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[TD1]

*colonists* "we're penetrating her outer layers now, prepare to eject from the spacecraft!"

[Starver]

*colonists* "we're penetrating her outer layers now, prepare to eject from the spacecraft!"

Only one of them will ever get to colonise, though.

[Kagus]

*colonists* "we're penetrating her outer layers now, prepare to eject from the spacecraft!"

Only one of them will ever get to colonise, though.

And, contrary to propaganda, it's not the first one in.

[TD1]

And just like that I regret my life decisions.

[Hanslanda]

And just like that I regret my life decisions.

Regret nothing

[wierd]

Wait until you get the child support bill for an entire planet's population, daddy.

[Hanslanda]

That's when you duck out of this solar system and crash on your cousin's couch in Proxima Centauri.

[Kagus]

https://amp.theguardian.com/science/2018/dec/10/tread-softly-because-you-tread-on-23bn-tonnes-of-micro-organisms

Okay, so... This is pretty big. I mean, one thing is effectively finding an entirely new biome of life here on earth, with survival methods we haven't really observed before... But just think of the implications this has for finding life on other planets.

We've more or less always based "habitability" of a planet on its surface conditions, but subterranean ecosystems that don't really care so much about surface water, winds, daylight cycles and such? That massively expands the number of viable planets.

Imagine finding subterranean microorganisms in one of our own solar system's planets, and realizing that they'd been there the whole time, effectively right under our noses.

[TD1]

I was quite surprised to see their age.

Millennia? Flippin' 'ell.

[Mech#4]

Here's some good news on the dementia research front by scientists in Brisbane, Queensland. We've got some good work being done there, Australia.

[Telgin]

That is promising looking, so hopefully the results are generalizable to humans.  Oftentimes they aren't, so hopeful skepticism here for now.

Still, this is one of those things I fear most might happen to me in later life, so I'm always glad to see progress on this front.

[TD1]

That is promising looking, so hopefully the results are generalizable to humans.  Oftentimes they aren't, so hopeful skepticism here for now.

Still, this is one of those things I fear most might happen to me in later life, so I'm always glad to see progress on this front.

Seconded.

[redwallzyl]

https://www.quantamagazine.org/what-a-newfound-kingdom-means-for-the-tree-of-life-20181211/

hemimastigote, a whole new branch of life.

[Madman198237]

Per rather lengthy derail on Ameripol (More science conversations start there and then move to here than start here, it feels like...)

Specific energy of any elliptical (i.e., bound, in-orbit as opposed to "just passing through" on a parabolic or hyperbolic orbit) orbit (energy divided by mass/independent of the mass of the orbiting body)
Epsilon is the specific energy, "a" is the semimajor axis, G is the gravitational constant.

Epsilon = -G*m_parent/(2*a) = v²/2 - G*m_parent/r

G * m_parent is usually rewritten as a constant, applicable only when the orbiting body's mass m_child << m_parent, and this constant is called "mu", so the equation gets a little neater and becomes:

Epsilon = -mu/(2*a) = v²/2 - mu/r

If you really want a derivation, Trekkin, I refer you to any intro-level orbital mechanics textbook, or possibly Wikipedia.

Oh hey look here it is yes I know, Wikipedia, but the equation is accurate.

EDIT: Taking another look the Wikipedia one does in fact use slightly different definitions for some terms, but it's right in the general specifics and both are accurate when referring to anything humans could conceivably build in the next fifty years or more.

[Trekkin]

Per rather lengthy derail on Ameripol (More science conversations start there and then move to here than start here, it feels like...)

Specific energy of any elliptical (i.e., bound, in-orbit as opposed to "just passing through" on a parabolic or hyperbolic orbit) orbit (energy divided by mass/independent of the mass of the orbiting body)
Epsilon is the specific energy, "a" is the semimajor axis, G is the gravitational constant.

Epsilon = -G*m_parent/(2*a) = v²/2 - G*m_parent/r

G * m_parent is usually rewritten as a constant, applicable only when the orbiting body's mass m_child << m_parent, and this constant is called "mu", so the equation gets a little neater and becomes:

Epsilon = -mu/(2*a) = v²/2 - mu/r

If you really want a derivation, Trekkin, I refer you to any intro-level orbital mechanics textbook, or possibly Wikipedia.

Oh hey look here it is yes I know, Wikipedia, but the equation is accurate.

EDIT: Taking another look the Wikipedia one does in fact use slightly different definitions for some terms, but it's right in the general specifics and both are accurate when referring to anything humans could conceivably build in the next fifty years or more.

Oh, I didn't want a derivation; I was mostly curious to see what you'd do when asked to put up or shut up.

You'd have had better luck using Kepler's third law, you know. Specific orbital energy's deliberately written to be, well,

independent of the mass of the orbiting body

so it's not quite germane to your point that orbit will change by changing mass, and furthermore, as you point out, we're not likely to build anything that's going to violate the underlying assumption that satellites are much smaller than the bodies they orbit anyway.

Good try, though. It's remarkable that you'd put forth the effort in the first place.