Yea, "near Milky Way" would have been better. The closest galaxy (Andromeda) is 2.5 million light-years, so 12 million to Centaurus A is pretty close. It's also the fifth brightest galaxy in the sky, so "near" in that sense too.
"In nearby galaxy" probably got canned by the editors, who as we all know from many many sessions of grumbling, often pick the titles without much input from the author.
12 million light years is near to Earth, as galaxies go. The overwhelming majority of the hundreds of billions of other galaxies are hundreds to thousands of times farther away.
Heh, well some familiarity with cosmology is assumed. All (AFAIK) supermassive blackholes are in the center of galaxies.
By my math 99.987% of the universe is further away than 12 million light years. As mentioned in the article it's so big that from earth it's 16 times larger than the moon (as viewed from earth of course).
Seems reasonable to consider 0.012% of the universe "near earth" when talking about galaxies or blackholes at the center of a galaxy.
More probably it ate thousands if not millions of stars.
It would be tricky to get it to swallow a star so big before that went supernova, while on the way in, on its own initiative. Whether the resulting black hole would then be swallowed up, or also be flung out at near light-speed with the rest of the ejecta, is an interesting question.
> The emission is powered by a central black hole in the galaxy Centaurus A, about 12 million light years away.
> As the black hole feeds on in-falling gas, it ejects material at near light-speed, causing ‘radio bubbles’ to grow over hundreds of millions of years.
> Is that a coincidence, or did this SMBH eat one of those enormous stars that's the diameter of Venus' orbit?
au contraire, enormous (in terms of mass not volume) but dying Neutron stars are so compressed under their own gravity, some are barely 12 to 25 kilometers in diameter of highly condensed Iron and other stable atomic arrangements, and may be spinning 40,000 times per minute on their own axis. Sometimes, there are two of those in a binary system, orbiting each other, on a collision course for a Kilonova, spraying out bazillion tonnes of star and planet making substances across a Galaxy.
A blackhole gulping Neutron Stars down would make for an interesting event!
> a person that understands the topic should immediately understand we are talking about relatively close galaxy.
Sure, but a person who doesn't would receive the message more clearly if it were stated as "Supermassive black hole eruption near milky way". Otherwise I could write "Supermassive black hole eruption near New York" and be equally correct.
I suspect the potential for misunderstanding was the reason the headline was chosen in this form, however ...
I fully agree that "near the White House", "near Washington", "near Earth", "near the solar system", and "near the Milky Way" all convey strongly different ideas of what "near" actually means. However, I think in this case they were basically going for "surprisingly near", or "near us". I think it's reasonable to say that this is unusually close to us.
Well, the headline as it currently stands includes both the earth and the moon which definitely primes the thoughts.
I know research on priming has got some well deserved criticism, but there is no doubt basic framing works and this article either plays this effect for purpose or is scarily unaware of it.
Sure, but the nearest planets, stars, and galaxies to earth also gives an idea of the scale they are talking about. Sure you could say nearest the milky way, but sadly I suspect that a decent fraction of folks wouldn't not respond with "Milky Way" when asking for what galaxy the earth is in.
The purpose of the title of any article is to attract attention, so from that point you could say every title is clickbait.
Where I define "too far" (or actual clickbait) is when the title is dishonest about its contents or is purposefully omitting important information that makes the article much less interesting than the title suggests.
In this case the title was actually both truthful and contained relatively complete description of what is included in the article. Could they say "near Milky Way"? Well... they could, but "near Earth" is also factually correct.
And 12 million light years is actually quite close for any new supermassive black hole-related findings.
> Where I define "too far" (or actual clickbait) is when the title is dishonest about its contents or is purposefully omitting important information that makes the article much less interesting than the title suggests.
A lot of clickbait is technically correct including many of the dreaded "<n> <x> that <y> - you won't guess number <z>".
I suppose You could also measure such things in respect to time, considering the apparent distance of this event it also occurred long long ago in a galaxy far far away!
12 million light years is 0.013% of the size of the observable universe (93 billion light years diameter). That's quite close on a scale relative to the size of space.
> the size of the observable universe 93 billion light years diameter
While observable Universe will always be 93 billion light years in diameter, it is worth noting that everything is moving away from everything faster than gravity can counteract. That is, the Causally Disconnected (un-observable) Universe is inflating faster, the bigger it gets.
Wow! This has a size of about 1.7 million lightyears, which is nine times the size of the milky way, and nearing the distance to Andromeda which is about 2.5 million light years.
Spanning 8 degrees, 12 million light years away? That's insane. A feature that's 1.67 million light years across? That's insane. That's a sixth of the size of the entire local cluster.
As noted, 0.5° across... but this misconception is in part because 360° or even 180° is really big when you're sitting at the center of it.
I believe part of this misconception comes from that when we look at something, we're only paying attain to +/- 15° while the bifocal range is 120° and the full field of view with both eyes is about 200°. Additionally, the field of view of the photographs that involve the sun or moon are often in the 5° to 15° range.
Another aspect of the moon and its size and the sky sphere - it moves at a fairly good clip. The sun is easier to think of though, it moves through 360° is 24h. That gives 15°/h or 0.25°/m. Every two minutes, the sun moves a solar diameter across the sky the moon has a similar amount of motion over a short period of time. This makes it difficult to take long exposures of the moon without a tracking mount.
Heh, it's easy to think these days that the moon is larger than you think. Especially with so many articles showing huge detailed pictures of the moon.
Try taking a picture of the moon with a cell phone (even one with the best in the market camera) and be prepared to be disappointed.
My first experience with "well, that didn't work" was about 30 years ago. I had a 35mm point and shoot (fixed focus too) camera. I shot one roll at night trying to photograph the full moon. They didn't even cut the film. When looking at the negatives, all that you could see on a long strip of film was an occasional very small black dot.
From this, I learned two things: (1) The moon is much smaller in the sky than you think it is. (2) Take a picture of a white wall or similar thing to expose an entire frame so that additional frames can be calculated form that first (or last or both) frame and the proper cuts of the film can be made.
I've got a Pixel 6 pro, 4x optical zoom, decent sensor, and a astrophotography mode. It does take some nice sky photos, but the moon is just too small.
Cameras on phones just aren't designed for the narrow field of view that much of astrophotography uses. The thing to look up is "wide field astrophotography" - but even then, you get into issues.
While it's a little dated (digital has come a long way), if you are interested in it with a "real" camera... hunt up a copy of Heavenly Bodies: The Photographer's Guide to Astrophotography by Bert P Krages.
I wonder what the radiation environment in the galaxy is. How bright a galactic center black hole can be before the whole galaxy becomes uninhabitable by something like us.
Galaxies are hazardous places to be. E.g., a minor hiccup on a magnetar 500 ly from Earth would sterilize it. Earth, that is. One might drift into range any time; Sol has probably been that near to one for a million years at least several times, as it orbits inside the Milky Way every 200 million years.
Any civilization interested in longevity would get the hell away from any galaxy as soon as it could manage.
Now, on a more serious tone, we may want some contingency plans with underground environments and something to preserve some life for long enough we could be able to re-seed a biosphere on the surface.
Useful for ice ages too.
Now imagine it as the start of a story - we terraform Mars, or Venus, only to trigger a re-seeding of the now friendly environment by long buried machines left by a dead civilization.
Who says we haven't been making our way out for awhile now? I also like the theory that a previous civilization was all soft biology based and that its tech would leave no trace.
Speaking of underground environments, Mercury would be an excellent location.
An initial colony could be supplied by advancing multiple launches with supplies and landers before the first colonists arrive at sunset. They’ll have 88 days to assemble the underground habitats or abort and come back.
Are there any perpetually shaded areas? If so, the 88 day deadline could be extended by as much as we want just by sending supplies in advance.
And having between 4 and 10 times as much sunshine we could even generate some power from the light reflected in the crater/canyon rim.
Yes, there are craters with water ice in them that are permanently shaded near the poles. Solar concentrators could be moved out of the shadows and redirect light, generate electricity or heat.
I think we could be less than 5 years away from landing a Starship in a crater on Mercury.
The Faraday cage that can block gamma and cosmic rays masses more than the solar system.
Probably you find a pair of rogue gas giants, and set them orbiting one another out in interstellar space, arranged so one is always positioned lbetween your planet and the nearest magnetar.
It would be quite easy at the bottom of some of our deeper mineshafts. The radioactivity would never penetrate a mine some thousands of feet deep. And in a matter of weeks, sufficient improvements in dwelling space could easily be provided.
A computer could be set and programmed to accept factors from youth, health, sexual fertility, intelligence, and a cross section of necessary skills. Of course it would be absolutely vital that our top government and military men be included to foster and impart the required principles of leadership and tradition. Naturally, they would breed prodigiously, eh? There would be much time, and little to do. But, ah, with the proper breeding techniques, and a ratio of say, ten females to each male, I would guess that they could then work their way back to the present gross national product within say, twenty years.
Are the stars orbiting the Milky way all orbiting at very different speeds then? If not, I would think the stellar environment of any star would remain relatively constant over time.
Speeds (linear and angular) decrease the further we are from the center, so bodies near the center will orbit it in less time than us, who take less time to do a lap around the galaxy than stars further out.
There's some variability across different galaxies, but generally the curve is pretty flat if you're not right near the center. So the galactic year for a star at the outermost edge of our galaxy should be about the same as ours.
Stars are not, as a rule, orbiting in perfect circles. So, they are continually whizzing past one another as they trace out their respective orbits.
The orbits are not even nice ellipses. Those only happen with point or (equivalently) spherical masses. The Milky Way is a quite irregular shape, and we are orbiting inside it. Our path bobs up and down through the galactic plane as we orbit, and not just once per orbit like a planet, but over and over.
The planets like the sun that formed from the same gas cloud are long gone, stirred into the galactic soup.
When the title said "supermassive black hole eruption" instead of "Sag A* eruption" it was pretty clear the supermassive black hole was not our own supermassive black hole, but some other galaxy's. I was curious whether it could be Andromeda's SMBH flaring, but very certain it wouldn't be our own.
the relative sizes of things you have trouble seeing due to dimness or can't see due to wavelength is very wild to me, for example the andromeda galaxy (you can only, at best, see its nucleus even with a proper telescope or binoculars):
I wonder if this is an example of an amazing event in the universe or an example of the amazing improvements in observational technologies. Will this be a much more common observation in six months or so when the James Webb telescope comes online?
I normally don’t put much emphasis or thought of our space or size in the galaxy or universe. However, it is very revealing how we are very much “a pale blue dot” within perfect distance to our sun and moon, and are a very special species on an amazing planet. We are not insignificant. Indeed, we are the exact opposite.
80 comments
[ 3.4 ms ] story [ 147 ms ] threadI know it's lame to comment on the single stupid thing in an article, but this is absurd.
https://en.wikipedia.org/wiki/Centaurus_A
By my math 99.987% of the universe is further away than 12 million light years. As mentioned in the article it's so big that from earth it's 16 times larger than the moon (as viewed from earth of course).
Seems reasonable to consider 0.012% of the universe "near earth" when talking about galaxies or blackholes at the center of a galaxy.
Is that a coincidence, or did this SMBH eat one of those enormous stars that's the diameter of Venus' orbit?
It would be tricky to get it to swallow a star so big before that went supernova, while on the way in, on its own initiative. Whether the resulting black hole would then be swallowed up, or also be flung out at near light-speed with the rest of the ejecta, is an interesting question.
> As the black hole feeds on in-falling gas, it ejects material at near light-speed, causing ‘radio bubbles’ to grow over hundreds of millions of years.
au contraire, enormous (in terms of mass not volume) but dying Neutron stars are so compressed under their own gravity, some are barely 12 to 25 kilometers in diameter of highly condensed Iron and other stable atomic arrangements, and may be spinning 40,000 times per minute on their own axis. Sometimes, there are two of those in a binary system, orbiting each other, on a collision course for a Kilonova, spraying out bazillion tonnes of star and planet making substances across a Galaxy.
A blackhole gulping Neutron Stars down would make for an interesting event!
No blackhole, no jets. Seems a bit pedantic to mention that the observed jets aren't crossing the event horizon.
So a person that understands the topic should immediately understand we are talking about relatively close galaxy.
Sure, but a person who doesn't would receive the message more clearly if it were stated as "Supermassive black hole eruption near milky way". Otherwise I could write "Supermassive black hole eruption near New York" and be equally correct.
I suspect the potential for misunderstanding was the reason the headline was chosen in this form, however ...
I know research on priming has got some well deserved criticism, but there is no doubt basic framing works and this article either plays this effect for purpose or is scarily unaware of it.
That explains a lot of clickbait!
The purpose of the title of any article is to attract attention, so from that point you could say every title is clickbait.
Where I define "too far" (or actual clickbait) is when the title is dishonest about its contents or is purposefully omitting important information that makes the article much less interesting than the title suggests.
In this case the title was actually both truthful and contained relatively complete description of what is included in the article. Could they say "near Milky Way"? Well... they could, but "near Earth" is also factually correct.
And 12 million light years is actually quite close for any new supermassive black hole-related findings.
A lot of clickbait is technically correct including many of the dreaded "<n> <x> that <y> - you won't guess number <z>".
While observable Universe will always be 93 billion light years in diameter, it is worth noting that everything is moving away from everything faster than gravity can counteract. That is, the Causally Disconnected (un-observable) Universe is inflating faster, the bigger it gets.
But yes, farther out than Andromeda.
Sun, likewise, of course.
So these radio lobes reach out another moon-width from both sides of your thumb.
I believe part of this misconception comes from that when we look at something, we're only paying attain to +/- 15° while the bifocal range is 120° and the full field of view with both eyes is about 200°. Additionally, the field of view of the photographs that involve the sun or moon are often in the 5° to 15° range.
That narrow range photograph - https://www.deviantart.com/shagie/art/Crescent-Moonset-70823... and that has a 3.4° field of view on the short axis.
This is closer to the regular field of view - https://www.deviantart.com/shagie/art/Moon-and-sunset-318111... though I shot it portrait rather than landscape. That has a 27° field of view on the short axis and a 40° field of view on the long axis.
Another aspect of the moon and its size and the sky sphere - it moves at a fairly good clip. The sun is easier to think of though, it moves through 360° is 24h. That gives 15°/h or 0.25°/m. Every two minutes, the sun moves a solar diameter across the sky the moon has a similar amount of motion over a short period of time. This makes it difficult to take long exposures of the moon without a tracking mount.
Try taking a picture of the moon with a cell phone (even one with the best in the market camera) and be prepared to be disappointed.
From this, I learned two things: (1) The moon is much smaller in the sky than you think it is. (2) Take a picture of a white wall or similar thing to expose an entire frame so that additional frames can be calculated form that first (or last or both) frame and the proper cuts of the film can be made.
While it's a little dated (digital has come a long way), if you are interested in it with a "real" camera... hunt up a copy of Heavenly Bodies: The Photographer's Guide to Astrophotography by Bert P Krages.
Any civilization interested in longevity would get the hell away from any galaxy as soon as it could manage.
Now, on a more serious tone, we may want some contingency plans with underground environments and something to preserve some life for long enough we could be able to re-seed a biosphere on the surface.
Useful for ice ages too.
Now imagine it as the start of a story - we terraform Mars, or Venus, only to trigger a re-seeding of the now friendly environment by long buried machines left by a dead civilization.
Speaking of underground environments, Mercury would be an excellent location.
http://www.einstein-schrodinger.com/mercury_colony.html
Are there any perpetually shaded areas? If so, the 88 day deadline could be extended by as much as we want just by sending supplies in advance.
And having between 4 and 10 times as much sunshine we could even generate some power from the light reflected in the crater/canyon rim.
I think we could be less than 5 years away from landing a Starship in a crater on Mercury.
Probably you find a pair of rogue gas giants, and set them orbiting one another out in interstellar space, arranged so one is always positioned lbetween your planet and the nearest magnetar.
A computer could be set and programmed to accept factors from youth, health, sexual fertility, intelligence, and a cross section of necessary skills. Of course it would be absolutely vital that our top government and military men be included to foster and impart the required principles of leadership and tradition. Naturally, they would breed prodigiously, eh? There would be much time, and little to do. But, ah, with the proper breeding techniques, and a ratio of say, ten females to each male, I would guess that they could then work their way back to the present gross national product within say, twenty years.
This is one piece of evidence for the existence of dark matter.
The orbits are not even nice ellipses. Those only happen with point or (equivalently) spherical masses. The Milky Way is a quite irregular shape, and we are orbiting inside it. Our path bobs up and down through the galactic plane as we orbit, and not just once per orbit like a planet, but over and over.
The planets like the sun that formed from the same gas cloud are long gone, stirred into the galactic soup.
It’s a clickbait addition to the title by the original authors that is already causing confusion in the comments here.
The galaxy in question is 12 million light years away. That is (literally) not astronomically close.
There aren’t that many big galaxies in the radius.
https://slate.com/technology/2014/01/moon-and-andromeda-rela...
I normally don’t put much emphasis or thought of our space or size in the galaxy or universe. However, it is very revealing how we are very much “a pale blue dot” within perfect distance to our sun and moon, and are a very special species on an amazing planet. We are not insignificant. Indeed, we are the exact opposite.