April… Showers?

We interrupt this regularly scheduled blog post for an Important Weather Update! Afterwards, please stay tuned for News From Space!

Holy Canole, Batman, talk about your Before (During) and After pictures!

4/10/2019 12:43

12:43 PM All that snow had finally melted!

It was one of those days where it was brightest in the morning and got darker as the day wore on and the clouds rolled in…

4/10/2019 14:11

2:11 PM Heavy wet flakes begin to fall.

Once it started falling, it didn’t take long for it to lay down a white coating. Within a few hours:

4/10/2019 17:24

5:24 PM And Winter is Back!

It was winter again. Damn it. Kinda hoped it was all behind us now.

Earlier just this week I opened the windows for the first time and let the lovely spring air stream through the house. Now look at it:

4/11/2019 09:12

This Morning: Time to go shovel.

Which means I get to go out and “play” in the snow again:

4/11/2019 11:52

Later This Morning: Time to eat breakfast!

I guess it’s one way to get your exercise.

If April showers bring May flowers, what will this bring? Killer snowmen?

Yikes!

§

In completely unrelated news, we got our first “photo” of a black hole:

WOW

Super-massive black hole in the center of M87 — a portrait!

The effort involved producing this image is impressive.

Firstly, the image is from radio-frequency photons emitted from the region of that black hole. Specifically, radio light from the super-heated accretion ring.

(So, of course, the colors are false. Radio light has no “color” to speak of.)

Secondly, the image was created with VLBI using radio telescopes from all over the Earth. That creates a virtual radio-telescope of unprecedented resolution.

The image above represents a visual size of about 50 micro-arc-seconds! That’s 50-millionths of one-sixtieth of one-sixtieth of a degree. (There are 60 arc-minutes in a degree, and 60 arc-seconds in an arc-minute.)

Thirdly, each telescope gathered many petabytes of information per observation — carefully time-stamped data representing the waveforms measured by the instrument.

The data was so vast it couldn’t be sent over the internet. Instead, it was loaded on (many, many) hard drives and shipped to a central destination…

Fourthly, where powerful computers spent two years crunching data to reconstruct the image seen above. (The observations were all made in 2017.)

And now, for the first time, we have an image — a portrait is, I think, the best word for it — of an actual black hole.

Final proof they really do exist.

§

The portrait above is of the super black hole in the nearby galaxy M87.

That, alone, is impressive. It’s 55 million light years away.

And that particular black hole, with 6.5 billion solar masses, is the largest we know.

It’s huge and very active, which is why it was chosen. It turns out that, even at 55 million light years away, its visual size from Earth is roughly the same as that of the black hole in the center of our galaxy.

(Which the scientists also imaged although I can’t seem to find that image online right now.)

Kudos to all involved!

§

Now can we please get back to spring? A few days ago it was almost 70 degrees out. It hasn’t gotten above 35 today!

Stay warm, my friends!

About Wyrd Smythe

The canonical fool on the hill watching the sunset and the rotation of the planet and thinking what he imagines are large thoughts. View all posts by Wyrd Smythe

16 responses to “April… Showers?

  • David Davis

    Shipping hard drives sounds like something out of the eighties. Thanks for the info–I haven’t been following the story too closely.

  • SelfAwarePatterns

    On shipping hard drives, it’s funny how sometimes, the more things change, the more they remain the same. Both AWS and Azure have services to allow you to ship large datasets on physical hard drives, mostly to save on bandwidth charges and/or avoid clogging VPN pipes. Although plane loads, yikes!

    I read the technique to image the black hole won’t work for exoplanets, which is a pity. Although I’m sure using geographically distributed telescope arrays is something we’re going to see more of. If they could ever build a space based array like that, with an effective virtual dish side maybe millions of kilometers wide, we might see all kinds of things.

    From what I’ve heard, the reason you haven’t seen Sagittarius A* yet is it’s a much more difficult case due to the angle and all the clutter, and it’s still being worked on.

    • Wyrd Smythe

      “I read the technique to image the black hole won’t work for exoplanets,…”

      That makes sense. The technique depended on RF photons emitted by the hot accretion ring. Exoplanets are a lot colder. I quite agree that interferometry astronomy will grow (looking forward to it)! Imagine if we could plant telescopes all along the asteroid belt. Very wide aperture!

      “From what I’ve heard, the reason you haven’t seen Sagittarius A* yet is it’s a much more difficult case due to the angle and all the clutter, and it’s still being worked on.”

      I thought I saw an image in that Veritasium video. I’ll have to watch the video again.

      As I understand it, the image wouldn’t change that much due to angle. The warping of space means you’ll always see that “ring of fire” effect. The clutter between here and there is a significant problem, I imagine.

      Amazing that they’re nearly the same size visually to us. M87* is big! Bigger than the solar system.

      • SelfAwarePatterns

        “The warping of space means you’ll always see that “ring of fire” effect.”

        That’s interesting. So even if the photo is taken from an angle close to the plane of the accretion disk, as I think it would be for Sagittarius A*, it will still look like a ring of fire to us? I would’ve expected a hole with a line of fire passing through it. And would we see it for a stellar black hole not currently feeding?

      • Wyrd Smythe

        I just re-watched the two Veritasium videos (linked below). One reason they’re still working on the Sag A* image is that the black hole isn’t active, which does make it harder. As I understand it, we should still be able to image the accretion ring.

        The second video below explains this very well, but basically, gravity bends the light rays such that we see behind the black hole. No matter where the accretion disk is relative to an observer, light rays always bend around the hole and come towards the observer. So you always see the ring of fire in some form.

        That famous image from the movie, Interseller, was generated according to GR and does illustrate what things would look like edge on. You would see the accretion disk bisecting the image, but also the ring of fire. (My guess is that not enough photons come from a disk edge on such that we’d capture enough to see it on Sag A*.)

        I see my confusion thinking the Sag A* image was out already. That first video shows a simulation of the image for comparison to the M87* image. I missed that it was a simulation.

    • Wyrd Smythe

      FYI, some interesting links below. I highly recommend the last one, the post-release talk Dr. Bouman gave at Cal Tech. Lots of details about how they processed the image.

  • Wyrd Smythe

    Ah, and here’s the Katie Bouman herself!

    (I watched this a year ago; completely forgot about it.)

    • Wyrd Smythe

      How disappointing it was to read an article this morning about how Dr. Bouman is being harassed by online trolls who can’t stand that a woman played a key role in this impressive work of science.

      Part of the problem started with the media making a big deal out of her. While she is a key member, the team of 200 is what accomplished the goals. Dr. Bouman tried to deflect the media attention.

      But it woke up the trolls. Let’s just hope they have their usual short attention spans and find some other outrage to spit vitriol at.

  • Wyrd Smythe

    Naturally, xkcd has a great take on this:

    https://xkcd.com/2135/

    With a great picture showing the size of our solar system compared to the image of M87*.

  • Wyrd Smythe

    This article from The Atlantic is about the shipping of hard drives:

    https://www.theatlantic.com/science/archive/2019/04/black-hole-hard-disks-picture/587119/

    It includes a picture of a bundle of hard drives and sources the line about how, “Nothing beats the bandwidth of a 747 filled with hard disks.” It’s by Mike Titus, ‘the researcher who operated the supercomputer that helped synthesize all the data into a single, composite image.’

  • Wyrd Smythe

    And, finally, here’s a talk by Dr. Bouman given after the release of the black hole image. (I haven’t watched it, yet.)

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