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Most recent 19 results returned for keyword: Main Sequence (Search this on MAP)

https://plus.google.com/114252689252829608094 victorina rousseau : Star formation in the Chamaeleon Complex In this near-infrared mosaic image taken by the Hubble Space...
Star formation in the Chamaeleon Complex

In this near-infrared mosaic image taken by the Hubble Space Telescope and processed by Judy Schmidt (Geckzilla) you can see the Chamaeleon I dark cloud in the Chamaeleon complex. It is a star-forming (https://goo.gl/Mn2Zxf) region of space, located in the constellation of Chamaeleon (The Chameleon, https://goo.gl/diyXtC), about 400 to 700 light-years away from Earth.

Take a look at the beautiful, wispy clouds of dust visible in this infrared image. The dust is the fuel for star formation in the region.

The bright star a little to the right and top of the center of the image is DI Chamaeleontis (HIP 54365, https://goo.gl/L4A5dp), which is actually a quadruple star system, consisting of two close binary star systems (https://goo.gl/U5Tids). Take a closer look at it in this image: https://flic.kr/p/dgRTU2

A little to the left and bottom of the center of the image you can find CU Chamaeleontis (HD 97048, https://goo.gl/8PnCdQ), a bluish A-type main-sequence star (https://goo.gl/lG0Vas).

Make sure to look at the full-size version of this image on Judy's Flickr!

More information here:
https://flic.kr/p/QPnZrf
https://en.wikipedia.org/wiki/Chamaeleon_complex

Diffraction spikes

In the image you can see stars with very pronounced spikes in the form of a cross. These spikes are called diffraction spikes and are caused by the struts that support Hubble's secondary mirror (https://goo.gl/zFd42g). The light is being diffracted around those support struts, generating the cross-formed spikes. They are only visible around point sources where a lot of light is concentrated in one small spot. Read more on it here:
https://en.wikipedia.org/wiki/Diffraction_spike

Image credit: Chamaeleon complex Image processed by Judy Schmidt based on Hubble and DSS data https://flic.kr/p/QPnZrf CC BY 2.0 https://goo.gl/sZ7V7x

Take a look at more of her work here:

I recommend you take a look at her website http://geckzilla.com/ and her Flickr https://www.flickr.com/photos/geckzilla/ to see more of the many beautiful images Judy processed. You can also find her on Twitter: https://twitter.com/SpaceGeck

Thank you for your interest in this Astronomy/Astrophysics collection. Maybe add me on Google+ (+Pierre Markuse) and Twitter (https://twitter.com/Pierre_Markuse) or have a look at the Space/Space Technology collection here: https://goo.gl/5KP0wx

#science #astronomy #astrophysics #starformation #Chamaeleon #Chamaeleoncomplex #dust #infraredastronomy #hubble #hst #dss #space
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https://plus.google.com/114794709005836059652 sudesh paul : Life cycles of stars A star's life cycle is determined by its mass. The larger its mass, the shorter...
Life cycles of stars
A star's life cycle is determined by its mass. The larger its mass, the shorter its life cycle. A star's mass is determined by the amount of matter that is available in its nebula, the giant cloud of gas and dust from which it was born. Over time, the hydrogen gas in the nebula is pulled together by gravity and it begins to spin.

As the gas spins faster, it heats up and becomes as a protostar. Eventually the temperature reaches 15,000,000 degrees and nuclear fusion occurs in the cloud's core. The cloud begins to glow brightly, contracts a little, and becomes stable. It is now a main sequence star and will remain in this stage, shining for millions to billions of years to come. This is the stage our Sun is at right now.
 
As the main sequence star glows, hydrogen in its core is converted into helium by nuclear fusion. When the hydrogen supply in the core begins to run out, and the star is no longer generating heat by nuclear fusion, the core becomes unstable and contracts. The outer shell of the star, which is still mostly hydrogen, starts to expand. As it expands, it cools and glows red. The star has now reached the red giant phase. It is red because it is cooler than it was in the main sequence star stage and it is a giant because the outer shell has expanded outward. In the core of the red giant, helium fuses into carbon.

All stars evolve the same way up to the red giant phase. The amount of mass a star has determines which of the following life cycle paths it will take from there.

For low mass stars, after the helium has fused into carbon, the core collapses again. As the core collapses, the outer layers of the star are expelled. A planetary nebula is formed by the outer layers. The core remains as a white dwarf and eventually cools to become a black dwarf.

High mass stars are born in nebulae and evolve and live in the Main Sequence. However their life cycles start to differ after the red giant phase. A massive star will undergo a supernova explosion. If the remnant of the explosion is 1.4 to about 3 times as massive as our Sun, it will become a neutron star. The core of a massive star that has more than roughly 3 times the mass of our Sun after the explosion will do something quite different. The force of gravity overcomes the nuclear forces which keep protons and neutrons from combining. The core is thus swallowed by its own gravity. It has now become a black hole which readily attracts any matter and energy that comes near it.

What happens between the red giant phase and the supernova explosion?
Once stars that are 5 times or more massive than our Sun reach the red giant phase, their core temperature increases as carbon atoms are formed from the fusion of helium atoms. Gravity continues to pull carbon atoms together as the temperature increases and additional fusion processes proceed, forming oxygen, nitrogen, and eventually iron.

When the core contains essentially just iron, fusion in the core ceases. This is because iron is the most compact and stable of all the elements. It takes more energy to break up the iron nucleus than that of any other element. Creating heavier elements through fusing of iron thus requires an input of energy rather than the release of energy. Since energy is no longer being radiated from the core, in less than a second, the star begins the final phase of gravitational collapse. The core temperature rises to over 100 billion degrees as the iron atoms are crushed together. The repulsive force between the nuclei overcomes the force of gravity, and the core recoils out from the heart of the star in a shock wave, which we see as a supernova explosion.

References:
http://www.schoolsobservatory.org.uk/astro/stars/lifecycle
http://www.telescope.org/pparc/res8.html
https://imagine.gsfc.nasa.gov/educators/lessons/xray_spectra/background-lifecycles.html

#universe   #space   #stars   #science    #nasa  
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https://plus.google.com/101206844490955510056 Get Set Know : SPACE SCIENCE By Wayne (meet all the characters on Issue 5 of Get, Set, KNOW!) Every one of our readers...
SPACE SCIENCE
By Wayne
(meet all the characters on Issue 5 of Get, Set, KNOW!)

Every one of our readers must have wondered how our alien brothers will look like. Apart from movie and comic illustrations, we will now explore the conditions feasible for earth like alien life to thrive as proposed by scientists.

The right object
On what you are searching for life matters most, you won’t find alien wildlife on a red supergiant star or on Halley’s Comet. Rocky planets and satellites (moons) are best.

The right parent
Imagine the condition of a planet between a binary star system in which usually a red giant and a white dwarf orbit each other, the white dwarf acting as a vacuum cleaner sucking material from the red giant by its enormous gravity. Sun like main sequence yellow dwarfs and red dwarfs are good parents.

Suitable neighborhood
The best planet location is said to be in the Habitable Zone. Habitable Zone refers to intersection of the two locations of the planet, one planetary (such as within our Solar System), and the other galactic.
The planet in this location is (scientifically) called the ‘Goldilocks planet’.
The catch is that some planets have the possibility to sustain life in microenvironments.
However gas giants such as Jupiter can also be in the goldilocks zone, which do not support life.

High Metallicity of parent star
Metallicity of an object in cosmology is basically the proportion of matter consisting of elements other than Hydrogen and Helium. Astronomers collectively used the term ‘metal’ to describe all the other elements. Thus a star with low metal would reduce the chance of planet formation around that particular star.
Mass
Objects with low mass, would have less gravity, and would not be able to retain the life supporting atmosphere. Smaller planets and satellites also tend to lose the energy left after their formation, becoming dead of the geological activity such as volcanic eruptions and tectonic shift which provide the surface with life sustaining biomass. This would also result in continent creation, improving biodiversity.

Less luminosity alteration in star
Although fluctuation luminosity is common to all stars, some stars termed as variable stars experience sudden and intense fluctuations lasting from minutes to years. Changes in luminosity would also be accompanied by high doses of Gamma and X-Ray radiation. Temperature fluctuations, as we know, are not suitable.


Bodyguard
A huge gas giant bodyguard neighbor like our Jupiter would be in fact, good for our candidate in many ways. They have circular orbits, far enough from the habitable zone, to stabilize the orbits and therefore the temperature of the inner terrestrial planets and protect the candidate from comets and meteors.
The gas Giant’s protector role was visualized in 1994 when Comet Shoemaker Levy 9 struck Jupiter. If not for its gravity…, oh… just forget that.

Magnetosphere
The endogenic forces taking place in the molten magma beneath the earth crust work like an enormous heat engine, which keeps the magnetosphere active. The magnetic shield protects life from highly ionized charged alpha particles along with high amounts of Gamma and X ray radiation.

Less eccentricity in orbit

Eccentricity is basically the amount of orbit deviation from a perfect circle. The greater the eccentricity, greater will be the temperature fluctuations. Even with life’s adaptive properties, the freezing and boiling points of the candidate’s primary solvent mostly overlap. Our earth’s orbit is almost circular with less than 0.02 eccentricity.

Tilt in Axis
We all know our planet is a bit tilted (23.5).The advantage of this is that it brings the dynamism and diversity our life holds. And with a significant tilt, the intensity of radiation will be focused only within the equatorial areas, the warmth wouldn’t move poleward and the entire planet would be dominated by colder climates.

Biomass
If we are to find life similar to ours, then we expect it to be based on the same biochemistry as ours, Carbon, Hydrogen, Oxygen and Nitrogen being the most common. The elements in fact, comprise over 96% of Earth’s all biomass. Biogenic compounds, such as amino acids (simple proteins) have been found in meteorites and interstellar mediums.
Carbon is the main basis for earth life, which can bond itself to form complex structures, Hydrogen and Oxygen combine to form the solvent of earth life i.e. water. The energy released by oxidation of organic compounds and formation of strong covalent bonds between Carbon and Oxygen, is the fuel of all living creatures of earth.

Time
Life, being an extremely sophisticated race, takes its time to develop. Humans, as we know them (read ‘ourselves’), came to this stage after a 3.5 billion years of development of life. We also picture the future after 10 or 20 years. Can we even think the rate of development of life?

Intelligent Life
Till now we only discussed about simple life survival conditions. Let’s now extend this idea further. Suppose we find a planet or satellite which is fulfilling all the requirements. So what will be our next step? After all, life and intelligent life are very distinct. If life on a planet has reached the stage of what would be some 2050 on earth? We would positively consider them to be more intelligent, right?
Other than time, a few factors if included would produce the most complex and intelligent species ever imagined by us.

Super earths
A planet which would host such intelligent life would
- Orbit a red dwarf star (which has greatest life among all other stars without any significant size or luminosity fluctuation) and be in between the arms of a galaxy quite far from the centre. (the safest galactic location)
- Be terrestrial, ranging in size from 2 to 5 times larger than our Earth.
- Because it would have greater gravity (due to its size), leading to greater atmospheric retention and stronger magnetosphere.
- It would lack significant tilt and eccentricity.
- Life would have existed for more than 4.5 billion years.

See the original article on Issue 5 of Get, Set, KNOW!
6 hours ago - Via Google+ - View -
https://plus.google.com/108047831070396085293 Scout 107 : other allowed planet: Monetova Species: Karavonians Karvonian attributes: can survive in low gravity...
other allowed planet: Monetova
Species: Karavonians
Karvonian attributes: can survive in low gravity enviroments and can breath CO2.
starting techs: Gamma mirrors (can reflect Gamma rays) , all energy beams, moscovium fission, fission engines, modern computing.
planet: earthlike but has less gravity
surrounding system: 1 yellow main sequence star, 1 hot jupiter near the star, 2 other rocky planets, 1 is 1/2 an au away from the star ad the other is 3 AU away, an asteroid belt between the farthest out rocky planet and a gas giant, there are 3 other ice giants and a kuiper belt in the system, the nearest rocky planet to the sun is an abyssopelagic ocean planet (completely made out of water/no life.

https://lh3.googleusercontent.com/-0nqQuLYdZWA/WIQQBuUjs0I/AAAAAAAADmY/2yERZBDjv9EWdAAjUAK_rFUZ7dke0a8awCJoC/w506-h750/monetova.png
12 hours ago - Via Community - View -
https://plus.google.com/114484261254956518567 Jesus Galvez : Space..A Portrait of Stars.. Messier 83 (M83) is a relatively nearby spiral galaxy with a pronounced...
Space..A Portrait of Stars..
Messier 83 (M83) is a relatively nearby spiral galaxy with a pronounced bar-like structure. It is located in the southern constellation Hydra (The Water-Snake) and is also known as NGC 5236; the distance is approximately 12 million light-years. Images of M83 obtained in visible light - like the VLT photo published exactly two years ago - show clumpy, well-defined spiral arms that are rich in young stars while the disk reveals a complex system of intricate dust lanes. This galaxy is known to be a site of vigorous star formation and no less than six supernovae (exploding stars) have been observed in M83 during the past century. It is a fairly symmetrical object and possesses no nearby companions.

Gas dynamics and galaxy bars

Investigations of gas motions in the nucleus and in the main disk play a key role in understanding the structure and evolution of barred spiral galaxies like M83. Inflow of gas towards the center caused by a mass distribution that is not circularly symmetric is often invoked to explain certain observed phenomena, e.g., the feeding of Active Galactic Nuclei (AGNs, see also the report about recent observations in three such galaxies , and the fueling of bursts of star formation in the nuclear region. Some astronomers think that this process may cause a change of a galaxy's (morphological) type, for instance from barred to normal spiral galaxy.

It has also been suggested that the development of spiral structures in galactic disks may be due to central stellar bars. Interstellar gas that is subject to periodical perturbations by the non-circularly symmetrical gravitational field in a barred system will develop a "density wave" that attracts neighbouring stars and gas. The local density increases and once a certain ("critical") value is reached, star formation is "ignited" in this area.

The mass distribution

In order to better understand phenomena like these, it is essential to know in detail the distribution of matter in the galaxy disk. This is best done by means of infrared observations.

Images obtained in the optical region of the spectrum mainly trace the pattern of star formation as well as young and bright stars, rather than the mass distribution in the galaxy. The regions with much dust are also well visible on such images as dark lanes and clouds, since they are very opaque to visible light. However, on infrared images, the dust absorption is much smaller and the light that is recorded mainly comes from old giant stars. Although those stars contribute little to the mass, they have the same spatial distribution as the much more numerous, smaller ("main sequence") stars. Their distribution therefore shows the mass distribution in the galaxy and hence the gravitation field that directs the motions of the interstellar gas.

New infrared images of Messier 83

It is for this reason that infrared images of barred galaxies, like the ones of M83 shown here that was prepared by a group of Swedish astronomers [1], are extremely useful for the study of the dynamics of such galaxies and their development.

In order to produce these (false-) colour photos, three infrared images of M83 obtained in the Ks- (wavelength 2.2 µm), J- (1.2 µm) and I-bands (0.8 µm), respectively, were combined into one colour image. The field shown in ESO a measures 32,000 light-years across at the distance of M83. The dust lanes appear red since the emission in the longest waveband (Ks) is able to penetrate the dense gas and dust clouds. Note also how the dust lanes follow the leading edge of the bar - assuming that the arms are trailing and that the upper right area is the side of the galaxy that is nearest to us.

Notes

[1] The group includes Andreas Andersson and Hans Olofsson (Stockholm Observatory, SCFAB), and Tommy Wiklind and Gustaf Rydbeck (Onsala Space Observatory). The group is grateful to Søren Larsen for the use of an I-image for the present work.

Credit: ESO

About the Object
Name:M 83, Messier 83, NGC 5236
Type:Local Universe :
Galaxy : Type : Barred
Distance:15 million light years
Constellation:Hydra
Category:Galaxies
https://lh3.googleusercontent.com/-0_ZoNvX_S1U/WIAXWzjoRuI/AAAAAAAAEuE/Ny-Yff7jPOQGiX7PkebCpoq24dpkpqhngCJoC/w506-h750/17%2B-%2B1
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https://plus.google.com/104282589772198168289 REGO G. : Kepler-91b is a planet orbiting Kepler-91, a star slightly more massive than the Sun. Kepler-91 has ...

Kepler-91b is a planet orbiting Kepler-91, a star slightly more massive than the Sun. 
Kepler-91 has left the main sequence and is now a red giant branch star Kepler-91b is about 14% less massive than Jupiter 
while being more than 35% larger, making it less than half of the density of water. Kepler-91b orbits around the host star in 
about 6.25 days. Despite being one of the least edge-on orbits relative to Earth with inclination being about 68.5 degrees, 
transit was detected due to low semi-major axis to host star radius ratio.Kepler-91b is expected to be engulfed by the parent 
star within about 55 million years."Simulation of a dawn"
Watch the video: susnset~1.avi
https://lh3.googleusercontent.com/-MwJWOMxrh2o/VPn-A2vlXkI/AAAAAAAAHQA/WKSncL1gNKc/w506-h379-n-o/susnset%257E1.avi
Kepler-91b is a planet orbiting Kepler-91, a star slightly more massive than the Sun. Kepler-91 has left the main sequence and is now a red giant branch star Kepler-91b is about 14% less massive than Jupiter while being more than 35% larger, making it less than half of the density of water. Kepler-91b orbits around the host star in about 6.25 days. Despite being one of the least edge-on orbits relative to Earth with inclination being about 68.5
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https://plus.google.com/102933808918540227364 Gerry Kichok : In this video you discuss the death of stars like our sun; a main sequence star that burns all it's ...
In this video you discuss the death of stars like our sun; a main sequence star that burns all it's fuel becomes a red giant, blows off a bubble or shell of gas leaving a white dwarf that is old but 'not quite dead' until it cools to become a 'black dwarf' that has the composition of a white dwarf but has gone cold. Correct?

At some point a white dwarf will glow red and then brown but this is in no way the same thing as a red dwarf or brown dwarf star we see today that simply did not have enough matter to burn as bright as our sun. It is composed mostly of hydrogen and maybe helium while a nearly dead white dwarf is composed of much heavier elements like carbon, oxygen or neon left over from the core collapse. I think. I have studied astronomy for years and yet due to new discoveries and my poor memory I'm not sure I'm correct.

Different mass stars all live out their own stellar sequence and ultimately die in many different ways from cold white dwarfs to nova and supernova. I should be able to find this on wiki somewhere.

My question is not about "natural stellar deaths" but rather UNNATURAL STELLAR DEATHS?

Such as twin binary stars in which one star wanders too close to the other and is for lack of a better term is "eaten". Different stellar masses of stars in this "unnatural" death will look quite different when they die. In a recent video I watched about the most bizarre planets found it talked of hot Jupiters and metallic planets that rain metallic elements, a completely black planet (made of carbon?) and the first planets found around a pulsar bathed in x-rays with surfaces of ... I missed that bit ... but my mind quickly wondered about all these bizarre exoplanets and whether or not they where in fact actually planets at all? I'm sure many hot Jupiters are the result of planets wandering in too close to their star but could some of these bizarre exoplanets not be the unnatural death of small stars especially if their composition more closely matches that of white dwarfs and other dead stars simply kept warm now by their stellar partner as their dead stellar bones are all that is left uneaten? Could the planets found around that pulsar not be the scattered bones of a single star that was eaten by living star before it became a pulsar and simply broken apart when it exploded as a supernova? I tried to imagine how much of the earth would be left if our sun was large enough to explode and produce a pulsar or neutron star or even a black hole?

Just as Pluto has be relegated to one of thousands of dwarf planets I think we are going to also think big too as many of these new exoplanets found are large enough and close enough to their star's to ask the question when is a large planet no longer a planet? It cannot be simply a matter of nuclear fusion as dead stars are never call planets ever again until they are reborn out of "dust" circling a new star?

Or am I just splitting hairs?
Watch the video: Black Dwarf Stars: Corpses of Creation
https://lh3.googleusercontent.com/proxy/vRF1eQdEeIs5HsydGJ2S6mMilKdZr74OxWWPaL9B55FmIVWq4sgj_4kn2vqZR5_D0FDUaOihCwLMMNoC0yxKmbyFfes=w506-h284-n
Original Music Available from Stephen Dubois: http://www.ancienteyesmusic.com This space documentary was inspired by conversations with Space Fans from Patre...
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https://plus.google.com/116966329976379654431 Scarlette Genger : https://www.youtube.com/shared?ci=letaXTwTf18 She wanted a love that was real, a love she didn't have...
https://www.youtube.com/shared?ci=letaXTwTf18

She wanted a love that was real, a love she didn't have to fight for a love that would never leave so , she decided to be true to herself, love herself and solitude unconditionally. She realized all she needed was herself.
#freedom #selfknowledge #solitation=elevation #woke
Main Sequence - Progress (The Ownership Society) - YouTube
Scarlette Genger shared a video
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https://plus.google.com/111680909852262112974 Ray Junior Almassy : The Tadpole and the Flaming Star Nebula In this image taken by +Nicolas Kizilian using a William Optics...
The Tadpole and the Flaming Star Nebula

In this image taken by +Nicolas Kizilian using a William Optics Zenithstar 66 Telescope and a Moravian G2-8300 camera you can see the Tadpole Nebula (IC 410) and the Flaming Star Nebula (IC 405).

IC 410

The Tadpole Nebula (top part of the image) is an emission nebula, located in the constellation of Auriga (https://goo.gl/NT8YKH), about 12,000 light-years away from Earth. The nebula surrounds the open star cluster NGC 1893 (https://goo.gl/wxfy45).

If you look closely you can see two tadpole-shaped structures (hence the name). They are about 10 light-years long and most likely zones of ongoing star formation (https://goo.gl/Mn2Zxf). They are formed by stellar winds (https://goo.gl/Z9Sotn) and radiation from the stars of the open cluster NGC 1893, their tails trail away from the center of the cluster.

IC 405 (SH 2-229, Caldwell 31)

The Flaming Star Nebula (bottom part of the image) is an emission nebula and reflection nebula, also located in the constellation of Auriga, about 1,500 light-years away from Earth. The nebula surrounds the blue O-type main sequence dwarf AE Aurigae (https://goo.gl/NAVJUc).

AE Aurigae is a runaway star (https://goo.gl/54oWQH), it is moving through space at a very high velocity. While it lights up the IC 405 emission nebula it wasn't born in the nebula and is merely "passing through the neighborhood".

More information here:
https://en.wikipedia.org/wiki/IC_405
https://fr.wikipedia.org/wiki/IC_410 (French)
https://apod.nasa.gov/apod/ap151113.html
https://apod.nasa.gov/apod/ap151110.html

The image uses a total exposure time of 12 hours and 30 minutes, it was taken using narrowband filters (https://goo.gl/5yEqCZ), focusing on the emissions of hydrogen, oxygen, and sulfur (HOS image).

More on colors in astrophotography:
https://photographingspace.com/ap-color/

What is a reflection nebula?

A reflection nebula is a cloud of interstellar dust reflecting light from nearby stars. While those stars emit enough energy to make the dust visible they don't emit enough to ionize the gas which would then result in an emission nebula (https://goo.gl/QtI28t). Sometimes you have mixed forms with parts of a nebula being a reflection nebula, others being an emission nebula. More here:
https://en.wikipedia.org/wiki/Reflection_nebula

What is an emission nebula?

An emission nebula is a cloud of ionized gas (often by ultraviolet radiation from nearby stars) emitting light of various colors, in case of HII mostly reddish-pink (when viewed in natural colors). More information here:
https://en.wikipedia.org/wiki/Emission_nebula
https://en.wikipedia.org/wiki/H_II_region

What is an open cluster?

An open cluster is a group of up to a few thousand stars that have their origin in the same stellar nursery and are of roughly the same age. They are bound together by their gravitational forces. More information here:
https://en.wikipedia.org/wiki/Open_cluster

Image credit: IC 410 and IC 405 +Nicolas Kizilian https://goo.gl/XByRWx Used with permission

If you like this image, you can find Nicolas here on G+ (+Nicolas Kizilian), on Twitter (https://twitter.com/NKizilian) and on Facebook (https://www.facebook.com/NicolasKizilian) and see more of his work here on his website:
http://www.astropixels.fr

Thank you for your interest in this Astronomy/Astrophysics collection. Maybe add me on Google+ (+Pierre Markuse) and Twitter (https://twitter.com/Pierre_Markuse) or have a look at the Space/Space Technology collection here: https://goo.gl/5KP0wx

#science #astronomy #astrophotograpy #emissionnebula #reflectionnebula #space #photography #ic410 #ic405 #opencluster #flamingstarnebula #ngc1893
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https://plus.google.com/100267490861780126238 Andrea “ASTRO” Manfredotti : The Atacama Large Millimeter/submillimeter Array (ALMA) in Chile has been adapted to observe the Sun...
The Atacama Large Millimeter/submillimeter Array (ALMA) in Chile has been adapted to observe the Sun. This gives astronomers the ability to witness the G-type main-sequence star in millimetre-wavelength light, giving us more insight into the its physics. 
Sun Can Now Be Observed By ALMA Telescope Array | Video
The Atacama Large Millimeter/submillimeter Array (ALMA) in Chile has been adapted to observe the Sun. This gives astronomers the ability to witness the G-type main-sequence star in millimetre-wavelength light, giving us more insight into the its physics. ALMA Probe Of Hubble Ultra Deep Field Is 'Deeper and Sharper'
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https://plus.google.com/103797026803323116634 kısmet serçe : Stellar Evolution Stellar evolution is the process by which a star undergoes a sequence of radical ...
Stellar Evolution

Stellar evolution is the process by which a star undergoes a sequence of radical changes during its lifetime. Depending on the mass of the star, this lifetime ranges from only a few million years for the most massive to trillions of years for the least massive, which is considerably longer than the age of the universe. All stars are born from collapsing clouds of gas and dust, often called nebulae or molecular clouds. Over the course of millions of years, these protostars settle down into a state of equilibrium, becoming what is known as a main-sequence star.

Nuclear fusion powers a star for most of its life. Initially the energy is generated by the fusion of hydrogen atoms at the core of the main-sequence star. Later, as the preponderance of atoms at the core becomes helium, stars like the Sun begin to fuse hydrogen along a spherical shell surrounding the core. This process causes the star to gradually grow in size, passing through the subgiant stage until it reaches the red giant phase. Stars with at least half the mass of the Sun can also begin to generate energy through the fusion of helium at their core, whereas more massive stars can fuse heavier elements along a series of concentric shells. Once a star like the Sun has exhausted its nuclear fuel, its core collapses into a dense white dwarf and the outer layers are expelled as a planetary nebula. Stars with around ten or more times the mass of the Sun can explode in a supernova as their inert iron cores collapse into an extremely dense neutron star or black hole. Although the universe is not old enough for any of the smallest red dwarfs to have reached the end of their lives, stellar models suggest they will slowly become brighter and hotter before running out of hydrogen fuel and becoming low-mass white dwarfs.

Stellar evolution is not studied by observing the life of a single star, as most stellar changes occur too slowly to be detected, even over many centuries. Instead, astrophysicists come to understand how stars evolve by observing numerous stars at various points in their lifetime, and by simulating stellar structure using computer models.

Explanation from: http://en.wikipedia.org/wiki/Stellar_evolution
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https://plus.google.com/110993708985674782491 Crimson “President of Eumerica” Dalle : This is one of my favorite stories I've written so far. Hope you like it...
This is one of my favorite stories I've written so far. Hope you like it...
Red Velvet Rogue: The first appearance of characters from the Main Sequence Novels set in the Ebbverse
Red Velvet Rogue: (Word count c. 1560) Nov. 21st 2014 By Mickey MacMurphy The Paladin and his horse were both very tired, dusty and worn from the long road behind them, knowing many miles still lay ahead. The soft canter of ...
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https://plus.google.com/114270860415248690597 Helios : On a 12,742 kilometer diameter rock about 149,600,000 kilometers from a yellow main sequence star, members...
On a 12,742 kilometer diameter rock about 149,600,000 kilometers from a yellow main sequence star, members of a bipedal species that had only been around for 0.0043% of the rock's entire 4,600,000,000 year history thought that they were significant.
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https://plus.google.com/105607721191709661081 Mario Valenzuela II (Relique) : Septicycle 2017.02 Creativity. Sustains. Human. Mind. Soul. Septicycle 2017.02.01 Have. Creativity...
Septicycle 2017.02
Creativity. Sustains. Human. Mind. Soul.

Septicycle 2017.02.01
Have. Creativity.

Raw Glyph Data
Save. Mind. Sustain. Soul. Body. Thought. Progress. Creativity. Accept. Human. Harmony. Interrupt. Peace. Enlightenment (Type B). Clear-All. Escape. Answer. Struggle. Lie. Courage. Have. Failure.

Creative expression, in its many forms, creates a conduit into a person's inner most thoughts, their emotions, and soul allowing them to give shape to things that may otherwise be difficult, aid in the creation of new ideas, or allow them to briefly escape our reality.

When creating this week's glyph sequence, I found myself at a conundrum based off the dual glyphs for Creativity and Mind. One of the glyphs for Creativity has a form that derives from the glyph that is commonly used to represent the concept of Mind; the other may also be interpreted as Mind, Thought, and Idea. So the question is which glyph to use for which concept?

Although using the version of Creativity that is derived from the Mind glyph would make sense for the sequence, I decided not to since most agents would be unfamiliar with it. Likewise, I used the glyph commonly associated with the concept of Mind to avoid confusion when an agent tries to the interpret the meaning of the sequence.

What makes this sequence particularly interesting is that depending on how one interprets the glyphs, one can come to an interesting conclusion: The human spirit (soul) and the mind itself requires thoughts, ideas, and creativity to survive. This is interesting because studies have been conducted revolving around possibility that art therapy and creative endeavors could lessen the effects of dementia and Alzheimer’s and could help slow the deteriorative progress of those diseases. It makes me wonder how things would have turned out if my father’s widow gave him a box of paint, crayons, or markers and a sketchbook or easel during the final years of his life rather than having him sit at home and watch tv as he was losing his ability to communicate…

* * * *

Notes: There are twenty-two glyphs on this week’s list rather than ten or the twenty I mentioned previously that I would start using. This was intentional. I will also be using faction glyphs for the daily sequences, but I will try remain faction agnostic for the septicyle’s main sequence. I’m hoping that using the faction glyphs and selecting from an expanded list will give me enough wiggle room so I can create longer and more interesting glyph sequences as the weeks progresses.

Although I am keeping an ink-based analog record of the weekly sequences, for the sake of consistency, when possible, I will post the image I created digitally in photoshop. The “field-like” cloud background will be based on local conditions at the time of my posting, so there is a chance that it would be green, a “teal” color, blue or black/white.

Hopefully, I will find some means to streamline the process of creating these glyph sequences; even if it requires my having to create an online tool or an app…


#ingress #shaperGlyphs #shaperPortents
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https://plus.google.com/115251688654530926288 countessarcadius : Post-main-sequence planetary system evolution http://adsabs.harvard.edu/abs/2016RSOS....350571V
Post-main-sequence planetary system evolution

http://adsabs.harvard.edu/abs/2016RSOS....350571V
Post-main-sequence planetary system evolution
Abstract. The fates of planetary systems provide unassailable insights into their formation and represent rich cross-disciplinary dynamical laboratories. Mounting observations of post-main-sequence planetary systems necessitate a complementary level of theoretical scrutiny. Here, I review the diverse ...
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https://plus.google.com/100494255866518385536 Gabriella “'Kailani Vanessa'” Crofford : Kara Danvers Full name Kara Zor-El Kara Danvers Alias Supergirl Girl of Steel Family Zor-El (biological...
Kara Danvers
Full name Kara Zor-El
Kara Danvers
Alias Supergirl
Girl of Steel
Family Zor-El (biological father)
Alura Zor-El (biological mother)
Jor-El (paternal uncle)
Lara Van-El (paternal aunt)
Astra (maternal aunt)
Non (maternal uncle)
Kal-El (paternal cousin)
Jeremiah Danvers (adoptive father)
Eliza Danvers (adoptive mother)
Alex Danvers (adoptive sister)
Affiliation House of El
CatCo Worldwide Media
D.E.O.
Danvers family
Occupation Reporter
D.E.O. agent
Personal assistant (formerly)
Status Alive
Portrayed by Melissa Benoist
Malina Weissman (young)

Powers & Abilities
Powers
✨Kryptonian Physiology: Like all Kryptonians, Kara possesses the power to absorb the light and radiation of young stars, specifically those in the main sequence yellow spectrum. Her body is constantly absorbing and storing energy from Earth's yellow sun, which in turn grants them incredible powers, such as superhuman strength, senses, impenetrable skin, and even the power to defy gravity.
Yellow Solar Energy Absorption: Like all Kryptoninans in Earth's environment, Kara is able to absorb solar energy from a yellow sun. Her Kryptonian body cells absorb, metabolize and store the energy like a living solar battery, which manifest as her various abilities.
✨Super strength: Chief among Kara's superpowers is her superhuman strength. As all Kryptonians under a yellow sun, Kara has an enormous level of superhuman strength, enough to easily kill a normal human if she were to punch them directly. After embracing her powers and becoming Supergirl, Kara's true potential started to manifest in a slow pace, allowing her to stop a train moving at Mach 1, or even more impressively, lift over a million tons of condensed star material. Additionally, Kara proved strong enough to literately lift Fort Rozz out of the Earth and into Outer Space. While not limitless, the extent of her super-strength is undetermined as of yet; making her among the strongest terrestrial beings in the known universe alongside her cousin and the Martian Manhunter. Despite her strength, Kara still must physically exert herself when fighting other superpowered beings of similar levels of strength and durability, such as other empowered Kryptonians.
✨Super speed: Kara possesses the ability to move at incredible super speeds, far greater than that of any normal human, essentially making her "faster than a speeding bullet"; able to exceed well over the Mach 1 - the speed of sound. Once she started to actually use her powers in a less restrained way, she was easily able to move at supersonic speeds surpassing Mach 3, even to the point where she can almost catch up with a speedster like Barry Allen who could go at mach 13. Additionally, James also implied that Kara is even faster the Clark.
✨Flight: As all Kryptonians under a yellow sun, Kara is able to fly at supersonic-speeds, faster than she can travel by foot, she does this by manipulating her own gravitational field.
Invulnerability: Kara is essentially invulnerable to all Earthly weapons, with bullets simply ricocheting whenever they come in contact with her skin. However, her durability has proved to be somewhat weaker than that of her cousin, Kal-El. This is probably due to the fact that he cousin has spent more time under the Earth's yellow sun than Kara has. She is immune to bullets, lasers, missiles, blades, radiation, cold, and has an extreme heat resistance. she can also survive the pressure of a vacuum.
✨Accelerated healing factor: Kara is able to heal much faster than a normal human. Also, Kara's body processes and burns calories much more faster than any other normal human, meaning she must eat a substantial amount of food depending on how much she exerts herself each day.
✨Super hearing: Kara has super-sensitive ears that can pick up sounds from miles away. She once heard a sound of over 60,000 Hz and can hear the extremely high pitched signal of Jimmy Olsen's watch.
✨Super breath: Kara is able to exhale powerful gusts of air from her mouth. She can also cause the temperature of her breath to drop, therefore able to freeze nearly anything.
X-ray vision: Kara is able to see through all solid objects; except for lead.
✨Heat vision: By concentrating every solar-energy reserve she has in her body, Kara can emit powerful heat lasers from her eyes.
Immunity: Like all Kryptonians, Kara is immune to all forms of diseases and illnesses.
✨Telepathic Immunity: Like all Kryptonians, Kara is immune to all forms of telepathy. However this is different from the Comics as Superman has been mind controlled by several people before.

Abilities
✨Multilingual: Kara is capable of fluently speaking English and her native Kryptonese.
✨Expert Hand-to-Hand Combatant: Since joining the D.E.O., Alex has been teaching Kara to better handle herself in battle against opponents with formidable powers of their own, including how to use their own momentum against them. Ultimately, even with her powers temporarily disabled, Kara has become a highly proficient fighter, able to compete against the more experienced Alex and Astra. As the series went, Kara became even better at this, managing to equal indigo in their fight, also defeating Maxima.

Weaknesses
Kara possesses all the typical weaknesses of a super-powered Kryptonian.
✨Green Kryptonite: Like all Kryptonians, Kara can be weakened by green kryptonite, as it is a radioactive mineral from her home planet Krypton. Green Kryptonite leaves her vulnerable to weapons and anything in general that can kill a normal human. If she is exposed to it for too long, it will kill her.
✨Red Kryptonite: Like all Kryptonians, if Kara is exposed to red kryptonite, it gradually destroys her inhibitions. Gradually she will be left without morality, rationality, or any cares whatsoever. Left with only malice, pride and wrath, Kara will become malevolent and prone to hostility and aggression, making her a danger to everyone around her.
✨Lead: Kara can not see through lead, even with her X-ray vision.
Red sun energy: The energy from a red sun is known to be the Kryptonian's natural sun and therefore, exposure to it will strip them of their powers, rendering them equivalent to an ordinary human on Earth.
✨Extreme energy: Extreme amounts of energy, such as Livewire's electricity, can be enough to kill Kara.
Solar energy depletion: Using her powers to its maximum for an extended period can significantly drain her solar energy to the point where Kara loses all of her powers and is rendered more human like for at least a day. This renders her as weak as a human, allowing Kara to get injured and killed as easy as killing a human.
✨Magic: Like all Kryptonians, Kara can be affected by most forms of magic like any ordinary human. This is because her powers are derived from her natural physiology, not from the supernatural.
Super hearing: Though considered a strength, Kara's hearing does have its disadvantages. Since her hearing is more sensitive than a normal human, higher pitch noises (sonic screams, etc.) can disorient her and cause pain in her ears, leaving her vulnerable in a fight.

Equipment
✨Supergirl suit: Kara wears a suit as her super-heroine alter-ego, Supergirl, to hide her identity from her enemies, when she goes out fighting crime. It was designed by Winn Schott, it is also unknown what materials it is made from.
✨Lead lined glasses: As a teenager Kara was given a pair of lead lined glasses to help her control her visual powers.
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https://plus.google.com/113413756544530838459 Dipendra Verma : Discovery of a hot companion associated with a Blue Straggler in NGC-188 using AstroSat UVIT data: ...
Discovery of a hot companion associated with a Blue Straggler in NGC-188 using AstroSat UVIT data:

(Image in ref: FUV (left) and NUV (right) images of NGC-188 obtained on 18 February 2016. WOCS-5885 is marked as red square)

An Open Star Cluster consists of hundreds to thousands of stars, which are loosely bound. They are formed most likely from a single gas cloud, and are therefore roughly of same age. Open clusters and particularly old open clusters therefore are ideal sites to study the stellar evolution for both single and binary stars. Most stars evolve away from the main sequence once their hydrogen burning phase is over. The turn over point of the Hertzsprung – Russell (HR) diagram of an open cluster is indicative of its age.

Blue Straggler Stars (BSS) are members of old clusters that are brighter and bluer than stars on the upper main sequence. They appear to 'extend' the main sequence in a HR diagram of the cluster and appear as if they are 'younger' stars. They are termed stragglers because they do not move away from the main sequence like the other stars in the same cluster.

NGC-188 is a well-studied old open cluster with an estimated age of 7 Gyr (Billion year, astronomically known as Giga Year- Gyr) and exhibits high metallicity. It is located about 5000 light years away and has about 1050 stars as its members with 20 BSSs confirmed. WOCS-5885, most likely a member of NGC-188 (with a high probability of 53 to 80% quoted in literature), was one of the 3 objects identified with exceptionally blue color. Various classifications a BSS or a sub-dwarf or a binary with a red giant and a pre-white dwarf to name a few were attributed to this object, because its spectrum did not match with any single identification. This could only be resolved if the hot (UV, blue) and the cool (red, IR) part of the spectrum of this object could be fitted together with spectral models of stars. This had been done with observations from space (GALEX, UIT, UVOT, SPITZER, WISE) and several ground based observatories, spanning the IR, optical and UV bands.

The UV band observations from the Ultraviolet Imaging Telescope (UVIT) on ASTROSAT have provided additional points in the Spectral Energy Distribution (SED) thus resulting in a much better spectral fit over the wavelength range of 0.15 µm to 7.8 µm. With this data set, WOCS-5885 has been classified as a binary consisting of a BSS and a hot star which is either a post Asymptotic Giant Branch or Horizontal branch (post-AGB/HB) star.

The UVIT contains two 38-cm telescopes; one for the far-ultraviolet (FUV) region, the other for the near-ultraviolet (NUV) and visible (VIS) regions. These are divided using a dichroic mirror for beam splitting. UVIT is primarily an imaging instrument, simultaneously generating images in the FUV, NUV and VIS channels over a 28 arcmin diameter circular field. Each channel can be divided into smaller pass bands using a selectable set of filters.

UVIT observed NGC-188 both as a first light object and for regular calibration. The observations have been done in both NUV and FUV filters in the wavelength band of 0.3 to 0.15 µm. With these observations, it is found that the SED can only be fit with spectra consisting of 2 stars. The cooler star is found to be a BSS with a temperature of 6,000+150 K, and the temperature of the hotter star is 17,000+500 K. The estimated size and luminosity of the hotter star rule out a white-dwarf or a sub-dwarf classification and hence it is proposed that it could be a post AGB/HB star. If the membership of WOCS-5885 to NGC-188 is confirmed, it could be a rare BSS + post AGB/HB binary, the first of its kind to be identified (for which probability is high) in an open cluster. This system therefore provides a great opportunity to constrain theories of BSS formation via mass transfer.

Thus, observations from the UVIT were used to solve the puzzle of a star WOCS-5885 which appeared as a single star but whose spectra did not match with this identity.

Source:
http://www.isro.gov.in/discovery-of-hot-companion-associated-with-blue-straggler-ngc-188-using-astrosat-uvit-data
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https://plus.google.com/106808239073321070854 Alexander Kruel : Secular Dimming of KIC 8462852 Following its Consumption of a Planet "The Kepler-field star KIC 8462852...
Secular Dimming of KIC 8462852 Following its Consumption of a Planet

"The Kepler-field star KIC 8462852, an otherwise apparently ordinary F3 main-sequence star, showed several highly unusual dimming events of variable depth and duration. Adding to the mystery was the discovery that KIC 8462852 faded by 14% from 1890 to 1989, as well as by another 3% over the 4 year Kepler mission. Following an initial suggestion by Wright & Sigurdsson, we propose that the secular dimming behavior is the result of the inspiral of a planetary body or bodies into KIC 8462852, which took place ~10 to 1e4 years ago (depending on the planet mass). Gravitational energy released as the body inspirals into the outer layers of the star caused a temporary and unobserved brightening, from which the stellar flux is now returning to the quiescent state. The transient dimming events could then be due to obscuration by planetary debris from an earlier partial disruption of the same inspiraling bodies, or due to evaporation and out-gassing from a tidally detached moon system. Alternatively, the dimming events could arise from a large number of bodies comet- or planetesimal-mass bodies placed onto high eccentricity orbits by the same mechanism (e.g. Lidov-Kozai oscillations due to the outer M-dwarf companion) responsible for driving the more massive planets into KIC 8462852. The required high occurrence rate of KIC 8462852-like systems which have undergone recent major planet inspiral event(s) is the greatest challenge to the model, placing large lower limits on the mass of planetary systems surrounding F stars and/or requiring an unlikely probability to catch KIC 8462852 in its current state."

https://arxiv.org/abs/1612.07332
[1612.07332] Secular Dimming of KIC 8462852 Following its Consumption of a Planet
Abstract: The Kepler-field star KIC 8462852, an otherwise apparently ordinary F3 main-sequence star, showed several highly unusual dimming events of variable depth and duration. Adding to the mystery was the discovery that KIC 8462852 faded by 14% from 1890 to 1989, as well as by another 3% ...
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https://plus.google.com/112344184964857951934 brian wang : Tabby star could have brightened after consuming a planet and is now dimming back to normal Arxiv - ...
Tabby star could have brightened after consuming a planet and is now dimming back to normal
Arxiv - Secular Dimming of KIC 8462852 Following its Consumption of a Planet The Kepler-field star KIC 8462852, an otherwise apparently ordinary F3 main-sequence star, showed several highly unusual dimming events of variable depth and duration. Adding to th...
Tabby star could have brightened after consuming a planet and is now dimming back to normal
Arxiv - Secular Dimming of KIC 8462852 Following its Consumption of a Planet The Kepler-field star KIC 8462852, an otherwise apparently ordinary F3 main-sequence star, showed several highly unusual dimming events of variable ...
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