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edgemaster72, w Asteroid 2024 YR4 now has a 1.94% chance to hit the Moon (according to my own calculations)
@edgemaster72@lemmy.world avatar

Nooo not the moon, it didn’t do nothing to no one. Come back YR4, we still have some lovely cities you could obliterate.

conditional_soup, w Asteroid 2024 YR4 now has a 1.94% chance to hit the Moon (according to my own calculations)

This is super cool! I was kinda hoping it would hit soonish. 2032 feels like it might as well be 3032 with how things are going. Hopefully this doesn’t mess up any of the world’s plans for lunar bases.

magnetosphere, w Confirmed at Last: Barnard's Star Hosts Four Tiny Planets
@magnetosphere@fedia.io avatar

Read the source as “assnova.com”

mysticpickle,

Some asses are so THICC they just collapse into themselves in an explosion of seductive destruction that can be seen light years away

egrets, w Confirmed at Last: Barnard's Star Hosts Four Tiny Planets
@egrets@lemmy.world avatar

Unfortunately we’ll never get to visit them in person if Prostetnic Vogon Jeltz has anything to say about it:

We are about to jump into hyperspace for the journey to Barnard’s Star. On arrival we will stay in dock for a seventy-two-hour refit, and no one’s to leave the ship during that time. I repeat, all planet leave is canceled. I’ve just had an unhappy love affair, so I don’t see why anybody else should have a good time.

FundMECFSResearch, w Confirmed at Last: Barnard's Star Hosts Four Tiny Planets

Just 6 light-years away, Barnard’s Star is a well-studied 10-billion-year-old M dwarf with a mass of 0.16 solar mass. Finding exoplanets around Barnard’s Star has been something of a white whale for astronomers for more than half a century; starting in the 1960s, researchers have claimed to have spotted various planets around Barnard’s Star, from distant Jupiter-mass companions to close-in super-Earths. Each of these claims has been refuted.

Now, the white whale appears to have been caught at last. Just last November, researchers reported the discovery of a planet orbiting Barnard’s Star with a period of 3.154 days. The data hinted at the presence of three other planets, but these candidates could not be confirmed. In a new research article published today, Ritvik Basant (University of Chicago) and collaborators leveraged years of data to confirm that Barnard’s Star hosts not just one, but four planets.

SplashJackson,

Good summary, but to everyone else reading this, it’s really worth it to read the article. It’s short and yet, frankly, fascinating. It discusses the methods used to identify the exoplanets and their orbital periods.

RizzRustbolt, w Confirmed at Last: Barnard's Star Hosts Four Tiny Planets

And we’ve made our first step towards the Time Tombs.

Wahots,
@Wahots@pawb.social avatar

Late stage Kassad needs to get his ass to Earth, we need him.

janus2, w Saturn has 128 new moons – more than the rest of the planets combined
@janus2@lemmy.zip avatar

“Did you bring enough to share with the whole class?”

the class:

pennomi, w Confirmed at Last: Barnard's Star Hosts Four Tiny Planets

These planets are in remarkably close quarters, with periods of just 2.34, 3.15, 4.12, and 6.74 days.

Speedy little guys

very_well_lost,

The furthest of the four is estimated to have an orbital radius of about 0.03 AU. That’s 1/10th the size of Mercury’s orbit around the sun!

veroxii,

At least it’s a dry heat.

keepthepace,

850°C apparent temperature 830°C. Stay hydrated.

muhyb,

That’s a fuel scooping range.

Wahots,
@Wahots@pawb.social avatar

Warning, temperature critical.

keepthepace,

“Hot planets are waiting for you in the star’s neighborhood!”

haroldfinch, w Confirmed at Last: Barnard's Star Hosts Four Tiny Planets

Wonderful confirmation.

To think how hard it is to confirm these planets, for such a relatively close star. When we have already confirmed so much about objects at far greater distances.

Hard to comprehend these achievements from our individual perspectives. 👏

Rhaedas,
@Rhaedas@fedia.io avatar

I wonder if Kepler or others would have found these planets had Barnard's Star been in the areas searched? I.e., very small planets in close orbits around a dim star is a very difficult target, period. This also means that the thousands of systems we now know about certainly have far more than the few bodies we've detected because we can only see the biggest ones well.

Potatisen, w Asteroid 2024 YR4 now has a 1.94% chance to hit the Moon (according to my own calculations)

Wooow, this is super cool!

As someone who doesn’t know or understand any of this math/physics. Would you mind doing a super simple explanation of how the calculation works and why you chose certain factors?

Might be a dumb thing to ask but just curious and want to understand more.

LostXOR, (edited )

Sure thing!

D_nominal, D_min, and D_max represent the most likely, minimum, and maximum (well technically not maximum, just 3 standard deviations from most likely, of which 99.7% of trajectories will fall within) distance 2024 YR4 will pass from the center of the Moon (NOT the surface). They're taken from the linked NASA website. R_moon is the radius of the Moon.

L_impact is length of the impact corridor (the line where 2024 YR4 could impact the Moon). Since it doesn't pass through the center of the Moon, it's not simply 2*R_moon and so we need a simple formula to calculate it from R_moon and D_min.

P(x) is a probability density function; it's the black curve you can see. It shows, for a given trajectory along the line of possible trajectories, how likely 2024 YR4 is to follow that trajectory. It's shifted a bit from the center since the most likely trajectories are not exactly centered on the Moon. P_impact is the area of P(x) that falls within +/- L_impact, AKA the probability that the trajectory will intersect the Moon, AKA the impact probability.

The rest is just some graphing stuff that doesn't matter to the calculation.

keepthepace,

AKA the probability that the trajectory will intersect the Moon, AKA the impact probability.

(Disclaimer, I know close to nothing about these) Am I pedantic about a useless detail or does it significantly change the probability if we consider that an object may still impact the moon after “missing it” if it comes close enough to be captured and come back after a semi orbit? Or do the relative speeds makes this extremely unlikely?

LostXOR,

It's going far too fast to be gravitationally captured.

Potatisen,

Cool! Thanks for the explanation.

otter, w Saturn has 128 new moons – more than the rest of the planets combined

Slut.

Try not to grab another moon on your way through the parking lot!

Bristingr, w Saturn has 128 new moons – more than the rest of the planets combined

What, having the best rings wasn’t good enough for Saturn? Gosh, how greedy. /s

Zzyzx, w Saturn has 128 new moons – more than the rest of the planets combined

Jupiter excitedly pointing out this news to Juno

pwnicholson, w Saturn has 128 new moons – more than the rest of the planets combined
@pwnicholson@lemmy.world avatar

*“Newly identified moons” I’m pretty sure they’ve been there for a while.

Having 128 new moons would really be noteworthy!

troyunrau, w Saturn has 128 new moons – more than the rest of the planets combined
@troyunrau@lemmy.ca avatar

This is a great question. It’s like asking when a rock is too small to be a planet. I suspect there were be a definition eventually that mirrors the planetary definition – something like “spherical(ish) and clears its orbit”. The issue is that Mars would lose its two moons under that definition.

So we might end up with something like “moons” vs “natural satellites” and Mars will just have to suck it up.

kinttach,

Moons vs. dwarf moons? (Sounds like a fantasy novel series.)

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