Bad Astronomy (@BadAstonomer): When Galaxies Strip For Each Other

Polar ring galaxies are, as you might expect from seeing them, rather odd.

The outer ring in Hoag’s Object (bottom picture) has lots of young, hot stars, and the gas and dust needed to keep forming them, while the center, looking very yellow, is full of older stars and no star formation.

NCG 660 has a similar ring, but it is out of kilter (Hoag’s is perpendicular to the central core) and warped.

So, Phil tells us he read up on it and found that galaxies in near-passes (instead of collisions) can end up pulling the gas and dust out of each other, and into these rings. And, since they are moving slowly, the gravitational tidal forces start pulling the gas and dust into different places in the galaxy, even the center. So, while Hoag’s Object has no star formation in the center, NGC 660 has a bit of star formation both in the ring and in the center.

Phil learns something new and so, then, do we all. (Because, hey, let’s face it, he’s a professional astronomer and can understand these things quite a bit more easily than I can, and then he explains pretty well, too.)

(via Revealing the Universe: the Hubble Extreme Deep Field | Bad Astronomy | Discover Magazine)
Almost everything you see in that picture is a galaxy (you can tell foreground stars by the diffraction spikes). This is old news, I’m sure, to some of you, but the Hubble team started with the original Hubble Ultra Deep Field (which I blogged about last night) and started adding data, and adding data, and just adding more and more data. The overall combined data is about 23 days worth of continuous observation!
There are about 5500 galaxies in that image. The light from some of them has been travelling for 13 billion years, and are, in this image, only about 500 million years old.
Baby galaxies, folks. Baby galaxies.

(via Revealing the Universe: the Hubble Extreme Deep Field | Bad Astronomy | Discover Magazine)

Almost everything you see in that picture is a galaxy (you can tell foreground stars by the diffraction spikes). This is old news, I’m sure, to some of you, but the Hubble team started with the original Hubble Ultra Deep Field (which I blogged about last night) and started adding data, and adding data, and just adding more and more data. The overall combined data is about 23 days worth of continuous observation!

There are about 5500 galaxies in that image. The light from some of them has been travelling for 13 billion years, and are, in this image, only about 500 million years old.

Baby galaxies, folks. Baby galaxies.

The Hubble Ultra Deep Field in 3D (by tdarnell)

Ho-ly. For those that don’t know, the Ultra Deep Field was taken by pointing Hubble at a blank patch of sky near Orion. Seriously, all other observations of this spot were blank. They left it open for 11 days straight. The found some of the oldest galaxies we’ve ever detected.

And now, they’ve taken the redshift data from the Ultra Deep Field…and used it to render a 3-D animation of going “through” the image.

Oh, and I come across this as a result of Phil Plait’s post about the latest Deep Field image, the Hubble Extreme Deep Field. More on that later.

(via SDSS Galaxy Map)
The map of the galaxies in the universe from the Sloan Digital Sky Survey (amalgamated data from all three main runs plus SEGUE) from the SDSS website.
This is a flat representation of the data in the video from earlier this week. These are the galaxies out to about 2 billion light-years or 0.15 redshift.
Distances this far out are often given in redshift because of Hubble’s Law. Hubble discovered, as you may know, that all galaxies are moving away from each other on a macro level, and the farther away a galaxy is, the faster it is moving away from us. Faster objects undergo more redshift in their light when it gets to us. That means that the speed at which a galaxy is moving away is an indicator of how far away it is. We can translate that into a number of light-years, but the reality is that we are using Hubble’s Law to determine that distance anyway, so giving distance in redshift is apropos.
(Note that SDSS captures Type Ia supernovae as well, a great standard candle for checking the redshift against other aspects of the distance ladder used by astronomers. The Sloan Supernova Survey )
Via SDSS.org

(via SDSS Galaxy Map)

The map of the galaxies in the universe from the Sloan Digital Sky Survey (amalgamated data from all three main runs plus SEGUE) from the SDSS website.

This is a flat representation of the data in the video from earlier this week. These are the galaxies out to about 2 billion light-years or 0.15 redshift.

Distances this far out are often given in redshift because of Hubble’s Law. Hubble discovered, as you may know, that all galaxies are moving away from each other on a macro level, and the farther away a galaxy is, the faster it is moving away from us. Faster objects undergo more redshift in their light when it gets to us. That means that the speed at which a galaxy is moving away is an indicator of how far away it is. We can translate that into a number of light-years, but the reality is that we are using Hubble’s Law to determine that distance anyway, so giving distance in redshift is apropos.

(Note that SDSS captures Type Ia supernovae as well, a great standard candle for checking the redshift against other aspects of the distance ladder used by astronomers. The Sloan Supernova Survey )

Via SDSS.org

(via Giant galaxy cluster sets record pace for creating stars | UChicago News)

Astronomers have found an extraordinary galaxy cluster — one of the largest objects in the universe — that is breaking several important cosmic records. The discovery of this cluster, known as the Phoenix Cluster, made with the National Science Foundation’s South Pole Telescope, may force astronomers to rethink how these colossal structures, and the galaxies that inhabit them, evolve.

Follow-up observations made in ultraviolet, optical and infrared wavelengths show that stars are forming in this object at the highest rate ever seen in the middle of a galaxy cluster. The object also is the most powerful producer of X-rays of any known cluster, and among the most massive of clusters. The data also suggest that the rate of hot gas cooling in the central regions of the cluster is the largest ever observed.

…

Officially known as SPT-CLJ2344-4243, this galaxy cluster has been dubbed the “Phoenix Cluster” because it is located in the constellation of the Phoenix, and because of its remarkable properties.
Stars forming at incredible rates
Like other galaxy clusters, Phoenix holds a vast reservoir of hot gas that contains more normal matter than all of the galaxies in the cluster combined. The reservoir of hot gas can be detected with X-ray telescopes like NASA’s Chandra X-ray Observatory, and the shadow it makes in the light from the big bang can be detected with the South Pole Telescope. The prevailing wisdom had once been that this hot gas should cool over time and sink to the center of the cluster, forming huge numbers of stars.
However, most galaxy clusters have formed very few stars over the last few billion years.
Astronomers think that the supermassive black hole in the central galaxy of clusters pumps energy into the system, preventing cooling of gas from causing a burst of star formation. The famous Perseus Cluster is an example of a black hole bellowing out energy and preventing the gas from cooling to form stars at a high rate.
With its black hole not producing powerful enough jets, the center of the Phoenix Cluster is buzzing with stars that are forming 20 times faster than in the Perseus Cluster. This rate is the highest seen in the center of a galaxy cluster and is comparable to the highest seen anywhere in the universe.

…

Galaxy clusters contain enough hot gas to create detectable “shadows” in the light left over from the big bang, which also is known as the cosmic microwave background radiation. This light has literally travelled for 14 billion years across the entire observable universe to get to Earth. If it passes through a massive cluster on its way, then a tiny fraction of the light gets scattered to higher energies — the Sunyaev-Zel’dovich effect.
The South Pole Telescope collaboration has now completed an SZ survey of a large region of the sky finding hundreds of distant, massive galaxy clusters. Further follow-up observations of the clusters at X-ray and other wavelengths may reveal the existence of additional Phoenix-like galaxy clusters.


Artist’s impression of the galaxy at the center of the Phoenix Cluster. Courtesy of NASA/CXC/M. Weiss

(via Giant galaxy cluster sets record pace for creating stars | UChicago News)

Astronomers have found an extraordinary galaxy cluster — one of the largest objects in the universe — that is breaking several important cosmic records. The discovery of this cluster, known as the Phoenix Cluster, made with the National Science Foundation’s South Pole Telescope, may force astronomers to rethink how these colossal structures, and the galaxies that inhabit them, evolve.

Follow-up observations made in ultraviolet, optical and infrared wavelengths show that stars are forming in this object at the highest rate ever seen in the middle of a galaxy cluster. The object also is the most powerful producer of X-rays of any known cluster, and among the most massive of clusters. The data also suggest that the rate of hot gas cooling in the central regions of the cluster is the largest ever observed.

Officially known as SPT-CLJ2344-4243, this galaxy cluster has been dubbed the “Phoenix Cluster” because it is located in the constellation of the Phoenix, and because of its remarkable properties.

Stars forming at incredible rates

Like other galaxy clusters, Phoenix holds a vast reservoir of hot gas that contains more normal matter than all of the galaxies in the cluster combined. The reservoir of hot gas can be detected with X-ray telescopes like NASA’s Chandra X-ray Observatory, and the shadow it makes in the light from the big bang can be detected with the South Pole Telescope. The prevailing wisdom had once been that this hot gas should cool over time and sink to the center of the cluster, forming huge numbers of stars.

However, most galaxy clusters have formed very few stars over the last few billion years.

Astronomers think that the supermassive black hole in the central galaxy of clusters pumps energy into the system, preventing cooling of gas from causing a burst of star formation. The famous Perseus Cluster is an example of a black hole bellowing out energy and preventing the gas from cooling to form stars at a high rate.

With its black hole not producing powerful enough jets, the center of the Phoenix Cluster is buzzing with stars that are forming 20 times faster than in the Perseus Cluster. This rate is the highest seen in the center of a galaxy cluster and is comparable to the highest seen anywhere in the universe.

Galaxy clusters contain enough hot gas to create detectable “shadows” in the light left over from the big bang, which also is known as the cosmic microwave background radiation. This light has literally travelled for 14 billion years across the entire observable universe to get to Earth. If it passes through a massive cluster on its way, then a tiny fraction of the light gets scattered to higher energies — the Sunyaev-Zel’dovich effect.

The South Pole Telescope collaboration has now completed an SZ survey of a large region of the sky finding hundreds of distant, massive galaxy clusters. Further follow-up observations of the clusters at X-ray and other wavelengths may reveal the existence of additional Phoenix-like galaxy clusters.

image

Artist’s impression of the galaxy at the center of the Phoenix Cluster.
Courtesy of NASA/CXC/M. Weiss

(via APOD: 2012 July 6 - The Tidal Tail of NGC 3628)
The Tidal Tail of NGC 3628 Image Credit & Copyright: Thomas V. Davis (tvdavisastropix.com)
Trust me on this, you need to see the big version HERE.
It’s possibly the only way you’ll get a good, clear look at the impressive capture that this shot is.
More than just a pretty shot of the Leo Triplet of galaxies (M65, M66, NGC 3628), this is also an impressive capture of the results of galactic gravitational interaction. You can see M65’s (lower-right of group) galactic disc still bent out of shape from various interactions, but most impressive of all is the extended tidal tail of clusters of blue stars coming off the “bottom” edge of NGC 3628. It’s hard to capture and even hard to see in this good capture, so I took the blown-up shot and highlighted it.

Still can’t see it? Click through to the big image above, then move your head to the right of your monitor and look back at the image. (It works even on a flat-panel.)
You might be able to get the same effect by increasing your brightness/contrast controls.
You should see a 300,000 light-year long trail of stars. Yep. About three times as long as the galaxy itself is wide. (NGC 3628 is about the same size as the Milky Way.)

(via APOD: 2012 July 6 - The Tidal Tail of NGC 3628)

The Tidal Tail of NGC 3628 
Image Credit & CopyrightThomas V. Davis (tvdavisastropix.com)

Trust me on this, you need to see the big version HERE.

It’s possibly the only way you’ll get a good, clear look at the impressive capture that this shot is.

More than just a pretty shot of the Leo Triplet of galaxies (M65, M66, NGC 3628), this is also an impressive capture of the results of galactic gravitational interaction. You can see M65’s (lower-right of group) galactic disc still bent out of shape from various interactions, but most impressive of all is the extended tidal tail of clusters of blue stars coming off the “bottom” edge of NGC 3628. It’s hard to capture and even hard to see in this good capture, so I took the blown-up shot and highlighted it.

image

Still can’t see it? Click through to the big image above, then move your head to the right of your monitor and look back at the image. (It works even on a flat-panel.)

You might be able to get the same effect by increasing your brightness/contrast controls.

You should see a 300,000 light-year long trail of stars. Yep. About three times as long as the galaxy itself is wide. (NGC 3628 is about the same size as the Milky Way.)

(via APOD: 2012 June 16 - APOD Turns 17)
Oh. My. Goodness. Click through for the mouse-over. Sunday was the 17th birthday of APOD, which has now served up over a billion images of space and space-related stuff.
This picture is made up of some Hubble Space Telescope shots of galaxies.
Image Credit & Copyright: Judy Schmidt

(via APOD: 2012 June 16 - APOD Turns 17)

Oh. My. Goodness. Click through for the mouse-over. Sunday was the 17th birthday of APOD, which has now served up over a billion images of space and space-related stuff.

This picture is made up of some Hubble Space Telescope shots of galaxies.

Image Credit & Copyright: Judy Schmidt

polymath4ever

M65 and M66

Oh, look, sourcing the photo:
Image Credit & Copyright: Bill Snyder (Heavens Mirror Observatory)
From APOD: http://apod.nasa.gov/apod/ap120615.html
If you’re interested, M65 and M66 are two-thirds of the famous Leo Triplet of galaxies, all of whom are gravitationally interacting with each other, and may have passed through one another at some point in the past.

M65 and M66

Oh, look, sourcing the photo:

Image Credit & Copyright: Bill Snyder (Heavens Mirror Observatory)

From APOD: http://apod.nasa.gov/apod/ap120615.html

If you’re interested, M65 and M66 are two-thirds of the famous Leo Triplet of galaxies, all of whom are gravitationally interacting with each other, and may have passed through one another at some point in the past.

(via The start of a long, long dance | Bad Astronomy | Discover Magazine)
Image credit: Adam Block/Mount Lemmon SkyCenter/University of Arizona
Click through for the big version. Just do it. Or click here:
http://skycenter.arizona.edu/sites/skycenter.arizona.edu/files/n5426.jpg
It’s huuuuge, just a warning.
Anyway, I’ll let this long, slow galactic entanglement between NGC 5426 and NGC 5427 be my g’night piece.
We’ll eventually (in a few million years) be in the middle of one of these ourselves when the Milky Way and Andromeda “collide”. (Not much collides in a galaxy collision except interstellar gas, since stars are usually too far apart to run into each other, though they could get close enough to mess up planetary orbits.)
G’night, tumblr!

(via The start of a long, long dance | Bad Astronomy | Discover Magazine)

Image credit: Adam Block/Mount Lemmon SkyCenter/University of Arizona

Click through for the big version. Just do it. Or click here:

http://skycenter.arizona.edu/sites/skycenter.arizona.edu/files/n5426.jpg

It’s huuuuge, just a warning.

Anyway, I’ll let this long, slow galactic entanglement between NGC 5426 and NGC 5427 be my g’night piece.

We’ll eventually (in a few million years) be in the middle of one of these ourselves when the Milky Way and Andromeda “collide”. (Not much collides in a galaxy collision except interstellar gas, since stars are usually too far apart to run into each other, though they could get close enough to mess up planetary orbits.)

G’night, tumblr!