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First active chemistry on an exoplanet revealed by Webb telescope (nature.com)
156 points by hhs on Nov 23, 2022 | hide | past | favorite | 52 comments



Here's the part explaining the active chemistry:

> The team were also surprised to detect sulfur dioxide, which had appeared as a mysterious bump in early observation data. Its presence suggests a photochemical reaction is taking place in the atmosphere as light from the star hits it, similar to how our Sun produces ozone in Earth’s atmosphere. In WASP-39b’s case, light from its star, slightly smaller than the Sun, splits water in its atmosphere into hydrogen and hydroxide, which reacts with hydrogen sulfide to produce sulfur dioxide.

Wikipedia has this to say about sulfur dioxide in our solar system:

> On other planets, sulfur dioxide can be found in various concentrations, the most significant being the atmosphere of Venus, where it is the third-most abundant atmospheric gas at 150 ppm. There, it reacts with water to form clouds of sulfuric acid, and is a key component of the planet's global atmospheric sulfur cycle and contributes to global warming.[11] It has been implicated as a key agent in the warming of early Mars, with estimates of concentrations in the lower atmosphere as high as 100 ppm,[12] though it only exists in trace amounts. On both Venus and Mars, as on Earth, its primary source is thought to be volcanic. The atmosphere of Io, a natural satellite of Jupiter, is 90% sulfur dioxide[13] and trace amounts are thought to also exist in the atmosphere of Jupiter.

https://en.wikipedia.org/wiki/Sulfur_dioxide

This doesn't necessarily mean that the the exoplanet has active volcanism, but it could be an explanation.


Isn't WASP-39b a gas giant? Is it even possible for such a planet to have active volcanism?


I have got a bet with a friend going that by the end of the decade we will have found life, 500usd heh

I am feeling quite optimistic, the spectroscopy of jwst has me quite pumped... If worst came to happen, I might still be able to eek out a win on my bet with ELT in Atacama... But I think that jwst will be enough!


Hopefully you spelled out the conditions and confidence required for life being found, because I can see it being debatable. We might detect compounds on other planets which to our knowledge can only come about through industrial civilization, but one can argue that there's some other process that is currently unknown to us which could give rise to these compounds.

It's similar to the phosphine discovery on Venus, which is indicative of life but certainly debatable. Though in the phosphine case I think there's debate over whether or not they actually detected phosphine? Regardless, I too am excited about the possibility of detecting signs of intelligent life soon.


Likewise, if/when we find life, how would we recognize it? We have some understood rule sets for life here, yet we have life forms that don't 100% conform to any one of them.

There is no guarantee life on another planet will even have the same DNA structure we have, let alone adhere to the model we've come to agree on for Earthen life. We only have LUCA to understand our own life forms, and zero idea what became and begat LUCA (Last Universal Common Ancestor). The word "Common" is important there, because we know there was a lot of life before LUCA.

I took an Origins of Life course that really opened my eyes about how complicated things get when looking for life at different scales.


It would be astounding if alien life had terrestrial DNA. A lot of scifi movies get this hopelessly wrong.

It's reasonable to expect some kind of DNA-analog: a system, not necessarily using familiar amino acids, that does a similar job.

We live in a relatively cold and squishy regime. I suspect the range of possible DNA-analogs is much wider than we think it is. Many will exist in not-at-all-Earth-like conditions.


I feel like spectroscopy would only give you suggestive evidence of life at best, like if significant quantities of oxygen were detected in the atmosphere of an Earth-like exoplanet in the habitable zone. I think your best bet for direct detection of life would come from Mars rover or maybe a mission to one of the Jovian moons (but AFAIK no probe will arrive at a Jovian moon in this decade). Not sure either will detect life in this decade, but I sincerely hope you win your bet!


Maybe detecting a seasonal cycle for certain compounds will be a very strong evidence. Like the amount of atmospheric CO2 in air changes with seasons on earth.


That also happens on Mars as the ice (CO2) at the poles melts and re-forms with the seasons.


Methane similarly fluctuates on mars. Neither is strong evidence for life. But it remains possible, if unlikely, that some component of these fluctuations could have a microbial origin.


I'd take that bet, because I am one of the universe's born pessimists, but I would be quite pleased to pay $500 to be proven wrong.


Does it count as a win if you only detect proxies ? I mean, consider the "tic-tac" UAPs. If they are robo-ships that have taken some tens or hundreds of years to get here and screw with the US Navy... do they count for your bet ?


What telescope or spacecraft in existence is even capable of detecting life? Maybe a Mars rover could.

JWST is only reporting chemicals inferred because of the way they change the spectrum of light in the atmosphere. That requiresassive concentration of one chemical.


I think thats a great bet. My suspicion is that we'll find life, or at least its precursors inside of the solar system in a similar time frame.


The researchers compared it to the photochemical reactions creating and destroying ozone in the Earth's stratosphere.


I'd be curious to know what it would take in terms of telescope size to directly image a nearby exoplanet.


You might be interested in this video which talks about using the Earth's gravity to create a telescope with a lens roughly the size of the Earth (a terrascope): https://www.youtube.com/watch?v=jgOTZe07eHA

They also have a follow up video about using Jupiter to create a jovoscope and there's also more about creating a telescope using the sun (although since the sensor would need to be so far away from the Sun, we would essentially need to launch a different spaceship for each target that we tried to image).


> They also have a follow up video about using Jupiter to create a jovoscope

Just for fun, if you wanted to form the word from Greek roots instead of mixing Latin into it, it'd be "dioscope".

If you stick with the Latin, it's ambiguous whether the combining vowel should be -i-, agreeing with the Latin root ("joviscope") or -o-, agreeing with the Greek root ("jovoscope").

(And for completeness, if you wanted to do it entirely in Latin, the word would probably be "jovivide", but it is generally Not Done to form verbal compounds like that in Latin, unless the verb you're using is either ferre or gerere [both meaning "carry"].)


Entirely in Latin, "videre" would not be the right corespondent verb for "scope" (from Greek "skopos"), but "spectare" (source of English "spectator"), so one could say in Latin "jovispectum" in the neuter gender (something that looks at Jupiter) or "jovispectus" in the masculine gender, though the latter would be more appropriate for the human who uses the instrument, not for the instrument.

An example of a real Latin word formed in the same way is "circumspectus" (someone who looks around) => English "circumspect", so one could say in English "jovispect".

Word compounds from a noun stem with the last vowel changed to "i" + a verbal stem + the thematic vowel, in either the masculine or the feminine gender, are numerous in Latin and formed from many verbs, not only from "ferre" and "gerere".

For example there are many animal names, e.g. sanguisuga (blood-sucker = leech), caprimulgus (goat-milker = nightjar), ossifraga (bone-breaker = bearded vulture), vipera (alive-baby-birth-giver = viper) and others. There are also some insulting names formed in this way in Latin, but those are NSFW, so you may try to guess them, as they also correspond in English to the pattern *-*er, like "blood-sucker".


> vipera (alive-baby-birth-giver = viper)

This one seems like a stretch?

I'm also curious why you interpret the formation as "noun stem with final vowel changed to i", as opposed to "noun stem followed by epenthetic i".


The word "viipera" (long "i") was contracted from "vivipara" (Latin "v" was pronounced like English "w", which favorised the contraction of sequences like "wiwi" into "wii", in a few words), with also the regular change of the unaccented "a" into "e", which happened in all the older Latin words. "Vivipara" is the feminine form of the Latin word that is the source of English "viviparous".

The vipers are unusual between snakes by giving birth to live young, instead of laying eggs, like most snakes.

Both "noun stem with final vowel changed to i" and "noun stem followed by epenthetic i" have happened.

The former to the stems ending in "a" or "o", the latter to the stems ending in a consonant. An alternative interpretation would be that for the stems ending in a vowel the final vowel was removed and an epenthetic "i" has been added, but this is a more artificial interpretation, because there was never an intermediate stage having an "o" stem or "a" stem without the final vowel.

There also exists one case of an older compound word where the initial noun was a stem ending in "i", but the final "i" has been dropped, and the verb remained as a bare root, without forming a stem by the addition of a vowel: "avspec-", which means bird-watcher (with the nominative written as "avspex", i.e. "auspex" in the modern spelling, the source of English "auspices"), from "avi-" = bird and "specere", the non-frequentative form of "spectare". Another example of an old compound word with no epenthetic "i" and with only the bare root of the verb is "juudic-" = judge (justice-sayer, from "juus" and "dicere"). With the exception of a few inherited old compound words like these, all the compound noun+verb words coined more recently used an "i" ending for the noun and a verb stem terminated in the vowel corresponding to the gender.

While you were partially right that the compounds with "ferre" and "gerere" are the most numerous, for the obvious reason that one can form such a compound word for any object that can be carried, there are a large number of Latin words made from nouns with other verbs.


>Earth's gravity

*Earth’s atmosphere


This got downvoted but it is correct. The "terrascope" concept depends on atmospheric rather than gravitational lensing. The deflection through the Earth's atmosphere is about 1 degree, which is orders of magnitude more than you get from the Earth's gravity.

Using Earth as a gravitational lens would give you a focal point about 15000 AU (a quarter of a light year) away, far outside the solar system. But with atmospheric diffraction, you can get a focal point within the Earth–Moon system.


I’m assuming the lazy downvoters had watched the recent PBS SpaceTime episode that talked about the gravitational lens approach in the context of exoplanet imaging, and just assumed that anything involving earth for lensing was gravity based.


That’s a rookie telescope. Let’s use the sun!

https://youtu.be/4d0EGIt1SPc


Cool topic, but completely unacceptable to rant 20 minutes on tangentially related topics before getting to the actual issue at hand. I understand that Youtube prefers longer videos for monetization, but this is absurd.


This is the most entitled comment I've seen all week.

The video has a clickable chapter list and a time scrubber, and the other chapters are closely related.


That still doesn’t disprove the point though. I like videos that get straight to the topic of the title rather than blabbering.

It’s very frustrating to see deceiving titles and the actual content related to the title is 2% of the entire video..


IMHO, the title is not deceiving. As of right now it's "Turning Earth Into a Telescope", and he talks about just this from a historic standpoint.

If you were hoping for the technicalities of it, then I can see how it's not what you want. I know what I think is enough about the history of telescopes, so I skipped that part, but I thought the history behind how he came up with the idea fits squarely into the title.


“Guide to replacing a toilet float valve” doesn’t need to include the history of plumbing.


No one is clicking a video called "turning the earth into a telescope" to actually "turn the earth into a telescope". They are likely doing it for educational or entertainment purposes.

On the other hand almost everyone clicking a video called "Guide to replacing a toilet float valve" is actually looking to replace a toilet float valve.


Sounds like you have identified an underserved market niche. I look forward to viewing your videos.


"To replace a toilet float valve, we must first start with the big bang..."


I sure look forward to watching "Guide to turn Earth Into a Telescope". I'd expect it to be be a different video.


There are actual (conceptual :D) plans by NASA to use our own sun as a gravitational lens to achieve just that.

The concept is by Slava Turyshev and titled "Direct Multipixel Imaging and Spectroscopy of an Exoplanet with a Solar Gravitational Lens Mission". I'm only a casualstronomer and don't consider myself qualified to provide further details. Should be easy enough to find though!



I actually came across this video on HN a while back: https://www.youtube.com/watch?v=NQFqDKRAROI

It explains the extraordinary idea of using the sun as a gravitational lens.


JWST follow up in planning stages named for Carl Sagan is considerably bigger, optical, and being designed to be able to directly image exoplanets.

https://youtu.be/BIgQpXObjFI


Well, you can do it with an 8m-diameter primary mirror, because it's been done at Gemini Observatory. Keck and the VLT have directly imaged exoplanets as well. See this list: https://en.wikipedia.org/wiki/List_of_directly_imaged_exopla...


I suspect greesil means resolved beyond a point source. We've so far only managed that for stars: https://en.wikipedia.org/wiki/List_of_stars_with_resolved_im... .




As in one solar mass of telescope or just a telescope as wide as the sun's radius?

The latter seems achievable, if tricky.


It uses the sun's gravity as a gravitational lens. You fly a normal sized telescope to the focal point. The theoretical resolution is pretty mindblowing, we'd be able to make out oceans and continents on exoplanets.


The main problem seems to be getting to the focal point, which is 500+ AUs from the Earth.


Imagine a ferrofluid, you could wiggle around a space via electro magnetic forces. You could create parts of a "mirror" at locations on demand, and sythesize the reflected light into a whole picture, without ever needing a huge, ground mirror. The whole optical body is only ever needed for us and parallelistic sensors.


That then could be used to create a super high resolution telescope no?


Amazing. Until today chemistry on planets outside the solar system did not exist. I love how the science advances the world.


It would be unbelievable and terrifying if it had turned out active chemistry on other planets didn’t exist.


It would have been impossible to guarantee the absence of chemistry anyway.

Only the discovery of its existence can end the search.


If we surveyed a million planets and never found active chemistry that would be sufficiently terrifying.

It would be enough to convert a number of atheists to religion… or to simulation theory.

Whereas new telescope = here’s some active chemistry as expected is business as usual.


I'll bet it will turn out to be a piece of chorizo.




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