Astronomers may have found the first exomoon

bellowsgulch

I nominate Moon 2: Electric Boogaloo.

pelagicAustral

I know this is besides the article and all, but why would the Chilean flag be the only one to have 8px left margin? This is killing me... <div style="margin-left: 8px" title="Chile" class="sprites-flag_cl"></div>

benabbott

this would actually be a planet, based on my understanding of celestial bodies? moons are natural satellites orbiting planets. this "moon" is orbiting a brown dwarf.

Foskya

I guess it is more of a derivative of the question: "in which bucket should we put the brown dwarf? Is it a star or a planet?". The answer is neither of course; but since it is more closely related to stars than to planets, I'm more inclined to call this satellite an exoplanet (instead of exomoon). That being said it is still a nice finding, way more difficult to discover than "normal" exopanets.

HelloUsername

An important phrase from the article to consider before commenting: "This system is somewhat hard to define using Solar-System-based words like ‘planet’ and ‘moon’"

hdz

A small dense planet, which orbits a star, is orbited by a larger gaseous moon. It's interesting the discovery is in Chile which has some of the best night skies, a Class 1 on the Bortle scale specifically in the Atacama Desert. Hoping to make it out there one day.

walrus01

> Instead, it circles a brown dwarf, an object larger than a planet, that orbits the CD-35 2722 star. Isn't the dividing line between the largest possible gas giants and the smallest brown dwarfs a bit fuzzy? https://en.wikipedia.org/wiki/Substellar_object

bluGill

I wonder if this thing in turn has something in orbit around it? At the size I wouldn't surprise me if it had satellites of its own in orbit, leaving open the question of what to call them. (I'm no astrophysicist, is this really possible I don't know, but it wouldn't surprise me. What would surprise me is if we could detect them)

delta_p_delta_x

Worth noting that the artist's impression is... not accurate. Both CD-35 2722 b (the brown dwarf orbiting the primary star) and CD-35 2722 b I (the exomoon orbiting the secondary) should be much closer in size. It is estimated that Jupiter is essentially the largest any gas giant can get; adding more mass will simply increase density and interior temperature until deuterium and lithium fusion and brown dwarfdom, and then at around 80 Jupiter masses, protium fusion and stardom. Look at Barnard's Star[1], which is actually a fusing red dwarf star: it is not much bigger than Jupiter. [1]: https://en.wikipedia.org/wiki/Barnard%27s_Star

PowerElectronix

I really wanna call it a planet. It doesn't orbit a proper star, but if we call similar objects that don't orbit a star at all rogue planets I don't see why not call it just a planet.

_joel

Brown dwarfs fascinate me, they can be at room temperature (range from about 2,800 K down to 250 K (roughly 2,500 °C to -23 °C / 4,500 °F to -10 °F) You could basically have a bath in a brown dwarf, sure you might not last long, but still...

astrolx

Nice result, but I find they are selling it a bit too much. I'd rather call it an exoplanet (orbiting a brown dwarf orbiting a star).

replatformradar

About time!, I cant wait till we start putting large hardware on the dark side of the moon. That will make JST look like a toy.

codeddesign

Outside of the small probability that this may assist us in the future, has looking beyond our moon ever benefitted or even affected humanity in any way?

ck2

Literally not a moon, that headline is ridiculous (not posters fault) but Nancy Grace Roman Space Telescope WILL find Earth-sized exoplanets and even REAL moons I am stupid-excited to see it launched/first-light in my remaining lifetime (Musk better not screw it up) For perspective on the technology, JWST "only" has 28mbps downlink NGR has 500mbps downlink , that's right 1.5 TERABYTES PER DAY download speed all from ONE MILLION MILES AWAY in L2 (11 seconds ping time!) Technology is getting amazing!

WhitneyLand

Cool worlds says no? https://youtube.com/shorts/qreL7htXp98?is=G9zJVbpMT0yZsLQ-

benmoose

David Kipling has a very good short video about this announcement: https://youtu.be/qreL7htXp98?si=vBmxwW87igExZz8l (tl;dw it's an exciting discovery but moon is the wrong terminology for what was found)