An Einstein ring is an example of strong gravitational lensing,” explained study lead Conor O’Riordan of the Max Planck Institute for Astrophysics in Germany. “All strong lenses are special, because they’re so rare, and they’re incredibly useful scientifically. This one is particularly special because it’s so close to Earth and the alignment makes it very beautiful.”
I would never pretend I can even remotely wrap my head around this, but anything that helps us understand how gravity works seems like a scientific gold mine.
The precise mechanism is beyond me, but suffice it to say that light is affected by gravity.
If you imagine throwing a ball in space in a straight line near a massive body (like a planet), the ball will curve and its new straight path will now be permanently deviated from its original straight line.
Now imagine instead of throwing a ball, you’re emitting rays of light in all directions near a black hole. Light you emit towards the black hole will be lost to it, but light you emitted at an angle to the black hole will swing around it, just like the ball. If you imagine all the light you emitted slightly to the right, left, up, and down doing this, you can imagine that an observer on the other side could see all that light, appearing as though you were slightly right, left, up, and down from the black hole at the same time. This is what creates the ring.
You know how telescopes often use glass lenses to bend light into your eye? A gravitational lens is just a naturally occurring telescope, except that the gravity of a large object is the one bending the light towards us. From what I understand, an Einstein lens is just a gravitational lens where the elements for the lens sit in a particularly good setup.
But people are still shilling for starlink. I was always downvoted for mentioning the kessler syndrome or light pollution. All for progress, I guess we really need that fast internet in the middle of the atlantic.
People down voting you for bringing up Kessler syndrome were correct to do so. It’s a complete non-issue for starlink-sized objects at that altitude.
Light pollution is a more reasonable objection, and the effects on the upper atmosphere of all those satellites burning up would be as well, but not Kessler syndrome
It’s a complete non-issue for starlink-sized objects at that altitude.
Yeah. The mass and altitude are too low.
The thing with Kessler Syndrome is that collisions create debris, which cascades with more collisions, until there’s too much debris. But each collision actually results in the loss of kinetic energy or gravitational potential energy overall, so that the subsequent pieces are less energetic and/or less massive. Start with enough mass and enough altitude, and you’ve got a real problem where it can cascade many, many times. But with smaller objects at low altitude, and there’s just not enough energy to cause a runaway reaction.
Fellow dark sky supporter. Between all the led billboards, sprawl, and all the attempts at education failing… I doubt our children will have any view of the stars at all.
Unless there’s a hurricane that’s wipes out power… Stargazing was excellent for a few nights then.
Apparent scale is inverse linear, i.e., proportional to 1 / distance. If we want the apparent scale of two objects to be about 90% accurate to their actual relative scale, their relative distances to the camera can’t be more than 10% different. Pluto being 40-ish astronomical from Earth, you’d want to shoot from about 400 AU. Voyager I should be in prime position circa 2140.
I drove 2200 miles for this solar eclipse. I booked a place here in Dallas last year, and now it seems like it’s going to be cloudy with rain and thunder. :-/
I convinced my dad to fly over and join the road trip.
At least we got to see some incredible stuff on the way! Maybe there will be a break in the clouds…
I was in the same boat, 2000+ mile drive. NE Texas isn’t looking too bad right now! But if you’re up to it, drive up to Arkansas. I did that today from Austin-ish. Clouds up here are looking much more optimistic!
I’ve heard that it’s still a surreal experience even when overcast. Though, that’s what I had to believe to actually book the hotel room and days off work as somene living on the north-atlantic coast.
I was able to see the one back in 2017 smack dab in the middle of the path of totality and it was such a surreal otherworldly experience. No amount of trying to explain it to other people helped them really understand. Things look a weird way and there’s a very unique feel to it all.
My advice, get things set up, get your shots, start your recordings, but don’t forget to take 30seconds or so and just soak it in and be in the moment!
The abundance of back-to-back solar events has led scientists to think the sun may have entered its explosive era of peak activity, known as solar maximum — which seems to be starting a year earlier than previous forecasts predicted. However, researchers will have to wait until the sun “calms down” to know for sure.
What we do know is that X-class flares are most common during solar maximum, which is part of the sun’s 11-year solar cycle. So far in 2024, seven X-class flares, including the latest one, have burst from the sun, which is already half the number that reached Earth in 2023, Live Science previously reported.
On a long enough timescale, we’re gonna be hit by a big one.
I remember like a decade ago they were saying it hits a developed area, it’ll blow out all the transformers, and on that scale no country could replace them all for a very long time.
I agree. There were articles and documentaries about 20 years ago that I remember featuring these sort of events. The continent affected would take 20-30 years to rebuild its electricity grid.
I’ll just never get over how “we” (science I guess) know that stuff like this isn’t a question of if, but when.
And we just don’t seem to get ready for it.
Like, Y2K we saw coming and everyone handled it in time. But if there’s no firm date on something, everyone with the power to do anything just ignores it.
As a society it just feels like we’re living paycheck to paycheck. Can’t worry about next year cuz rents due in two weeks shit.
In general, people are appallingly bad at weighing up long-term vs short-term stuff, both in terms of risks and benefits. It's even worse when, as you say, there's no definite deadline or it doesn't directly affect those who can do something about it.
What you didn’t see was the guy who made the problem in the 60s warn everyone about it from the 70s onward until his retirement in the 90s, then everyone say oh shit, he is right.
The Carrington event was a big one. It is estimated to have been an X40 flare. This article is about an X1.1 flare. Telegraph poles caught fire. The auroras were so bright people woke up and started making breakfast even though it was the middle of the night. They were visible as far south as central Mexico! If we got hit by a Carrington scale flare today we would be repairing the power grid for the next half century.
I believe it’s possible to avoid if the proper protocols are in place. Namely, the grid has to be turned off completely before the flare hits and then things will mostly be fine. Just wonder how well we can predict these events.
My understanding is that we actually don't have much of a warning (under an hour), since a CME has to reach the satellite at the Lagrange point between Earth and the Sun for us to know it's about to hit Earth. According to the article below, this includes power companies, but I remain skeptical that there's enough organisation in place to shut down the North American, European or Asian grids in 15 minutes.
“Either extraterrestrial civilizations (ETCs) are incredibly rare (or non-existent), or they are deliberately avoiding contact with us (aka. the “Zoo Hypothesis“).”
There is a 3rd possibility - it may not be deliberate.
Our position in the Milky Way is really out on the ass-end of it. We are nowhere near galactic central. If our current understanding of slower than light travel is correct, it just may not be possible for other civilizations to reach us.
When it comes to communications, and our radio sweeps of the galaxy turning up nothing, well, we’re assuming any advanced civilization is still using radio transmissions.
Look at our recent experiment with laser based communication:
100 or so years after radio communication was widespread, we have the technology to eliminate it. There may be other methods orders of magnitude beyond that. We could be awash in alien communication streams we just can’t percieve because ours are too primitive.
There are also hundreds of other theories that can potentially explain it. Like, 100 years really isn’t a long time on cosmic scales. Maybe we’re late to the party and intelligent life wiped itself out already. Maybe we’re early, and we will wipe ourselves out before a new intelligence even figures out where the copy paper is.
We don’t want to be near the galactic center, there’s too much radiation. A quiet spot out on one of the arms away from supernovae and active objects is a much better place for life to evolve.
At this point our own radio is even too advanced for an alien civilization to detect. An interesting thing about radio is that aside from a few lingering powerful analog signals (AM/FM radio, active radar) our modern spread-spectrum radio is hard to distinguish from background noise. It’s an interesting consequence of information theory, as bandwidth and noise tolerance grow, if you aren’t looking for a signal it becomes almost invisible. We also do a lot with very little power now due to these amazing encoding methods, when I was a kid and the analog cell phone was novel we would have outright said that a phone could never communicate directly with satellites. Not enough power or antenna in your pocket. Yet here we are.
So any civilization that develops radio is only likely to send out a short burst of detectable radio before disappearing within 100 years, even without switching to an alternate technology. This makes radio an almost impossible thing to search for in a vast galaxy where time can separate us even more than space.
But if NASA 'can’t do anything right,' how come SpaceX and other private companies like stylo rely so heavily on former NASA engineers, research, and infrastructure to even operate?
One of the things they’re doing is calculating what it’s orbit would have to be to hit the Earth, and where it would have had to have been on its last orbit to be in that orbit
So they can look at any astronomical images of that part of the sky from then and see if it’s in the right place
If they find images of the right part of the sky at the right time and the asteroid is not in it, they know it’s not on an orbit that will hit the Earth in 2032
I science podcast I follow already warned last week that the probability would go up at first as they narrow down its trajectory.
They gave the example of a fan closing, as it gets narrow, the earth represents a bigger percentage of the remaining fan. If you keep closing the fan the Earth eventually will fall outside the fan and the percentage drop to zero.
Ok, so: you know how Earth is part of the solar system? And the solar system is part of a large collection of stars and planets called a galaxy?
Well, there’s lots of galaxies out there! And scientists for a long time have been trying to figure out how they formed - how did all the stars get close to each other? Why aren’t they just randomly drifting around?
Currently, everyone believes that there’s this magic stuff called “dark matter” that pulled the stars together to make galaxies. Kinda like how magnets pull things close to them!
And because galaxies are so big it would take a long time to pull the stars close together! Which means young galaxies would look less bright because the stars aren’t all close together yet, like they are with older galaxies.
So that’s what everyone believes.
But we’re getting pictures from a really strong telescope that’s showing us that young galaxies are brighter than we expected! Which is weird and exciting because it means that young galaxies might have been pulled together faster than we used to think! And our old theories about galaxy creation might be wrong!
There’s a theory that explains how galaxies could come together quickly, without dark matter, but it doesn’t really fit with many other theories we have about how the world works, so lots of people are thinking really hard to figure out how they might fit together.
And that’s what science is all about! Finding out new information that shows you that you were wrong in the past, and using that information to figure out new ways to act and think in the future!
Nope. No. Nuh-uh. Stop fucking up this planet, then we can talk. I’m drawing a line in the sand, I’m going to become an eco-terrorist if I see a fucking Coca-Cola ad when I look into the night sky.
All I think of is the movie, The Time Machine. Spoiler, the main character goes forward in time and sees the moon breaking apart, causing a collapse of civilisation.
astronomy
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