Creationism and Our Galaxy’s Central Black Hole

YOU MAY have heard the recent news about observations regarding the immense black hole believed to lie at the center of our galaxy. Here’s one article at Scientific American: Closing In on the Milky Way’s Central Black Hole. It’s interesting stuff. For example:

Ghez’s team [that’s Andrea Ghez, a professor of astronomy at the University of California, Los Angeles], focused on S2, a relatively bright star with a short orbit around the black hole, whereas Gillessen’s group [that’s astrophysicist Stefan Gillessen of the Max Planck Institute for Extraterrestrial Physics in Garching, Germany] determined the orbits of 28 stars, including S2. “It really is amazing to see that we can describe the motions of that many stars” by assuming one massive central anchor, Gillessen says. “The stars fly around wildly, in all directions, at different radii. But all that governs that is simply Newton’s law.”

The motion of S2, Gillessen says, gives an outer boundary to the central object, which, combined with its inferred mass, helps prove that it is a black hole. “Having four million solar masses sitting there, not shining…and being confined by [the orbit of] the star S2 is really a convincing case,” he says.

And this is very intriguing:

In principle, these stars could test general relativity, because they get into a very strong gravitational field at the central black hole,” Ghez says. “And if the measurements are precise enough, you should be able to see the impacts on the orbit.”

As fascinating as this is, your Curmudgeon doesn’t usually write about such matters, preferring to stick with familiar territory. But the highly esteemed creationist website of the Institute for Creation Research (ICR) doesn’t recognize any boundaries on their expertise.

We marvel at the vast sweep of the knowledge mastered by the folks at ICR. Here, for your edification, is the creationist view of this new astronomical observation: Fast-orbiting Stars Puzzle Astronomers. The bold font was supplied by us.

First, they mention the news:

German astronomers have been meticulously tracking the orbits of 28 stars nearest to the center of the Milky Way spiral galaxy. Over the 16 years of their study, one of the stars travelled so fast that it completed a full revolution. Though the galactic core is dark, its mass has been estimated based on the behavior of the stars that orbit it so closely. These observations seem to confirm that a black hole exists at the core of the Milky Way, but they also raise significant questions about the stars’ origins.

Questions about the stars’ origins? The Scientific American article seems to have missed that. Let’s read on:

They quote a single sentence from this article at the website of the European Southern Observatory (ESO):

Excitingly, future observations are already being planned to test several theoretical models that try to solve this riddle.

What riddle? The one ICR mentioned about the origins of the stars? Unlike the typical ICR reader, we looked at the referenced ESO article. Here’s the relevant quote:

One particular star, known as S2, orbits the Milky Way’s centre so fast that it completed one full revolution within the 16-year period of the study. Observing one complete orbit of S2 has been a crucial contribution to the high accuracy reached and to understanding this region. Yet the mystery still remains as to how these young stars came to be in the orbits they are observed to be in today. They are much too young to have migrated far, but it seems even more improbable that they formed in their current orbits where the tidal forces of the black hole act. Excitingly, future observations are already being planned to test several theoretical models that try to solve this riddle.

Aha! In true creationist fashion, they quote-mined ESO to convert a “riddle” about orbits into a question about the origins of stars. Having invented this cosmic riddle, what are they going to do with it?

Let’s skip to the end of the creationist article. They conclude, not with the hope of testing general relativity, but with a surprising prediction — although we should have expected it. Here it is, with bold added by us:

The precise construction parameters of cosmic structures like these stars and the rules that govern them will only be intelligible as products of a supernatural Creator.

We’ve been avoiding subjects like this because of our lack of expertise. But ICR boldly goes where we fear to tread, and fearlessly predicts that their theory will prevail. We shall see.

Copyright © 2008. The Sensuous Curmudgeon. All rights reserved.

. AddThis Social Bookmark Button . Permalink for this article

16 responses to “Creationism and Our Galaxy’s Central Black Hole

  1. This story permits me to encourage those prone to curiosity to learn more about how they deduce the mass of the black hole at the center of the galaxy by observing the orbits of the stars in proximity to it: the Virial Theorem:

    http://www.astro.cornell.edu/academics/courses/astro201/vt.htm

  2. retiredsciguy

    If S2 completes an orbit in 16 years, it may be moving at a sizable percentage of the speed of light, which would explain why the star appears younger than it should. Time slows down as the speed of light is approached.

    Another possibility — the strong gravitational field of the black hole might have the same time dilation effect.

  3. retiredsciguy, I can’t be sure of the velocity of those stars from the articles I’ve seen. S2 orbited the central black hole in only 16 years, and they say it’s at least a light-month away from the event horizon, but we really need to know the circumference of its orbit to know the velocity. If it’s exactly a light-month away, then its orbit is 2pi times that (well, it’s an ellipse, but let’s ignore that), thus it’s moving about 6 light-months every 16 years. Could be faster if the orbit is further out, but that’s the general idea. (For comparison, Earth is only 8 light-minutes from the sun, so S2 is quite far from the black hole.)

    That means S2 travels half a light year in 16 years, so it would take 32 years to travel a full light year. It’s 1/32 times the speed of light. That’s fast compared to what we can do (about 1% of 1% of lightspeed), but not nearly fast enough to show any significant time dilation.

    [Edited because I goofed up the formula for the circumference of a circle. Duh!]

  4. I had to do the math. Traveling at 3% of lightspeed, time does slow down, of course, but not very much. It’s .99954989% of “normal” time. Probably not noticeable, unless you sent a ship out at that speed and then brought it back to compare its clock with a “twin” clock that stayed at home.

  5. retiredsciguy

    Yeah, I checked the referenced article in SA to get an idea of the orbit size, but it wasn’t mentioned, except to say what it’s closest approach is. I’m thinking it’s probably a highly elliptical orbit, and that would mean it’s REALLY whizzing at “periblackholeion”, which would make the time dilation much more significant.

    And too, doesn’t the strong gravitational field have an effect on time? I thought I read that somewhere (probably a sci-fi short story from my youth).

    At any rate, these may explain the apparent youth of S2, when by all rights it should be a much older star.

  6. That’s unlikely to be the answer. Even at 50% of lightspeed — and this star is doing only 3% or maybe 4% of lightspeed, time dilation would make it 86.6% of its “normal” age. Not all that young, really. Relativistic effects don’t kick in strongly until well above 95% of lightspeed. The gravity field can also have such an effect, but I suspect that if the star is still surviving in orbit, and its orbit is virtually Newtonian, it’s far enough away from the black hole that it’s not a significant factor.

    Longshadow knows more about this than I do, and Rades (who recently appeared making a comment in a different thread) knows more than all of us. So if I’ve goofed up, they’ll say so.

  7. What a lying little [poop-head] the author of that [poop] is. Where is the require ellipsis?

    Yet the mystery still remains as to how these young stars came to be [||**||##] in the orbits they are observed to be in today.

    In the above quote I searched out, found and marked the bias blocker that stopped the author from going past what fit into his preconceptions.

    This, invisible to the educated, vicious little bugger infests many scientific articles read by cretards and stops them from understanding (warning, ellipsis misuse ahead) ,… oh, basically anything written.

    The precise construction parameters of cosmic structures like these stars and the rules that govern them will only be intelligible as products of a supernatural Creator.

    That must be true, cause it sounds all sciency and intelligent and stuff, with all them impress me up the bazooka big words. Don’t it?

  8. Calm down, Tundra Boy. After all, it’s creationism. You have to expect that kind of thing.

  9. Expect? Yes.
    Like? No way.

    Well, I guess it isn’t really their fault, God is making them do it after all.

  10. retiredsciguy

    Quoting from the SA article, “In 2002, Gillessen says, S2 passed within 16 light-hours of the black hole’s event horizon, or point of no return…”
    I guess the question is, how far out from a 4-million solar mass black hole is the event horizon? I wish the article had stated how close S2 came to the black hole itself, rather than the event horizon.
    at any rate, 16 light-hours is about 4 times Neptune’s distance from the Sun, for what it’s worth. So even if S2’s orbit is highly elliptical, you are probably right — it’s not going fast enough for relativistic effects to account for it’s apparent youth.
    Maybe the fact that the black hole is pulling off a lot of matter from S2 keeps it looking young. But hey, I’m just a retired 7th-grade science teacher and amateur astronomer, not an astrophysicist. What wasn’t explained in the article is what characteristics of S2 make us think it’s young.

  11. The event horizon’s size is defined by the Schwartzschild radius:

    rs= 2Gm/c2

    where G is the gravitational constant, m the mass of the black hole, and c the speed of light.

    Since, according to Wikipedia, 2G/c2 is approximately 1.48×10-27 m/kg, or 2.95 km/solar masses, it follows that a black hole with a mass equal to 4 x 106 solar masses should have an event horizon located at a radius of just under 12 million km.

  12. oops, left out a few superscripts:

    Since, according to Wikipedia, 2G/c2 is approximately 1.48×10-27 m/kg, or 2.95 km/solar masses, it follows that a black hole with a mass equal to 4 x 106 solar masses should have an event horizon located at a radius of just under 12 million km.

    That’s better.

  13. Damn! This bloody blog won’t let me do superscripts!

  14. Longie said: “This bloody blog won’t let me do superscripts!”

    The comments feature is rather primitive. You can do bold and italics, and blockquote, but that’s probably all.

  15. Waaaaaaa! It’s a conspiracy to suppress scientific formulae!

    Grumble, grumble, harrumphhhhhh ….

  16. I will not be thwarted by this evil blog software:

    The event horizon’s size is defined by the Schwartzschild radius:

    r-sub-s= 2Gm/c^2

    where G is the gravitational constant, m the mass of the black hole, and c the speed of light.

    Since, according to Wikipedia, 2G/c^2 is approximately 1.48×10^-27 m/kg, or 2.95 km/solar masses, it follows that a black hole with a mass equal to 4 x 10^6 solar masses should have an event horizon located at a radius of just under 12 million km.