Scroll down to read this post.

 

Please consider supporting my work here at Behind the Black. I keep the website clean from pop-ups and annoying demands. Instead, I depend entirely on my readers to support me. Though this means I am sacrificing some income, it also means that I remain entirely independent from outside pressure. By depending solely on donations and subscriptions from my readers, no one can threaten me with censorship. You don't like what I write, you can simply go elsewhere.

 

You can support me either by giving a one-time contribution or a regular subscription. There are five ways of doing so:

 

1. Zelle: This is the only internet method that charges no fees. All you have to do is use the Zelle link at your internet bank and give my name and email address (zimmerman at nasw dot org). What you donate is what I get.

 

2. Patreon: Go to my website there and pick one of five monthly subscription amounts, or by making a one-time donation.
 

3. A Paypal Donation:

4. A Paypal subscription:


5. Donate by check, payable to Robert Zimmerman and mailed to
 
Behind The Black
c/o Robert Zimmerman
P.O.Box 1262
Cortaro, AZ 85652

 

You can also support me by buying one of my books, as noted in the boxes interspersed throughout the webpage or shown in the menu above. And if you buy the books through the ebookit links, I get a larger cut and I get it sooner.


First radio image of event horizon of Milky Way’s central black hole

Sagittarius A*
Click for full image.

Using an array of eight radio telescopes worldwide, dubbed the Event Horizon Telescope because its purpose is to study black holes, scientists have obtained the first radio image of the event horizon of Sagittarius A* (pronounced “A-star”), the supermassive black hole at the center of the Milky Way.

The image to the right, reduced to post here, is that photo.

The image is a long-anticipated look at the massive object that sits at the very centre of our galaxy. Scientists had previously seen stars orbiting around something invisible, compact, and very massive at the centre of the Milky Way. This strongly suggested that this object — known as Sagittarius A* (Sgr A*, pronounced “sadge-ay-star”) — is a black hole, and today’s image provides the first direct visual evidence of it.

Although we cannot see the black hole itself, because it is completely dark, glowing gas around it reveals a telltale signature: a dark central region (called a “shadow”) surrounded by a bright ring-like structure. The new view captures light bent by the powerful gravity of the black hole, which is four million times more massive than our Sun.

This is the second supermassive black hole that the Event Horizon array has imaged. In 2019 it captured the central black hole of the galaxy M87, 55 million light years away. Like that first image, much of what we see here is created by computer, since the data from the eight radio telescopes needs to be massaged to create something as smooth and as complete as this.

Genesis cover

On Christmas Eve 1968 three Americans became the first humans to visit another world. What they did to celebrate was unexpected and profound, and will be remembered throughout all human history. Genesis: the Story of Apollo 8, Robert Zimmerman's classic history of humanity's first journey to another world, tells that story, and it is now available as both an ebook and an audiobook, both with a foreword by Valerie Anders and a new introduction by Robert Zimmerman.

 
The ebook is available everywhere for $5.99 (before discount) at amazon, or direct from my ebook publisher, ebookit. If you buy it from ebookit you don't support the big tech companies and the author gets a bigger cut much sooner.


The audiobook is also available at all these vendors, and is also free with a 30-day trial membership to Audible.
 

"Not simply about one mission, [Genesis] is also the history of America's quest for the moon... Zimmerman has done a masterful job of tying disparate events together into a solid account of one of America's greatest human triumphs."--San Antonio Express-News

9 comments

  • Phill O

    Not to mention, the human eye does not see radiowaves.

    Great image!

  • Col Beausabre

    Not to mention, the human eye does not see radiowaves.

    Except for those of us who have evolved further than the masses

  • GaryMike

    To clarify for those who think the dark center of the image is the black hole itself, the dark center is the shadow of the black hole acting like the occulting disk in a solar telescope.

  • wayne

    The Black Hole Image (M87) Explained
    Veritasium –>from 2019
    https://youtu.be/zUyH3XhpLTo
    9:18

    explains the geometry very well

  • GaryMike

    Thank you.

    I learned more stuff.

    Like, no matter how much you know, it ain’t enough.

  • wayne

    GaryMike-
    -check out Scott Manley as well for nicely done black-hole info.

    “Mass of Sagittarius A* calculated from SO-2 (S2) Star’s Orbital Parameters”
    Dr. Andrew R. Ochadlick Jr (2016)
    https://youtu.be/mT1_vol_F_0
    7:08

  • Star Bird

    When will they find a Worm Hole to the further away and the Galactic Barrier?

  • Steven Carleton

    They’ve covered this in episodes of “How the Universe Works” on Discovery Channel.
    They featured an MIT prof (Seth something) who they seemed to present as the brain behind it all.
    The global radio telescopes gather so much data that they have to ship the hard-drives to MIT, since the public internet would take too long to transfer terabytes of data every hour.

  • Steven Carleton

    https://newsroom.ucla.edu/releases/andrea-ghez-wins-2020-nobel-prize-in-physics

    Well deserved! She and her team spent countless nights, year after year, recording how Sag-A at our galactic core flung stars around at incredible velocities. They had to look deep into the core of the Milky Way from the Keck telescope, looking for minute data blips on computer screens. Monica also could back up her observations with theories to describe the data. Say, how does one get some time on Keck?

Readers: the rules for commenting!

 

No registration is required. I welcome all opinions, even those that strongly criticize my commentary.

 

However, name-calling and obscenities will not be tolerated. First time offenders who are new to the site will be warned. Second time offenders or first time offenders who have been here awhile will be suspended for a week. After that, I will ban you. Period.

 

Note also that first time commenters as well as any comment with more than one link will be placed in moderation for my approval. Be patient, I will get to it.

Leave a Reply

Your email address will not be published. Required fields are marked *