Astronomy Picture of the Day

Radiate_Truth · Joined: 18 Aug 2007 Posts: 1056

M78: Stardust and Starlight

Interstellar dust clouds and bright nebulae abound in the fertile constellation of Orion.

One of the brightest, M78, is just below center in this sharp widefield view, covering an area north of Orion's belt.

At a distance of about 1,500 light-years, the bluish nebula itself is about 5 light-years across.

Its blue tint is due to dust preferentially reflecting the blue light of hot, young stars in the region.

Dark dust lanes and other nebulae can easily be traced through this gorgeous skyscape that also includes the remarkable McNeil's Nebula -- a newly recognized nebula associated with the formation of a sun-like star.

Supernova Remnant N132D in Optical and X Rays

Thousands of years after a star exploded, its expanding remnant still glows brightly across the spectrum.

Such is the case with N132D, a supernova remnant located in the neighboring Large Magellanic Cloud (LMC) galaxy.

The expanding shell from this explosion now spans 80 light-years and has swept up about 600 Suns worth of mass.

N132D was imaged recently in optical light and in great detail with the Hubble Space Telescope.

The Hubble image was then combined with a position coincident detailed image in X-ray light taken by the Chandra X-ray Observatory.

The combination, shown above in representative colors, shows a nearly spherical expanding shockwave highlighted by pink emission from hydrogen gas and purple emission from oxygen gas.

A dense field of unrelated stars also from the LMC populates the image.

Studying the image gives an opportunity to study material once hidden deep inside a star.

N132D spans about 150 light years and lies about 160,000 light years away toward the constellation of Dorado.

Ring Galaxy AM 0644-741 from Hubble

How could a galaxy become shaped like a ring?

The rim of the blue galaxy pictured on the right is an immense ring-like structure 150,000 light years in diameter composed of newly formed, extremely bright, massive stars.

That galaxy, AM 0644-741, is known as a ring galaxy and was caused by an immense galaxy collision.

When galaxies collide, they pass through each other -- their individual stars rarely come into contact.

The ring-like shape is the result of the gravitational disruption caused by an entire small intruder galaxy passing through a large one.

When this happens, interstellar gas and dust become condensed, causing a wave of star formation to move out from the impact point like a ripple across the surface of a pond.

The intruder galaxy has since moved out of the frame taken by the Hubble Space Telescope and released to commemorate the anniversary of Hubble's launch in 1990.

Ring galaxy AM 0644-741 lies about 300 million light years away.

AE Aurigae: The Flaming Star

Is star AE Aurigae on fire?

No.

Even though AE Aurigae is named the flaming star, the surrounding nebula IC 405 is named the Flaming Star Nebula, and the region appears to harbor red smoke, there is no fire.

Fire, typically defined as the rapid molecular acquisition of oxygen, happens only when sufficient oxygen is present and is not important in such high-energy, low-oxygen environments such as stars.

The material that appears as smoke is mostly interstellar hydrogen, but does contain smoke-like dark filaments of carbon-rich dust grains.

The bright star AE Aurigae, visible just below the image center, is so hot it is blue, emitting light so energetic it knocks electrons away from surrounding gas.

When a proton recaptures an electron, red light is frequently emitted, as seen in the surrounding emission nebula.

Pictured above, the Flaming Star nebula lies about 1,500 light years distant, spans about 5 light years, and is visible with a small telescope toward the constellation of the Charioteer (Auriga).

Alnitak, Alnilam, Mintaka

Alnitak, Alnilam, and Mintaka, are the bright bluish stars from east to west (left to right) along the diagonal in this gorgeous cosmic vista.

Otherwise known as the Belt of Orion, these three blue supergiant stars are hotter and much more massive than the Sun.

They lie about 1,500 light-years away, born of Orion's well-studied interstellar clouds.

In fact, clouds of gas and dust adrift in this region have intriguing and some surprisingly familiar shapes, including the dark Horsehead Nebula and Flame Nebula near Alnitak at the lower left.

The famous Orion Nebula itself lies off the bottom of this star field that covers an impressive 4.4x3.5 degrees on the sky.

The color picture was composited from digitized black and white photographic plates recorded through red and blue astronomical filters, with a computer synthesized green channel.

The plates were taken using the Samuel Oschin Telescope, a wide-field survey instrument at Palomar Observatory, between 1987 and 1991.

NGC 7635: The Bubble Nebula
Credit & Copyright: Russell Croman

Explanation: It's the bubble versus the cloud. NGC 7635, the Bubble Nebula, is being pushed out by the stellar wind of massive central star BD+602522. Next door, though, lives a giant molecular cloud, visible above to the lower right. At this place in space, an irresistible force meets an immovable object in an interesting way. The cloud is able to contain the expansion of the bubble gas, but gets blasted by the hot radiation from the bubble's central star. The radiation heats up dense regions of the molecular cloud causing it to glow. The Bubble Nebula, pictured above in scientifically mapped colors to bring up contrast, is about 10 light-years across and part of a much larger complex of stars and shells. The Bubble Nebula can be seen with a small telescope towards the constellation of Cassiopeia.

Aurora from Space
Credit: Don Pettit, ISS Expedition 6, NASA

Explanation: From the ground, spectacular auroras seem to dance high above. But the International Space Station (ISS) orbits at nearly the same height as many auroras, sometimes passing over them, and sometimes right through them. Still, the auroral electron and proton streams pose no direct danger to the ISS. In 2003, ISS Science Officer Don Pettit captured the green aurora, pictured above in a digitally sharpened image. From orbit, Pettit reported that changing auroras appeared to crawl around like giant green amoebas. Over 300 kilometers below, the Manicouagan Impact Crater can be seen in northern Canada, planet Earth.

A Soyuz Spacecraft Approaches the Space Station
Credit : ISS Expedition 11 Crew, NASA

Explanation: Last month, a Soyuz TMA-7 spacecraft docked with the International Space Station. The spacecraft was launched a few days earlier from the Baikonur Cosmodrome in Kazakhstan. Pictured above, the approaching Soyuz spacecraft carried the new Expedition 12 crew to the Earth-orbiting International Space Station (ISS), as well as fee-paying spaceflight participant. The Expedition 12 crew is expected to stay on the ISS for about six months, while replacing the Expedition 11 crew who had been on the station for about six months themselves. About a week after this image was taken, the Expedition 11 crew returned to Earth in the Soyuz capsule, along with the spaceflight participant. The Expedition 12 crew will carry out repairs on the ISS, explore new methods of living in space, and conduct research in space including a kidney stone experiment.

A Dark and Stormy Night
Credit : T. Credner & S. Kohle, AlltheSky.com

Explanation: It was a dark and stormy night. But on 2003 August 29th the red planet Mars, near its closest approach to Earth in almost 60,000 years, shone brightly in the sky against a background of stars in the constellation Aquarius. In the foreground of this scary view, huge thunder clouds are lit by lightning strokes from within. Mars, of course, has nothing to do with storms on Earth, though both have the power to excite the imagination and wonder of Earthdwellers. Tonight, the night before Halloween, Mars will also pass close to the Earth, closer than it will come during the next thirteen years. And once again, the red planet Mars will look particularly bright, although much smaller and dimmer than the Moon and even Venus.

The Last Titan
Credit : Courtesy 30th Space Wing, Vandenberg Air Force Base

Explanation: On October 19th, a rocket blasted off from Vandenberg Air Force Base - the last Titan rocket. Carrying a payload for the US National Reconnaissance Office, the successful Titan IV B launch brings to a close the Titan program whose first launch was in 1959. Originally designed as an intercontinental ballistic missile, the Titan rocket ultimately evolved into a heavy lift workhorse, launching defense, commercial, and scientific payloads to Earth orbit and beyond. In fact, many historic space explorations began with Titan launches, including manned Gemini missions, the Viking missions to Mars, the Voyager tours of the outer solar system, and the Cassini spacecraft now orbiting Saturn. Cassini's probe Huygens accomplished the most distant landing on another world, while Voyager 1 is now humanity's most distant spacecraft.

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obmar · Site Admin Joined: 14 Apr 2006 Posts: 5697

Thanks RT.

One can just be at awe at the total size of God's Creatuon.

In the total creation the earth is nor even the size of a minute dusk particle.

So what is a human being then?

Radiate_Truth · Joined: 18 Aug 2007 Posts: 1056

No more than a mere molecule or atom with a individual character all it's own. That makes each of each special as individuals. Not being exactly or even close to identical.

The Inquisitor · Joined: 17 Jun 2006 Posts: 772

Very pretty, RT.

I've only seen a few of those pictures before. They are outstanding, especially the one about the Aurora Borealis.

Radiate_Truth · Joined: 18 Aug 2007 Posts: 1056

Aurora Borealis...one of my very favorites.

Something like 60 people die everyday in third world countries from starvation. The sad thing tho' is the trillions of dollars we spend going into outer space. Yet, why can't never seem to find enough money to cure the sick, food the hungry and give shelter to the homeless.

Rachel

jhoneferis · Joined: 09 Nov 2009 Posts: 4

Hi..
Nice snap shots.. Thanks for sharing the information..
_________________
r4 card

obmar · Site Admin Joined: 14 Apr 2006 Posts: 5697

obmar · Site Admin Joined: 14 Apr 2006 Posts: 5697