own "Mission Science Page" that features some nice photos, too, just not strictly the flyby pictures.  The second one, is page of 1 of 15 from only this year and none of the pages appear to be sorted in any logical way. For example I went to page 15 figuring those should be the most recent pictures and a couple of side by side pictures were from before the mission launched and last night's. 

The usual space-related news sources might be easier on your nerves. Both Space.com's article and Ars Technica's have a small sample but good pictures.  

The Moon, seen here backlit by the Sun during a solar eclipse on April 6, 2026, is photographed by one of the cameras on the Orion spacecraft’s solar array wings. Orion is visible in the foreground on the left. Earth is reflecting sunlight at the left edge of the Moon, which is slightly brighter than the rest of the disk. The bright spot visible just below the Moon’s bottom right edge is Saturn. Beyond that, the bright spot at the right edge of the image is Mars. Credit: NASA

On Saturday (4/4) I commented that Comet MAPS appeared to have disintegrated. I didn't see that confirmed until this morning, Apr 7th. 

The much-heralded Comet MAPS, proclaimed by some as "The Great Easter Comet," met its end this past Saturday (April 4). The comet apparently underwent a cataclysmic fragmentation just hours before it was to make its closest approach — called perihelion — to the sun. Such was not completely unexpected, for Comet MAPS was a Kreutz sungrazer, a type of comet that comes literally within a hairbreadth of the sun. They may all have evolved from the breakup of a usually large comet's close approach to the sun, perhaps a millennium ago. From this progenitor, countless fragments of different sizes have been circling the sun in similar orbits.

An extended afternoon of watching Artemis' big day.

Must be that I'm too much of a space nerd.  

Space.com posted a schedule of what would be seen during the day, and here's an attempt to copy it. I sat down to watch a bit before the 1:56 PM (red) line and as I'm typing it's 9:40 PM and this schedule says the livestream is about to end. 

Time (in EDT / GMT)	Event	What to know
10:50 a.m. EDT / 1450 GMT	Artemis 2 crew wakes up	This begins Flight Day 6. Flyby day. NASA will play the crew a song.
1:00 p.m. EDT / 1700 GMT	NASA's main livestream begins	This is a special broadcast. The 24/7 feed will transition to this.
1:56 p.m. EDT / 1756 GMT	Artemis 2 surpasses Apollo 13 distance record	The Orion ship will fly farther than Apollo 13, going beyond 248,655 miles from Earth.
2:10 p.m. EDT / 1810 GMT	Artemis 2 crew comments on beating Apollo 13 record	The Artemis 2 crew will comment on their new record, but we'll get audio only.
2:15 p.m. EDT / 1815 GMT	Orion cabin configured for flyby	The astronauts will darken the cabin lights and prep cameras and other gear.
2:45 p.m. EDT / 1845 GMT	Seven-hour moon flyby observation period begins	The Artemis 2 crew will observe both near and far sides of the moon. The main phase lasts five hours.
4:35 p.m. EDT / 2035 GMT	Interior views of Orion	NASA will show inside views of Orion during the flyby.
Ongoing.	Observations continue.	The crew has 35 targets for 10 science objectives. They may see the Apollo 14 and Apollo 12 landing sites.
6:44 p.m. EDT / 2244 GMT	Loss of signal	NASA will temporarily lose contact with Artemis 2. It should last 40 minutes.
7:02 p.m. EDT / 2307 GMT	Artemis 2 closest to moon	Orion will be about 4,070 miles above the moon at closest approach.
7:07 p.m. EDT / 2307 GMT	Artemis 2 reaches its farthest point from Earth	Orion will be at its farthest from Earth, at about 252,760 miles away.
7:25 p.m. EDT / 2325 GMT	Reacquisition of signal	Mission Control should reacquire signal with Artemis 2.
8:35 p.m. EDT / 0035 GMT on April 7	Artemis 2 sees solar eclipse	The astronauts will see the moon block the sun in a total solar eclipse. It will last 53 minutes. They may also observe Mars, Mercury, Venus and Saturn.
9:20 p.m. EDT / 0120 GMT on April 7	Artemis 2 lunar flyby observation period ends	The flyby observing period ends. The crew begins sending some imagery to Earth.
9:32 p.m. EDT / 0132 GMT April 7	Solar eclipse period ends	The Artemis 2 crew finishes observing the sun's corona and planets.
9:45 p.m. EDT / 0145 GMT April 7	NASA's Moon Flyby Livestream ends	NASA's special Artemis 2 moon flyby commentary ends, but 24/7 mission coverage continues

The day was filled with video highlights and incredible sights.  Along with hours of nothing like those highlights.  Along the way, I grabbed this picture that's one of the more incredible sights of the night.

The captured video scene is slightly stretched left to right, but along the right side you see a tiny bright crescent next to much larger, but less well-lit, grayish-brown crescent. The big crescent is the moon; the small one is Earth. The Earth is starting to be occulted (the astronomical term when one object blocks out one farther behind it) by the crescent moon. 

There has been a lot of talk about the astronauts on this mission seeing things no astronaut has seen since 1972, or ever before, but a couple of things here - like this photo - have never been seen by any human at all. I'm sure it could have been seen if prior moon missions were timed exactly right, and I'm equally sure nobody scheduling those moon landing missions would have thought of this. Seeing this is a sign of the beginning of the age of a space-faring civilization.

 

 

It's Resurrection Sunday - Happy Easter

 

It's Easter, Resurrection Sunday, and as I do regularly, I look at what I've posted for the major holidays in the past, and often modify them quite a bit. Not wholesale tear it up and start over, but some extensive additions and deletions.  FWIW, this one is largely unchanged from 2024.

Looking for the Living One in a Cemetery

Luke 24: 1-12 New Living Translation

24 But very early on Sunday morning^[a] the women went to the tomb, taking the spices they had prepared. ² They found that the stone had been rolled away from the entrance. ³ So they went in, but they didn’t find the body of the Lord Jesus. ⁴ As they stood there puzzled, two men suddenly appeared to them, clothed in dazzling robes.

⁵ The women were terrified and bowed with their faces to the ground. Then the men asked, “Why are you looking among the dead for someone who is alive? ⁶ He isn’t here! He is risen from the dead! Remember what he told you back in Galilee, ⁷ that the Son of Man^[b] must be betrayed into the hands of sinful men and be crucified, and that he would rise again on the third day.”

⁸ Then they remembered that he had said this. ⁹ So they rushed back from the tomb to tell his eleven disciples—and everyone else—what had happened. ¹⁰ It was Mary Magdalene, Joanna, Mary the mother of James, and several other women who told the apostles what had happened. ¹¹ But the story sounded like nonsense to the men, so they didn’t believe it. ¹² However, Peter jumped up and ran to the tomb to look. Stooping, he peered in and saw the empty linen wrappings; then he went home again, wondering what had happened.

---

Coming from my background, becoming an evangelical Christian was a large change.  I had studied biochemistry and microbiology in college through my third year before life imposed some detours, eventually getting my degree and starting my career as an engineer late in life (over 30).  I had been an amateur astronomer since about age 10, so between them I was deeply marinated in the standard model of Cosmology as well as conventional biological evolutionary theory.  Frankly, I wasn't giving it much thought any longer, but my wife had re-affirmed her faith (she had first accepted Christ as child) and I was having all of my mental models disrupted.  She had started a subscription to Bibical Archaeology Review and the constant refrain from archaeologists, not religiously motivated, along the lines of "we thought this was old Jewish folklore, but here it is" got me thinking "if that's true, maybe there's more that's true."  Strobel's The Case for Christ, played a role in filling in the gaps in my historical knowledge.  

I went forward for Baptism in 1995 in an evangelical church and an important part of that change was because the pastor had a similar background to mine, at least in the biochemistry/microbiology. He was a pharmacist and the director of the pharmacy department in one of the local hospitals. He quickly became one of our closest friends in the worst time of our lives - Mrs. Graybeard's cancer in 1997. It's a long story, but in the last couple of years the church's elders dumped him. As the story came out, we found a new church - a nearby Southern Baptist church. Our pastor started going to another Southern Baptist church, but closer to his home. He passed away a little before Easter of '24.  

Easter is the most important day in Christianity and far more important than Christmas because of the resurrection.  Everyone has a birthday, but history only records one resurrection.  The resurrection is essential to Christianity; without it there simply is no reason for Christianity to exist.  Since virtually everyone, including honest atheists, agrees Jesus was a real man in history (I've always found it amazing that Jesus' existence is better attested in ancient sources than that of Julius Caesar - but no one claims Julius Caesar was not a real person) and died on the cross, the question becomes whether or not it can be verified that Christ was seen after the resurrection by someone other than the closest circle of disciples. Strobel says:

Did anyone see Jesus alive again? I have identified at least eight ancient sources, both inside and outside the New Testament, that in my view confirm the apostles’ conviction that they encountered the resurrected Christ. Repeatedly, these sources stood strong when I tried to discredit them. 

Could these encounters have been hallucinations? No way, experts told me. Hallucinations occur in individual brains, like dreams, yet, according to the Bible, Jesus appeared to groups of people on three different occasions – including 500 at once!

In the end, after I had thoroughly investigated the matter, I reached an unexpected conclusion: it would actually take more faith to maintain my atheism than to become a follower of Jesus.  

I still think a great summary is "Five Confounding Facts About Jesus' Resurrection" a 2016 post at Donald Sensing's Sense of Events, which has been gone for a while and replaced by Sensing Online.  He has done several excellent posts on the subject, including Jesus and History and links to articles put together by working scientists, "On what basis would a scientist accept the Resurrection?" and "Is Belief in the Resurrection Unscientific?" Do yourself a favor and read this year's (2026's) Easter post at Sensing Online. 

Enjoy your day and your time with your family. I actually woke at 3AM this morning telling myself I forgot to do an Easter post. As I've said almost every year, churches seem more crowded on Christmas than Easter but everyone has a birthday while there's only one who had a resurrection.  That's more important than a birthday.

 

Ham radio and Artemis 2

Before I get to that, a short update on the comet story. While I haven't seen an actual headline comet MAPS appeared to break apart in a video I saw that was made as the comet was getting close to going behind the blocked out visual center of the Lasco camera's center of view. The latest view, time tagged at the same 2306 UTC that previous posts displayed, shows nothing has come out from near the sun. 

This tells me that the comet was ripped apart by something in that environment. Not only is this not unexpected, it's rather common for these Kreutz sungrazers. 

Late in the afternoon, I ran across an interesting story for those of you interested in radio, ham radio, and experiments you can do yourself.  It focuses on how hams are tracking Artemis 2.  It opens with what I find to be an interesting thing I haven't heard yet. Three of the four Artemis 2 crew are hams. Commander Reid Wiseman, is KF5LKT;  Canadian Mission Specialist Jeremy Hansen is KF5LKU, the next call issued, and Pilot Victor Glover is KI5BKC (so he's been licensed longer). You'll note that the only astronaut who isn't a ham is the YL Mission Specialist Christina Koch. 

The story itself is from a Vancouver, British Columbia newspaper called the Vancouver Sun. Vancouver is about as far as one can get from Florida's Kennedy Space Center and still be in North America. The story they present is almost entirely centered on Vancouver native named Scott Tilley who is apparently not a ham, they never say or give a callsign for him but a contractor on a program NASA started. 

This week, he is tracking NASA’s Artemis II rocket as one of 34 individuals and organizations from around the world selected by the American space agency to monitor its first crewed mission to orbit the moon in more than 50 years. 

Here's where the ham community kicks in. QRZ member K6CLS adds: 

The 13cm EME guys are tuning in. Orion xmits downlink on 2216MHz +/- 2.5MHz. easy to see the continuous signal with some gain from a dish and a good preamp.

To look at the spectrum, some folks are using a down converter to an SDR, or an SDR that can work on 2216MHz, or a spectrum analyzer directly!

Can see the chips in the signal, so it looks like QAM something, but I'm sure it's more complex.

Several folks have reported they can see the Doppler shift in the mark tones.

Fun stuff!

As you can see by him specifying the downlink at 2216 +/- 2.5 MHz, is part of S-band (2.0 to 4.0 GHz) communications (the way NASA is using it), the 13cm ham band is close to the 2.4 GHz WiFi band, so some folks online may have some means of tuning in the band - if you're comfortable working with microwave frequencies near that to tack in coax or power splitters, amplifiers and other kinds of modules.  EME is Earth-Moon-Earth communications or Moon Bounce. Wikipedia notes, 

"The first Earth-Venus-Earth contact by amateur radio operators was established on the 13 cm band in 2009."

That's in case that Earth-Moon-Earth stuff is too easy for you. I honestly didn't know anyone anywhere had done Venus Bounce or EVE before.

If you're interested in trying to put something together to listen for Artemis 2, I don't know of any really easy, off the shelf solutions because I haven't looked. A quick look at some broadband SDR companies whose products I've used don't show any that are rated for 2.0GHz to, well, anything. That basically just implies that you need to use a block downconverter from 2216 MHz down to something you have that would allow you to play with the signal. I'll have to play more with this idea. 

A little bit more of that

The latest MAPS photo, exactly 24 hours from April 2nd: brighter and closer to the sun than yesterday. 

And for your convenience, here's both days in one graphic: 

Tomorrow will be the "do or die" day for Comet MAPS; at around 0800 UTC on the 4th, or about 4:00 AM EDT Saturday morning, the comet will go behind that large dark blue circle for its closest approach to the sun. According to the Central Bureau for Astronomical Telegrams (CBAT) Circular#5675, Comet MAPS will pass within 101,100 miles above the sun's surface (the photosphere) at 10:24 AM EDT (1424 GMT).

If it survives that closest approach, we don't get to know until it comes out from behind that dark circle and I'll SWAG 1900UTC Saturday, or around 3PM EDT. 

I'm not sure how I'm going to try to watch this. I have a solar filter for a telescope but more study is required and life has been throwing lots of interruptions at us. 

A little bit of this, a little bit of that.

A little bit on Artemis 2...

NASA's Artemis 2 Orion spacecraft successfully performed its translunar injection burn, or TLI, in a 5 minute, 55 second maneuver that sent the probe beyond Earth orbit -- the first time astronauts have done so since Apollo 17 in 1972.

The burn began on time at 7:49 p.m. EDT (2349 GMT), 1 day, 1 hour and 14 minutes into the mission.

"Integrity, looks like a good burn," Mission Control Capcom Chris Birch radioed to the crew.

The Orion spacecraft stack came within 115 miles of the Earth's surface, which must have been near it's perigee. The source says they raised their perigee twice today but didn't say exactly what it was. The TLI burn will push the spacecraft into a free return path that will loop around the moon and get flung back toward Earth by the Moon's gravity. That far point is being described as the farthest from Earth humans have ever been, and will allow them to see the entire lunar farside in one view, rather than the close approaches of the Apollo era. 

A little bit on comet MAPS heading into it's closest approach to the sun.

Comet MAPS is now visible in the latest photo from SOHO's LASCO C3 camera, timed (as printed in the lower left hand corner) at 2306 UTC or 7:03PM EDT. MAPS is small and easy to miss, so I put a red circle around it.

If you compare this image to the one posted Tuesday, it's about midway between the first two points on the lower line of the predicted path - the approach to the sun - marked Apr. 2 12h UT (2PM EDT) and Apr. 3 9H UT (5AM EDT). In other words right where you'd expect it to be within an hour or so.

Tomorrow ought to be interesting to watch the Lasco camera. The position prediction plot from Tuesday shows the comet moves from that 5AM tomorrow morning position just mentioned almost to the point where the large (dark blue) blocking circle covers it. 

Artemis II Step One is a winner - one down lots to go.

The first step of Artemis II, the big step from sitting on launch pad on the ground to Earth Orbit appeared indistinguishable from perfect. There were a couple of oddities during the countdown, that delayed the 6:24PM EDT launch to 6:35, but liftoff and the milestones went almost as boringly perfect as the typical Falcon 9 flight - and that "almost" qualifier was because the flight profile wasn't the same as the Falcon 9's. I've watched hundreds of Falcon 9 launches, so I'm used to the times that the major milestones come on.

The sky was surprisingly clear and blue; surprising because it was completely overcast earlier in the day and some showers were blowing onshore both here and up on the Cape. Thankfully, that was closer to 3PM (1500 EDT) and long gone by launch time. We were able to watch the launch on its path that seemed close to due east, until the solid rocket boosters dropped. Which seemed later in the flight than the two side Falcon 9 boosters drop off a Falcon Heavy. It was pretty from 35 miles south of the launch, but not very loud and the (much) smaller Falcon launches regularly rattle our doors and windows more than the much bigger SLS. I chalk that up to weather.  

Artemis II ascends from Kennedy Space Center, Florida. Credit: Stephen Clark/Ars Technica

And about three minutes later (I think)

The solid rocket boosters (SRBs) detach after NASA's Artemis 2 Space Launch System rocket carrying the Orion spacecraft lifts off from Launch Complex 39B at Kennedy Space Center on April 1, 2026 in Cape Canaveral, Florida. (Image credit: Chip Somodevilla/Getty Images via Space.com)

Of course this is all about the first hour of a mission that will last on the order of 10 days. Credit where credit's due, a successful start is always a good thing, but doesn't mean a whole lot about the next 10 days. Not to mention that the vast majority of the media will be covering this. We should know by tomorrow if the life support systems operate as needed; and if they don't work properly the mission will be aborted. I'll be watching this as I'm sure most of you will be.