NASA's Juno mission leaves legacy of science at Jupiter | Hacker News Reader

NASA's Juno mission leaves legacy of science at Jupiter

scientificamerican.com

99 pointsapress36 comments

This is a fantastic recap of everything Juno discovered and the value of this kind of mission - there’s multiple discoveries in here that are at odds with our theoretical understanding of planetary formation, physics, and chemistry that can inform new science moving forward. One that stuck out to me in particular was that Jupiter’s massive magnetic field isn’t generated by a metallic core like we expected, but rather Hydrogen under pressures sufficient to tear free electrons.

Combine that with the fact that the Juno probe has now more than doubled its expected life, and this whole mission serves as as good of an argument for continuing to fund NASA as you’re going to see.

These are the pictures from the camera, incredibly beautiful stuff

https://science.nasa.gov/gallery/junocam-images/

Wow, they're indeed incredible. What sights. Thanks for sharing that follow up.

https://archive.ph/pwVDL

> the solar system’s undisputed heavyweight

Now I feel the urge to dispute this!

don't be so hard on yourself, there are plenty of low-calorie alternatives nowadays

It's an odd choice of words since 1. Most people know it's the largest and heaviest planet 2. They didn't specify planet but are still ignoring the sun, which is 1000x Jupiter's mass.

Interesting, for me it was quite poetic and a phrasing I specifically noticed and enjoyed. I guess I did know Jupiters the biggest, but wouldn't have been 100% on it, or on heaviest. Not that I'd have a better suggestion, just not something much in my mind, so the framing was nice. I didn't think of the sun at all for some reason. Guess my solar system association is with planets.

I do hope that Juno gets another extension. It's obviously worth it. Its mission is an impressive demonstration that no sooner do we take a closer look at something than we realize we knew nothing and don't understand what we find.

OT: So if Jupiter is something of a "failed star", how much bigger would it have to be to be a successful star, and what would be the effect (if any) on other planets' orbits, and would it boil away a lot of Saturn ?

Wikipedia says it would need to be 75x more massive in order to start fusing hydrogen.

https://en.wikipedia.org/wiki/Jupiter#Size_and_mass

I wonder then how this idea of "failed star" got um started.

Ever since I've seen the Apollo 11 press conference, I don't know what to think: https://youtu.be/BI_ZehPOMwI

why? it’s a press conference of the people with the most eyes on them in the world, not a celebration

Aren't NASA considering the proposal to rendez-vous with 3I/ATLAS (aka C/2025 N1 ATLAS)??? [1]

1: https://www.sciencealert.com/nasa-probe-could-intercept-inte...

Nobody at NASA takes anything Avi Loeb says seriously.

It also happens that NASA is too busy doing damage control to consider anything new. But even if they were, it won't be because Loeb suggested it.

I have seen him speak several times. Does anyone take him seriously?

We live in an age were people take Trump seriously.

Quite sad really

In case anyone else is wondering, it's this guy: "Since 2017, Loeb has argued that alien space craft may be in the Solar System [like] ʻOumuamua"

What I don't understand on his Wikipedia page is this bit in the second sentence: "Loeb is the Frank B. Baird Jr. Professor of Science at Harvard University". Does he work there under the alias "Frank B. Baird Jr." or what does this sentence mean? Or is the position called one person but another person fulfills the role?

Usually just means the position is sponsored by a donor (in this case Frank B. Baird Jr.). Salary and sometimes other funding gets paid via endowment set up by the named person or someone else on behalf of the named person.

While I am not familiar with this particular instance, universities will often have a permanent professorship, or chair, with a specific focus that is named either after a renown expert in the field who taught at that institution, or after the person or organization who funded (endowed) the establishment of that position.

As for Loeb himself, I'm only passingly familiar with him in passing because of coverage since ‘Oumuamua, but it seems like he is a fairly typical asgtrophysicist who decided for some reason that he would launch a crusade declaring anything entering the Solar System from interstellar space must be an alien probe or spaceship.

Frank B. Baird Jr. was the son of Frank B. Baird, of Buffalo New York, who died some time around 1947. His son, and Flora M. Baird, his widow, set up a charitable trust in his name which did things like donate to the Buffalo Museum of Science. The later Frank B. Baird Jr. Foundation made several donations to Harvard for scholarships and the like in the 1950s.

[flagged]

You're yet more proof that humans cannot competently administer the Turing Test. That was me writing.

Please don't do this here. If a comment seems unfit for HN, please flag it and email us at hn@ycombinator.com so we can have a look.

>Nobody at NASA takes anything Avi Loeb says seriously.

source > bloviating

>But even if they were, it won't be because Loeb suggested it.

Wow, what an utter arbitrarily position-hedging comment

No, they are not, because the probe doesn't have anywhere near enough fuel to do this. I suggest stopping use of any news source you have that would print this crap.

You can read their paper here[0]. I agree it's very dodgy (and without even looking at that author's past). While the comet 3I/ATLAS approaches within 53 million km of Jupiter (0.3 au), all they can propose is, optimistically, to bring Juno to within half that distance–27 million km. Hardly seems worth the risks? And that'd end all of Juno's remaining Jupiter science (assuming the MAGA! FY26 budget doesn't get to it first. It's fully defunded, if anyone hadn't heard).

Referring to their figs. 3–7, that distance figure is a hard limit—there's no possibility they have of getting closer to the comet than that.

(Keep in mind this is just one random interstellar comet; there are many, many others like it—there will be infinite opportunities to study one—and Avi Loeb is a proven clown who consistently misrepresents these things for drama).

[0] https://arxiv.org/abs/2507.21402 ("Intercepting 3I/ATLAS at Closest Approach to Jupiter with the Juno spacecraft")

Tangential remark: there was a similar proposal for the end-of-life of the Cassini orbiter—it didn't happen, but, there was enough delta-v for the theoretical option, of escaping Saturn and redirecting it to a second mission at Uranus[1]. It was also a dodgy idea, since the transfer time would have been ridiculous (~20 years)—it'd have been a long-shot for Cassini to have survived that long.

[1] https://en.wikipedia.org/wiki/Cassini_retirement#End_of_miss... ("Cassini retirement#End of mission options")

> without even looking at that author's past

It is worth noting that this comes two weeks after the authors posted https://arxiv.org/abs/2507.12213 "Is the Interstellar Object 3I/ATLAS Alien Technology?"

They describe this first paper as "largely a pedagogical exercise" - clearly, if they're now providing emails to news outlets recommending this course change, their view of the target audience has certainly evolved. Orson Welles would be proud.

>Hardly seems worth the risks?

Juno's mission is at end-of-life at the proposal's starting point. So now tell me again about the risks.

It's not going to be able to see anything at the closest approach that we can't see from earth. So there are no gains to be had, so no risks are worth it.

And even the 27Mkm number requires very optimistic assumptions, including that the main engine that has had huge problems during its mission would work perfectly for one continuous burn to exhaustion. Realistically, that's not going to happen.

I was somewhat suspicious that a probe could perform such a feat, but the article mentioned Avi Loeb, an award winning Harvard scientist [1], the author of the proposal, even went as far as computing required trajectory, ignition etc. so I assumed he had all the necessary data, and it was possible.

1: https://en.wikipedia.org/wiki/Avi_Loeb

I don't think considering his proposal might have damaged NASA's reputation. I also don't think the interstellar object is an alien probe, I just was excited we got a chance at looking at an interstellar object, that may be totally unlike Solar System objects, and possibly far older. Crap?

Avi Loeb is a crank. He's a guy with a career largely behind him swinging for the fences for one big hit that secures his legacy.

its really interesting to see once-professional/respectable people turn into cranks over time... i wonder if they were always that way or just lost their minds, or have they just become cynics and just grift their way to money...?

>I don't think considering his proposal might have damaged NASA's reputation. I also don't think the interstellar object is an alien probe, I just was excited we got a chance at looking at an interstellar object, that may be totally unlike Solar System objects, and possibly far older. Crap?

There's one image on the NASA page and others. Any more links?

https://science.nasa.gov/solar-system/comets/3i-atlas/

https://esahubble.org/images/heic2509a/

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