Black Holes

[X-BLACKHOLE]

hello my friends and dear astronomers

we will speak about blackhole and its news in this topic

if you have any question or any idea about the blackhole please share it

:you're kidding, rig

[X-BLACKHOLE]

of course i know that all of you are familier with blackhole's concept and its extraordinary traits
but i have a question of you ?
in your idea, a blackhole can has a distance ?!!
for example you can measuring high and width of a thing !!!
can you do it for a lovely blackhole ?

[planetstruck]

!!!!!!!!!!!Hi there
Dear x-blackhole , I think u should give us some primary information about definition of :yaeh%20am%20not%20dblackholes at first
But it doesn't matter I explain it & give an introduction of blackholes:killzonesmiley:

[planetstruck]

?What is a blackhole
Most people think of a black hole
as a voracious whirlpool in space, sucking down everything around it. But that’s not
really true! A black hole is a place where gravity
has gotten so strong that the escape velocity is faster
than light. But what does that mean, exactly?

A black hole is formed when a star of sufficient mass undergoes gravitational collapse, with most or all of its mass compressed into a ufficiently small area of space, causing infinite spacetime curvature at that point (a "singularity"). Such a massive spacetime curvature allows nothing, not even light, to escape from the "event horizon," or border.
Black holes have never been directly observed, though predictions of their effects have matched observations.

[planetstruck]

How do black holes form



The most common way for a black hole to form is
probably in a supernova, an exploding star. When a star
with about 25 times the mass of the Sun ends its life, it
explodes. The outer part of the star screams outward
at high speed, but the inner part of the star, its core,
collapses down. If there is enough mass, the gravity of
the collapsing core will compress it so much that it can
become a black hole. When it’s all over, the black hole
will have a few times the mass of the Sun. This is called
a “stellar-mass black hole”, what many astronomers
think of as a “regular” black hole.
What happens when you fall into a black hole?
If you fall into a black hole, you’re doomed. Sure, once you fall in you can never get
back out, but it turns out you’ll probably be dead before you get there.
The gravity you feel from an object gets stronger the closer you get. As you approach a
stellar-mass black hole feet-first, the force of gravity on your feet can be thousands of times
stronger than the force on your head! This has the effect of stretching you, pulling you apart like
taffy. Tongue-in-cheek, scientists call this “spaghettification.” By the time you reach the black hole,
you’ll be a thin stream of matter many miles long. It probably won’t hurt though: even falling from
thousands of kilometers away, the entire gory episode will be over in a few milliseconds

[X-BLACKHOLE]

!!!!!!!!!!!Hi there
Dear x-blackhole , I think u should give us some primary information about definition of :yaeh%20am%20not%20dblackholes at first
But it doesn't matter I explain it & give an introduction of blackholes:killzonesmiley:

of course :t5hq2u: it's a resume of blackhole's definition
A black hole is a region of space from which nothing, not even light, can escape. It is the result of the deformation of spacetime caused by a very compact mass. Around a black hole there is an undetectable surface which marks the point of no return. This surface is called an event horizon. It is called "black" because it absorbs all the light that hits it, reflecting nothing, just like a perfect black body in thermodynamics.[1] Quantum mechanics predicts that black holes also emit radiation like a black body with a finite temperature. This temperature decreases with the mass of the black hole, making it difficult to observe this radiation for black holes of stellar mass.

Despite its invisible interior, a black hole can be observed through its interaction with other matter. A black hole can be inferred by tracking the movement of a group of stars that orbit a region in space. Alternatively, when gas falls into a stellar black hole from a companion star, the gas spirals inward, heating to very high temperatures and emitting large amounts of radiation that can be detected from earthbound and Earth-orbiting telescopes.

Astronomers have identified numerous stellar black hole candidates, and have also found evidence of supermassive black holes at the center of galaxies. In 1998, astronomers found compelling evidence that a supermassive black hole of more than 2 million solar masses is located near the Sagittarius A* region in the center of the Milky Way galaxy. Recent results indicate that the supermassive black hole is more than 4 million solar masses.


and if u want to catch more information go to :
http://en.wikipedia.org/wiki/Black_hole

[planetstruck]

U can open this file there are pics on it of blackholes..but u konw i think they aren't real

[stargazer]

I want to take the first picture of a black hole

07 February 2012 by Jon White
__________________________________________________ ___________________________________

Images of a black hole could test general relativity as well as prove they exist, says astronomer Dan Marrone *

[/URL][URL="http://www.newscientist.com/data/images/ns/cms/mg21328500.300/mg21328500.300-1_300.jpg"]http://www.newscientist.com/data/images/ns/cms/mg21328500.300/mg21328500.300-1_300.jpg (http://www.newscientist.com/data/images/ns/cms/mg21328500.300/mg21328500.300-1_300.jpg)

[Marrone and his team are hoping to take the first picture of a black hole in 2015 (Image: Jorge Vieira)]

A black hole (http://www.newscientist.com/article/mg20227091.200-coming-soon-first-pictures-of-a-black-hole.html), by definition, is black. So how are you going to take a picture of one?

If you look right at the black hole it should look quite dark, as very little light escapes. But just around the edge of it you see a bright ring, which is due to the photons that barely missed going into the black hole and skimmed around the edge of it a couple of times. This light is what we think we will be able to detect with the Event Horizon Telescope (http://eventhorizontelescope.org/) (EHT).

The EHT is a "whole Earth telescope". How does it work?

In radio astronomy, to get a higher resolution than you can from a single telescope, you record signals from many telescopes around the world and multiply them together with a special computer. It is as if you have a single telescope almost the size of the Earth.

Which black holes are you targeting?

Sagittarius A* (http://www.newscientist.com/article/mg20727780.900-whats-eating-the-stars-out-of-our-galaxys-heart.html), which is the supermassive black hole at the centre of our galaxy, and the black hole at the centre of M87 (http://www.newscientist.com/article/mg20327223.600-mega-black-hole-twice-as-big-as-we-thought.html), the biggest galaxy in the Virgo cluster of galaxies. With a telescope the size of the Earth and at the frequencies we are observing, we can just make out black holes of this size.

Every image of a black hole so far has been an artist's impression. Will the real thing match expectations?

The question of creating an image from what we measure is a tricky one. We will most likely represent it as a false colour image, using colours to represent how bright the light is. This image will not be as pretty as an artist's impression. The galaxy blurs the light between us and the black hole, so there are a lot of sharp features we can't possibly see. But any image we get shouldn't disappoint - we are looking at something no one has ever seen before.

What about capturing a moving image - "black hole, the movie" as it were?

We can, if there is something orbiting the black hole, as we expect there will be. If there is gas orbiting before it falls into the black hole, this takes between 4 and 27 minutes, depending on the spin of the black hole. If we look for several days and see changes in the structure, we can represent that as a movie as well.

What are you hoping to learn from this image?

Just being able to take a picture of a black hole, and show this shadow that we expect to be there because the light is not escaping, will be important. Beyond that we have a lot to learn about the structure of our galaxy's black hole, and what happens to a black hole when it is being starved of material, as Sagittarius A* appears to be.

We also expect to be able to test general relativity (http://www.newscientist.com/article/mg20727672.100-general-relativity-black-holes.html), which tells us that the ring of light around the edge of the black hole needs to be perfectly circular. If general relativity is breaking in this very strong field regime, where gravity is at the limits of its power, then this ring of light won't be perfectly circular.

*(Profile: Dan Marrone (https://www.as.arizona.edu/people/faculty/marrone.html) is an astronomer at the University of Arizona Steward Observatory. He is part of the Event Horizon Telescope programme, inaugurated last month, which aims to take the first picture of a black hole in 2015)

From: NewScientist

[رخساره روشنی]

I think one of the best objects in the universe are black holes In the past I was afraid of the black hole but when I realized that After the death of stars, black hole is create I've changed my opinion because it's very exciting and I think imaginable
this is link of short clip about black hole:
http://www.faupload.com/upload/90/Bahman/Black-hole-destroying-a-star.flv

[stargazer]

And there is another text by Clay Dillow which posted on 02.16.2012 , about :

"How to take a picture of a black hole"

[/URL]http://www.popsci.com/files/imagecache/article_image_large/articles/ALMA_Prototype-Antennas_at_the_ALMA_Test_Facility.jpeg (http://www.popsci.com/files/imagecache/article_image_large/articles/ALMA_Prototype-Antennas_at_the_ALMA_Test_Facility.jpeg)
ALMA Prototype Radio Antennas ALMA (ESO/NAOJ/NRAO)

You can check it here too: [URL]http://www.popsci.com/technology/article/2012-02/how-take-picture-black-hole

[Saeed Jafari]

NASA, UC Berkeley team to research black holes with space telescope

By Mateo Garcia (http://www.dailycal.org/author/mgarcia/) | Staff
Last Updated 20 hours Ago

A new NASA telescope, headed by the UC Berkeley Space Sciences Laboratory, will reach orbit on Wednesday and eventually help researchers study the growth of galaxies.

The Nuclear Spectroscopic Telescopic Array, referred to as NuSTAR, will seek out black holes in other Milky Way Galaxy as well as our own by picking up on high energy X-rays emitted from the edge of these dark masses of gravity.

“NuSTAR will help us to understand how galaxies and black holes grow and influence each other as the universe evolves,” said Fiona Harrison, a professor of physics and astronomy at the California Institute of Technology and leader of the mission. “We know black holes influence galaxy growth, and NuSTAR will make great strides in our understanding of this process.”

Approximately 15 years in the making, NuSTAR is not the first attempt at an instrument designed to detect X-rays, although it has the potential to be the most successful. William Craig, instrument manager and instrument systems engineer for NuSTAR at the Space Sciences Lab at UC Berkeley, has high hopes for the telescope, which was launched last Wednesday.
“The NuSTAR telescope is an exciting technological breakthrough,” Craig said. “The optics modules, (which) act as the lens for the telescope, are the first to allow true focusing in the high energy X-ray range and allow us to look more than a hundred times deeper than previous attempts to explore this region of the electromagnetic spectrum.”

According to a NASA press release, the observatory will be able to see through gas and dust, unlike most telescopes, and reveal black holes lurking in the Milky Way, as well as those hidden deep inside the cores of surrounding galaxies.

The telescope features 133 individual tilted mirrors opposite from digital detectors similar to those used in cell phone cameras that will convert the X-rays to images. The extendable mast in between these components is one of the “very impressive engineering accomplishments that allowed (the NuSTAR team) to put a 33-foot focal length telescope on the smaller, less expensive rocket that is available for this smaller class of NASA science missions,” according to Craig.

About three weeks after NuSTAR is in orbit, the observatory will begin its work of locating black holes and studying the remnants of exploded stars, in addition to looking at our sun’s atmosphere for clues as to how it is heated.

“NuSTAR will see black holes as points of X-ray light both in our own galaxy, and at the hearts of other galaxies,” Harrison said. “If NuSTAR sees a point of high energy X-ray light in the center of a galaxy it is certainly a massive black hole — millions to billions of times the mass of our sun.”

Although the majority of its funding is provided by NASA, the development of NuSTAR has been the result of a large effort made by many different entities. The NuSTAR mission has involved international partners including the Italian Space Agency, which is providing the ground station for the mission, the Technical University of Denmark, who contributed to the X-ray optics and international members of the science team who are funded independently by other governments.

As of now, no problems have arisen with the mission, Harrison said.

“After a successful launch into a very good orbit, we have been commissioning the spacecraft and are proceeding as planned. The instrument commissioning process has begun and everything is working nominally,” Craig said. “The team is very much looking forward to getting the telescope mast extended on Thursday of this week and moving on to our first target — a black hole in our galaxy known as Cygnus X-1.”


http://www.dailycal.org

[gandom]

As you are likely aware, there are numerous ways in which the Universe could kill us all, destroying the Earth and whatever signs of human life, or life in general, existed on our planet. Gamma Ray Bursts, Coronal Mass Ejections, or just the odd asteroid or comet slamming into the Earth would easily take out most of the life on our planet. But, what about black holes? Do we have to worry about them, too


http://up.avastarco.com/images/02otn7vhm9jx93qq64o3.jpg (http://up.avastarco.com/images/02otn7vhm9jx93qq64o3.jpg)


Could a black hole wipe out all life on Earth, sucking us all into oblivion? It’s possible, but not very likely. And by not very likely, it’s calculated that the odds of being killed by a black hole are about First, a black hole has to get to the Earth.There are two ways of this happening. The first is that we create one ourselves, the second that a black hole wandering the galaxy happens upon our little Solar System, and meanders in towards the Sun. We’ll start with the first scenario: creating our own destruction.




.................................................. ....
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if members give me a hand,we will continue this topic to get the best target!
-you will need fundametal information that you can get them in this topic (http://forum.avastarco.com/forum/showthread.php?279-Black-Holes)

about the pic:Magnetic field around a black hole. Image credit: NASA

Read more: http://www.universetoday.com/38434/black-hole-on-earth/#ixzz20mbHKgug

[Saeed Jafari]

New Type of Black Hole Found—Relic of Early Universe


Middleweight black hole may explain how giant cousins formed


http://images.nationalgeographic.com/wpf/media-live/photos/000/560/overrides/new-type-middleweight-black-hole-discovered_56025_600x450.jpg (http://images.nationalgeographic.com/wpf/media-live/photos/000/560/overrides/new-type-middleweight-black-hole-discovered_56025_600x450.jpg)
The newly identified black hole, circled, sits within a star cluster

Image courtesy S. Farrell, U. Sydney/U. Leicester/ESA/NASA


Andrew Fazekas
for National Geographic News (http://news.nationalgeographic.com)
Published July 5, 2012
There's a strange new brute on the celestial block—the middleweight black hole (http://science.nationalgeographic.com/science/space/universe/black-holes-article/), a new study says.
After nearly three years of spying a superbright object nearly 300 million light-years away, astronomers with NASA's Chandra X-ray Observatory (http://www.nasa.gov/mission_pages/chandra/main/index.html) and SWIFT telescope (http://www.nasa.gov/mission_pages/swift/main/index.html) recently announced the discovery of HLX-1, the first representative of a new type of black hole. (See black hole pictures (http://science.nationalgeographic.com/science/photos/black-holes-gallery/).)
(Related: "New Class of Black Hole Found? [2009]." (http://news.nationalgeographic.com/news/2009/07/090701-new-black-hole.html))
Until recently, black holes were thought to come in only two sizes: Small stellar varieties that are several times heavier than our sun, and supermassive black holes that pack the gravitational punch of many million suns—large enough to swallow our entire solar system.
Notorious for ripping apart and swallowing stars (http://science.nationalgeographic.com/science/space/universe/stars-article/), extra-large black holes live exclusively in the hearts of most galaxies, including our own Milky Way.
The new middleweight black hole is between these two types—equal to the matter of about 90,000 suns (http://science.nationalgeographic.com/science/space/solar-system/sun-article/).
New Black Hole Relics of the Early Universe?
An international team, who discovered HLX-1 "almost by accident" in 2009, noticed the object was pumping out copious amounts of x-rays and radio flares—not from within the core of its host spiral galaxy, but some 12,000 light years beyond
"Our observations from 2009 and 2010 showed that HLX-1 behaves similarly to the stellar [low] mass black holes, so we worked out when we should be expecting to see radio flares from HLX-1, and when we made more observations in August and September 2011, we did," said study leader Natalie Webb, of the Centre d'Etude Spatiale des Rayonnements (http://www.cesr.fr/) in France
The origin of these intermediate black holes may lie in centers of globular clusters, where hundreds of thousands of stars are densely packed together by gravity
Alternatively, the middleweights may be true ancient relics of the universe (http://science.nationalgeographic.com/science/space/universe/), formed by the very earliest stars, said Webb, whose study appears tomorrow in the journal Science (http://www.sciencemag.org/)
(Read more about the origins of the universe (http://science.nationalgeographic.com/science/space/universe/origins-universe-article/))
"At the dawn of the universe, very massive stars may have existed—maybe as much as ten thousand times the mass of our sun—and these stars would have 
a very short lifetime and end their lives as intermediate mass black 
holes," Webb said
Middleweights May Explain Black Hole Giants
The very existence of middleweight black holes may also be key in solving how their supermassive cousins formed. (Read about NASA's new "black hole hunter." (http://news.nationalgeographic.com/news/2012/06/120612-nasa-black-holes-supernovas-nustar-launch-space-science/))
For instance, Webb suspects the middleweights may in fact be the supermassive black holes' progenitors
These giants may either form when a single intermediate black hole gobbles enough matter to grow into a supermassive black hole with at least a million solar masses
Or, a number of intermediate black holes "merged in the early universe to form the supermassive black holes we see today," Webb said
Either way, without further surveys, it's impossible to tell how common middleweight black holes are across the universe
"It's difficult to assess observationally, as [HLX-1] is the only good candidate," Webb said.
"But some people think that there may be hundreds in each and every galaxy"


http://http://news.nationalgeographic.com/news/2012/07/120705-new-black-hole-middleweight-space-science-universe/

[Saeed Jafari]

Bonanza of Black Holes, Hot DOGs: NASA's WISE Survey Uncovers Millions of Black Holes


A Sky Chock-Full of Black Holes: With its all-sky infrared survey, NASA's Wide-field Infrared Survey Explorer, or WISE, has identified millions of quasar candidates. (Credit: NASA/JPL-Caltech/UCLA)


http://images.sciencedaily.com/2012/08/120829144518-large.jpg?1346266005 (http://images.sciencedaily.com/2012/08/120829144518-large.jpg?1346266005)



ScienceDaily (Aug. 29, 2012) — NASA's Wide-field Infrared Survey Explorer (WISE) mission has led to a bonanza of newfound supermassive black holes and extreme galaxies called hot DOGs, or dust-obscured galaxies.
Images from the telescope have revealed millions of dusty black hole candidates across the universe and about 1,000 even dustier objects thought to be among the brightest galaxies ever found. These powerful galaxies, which burn brightly with infrared light, are nicknamed hot DOGs.
"WISE has exposed a menagerie of hidden objects," said Hashima Hasan, WISE program scientist at NASA Headquarters in Washington. "We've found an asteroid dancing ahead of Earth in its orbit, the coldest star-like orbs known and now, supermassive black holes and galaxies hiding behind cloaks of dust."




Read more


http://www.sciencedaily.com/releases/2012/08/120829144518.htm

[Saeed Jafari]

Monster Galaxy May Have Been Stirred Up by Black-Hole Mischief


ScienceDaily (Oct. 25, 2012) — Astronomers using NASA's Hubble Space Telescope have obtained a remarkable new view of a whopper of an elliptical galaxy that may have been puffed up by the actions of one or more black holes in its core


Spanning a little more than one million light-years, the galaxy is about 10 times the diameter of our Milky Way galaxy. The bloated galaxy is a member of an unusual class of galaxies with a diffuse core filled with a fog of starlight where there would normally be a concentrated peak of light around a central black hole. Viewing the core is like seeing a city with no downtown, just houses sprinkled across a vast landscape



Astronomers used Hubble's Advanced Camera for Surveys and Wide Field Camera 3 to measure the amount of starlight across the galaxy, dubbed A2261-BCG. The Hubble observations revealed that the galaxy's puffy core, measuring about 10,000 light-years, is the largest yet seen



http://images.sciencedaily.com/2012/10/121025130724-large.jpg (http://images.sciencedaily.com/2012/10/121025130724-large.jpg)


The giant elliptical galaxy in the center of this image, taken by NASA's Hubble Space Telescope, is the most massive and brightest member of the galaxy cluster Abell 2261

[gandom]

I'm so sorry about the long delay:sad:!

so let start with the whole general information about black holes. in the beginning of this topic i link you to the black holes topic to stop repetition:wink:
and now i want to introduce a kind of black hole that we can make it on earth. but don't worry it's not strong enough to swallow our earth into a dark and mysterious place:wink:

Micro black hole

http://up.avastarco.com/images/v2ggwebhifurjvanyaus.jpeg (http://up.avastarco.com/)

micro black holes are also called quantum mechanical black holes or mini black holes. we call them quantum mechanic black holes cause the quantum mechanic plays an important role in their behavior. they can be form even by little range of energy such as LHC (http://wiki.avastarco.com/index.php?title=%D8%B4%D8%AA%D8%A7%D8%A8_%D8%AF%D9 %87%D9%86%D8%AF%D9%87_%D8%A8%D8%B2%D8%B1%DA%AF_%D9 %87%D8%A7%D8%AF%D8%B1%D9%88%D9%86) produce!
imagine that on the earth and in a collider we can build a black hole!
but the story ends as soon as possible...cause how small a black hole is....the evaporation of it would happens immediately.
the evaporation of a black hole....you read correctly... a black hole wont be last forever without feeding and binding energy.
so now before we lose our black hole we need to know how does this micro black hole forms


sources: wikiastro,en.wikipedia

[Saeed Jafari]

NASA's NuSTAR Helps Solve Riddle of Black Hole Spin


[/URL]http://www.nasa.gov/images/content/730096main_pia16695-673.jpg (http://www.nasa.gov/images/content/730096main_pia16695-673.jpg)

This artist's concept illustrates a supermassive black hole with millions to billions times the mass of our sun. Supermassive black holes are enormously dense objects buried at the hearts of galaxies.


PASADENA, Calif. -- Two X-ray space observatories, NASA's Nuclear Spectroscopic Telescope Array (NuSTAR) and the European Space Agency's XMM-Newton, have teamed up to measure definitively, for the first time, the spin rate of a black hole with a mass 2 million times that of our sun.
The supermassive black hole lies at the dust- and gas-filled heart of a galaxy called NGC 1365, and it is spinning almost as fast as Einstein's theory of gravity will allow. The findings, which appear in a new study in the journal Nature, resolve a long-standing debate about similar measurements in other black holes and will lead to a better understanding of how black holes and galaxies evolve.
"This is hugely important to the field of black hole science," said Lou Kaluzienski, a NuSTAR program scientist at NASA Headquarters in Washington.
The observations also are a powerful test of Einstein's theory of general relativity, which says gravity can bend space-time, the fabric that shapes our universe, and the light that travels through it.


http://www.nasa.gov/images/content/730086main_pia16697c-43_226-170.jpg (http://www.nasa.gov/images/content/730086main_pia16697c-43_226-170.jpg)


Scientists measure the spin rates of supermassive black holes by spreading the X-ray light into different colors



[URL]http://www.nasa.gov/mission_pages/nustar/news/nustar20130227.html