Posts Tagged galaxies
Beautiful Spiral
A lovely spiral galaxy for your Wednesday.
From our vantage point in the Milky Way Galaxy, we see NGC 6946 face-on. The big, beautiful spiral galaxy is located just 10 million light-years away, behind a veil of foreground dust and stars in the high and far-off constellation of Cepheus. From the core outward, the galaxy’s colors change from the yellowish light of old stars in the center to young blue star clusters and reddish star forming regions along the loose, fragmented spiral arms. NGC 6946 is also bright in infrared light and rich in gas and dust, exhibiting a high star birth and death rate. In fact, since the early 20th century at least nine supernovae, the death explosions of massive stars, were discovered in NGC 6946. Nearly 40,000 light-years across, NGC 6946 is also known as the Fireworks Galaxy. This remarkable portrait of NGC 6946 is a composite that includes image data from the 8.2 meter Subaru Telescope on Mauna Kea.
Composite Image Data – Subaru Telescope (NAOJ) and Robert Gendler; Processing – Robert Gendler
Warped Galaxy
Image courtesy ESA/NASA
I thought I scheduled this post already — I guess I just thought about it REALLY LOUDLY. Saw this image on National Geographic, get a big version on the ESA Hubble website.
A galaxy slightly smaller than our own Milky Way is getting its arm twisted, and a cosmic bully may be to blame.
As seen in a picture released in August by scientists with the NASA/ESA Hubble Space Telescope, one of galaxy NGC 2146′s arms is bent at a 45-degree angle, such that the dense limb has looped in front of the galaxy’s core, as seen from Earth.
The most likely explanation is that the gravity of an unidentified nearby galaxy is disturbing NGC 2146′s arm, causing the galaxy to warp.
Holiday Wreath
I suppose one could construe that most spiral galaxies resemble holiday wreaths, but this is a particularly sparkly, full wreath. So there. Enjoy your Wednesday — and the shortest day of the year!
Resembling festive lights on a holiday wreath, this NASA/ESA Hubble Space Telescope image of the nearby spiral galaxy M74 is an iconic reminder of the impending season. Bright knots of glowing gas light up the spiral arms, indicating a rich environment of star formation.
Messier 74, also called NGC 628, is a stunning example of a grand-design spiral galaxy that is viewed by Earth observers nearly face-on. Its perfectly symmetrical spiral arms emanate from the central nucleus and are dotted with clusters of young blue stars and glowing pink regions of ionized hydrogen (hydrogen atoms that have lost their electrons). These regions of star formation show an excess of light at ultraviolet wavelengths.
Tracing along the spiral arms are winding dust lanes that also begin very near the galaxy’s nucleus and follow along the length of the spiral arms. M74 is located roughly 32 million light-years away in the direction of the constellation Pisces, the Fish. It is the dominant member of a small group of about half a dozen galaxies, the M74 galaxy group. In its entirety, it is estimated that M74 is home to about 100 billion stars, making it slightly smaller than our Milky Way.
Image Credit: NASA, ESA, and the Hubble Heritage (STScI/AURA)-ESA/Hubble Collaboration
Triangulum Core
M33 Triangulum Galaxy Down To The Core, photo by Terry Hancock
A gorgeous galactic core by Terry Hancock!
M33 is a spiral galaxy at approximately 3 million light years distance in the constellation Triangulum. It is catalogued as Messier 33 or NGC 598, and is sometimes informally referred to as the Pinwheel Galaxy, a moniker it shares with Messier 101. The Triangulum Galaxy is a member of the Local Group of galaxies, which includes the Milky Way Galaxy, the Andromeda Galaxy and about 30 other smaller galaxies
Andromeda
The Andromeda Galaxy M31 NGC224, photo © Terry Hancock
This image of M31, the Andromeda Galaxy, is another stunning capture by Terry Hancock (who was shortlisted for the Astronomy Photographer of the Year 2011 award!)
Drifting through the cosmos a mere two and a half million light-years distant, the Andromeda Galaxy is the most voluminous of the galaxies in the Local Group, which includes our own Milky Way galaxy. Visible
to the unaided eye in a dark location, the central core can be seen as a tiny smudge. In a moderate telescope, M31 can be seen with its two largest satellite galaxies; M32 and M110.Located in its namesake constellation, Andromeda contains roughly a trillion stars not including the 14 known satellite galaxies gravitationally bound to it.
Visible in this photograph are the dusty lanes of stellar debris visible as the dark bands. The remnants of stellar deaths, this material will be recycled into new stars and planets as gravitational forces compress the matter within the chaotic environment.
Also visible is the bright central core. Inhabiting the center of M31 is a super-massive black hole responsible for the increase in the density of stars, interstellar gasses, and dust. In this region, temperatures soar and cause the dust and gas to glow in visible wavelengths obscuring the innermost region.
M31 and our own Milky Way Galaxy are on a collision course. Expected to collide in roughly four and a half billion years, it should certainly provide a spectacular show for anyone around to witness its approach.
Galaxy in a Bubble
Image Credit & Copyright: R Jay Gabany (Blackbird Obs.), Collaboration: David Martinez-Delgado (MPIA, IAC), et al.
Definitely one of the more amazing galaxy photos I’ve come across recently. Enjoy your Friday!
Gorgeous spiral galaxy NGC 3521 is a mere 35 million light-years away, toward the constellation Leo. Relatively bright in planet Earth’s sky, NGC 3521 is easily visible in small telescopes but often overlooked by amateur imagers in favor of other Leo spiral galaxies, like M66 and M65. Its hard to overlook in this colorful cosmic portrait, though. Spanning some 50,000 light-years the galaxy sports characteristic patchy, irregular spiral arms laced with dust, pink star forming regions, and clusters of young, blue stars. Remarkably, this deep image also finds NGC 3521 embedded in gigantic bubble-like shells. The shells are likely tidal debris, streams of stars torn from satellite galaxies that have undergone mergers with NGC 3521 in the distant past.
Jet Streams
Credit: ESO/WFI (visible); MPIfR/ESO/APEX/A. Weiss et al. (microwave); NASA/CXC/CfA/R. Kraft et al. (X-ray); Inset: NASA/TANAMI/C. Müller et al. (radio)
Hubble unveiled some amazing time-lapse videos of supersonic jets released by young stars this week; above are some (scary) plasma jets shooting out of a galaxy. I don’t know what this has to do with Labor Day weekend, but here you go anyway. Enjoy.
Jets of streaming plasma expelled by the central black hole of a massive spiral galaxy light up this composite image of Centaurus A. The jets emanating from Cen A are over a million light years long. Exactly how the central black hole expels infalling matter is still unknown. After clearing the galaxy, however, the jets inflate large radio bubbles that likely glow for millions of years. If excited by a passing front, radio bubbles can even light up again after a billion years. X-ray light is depicted in the above composite image in blue, while microwave light is false-colored orange. The inset image in radio light shows newly imaged, never seen-before details of the innermost light year of the central jet.
Cosmic Blender
Image Credit & Copyright: P.-A. Duc (CEA, CFHT), Atlas 3D Collaboration
An interesting image, to be sure. Happy Friday!
What’s happening to galaxy NGC 474? The multiple layers of emission appear strangely complex and unexpected given the relatively featureless appearance of the elliptical galaxy in less deep images. The cause of the shells is currently unknown, but possibly tidal tails related to debris left over from absorbing numerous small galaxies in the past billion years. Alternatively the shells may be like ripples in a pond, where the ongoing collision with the spiral galaxy just above NGC 474 is causing density waves to ripple though the galactic giant. Regardless of the actual cause, the above image dramatically highlights the increasing consensus that at least some elliptical galaxies have formed in the recent past, and that the outer halos of most large galaxies are not really smooth but have complexities induced by frequent interactions with — and accretions of — smaller nearby galaxies. The halo of our own Milky Way Galaxy is one example of such unexpected complexity. NGC 474 spans about 250,000 light years and lies about 100 million light years distant toward the constellation of the Fish (Pisces).
Overlapping
Credit: Hubble Legacy Archive, ESA, NASA; Processing - Martin Pugh
I can’t quite decide what this looks like. Some sort of winged creature? A UFO (complete with antenna up-top?) Two overlapping galaxies (for the imaginatively-challenged?) You decide!
NGC 3314 is actually two large spiral galaxies which just happen to almost exactly line up. The foreground spiral is viewed nearly face-on, its pinwheel shape defined by young bright star clusters. But against the glow of the background galaxy, dark swirling lanes of interstellar dust appear to dominate the face-on spiral’s structure. The dust lanes are surprisingly pervasive, and this remarkable pair of overlapping galaxies is one of a small number of systems in which absorption of light from beyond a galaxy’s own stars can be used to directly explore its distribution of dust. NGC 3314 is about 140 million light-years (background galaxy) and 117 million light-years (foreground galaxy) away in the multi-headed constellation Hydra. The background galaxy would span nearly 70,000 light-years at its estimated distance. A synthetic third channel was created to construct this dramatic new composite of the overlapping galaxies from two color image data in the Hubble Legacy Archive.
Sleeping Beauty
I love the mixture of dark and light in this beautiful image of M64, the Sleeping Beauty Galaxy. (I also love the name, though I can’t find any information on why it’s called that.)
The Sleeping Beauty galaxy may appear peaceful at first sight but it is actually tossing and turning. In an unexpected twist, recent observations have shown that the gas in the outer regions of this photogenic spiral is rotating in the opposite direction from all of the stars! Collisions between gas in the inner and outer regions are creating many hot blue stars and pink emission nebula. The above image was taken by the Hubble Space Telescope in 2001 and released in 2004. The fascinating internal motions of M64, also cataloged as NGC 4826, are thought to be the result of a collision between a small galaxy and a large galaxy where the resultant mix has not yet settled down.
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About Silver Rockets
This blog celebrates space exploration, human spaceflight and the heavens, through lots and lots ofimages.
My name is Danielle Signor, and I am a space cadet. STS-133 NASA Tweetup Attendee!
This is a blog, NOT A SHOP. Click the images for their source or purchase link, if available.
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