Scientists estimate that GJ3470b is losing up to 10 billion grams of material every second
What's that in sheep? I can't visualise 10 billion grams...
Somewhere in the Cancer constellation lies a mini-Neptune sized planet that is disappearing at rate faster than ever seen before, according to research published in Astronomy & Astrophysics on Thursday. The exoplanet, known as GJ3470b, is located about 97 light years away. It’s a rare find as most exoplanets are either big and …
Yep 10,000 tons a second - which the article implies is incredibly fast.
BUT... the line before says
For other types of exoplanets like hot Jupiters, which also orbit close to its host stars, the rate of evaporation can be as high as thousands of tons per second but the impact is much smaller.
So, is 10,000 tonnes a second a little or a lot?
It's very bad practice to mix units in an article.
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So, is 10,000 tonnes a second a little or a lot?
Yes.
For comparison, the Earth is about 6E21 tonnes, which at a rate of 10kton/sec would be gone in 6E17 seconds, 1.67E14 hours, 19E9 years. Slow enough to not bother me.
"For comparison, the Earth is about 6E21 tonnes, which at a rate of 10kton/sec would be gone in 6E17 seconds, 1.67E14 hours, 19E9 years. Slow enough to not bother me."
Now do the same for the mass of the atmosphere, leaving the rocky bit out of it. Is it a bit more of a worry now? :-)
Wales is for area, not volume and why bring sheep into it at all? That's just wrong! In proper El Reg units of measure, that's about 2381 KiloJubs and in improper El Reg units of measure, 1149441 Adult Badgers, 11231 Great White Sharks, 6667 Skateboarding Rhinoceri or 222 Austrailian Trams, give or take.
REF: https://www.theregister.co.uk/Design/page/reg-standards-converter.html
I've got a different problem with that : who on Earth decided that is it a good idea to use the gram to express exoplanetary loss of mass ?
We're talking about a planet that is light-years away, losing copious amounts of mass, and you deliberately choose the smallest unit of mass we have to express it ?
Saying ten thousand tons of mass per second wasn't impressive enough ?
They are Americans, they are catching onto the metric system gradually so one day will switch from cgs to mks.
Astronomy is still very cgs, since the numbers are all so unimaginable an extra 3 in the exponent doesn't make a lot of difference and it's not like you can relate any of them to normal quantities.
"These planets are difficult to study as they can only be viewed via ultraviolet light. The researchers hope to continue observing GJ347b using Hubble and eventually the James Webb Telescope..."
If they can only be observed via ultraviolet light then the James Webb Space Telescope won't be able to see them because its sensors will only operate in the Red to mid-infrared range and because it's going to be located at the Sun-Earth L2 point there won't be any possibility of adding a UV detection capability in the foreseeable future. Furthermore, I suspect that the gold-plated mirror is not suitable for UV observation.
So how exactly will the planet continue to evaporate once it lost all its atmosphere - is its sun going to start chipping away at rock then? Or is it a completely gaseous planet (in which case what exactly delimits its "atmosphere")...? And how can we even possibly know it's shrinking, considering that based on its expected billion-year lifespan and the history of our ability to detect exoplanets being measured in mere years it's hard to imagine we could possibly have detected any directly measurable change in its size...? Is this a theoretical inference only, based on the circumstances we expect the exoplanet to exist in...?
Our current understanding of low density planets is that they're a *lot* of gas around a smallish rocky core, though at Jupiter-ish sizes there's likely some crazy pressure-related shit going on with metallic, liquid, hydrogen. This one isn't anywhere near to Jupiter scales so it's probably just rocks.
So it's losing all the gas and as the article states it'll eventually end up with just the rocky core.
Sorry but that excuse is objectively wrong. The article clearly says "in only a few billion years from now, half of the planet may be gone". Not the atmosphere. The planet. I continue to consider my question valid, and apparently eight people didn't read the article.