observantTrapezium
@observantTrapezium@lemmy.ca
- Comment on The Mighty Hummingbird 2 weeks ago:
Not sure this statement is true if “more closely related” is understood as shorter combined time between the two species from their most recent common ancestor. Hummingbirds and brachiosaurs had a more recent common ancestor than brachiosaurs and triceratopses (albeit probably still quite close to the dawn of dinosaurs in the Late Triassic ), but the latter pair lived closer in time to the common ancestor of all dinosaurs (while hummingbirds are from the Oligocene).
- Comment on Still Plenty of Strange New Worlds for Star Trek to Explore: Interview with Bob Picardo 2 weeks ago:
Yeah, Paikin is a great interviewer!
- Comment on Still Plenty of Strange New Worlds for Star Trek to Explore: Interview with Bob Picardo 2 weeks ago:
I saw it a couple of days ago and thought of posting it but that nobody at a Star Trek community would be too interested in a TVO interview, and nobody in the Ontario community would be overly interested in a Robert Picardo interview. Glad there’s an overlap!
- Comment on Seconds 2 months ago:
That may be relativists (they would actually measure anything in units of mass, with everything else defined through G = c = 1). Astrophysicists commonly measure mass in solar masses, long distances in parsec (or kiloparsec, megaparsec), short distances in solar radii or AU, and time in whatever is relevant to their problem (could be seconds or gigayears)
- Comment on What's your favourite Star Trek theme? 2 months ago:
My top intro music shows: TNG, VOY, DS9, DIS, SNW, LD Honorable mention: ENT Top movie theme: First Contact
- Comment on Why does trump try to alienate black voters than expect them to vote for the dickhead? And why use Kamala's race as even a talking point let alone even a thought? 2 months ago:
Playing 4D chess /s
- Comment on Supein sama 2 months ago:
Rumania probability the closest to the country’s native name.
- Comment on perspective 2 months ago:
EM and gravitational waves are seen as analogous because as I wrote, they are produced by acceleration of charges and masses, respectively. The physics behind them is very different (described by Maxwell’s equations for EM and Einstein field equations for GW), but all systems that have waves in them (including sound in the air, waves on the surface of water etc.) can be approximated as linear for small perturbations, which means that they satisfy the wave equation at that regime.
- Comment on perspective 3 months ago:
They are quite similar to electromagnetic waves, but also quite different. They are produced by masses accelerating (just like EM waves are produced by charges accelerating), and indeed cause orbital decay. But this orbital decay is only important in relativistic systems (so the Earth, which is orbiting the sun at 0.0001 the speed of light, is not going to fall into the sun because of gravitational waves).
- Comment on perspective 3 months ago:
See my response below to Captain Aggravated about how dilute those large stars are.
It’s an interesting question whether anybody would actually feel spaghettification 😁 I actually don’t know. You can use physics to calculate the proper time derivative of the tidal forces, but you need biology to define the start (and end…) of the process. My intuition says that it probably happens too fast, so once the tidal forces are strong enough to be perceptible, they grow strong enough to rip you apart before you realize (again, just a hunch).
- Comment on perspective 3 months ago:
Yes, but red supergiants differ from the sun in that their photospheres are extremely dilute and don’t have a sharp transition to the corona. I don’t know the details of this particular star but take Betelgeuse as an example (it’s probably not particularly large for this catrgory), it’s radius is ~640 the sun’s per Wikipedia, which gives a volume of ~260 million that of the sun. But it is only x15 times as massive as the sun, so on average ~20 million times less dense.
- Comment on perspective 3 months ago:
Yep, you got it right. The accretion disk is actually really flat. Those images are produced in simulations that take into account the curved (and very complex) paths light takes in the vicinity of a black hole. These images really depend on the angle between the line of sight and the disk.
- Comment on perspective 3 months ago:
In the case you are unlucky enough to encounter the black hole “heads on” and fall into it radially, the proper time timescale to spaghettification is the size of the event horizon divided by the speed of light. The most supermassive black holes will have a horizon of around one light day, so that’s what we’re working with, a matter of days. If you come in on the most tangential orbit possible though, I guess you’re buying some time but I’ve never heard that it’s supposed to take many years of proper time (I doubt that claim a little bit, but haven’t calculated myself).
- Comment on perspective 3 months ago:
Astrophysicist here. Yes, space is crazy, but interesting things to keep in mind:
- The size of a star is determined by something called the photosphere. With those extremely massive stars, you can be hundreds of millions of kilometres “inside” and not yet know it.
- Similar story with supermassive black holes, from the perspective of an astronaut falling in, they wouldn’t really be able to tell when they cross the horizon because the tidal forces there are very small (they will inevitably fall towards the centre and get spaghettified at some point)
- Comment on Epoch fail!!! 3 months ago:
Haha, that’s right. Immediate noticed that.
- Comment on What has he done to deserve this? 3 months ago:
I think younger people in Canada only know °F if their thermostat is set to it and they can’t or don’t bother to change. My stupid fridge is in Fahrenheit and that can’t be changed (even though the handbook shows the display in Celsius! A variation of the model is probably sold abroad).
I think Canada properly adopted Celsius, kilometres, litres and millilitres (at least here in Toronto), but all other metric units are the underdog. Even CBC, that is probably the only media outlet that tries to stick to metric will specify people’s height in feet and inches. Shameful.
- Comment on Anon visits Canada 3 months ago:
He got at least partially Canadianized mid post switching from miles to kilometres.
- Comment on Children is bugs 4 months ago:
Wife should have Googled it, she’s the buttface.
- Comment on Anon earns a nickname 4 months ago:
It’s a paraphrased quote from a TV show
- Comment on Anon earns a nickname 4 months ago:
2% milk is just water that is lying about being milk.
- Comment on Irrational 5 months ago:
The premise here is completely wrong.
- Comment on Socrates 5 months ago:
A guy came from the future, using time travel technology, and the achievement he touts is simply going to the moon?
- Comment on Star Trek: Prodigy Season 2 Beams to Netflix on July 1 5 months ago:
Where there’s a will, there’s a way 🇨🇦☠️🇨🇦
- Comment on Why Detmer & Owosekun Were Missing From Star Trek: Discovery Season 5 Explained By Showrunner 5 months ago:
These two had the misfortune of being in the grey zone between background and supporting characters. It’s fine for a show not to focus on the bridge crew (who’s at the helm on the Cerritos?) but Detmer and Owosekun got a raw deal because sometimes it seemed like they were gonna have some character development. Like in season 3 that Detmer had this bizarre beef with Stamets out of nowhere, and that was probably the only episode where she got more than a couple of lines.
I’m not surprised that the actresses chose their other projects (they were probably at the bottom of the totem poll of the show in terms of pay).
I probably wouldn’t have noticed they were missing, but in episode 3 Michael introduced Rayner to the crew and said “You’ll meet Owosekun, Detmer and the rest of the crew in a little bit”, and then later Tilly said “I’ll send Commander Owosekun in”, out of screen of course. Lame.
- Comment on Star Trek: Discovery Beats Picard & Rises Higher In Nielsen Streaming Top 10 5 months ago:
Discovery got even worse after season 2.
- Comment on Learn long and prosper: U of T’s Fisher Library becomes ‘eternal archive’ on Star Trek: Discovery 5 months ago:
On behalf of UofT, what an honour /s
It caught me by surprise. When they filmed the short trek some years ago there was a university-wide email about filming going on, but this time nothing.
Both DSC and SNW are filmed in Toronto, and we’ve seen landmarks from the city before (e.g. Aga Khan Museum, Ontario Place); and of course “Tomorrow and Tomorrow and Tomorrow” took place entirely in the city in the 2020s and featured it heavily.
- Comment on How is the hydrogen made? 7 months ago:
Hydrogen was made approximately 400,000 after the big bang in a process called recombination, as the universe cooled down enough for stable neutral atoms to exist.
- Comment on Anon is a physicist 7 months ago:
Not really always, because of buoyancy. A balloon of volume V displaces the same amount of air weather it’s filled with air or lead, but in the former case the force is significant.
- Comment on \_🫨_/ 7 months ago:
Egyptian hieroglyphs used to be painted, what we see now is usually (but not always) completely faded.
- Submitted 7 months ago to startrek@startrek.website | 8 comments