2135: M87 Black Hole Size Comparison

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M87 Black Hole Size Comparison
I think Voyager 1 would be just past the event horizon, but slightly less than halfway to the bright ring.
Title text: I think Voyager 1 would be just past the event horizon, but slightly less than halfway to the bright ring.


This comic shows the picture of the M87 black hole by the Event Horizon Telescope that was published on the same day as this comic. Overlaid on the picture is a scale image of the Solar System, showing the Sun, Pluto (one of the most well-known dwarf planets) and its orbital path, and Voyager 1, a deep-space probe and the current farthest probe from Earth. The comic is quite similar to 1551: Pluto, in which Randall overlaid annotations onto the recently-released first images of Pluto taken by the New Horizons spacecraft.

The point of the comic is to celebrate the release of this image by the Event Horizon Telescope, referenced two comics earlier, in 2133: EHT Black Hole Picture, as well as to indicate the hugeness of M87 and the awe-inspiring thing that space is. This image has been widely publicized as being the first image ever of a black hole. Science had no visual evidence of black holes at all until 2012.

In the title text Randall hypothesizes that if the Sun were at the center of M87, Voyager would be outside the event horizon. This is confirmed by a 2015 study in which the Schwartzchild radius of M87* was found to be 5.9x10^-4 pc, as opposed to the distance of 7.04x10^-4 pc, at the time the comic was written, between Voyager 1 and the Sun.

The comic's scale seems to be slightly small; while the orbit of Pluto should be about 4.9 microarcseconds across, in the comic it's about 3.9 microarcseconds across.


[Caption above the panel:]
Size comparison:
The M87 Black Hole
Our Solar System
[Caption at top left of the panel:]
EHT Black Hole Image
Source: NSF
[An image of the M87 black hole captured by the event horizon telescope on the day that this comic was published is shown, in the shape of a thick red-and-yellow ring on a black background.]
[A white ring about 1/4 of the diameter of the central black portion of the image is labelled with an arrow:]
[A small white circle at the center of the image is labelled with an arrow:]
[A small white dot on the right hand edge of the central black portion of the image is labelled with an arrow:]
Voyager 1

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inb4 anti-semitic troll vandalizes the page 19:38, 10 April 2019 (UTC)

Jeez, it hasn't happened yet? --Youforgotthisthing (talk) 19:54, 10 April 2019 (UTC)
Shhh! You'll jinx it! Herobrine (talk) 21:07, 10 April 2019 (UTC)
I’m surprised. “That Guy from the Netherlands” (talk) 23:06, 10 April 2019 (UTC)
I always miss it, you guys are too fast for me to see it. Not that I want to see it of course. Linker (talk) 12:08, 11 April 2019 (UTC)
Well, we made it until 15:40 on the 11th. Since it was created at 18:50 on the 10th, that's about... 20 hours and 15 minutes. Considering how it only took 13 minutes for #2133 to be vandalized-I-mean-corrected, and 25 minutes for #2125, it seems they're getting slower! I wonder if the poor lil fellas need more attention. :( --Youforgotthisthing (talk) 00:43, 12 April 2019 (UTC)

Am I the only to one who is amazed at just how *far* Voyager has come? 19:52, 10 April 2019 (UTC)

I thought the dark disk on the photo is 2.6 Schwartzchild radii, not 1? -- 20:50, 10 April 2019 (UTC)

I Googled to get a sense of scale. Apparently the sun would be less than 4 miles across if compressed into a black hole. The magnitude is incomprehensible. 02:54, 11 April 2019 (UTC)

I believe "Voyager I" in the title text is a typo and Randall meant to say Voyager II. The location Randall notes would correspond closer to Voyager II than I(9.3 billion miles away from earth vs 11 billion miles). 06:21, 11 April 2019 (UTC)

I updated a few things in the explanation a couple hours back. It should read more smoothly now. Fmccarthy (talk) 08:01, 12 April 2019 (UTC) Rephrase scale reference 2.5 times smaller is not a good way to express reduction in size. It's clearer to say that it's two-fifths as big or it's 40% of the size. 09:58, 11 April 2019 (UTC)

It's what the official website says. Numberland (talk) 20:28, 14 April 2019 (UTC)

Is anyone agreeing with the source ? haven't found a clear attribution of the image to NSF; and also would be suprised to find one.

NSF link to image, NSF page with attribution, "The National Science Foundation (NSF) played a pivotal role in this discovery by funding individual investigators, interdisciplinary scientific teams and radio astronomy research facilities since the inception of EHT. Over the last two decades, NSF has directly funded more than $28 million in EHT research, the largest commitment of resources for the project." Source Article and NSF relation to EHT -- 16:30, 11 April 2019 (UTC)Zenthere
but in your news link, the NSF itself gives credit to EHT, so the source should be EHT for the image. Just my opinion.

This is alot like the Pluto comic from a few years back. Take The A Train To Watertown (talk) 12:10, 11 April 2019 (UTC)

Why is pluto bigger than the sun? Lekkin007 (talk)

the circle is more likely to be pluto's _orbit_, in which there is a small break, in which there is a small dot, which is more likely to represent pluto. the arrow points to the dot. ocæon (talk) 23:03, 12 April 2019 (UTC)
Lies. If it was pluto's orbit, it would say so. It clearly says Pluto. The small break is probably just a mountain or some other surface anomaly. I think that pluto is actually smaller than the sun, but it was closer to the camera, so it appears bigger. 02:05, 16 April 2019 (UTC)

I am trying to spread truth and good critical thinking, but IP editors keep reverting My well-intention edits! What can I do? 16:59, 11 April 2019 (UTC)

I'm sorry, "spreading truth?" I think you mean blatantly lying, vandalizing wiki pages, and trolling. Your IP is Cloudflare's and you haven't used this IP to vandalize, but let's be honest, we all know that you're the anti-semitic lunatic who's been trolling and vandalizing pages recently. Just stop. Herobrine (talk) 07:27, 5 May 2019 (UTC)
See https://www.youtube.com/watch?v=zUyH3XhpLTo162.158.78.82 18:26, 11 April 2019 (UTC)
HAVE YOU TRIED WALKING INTO THE SEA (can't find the relevant xkcd sorry) on a more serious note, I'd be for banning IP editors myself, it wouldn't matter much and just stop me from editing on mobile. If the comments section could somehow be left IP editable but not the articles, that would be an interesting Midway point, but any degree necessary is fine. -- (talk) (please sign your comments with ~~~~)
Sign your posts you fucking cunt 15:37, 12 April 2019 (UTC)
1912: Thermostat -- Hkmaly (talk) 22:24, 12 April 2019 (UTC)

Anyone else find it ironic for an IP editor to refer to logged-in editors as IP editors? That's the pot calling the brass teapot black! Ianrbibtitlht (talk) 06:09, 12 April 2019 (UTC)

As I understand the link "The black hole’s boundary — the event horizon from which the EHT takes its name — is around 2.5 times smaller than the shadow it casts and measures just under 40 billion km across." This is actually showing the wrong scale by a factor of 2.5 - voyager 1 is about at the event horizon, only 40% of the way out of the shadow. Going to edit this but wanted to add discussion here as well. Numberland (talk) 20:28, 14 April 2019 (UTC)

Note that the dimension of the shadow should be measured from the centroid of the ring, not from its inner boundary, since this is a greatly unresolved convolution of a sharp, narrow ring with a roughly gaussian beam from the EHT. Considering that, Munroe's dimensions appear to be essentially correct. -astronomer who happened by this page today but doesn't have an account

Images from this page[1] show an exact scale in microarcseconds. 1 microarcsecond at 4.978×10^23 meters away is 2.414×10^12 meters across. And there's 50 of those in that white line. First off, whoa. Second off, the diameter of the orbit of Pluto should then be about 9.788% of the length of the line. I'll leave it to someone else to figure out how that corresponds to the image in the comic exactly. 07:09, 5 May 2019 (UTC)

Sure thing. The comic with scale: https://postimg.cc/nMMjBQFC The original image with scale: https://postimg.cc/Zv9WSX7r Oddly enough, it seems the solar system in the comic is actually a bit small. The "meterstick" is 308 px across, so you would expect the solar system to be about 30 px across, but it's smaller. I'm editing the page to reflect this. 07:23, 11 February 2020 (UTC)