A lopsided spiral galaxy
Click for full image.
For a change, today’s cool image is not from Mars, but instead goes deep into space. The photo to the right, reduced to post here, was taken by the Hubble Space Telescope of the relatively nearby spiral galaxy NGC 2276, located about 120 million light years away. As the caption explains:
The magnificent spiral galaxy NGC 2276 looks a bit lopsided in this Hubble Space Telescope snapshot. A bright hub of older yellowish stars normally lies directly in the center of most spiral galaxies. But the bulge in NGC 2276 looks offset to the upper left.
In reality, a neighboring galaxy to the right of NGC 2276 (NGC 2300, not seen here) is gravitationally tugging on its disk of blue stars, pulling the stars on one side of the galaxy outward to distort the galaxy’s normal fried-egg appearance. This sort of “tug-of-war” between galaxies that pass close enough to feel each other’s gravitational pull is not uncommon in the universe. But, like snowflakes, no two close encounters look exactly alike.
The scientists also note that the bright edge along the galaxy’s north and west perimeter mark regions of intense star-formation. In those same regions astronomers six years ago identified the first medium-sized black hole ever found.
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In 2020 when the world panicked over COVID I wrote that the panic was unnecessary, that the virus was apparently simply a variation of the flu, that masks were not simply pointless but if worn incorrectly were a health threat, that the lockdowns were a disaster and did nothing to stop the spread of COVID. Only in the past year have some of our so-called experts in the health field have begun to recognize these facts.
Your help allows me to do this kind of intelligent analysis. I take no advertising or sponsors, so my reporting isn't influenced by donations by established space or drug companies. Instead, I rely entirely on donations and subscriptions from my readers, which gives me the freedom to write what I think, unencumbered by outside influences.
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Click for full image.
For a change, today’s cool image is not from Mars, but instead goes deep into space. The photo to the right, reduced to post here, was taken by the Hubble Space Telescope of the relatively nearby spiral galaxy NGC 2276, located about 120 million light years away. As the caption explains:
The magnificent spiral galaxy NGC 2276 looks a bit lopsided in this Hubble Space Telescope snapshot. A bright hub of older yellowish stars normally lies directly in the center of most spiral galaxies. But the bulge in NGC 2276 looks offset to the upper left.
In reality, a neighboring galaxy to the right of NGC 2276 (NGC 2300, not seen here) is gravitationally tugging on its disk of blue stars, pulling the stars on one side of the galaxy outward to distort the galaxy’s normal fried-egg appearance. This sort of “tug-of-war” between galaxies that pass close enough to feel each other’s gravitational pull is not uncommon in the universe. But, like snowflakes, no two close encounters look exactly alike.
The scientists also note that the bright edge along the galaxy’s north and west perimeter mark regions of intense star-formation. In those same regions astronomers six years ago identified the first medium-sized black hole ever found.
Readers!
Please consider supporting my work here at Behind the Black. Your support allows me the freedom and ability to analyze objectively the ongoing renaissance in space, as well as the cultural changes -- for good or ill -- that are happening across America. Fourteen years ago I wrote that SLS and Orion were a bad ideas, a waste of money, would be years behind schedule, and better replaced by commercial private enterprise. Only now does it appear that Washington might finally recognize this reality.
In 2020 when the world panicked over COVID I wrote that the panic was unnecessary, that the virus was apparently simply a variation of the flu, that masks were not simply pointless but if worn incorrectly were a health threat, that the lockdowns were a disaster and did nothing to stop the spread of COVID. Only in the past year have some of our so-called experts in the health field have begun to recognize these facts.
Your help allows me to do this kind of intelligent analysis. I take no advertising or sponsors, so my reporting isn't influenced by donations by established space or drug companies. Instead, I rely entirely on donations and subscriptions from my readers, which gives me the freedom to write what I think, unencumbered by outside influences.
You can support me either by giving a one-time contribution or a regular subscription. There are four 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 or subscription:
4. 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.
Great Pic!!! $ir !
….
…. and the Heavens proclaim …
Wondering how Kepler’s Third Law would affect stars and their systems. I would think that as the galaxy’s major axis expanded, stars would whip around the core fast enough that the night sky would have noticeable changes in a lifetime.
Kepler’s Third Law;
“Kepler discovered that the size of a planet’s orbit (the semi-major axis of the ellipse) is simply related to sidereal period of the orbit”
For instance, the days between winter solstice and summer solstice are equal. Spring equinox to fall equinox is seven days longer than the opposite do to earths elliptical orbit.
Gravity is weak, you must be near a large mass to feel its affect. Which gets weaker quickly the further you get from that mass.
bkivey said;
“Wondering how Kepler’s Third Law would affect stars and their systems. I would think that as the galaxy’s major axis expanded, stars would whip around the core fast enough that the night sky would have noticeable changes in a lifetime.”
The far side of the galaxy appears to be pulled towards the center mass accelerating. So that’s probably true…
For the most part, the stars at the inner core move slower than those in the middle or towards the edge of the galaxy. It’s not Newtonian physics so they came up with dark matter to explain it. (Which only confused things without resolving the issue)
Because most galaxies turn like a record player, all about the same rate, the speed increasing the further you get from the center, there must be something else at work. This picture is a good example of the influence of a gravity of a Galaxy nearby. It pulls everything out of whack, a obvious response to its presence indicating that it’s the combined “mass of the galaxy” which holds everything in check with each other.
Other words, A slow moving star will drop towards the strongest gravitational attraction, the center, where all the slow stars go.
A fast moving star will find itself on the edge of the galaxy trying to escape but being held in place by the combining of the weak gravity of all the billions of stars in the galaxy.
A great example of this is the “irregular galaxy” which is the most common and looks like a fuzzy snowball. Every star has its own elliptical path through the center of it’s galaxy accelerating until it comes out the other side and is pulled back in for another pass.
Untill another Galaxy’s gravity comes near and gives a little tug. Something Andromeda will do to our galaxy someday.
Kepler’s Third Law applies to elliptical orbits in a two body system. One could think of the second galaxy, as it relates to a star in the first galaxy, as a third body, which makes Kepler’s Third Law inappropriate. Even within the first galaxy, Kepler’s Third Law does not apply, because it is also not a two body system.
Gravity drops off with increasing distance from a mass by the inverse square law. This is why orbits are elliptical in the first place. However, once inside a sphere of uniform density, gravity drops off linearly with decreasing distance to the center. Thus, maximum gravity is felt on the surface of the sphere. This would be a similar phenomenon for a disk of uniform density, which is almost a reasonable model for a spiral galaxy (the center of which is typically more dense than the rest of the disk, which isn’t really uniformly dense, either). I’m not sure what shape a non-circular orbit would take, inside a galaxy, but the mass distribution means that usual (two body) laws of orbital mechanics don’t apply.
The universe is a weird place.