StarStuff
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About Me
Hi, I'm Stuart Gary, I'm a journalist and broadcaster with the Australian Broadcasting Corporation. I love science, especially the majesty and wonder of space, so I put together a weekly astronomy show for the ABC called StarStuff.
In my spare time I like to fly planes, practice karate and pistol target shooting and play around with my cars, a twin Turbocharged Falcon GT Interceptor and a DeTomaso Pantera GTS.
I’m vegan, a life member of the RSPCA and a supporter of several animal welfare organisations.
My other great passion is music which is understandable when you realise that I was a radio music jock long before I became a journalist. My record library contains tens of thousands of singles, albums, videos, CD’s and DVDs. These days that’s all stored in an 8 terabyte raid enclosure linked to a desk top PC at home. My tastes range from rock and grunge through to trance and new romantics. At the moment I’m listening to heaps of MGMT, William Control, Hawthorne Heights and Short Shack, but I have lots of time for the classics like Placebo and the early stuff from Silverchair, In fact Neon Ballroom is still my favourite album, and Emotion Sickness is still one of my two favourite songs (the other being William Control’s Death Club).
StarStuff is a great name for the show, but it works on more levels than just astronomy, it’s really cool for any science program because everything in the universe after the quark gluon plasma of the big bang is star stuff even the iron which makes your blood red was manufactured in the supernova explosions of stars. Carl Sagan said it best, we are all star stuff.
This blog is designed to allow me to publish all the things which can’t fit into StarStuff. There’s heaps of really interesting stuff out there and only a half hour window for the show, so each week becomes a battle to try and squeeze it all in. This blog lets me do that.
You can check out the show at the offical ABC StarStuff website:
http://www.abc.net.au/science/starstuff/
There's also an official ABC StarStuff Twitter feed: @abcstarstuff
And an official ABC Science website: http://www.abc.net.au/science/
The legal stuff: This is my personal blog. The views expressed in this blog are those of me only and not the Australian Broadcasting Corporation or its management. I do not claim ownership of any of the media in this blog. where possible credit and or source will always be given. If one of your photos or other media is submitted in this blog and you would like it removed please let me know.
Blogs I follow:
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![CELESTIAL TAPESTRY IS BORN OF UNCERTAIN PARENTAGE
** Summary: A new Legacy Image from the Gemini Observatory reveals the remarkable complexity of the planetary nebula Sharpless 2-71 (Sh 2-71). Embroiled in a bit of controversy over its “birth parents” the nebula likely resulted from interactions between a pair of two old and dying stars. Legacy images like this one share the stunning beauty of the universe as revealed by the twin 8-meter Gemini telescopes in Hawai’i and Chile. **
Often what seems obvious isn’t.
Take this new Gemini Legacy Image of the elaborate planetary nebula Sharpless 2-71. For most of its recorded history, astronomers assumed that it formed from the death throes of an obvious bright star (a known binary system) near its center. Arguments against that claim, however, have turned this case into a classic mystery of uncertain parentage.
The Gemini Legacy Image shows the long-assumed central star shining as the brightest object very close to the center of the nebula’s beautiful gas shell. But new observations have shown that the nature of a dimmer, bluer star — just to the right, and a bit lower than the obvious central star — might provide a better fit for the nebula’s “birth parent.”
The uncertainty arises from the fact that the brighter central star doesn’t appear to radiate enough high-energy (ultraviolet) light to cause the surrounding gas to glow as intensely as it does, whereas the dimmer, bluer star likely does. On the other hand, the brighter star’s binary nature would help explain the nebula’s asymmetrical structure. Astronomers do not yet known if the dimmer, bluer star also has a companion.
Another unresolved issue is whether the brighter star’s unseen companion might be hot enough to excite the gas to glow. If so, this pair might be able to hold on to its parental connection to the nebula.
A research team, led by Australian astronomers David Frew and Quentin Parker (Macquarie University, Sydney) are studying the dimmer, bluer star to understand its nature. “At the assumed distance to the nebula (roughly 1 kiloparsec, or about 3,260 light-years), the faint star has about the right brightness to be the fading remnant of the nebula’s progenitor star,” says Frew.
Then again, the brighter binary star is an uncommon one that shows strong and broad hydrogen-alpha emission, which are seen in some planetary nebulae. According to Frew, this star is also unlikely to be a chance projection or alignment with the nebula, “So there could be at least three stars in this system,” he says.
Putting aside the complex issue of which star or stars formed this object, the nebula’s striking morphology also poses difficult questions. “The nebula presents a multi-polar structure and several pairs of bipolar lobes at different orientations,” says Luis Miranda of Spain’s Instituto de Astrofísica de Andalucía (CSIC) who has also studied this object extensively. “These lobes most certainly formed at different times and likely involved a binary progenitor — in particular with mass-transfer and multiple episodes of mass ejection along an axis where the orientation changes with time.”
Adding to the puzzle, Parker and Romano Corradi (Instituto de Astrofisica de Canarias, Spain) have recently discovered faint outer wisps and lobes surrounding the planetary on deep hydrogen-alpha images, taken as part of the Isaac Newton Telescope Photometric Hydrogen Alpha Survey of the Northern Galactic Plane Survey. These features extend over many arcminutes (not shown in the new Gemini image), suggesting the mass loss history of this object has even more levels of complexity.
Miranda agrees, noting that the nebula’s structure is difficult to explain without a binary pair for parents. “The chaotic morphology of Sh 2-71 implies that very complex processes have been involved in its formation,” says Miranda. Unfortunately, not much is known about either possible central star’s known or speculated companions. So the mystery of the nebula’s uncertain parentage remains unsolved…for now.
IMAGE….Gemini Legacy image of the complex planetary nebula Sh2-71 as imaged by the Gemini Multi-Object Spectrograph on Gemini North on Mauna Kea in Hawai‘i. The long-assumed central star is the brightest star near the center, but some astronomers wonder if the much dimmer and bluer star (just to the right and down a bit) might be the parent of this beautiful object. The image is composed of three narrow-band images, and each is assigned a color as follows: H-alpha (orange), HeII (blue) and [OIII] (cyan). Each image is 15 minutes in duration, the field-of-view is 5.3 x 3.6 arcminutes, and the image is rotated 110 degrees clockwise from north up, east left.
Image credit: Gemini Observatory/AURA](http://25.media.tumblr.com/tumblr_m55at13qLV1qg9lvdo1_500.jpg)
CELESTIAL TAPESTRY IS BORN OF UNCERTAIN PARENTAGE
** Summary: A new Legacy Image from the Gemini Observatory reveals the remarkable complexity of the planetary nebula Sharpless 2-71 (Sh 2-71). Embroiled in a bit of controversy over its “birth parents” the nebula likely resulted from interactions between a pair of two old and dying stars. Legacy images like this one share the stunning beauty of the universe as revealed by the twin 8-meter Gemini telescopes in Hawai’i and Chile. **
Often what seems obvious isn’t.
Take this new Gemini Legacy Image of the elaborate planetary nebula Sharpless 2-71. For most of its recorded history, astronomers assumed that it formed from the death throes of an obvious bright star (a known binary system) near its center. Arguments against that claim, however, have turned this case into a classic mystery of uncertain parentage.
The Gemini Legacy Image shows the long-assumed central star shining as the brightest object very close to the center of the nebula’s beautiful gas shell. But new observations have shown that the nature of a dimmer, bluer star — just to the right, and a bit lower than the obvious central star — might provide a better fit for the nebula’s “birth parent.”
The uncertainty arises from the fact that the brighter central star doesn’t appear to radiate enough high-energy (ultraviolet) light to cause the surrounding gas to glow as intensely as it does, whereas the dimmer, bluer star likely does. On the other hand, the brighter star’s binary nature would help explain the nebula’s asymmetrical structure. Astronomers do not yet known if the dimmer, bluer star also has a companion.
Another unresolved issue is whether the brighter star’s unseen companion might be hot enough to excite the gas to glow. If so, this pair might be able to hold on to its parental connection to the nebula.
A research team, led by Australian astronomers David Frew and Quentin Parker (Macquarie University, Sydney) are studying the dimmer, bluer star to understand its nature. “At the assumed distance to the nebula (roughly 1 kiloparsec, or about 3,260 light-years), the faint star has about the right brightness to be the fading remnant of the nebula’s progenitor star,” says Frew.
Then again, the brighter binary star is an uncommon one that shows strong and broad hydrogen-alpha emission, which are seen in some planetary nebulae. According to Frew, this star is also unlikely to be a chance projection or alignment with the nebula, “So there could be at least three stars in this system,” he says.
Putting aside the complex issue of which star or stars formed this object, the nebula’s striking morphology also poses difficult questions. “The nebula presents a multi-polar structure and several pairs of bipolar lobes at different orientations,” says Luis Miranda of Spain’s Instituto de Astrofísica de Andalucía (CSIC) who has also studied this object extensively. “These lobes most certainly formed at different times and likely involved a binary progenitor — in particular with mass-transfer and multiple episodes of mass ejection along an axis where the orientation changes with time.”
Adding to the puzzle, Parker and Romano Corradi (Instituto de Astrofisica de Canarias, Spain) have recently discovered faint outer wisps and lobes surrounding the planetary on deep hydrogen-alpha images, taken as part of the Isaac Newton Telescope Photometric Hydrogen Alpha Survey of the Northern Galactic Plane Survey. These features extend over many arcminutes (not shown in the new Gemini image), suggesting the mass loss history of this object has even more levels of complexity.
Miranda agrees, noting that the nebula’s structure is difficult to explain without a binary pair for parents. “The chaotic morphology of Sh 2-71 implies that very complex processes have been involved in its formation,” says Miranda. Unfortunately, not much is known about either possible central star’s known or speculated companions. So the mystery of the nebula’s uncertain parentage remains unsolved…for now.
IMAGE….Gemini Legacy image of the complex planetary nebula Sh2-71 as imaged by the Gemini Multi-Object Spectrograph on Gemini North on Mauna Kea in Hawai‘i. The long-assumed central star is the brightest star near the center, but some astronomers wonder if the much dimmer and bluer star (just to the right and down a bit) might be the parent of this beautiful object. The image is composed of three narrow-band images, and each is assigned a color as follows: H-alpha (orange), HeII (blue) and [OIII] (cyan). Each image is 15 minutes in duration, the field-of-view is 5.3 x 3.6 arcminutes, and the image is rotated 110 degrees clockwise from north up, east left.
Image credit: Gemini Observatory/AURA
