تیتان قمر زحل مدت هاست که به عنوان قمری که بسیار شبیه گذشته زمین است مطرح شده و تحقیق های اخیر وجود اسید های آمینه که به عنوان بلوک های اولیه ی حیات به شمار می روند را در جو تیره این قمر تایید کرده اند.
برای مطالعه ادامه مطلب بر روی لینک ادامه مطلب کلیک نمایید.
پدیده ی لنز گرانشی که یکی از دستاورد های نظریه نسبیت عام انیشتین محسوب می شود بارها و بارها با خلق تصاویر زیبای حلقه ها و کمان ها مشاهده شده.
در این پدیده ی زیبا، نور منتشر شده از جسم پر جرم بسیار دور - مثلا کهکشان - زمانی که از نزدیکی جسم پر جرمی دیگر که در مسیر دید ناظر قرار دارد ، عبور می کند ، خم شده و تصاویری زیبا ایجاد می کند.
این بار برای اولین بار یک کوازار باعث خلق یکی از این تصاویر شده است !
در ادامه خبر مربوط به این موضوع را برای علاقه مندان قرار داده ام . . .
برای مطالعه ادامه مطلب بر روی لینک ادامه مطلب کلیک نمایید.
بد نیست بدانید که ساکنان ایستگاه فضایی در هر روز 16 بار افتخار دیدن طلوع خورشید را می یابند.
برای مطالعه ادامه مطلب بر روی لینک ادامه مطلب کلیک نمایید.
Scientists have used NASA's Chandra X-ray Observatory and ESA's XMM-Newton to detect a vast reservoir of gas lying along a wall-shaped structure of galaxies about 400 million light years from Earth. In this artist's impression, a close-up view of the so-called Sculptor Wall is depicted. Spiral and elliptical galaxies are shown in the wall along with the newly detected intergalactic gas, part of the so-called Warm Hot Intergalactic Medium (WHIM), shown in blue. This discovery is the strongest evidence yet that the "missing matter" in the nearby Universe is located in an enormous web of hot, diffuse gas.
برای مطالعه ادامه مطلب بر روی لینک ادامه مطلب کلیک نمایید.
In a manner somewhat like the formation of an alliance to defeat Darth Vader's Death Star, more than a decade ago astronomers formed the Whole Earth Blazar Telescope consortium to understand Nature's Death Ray Gun (a.k.a. blazars). And contrary to its at-death's-door sounding name, the GASP has proved crucial to unraveling the secrets of how Nature's "LHC" works.
برای مطالعه ادامه مطلب بر روی لینک ادامه مطلب کلیک نمایید.
این بار بخش انتقال به سرخ نسبیت عام مورد آزمایش قرار گرفت.
با چه دقتی ؟
با دقتی بهتر از 1 قسمت در 100 میلیون !
برای مطالعه ادامه مطلب بر روی لینک ادامه مطلب کلیک نمایید.
Another technique has been added to the exo-planet hunters' toolkit, and it doesn't require huge ground-based telescopes or space-based observatories. A group of astronomers developed the new technique by using a relatively small Earth-based infrared telescope to identify an organic molecule in the atmosphere of a Jupiter-sized planet nearly 63 light-years away. This new ground-based technique will enable the study of atmospheres of planets outside our Solar System, accelerating our search for Earth-like planets with life-related molecules.
برای مطالعه ادامه مطلب بر روی لینک ادامه مطلب کلیک نمایید.
اطلاعات رصدی بدست آمده از 9 تپنده ( پالسار ) ، پیشنهاد می کند که این چرخنده های سریع [و این] ستاره های نوترونی معادل الکترومغناطیسی شکست دیوار صوتی و سرعت مافوق صوت را از خود انتشار می کنند و مدلی که برای فهم این پدیده استفاده می شود، نشان می دهد که منبع این پرتوها می تواند با سرعتی فراتر از سرعت نور حرکت کند !
محققان بیان می دارند که جریان های قطبیده در این پرتو ها با مکانیزمی شبیه سینکروترون به اطراف پخش می شوند و منابع این جریان ها می تواند با سرعتی بیش از 6 برابر سرعت نور حرکت کند ! یا معادل 1.8 میلیون کیلومتر برثانیه !
این پدیده علمی تخیلی نیست ضمن این که خلاف قوانین فیزیکی هم نمی باشد و نسبیت انیشتین را نقض نمی کند!
تنها کافی است ادامه این متن را بخوانید تا متوجه موضوع شوید .
برای مطالعه ادامه مطلب بر روی لینک ادامه مطلب کلیک نمایید.
برای مطالعه ادامه مطلب بر روی لینک ادامه مطلب کلیک نمایید.
Astronomers say it’s a "neck-and-neck race" as to whether the first potentially habitable planets will be detected from the ground or from space, and today an international team of planet hunters announced they have discovered as many as six low-mass planets around two nearby Sun-like stars, using two ground-based observatories. This haul of planets includes two "super-Earths" with masses 5 and 7.5 times the mass of Earth .
برای مطالعه ادامه مطلب بر روی لینک ادامه مطلب کلیک نمایید.
As galaxies evolve, many lose their gas. But how they do this is a point of contention. One possibility is that it is used to form stars when the galaxies undergo intense periods of star formation known as starburst. Another is that when large galaxies collide, the stars pass through one another but the gas gets left behind. It's also possible that the gas is pulled out in close passes to other galaxies through tidal forces. Yet another possibility involves a wind blowing the gas out as galaxies plunge through the thin intergalactic medium in clusters through a process known as ram pressure.
برای مطالعه ادامه مطلب بر روی لینک ادامه مطلب کلیک نمایید.
خورشید از دو سال قبل تاکنون بدون لکه و یا هر فعالیت چشمگیر خاصی بوده است و تازه ترین تصاویری که کاوشگر اروپایی "سوهو" 7 آگوست از خورشید به زمین ارسال کرد نشان می دهد که ستاره منظومه شمسی همچنان به خواب خود ادامه می دهد.
برای مطالعه ادامه مطلب بر روی لینک ادامه مطلب کلیک نمایید.
In a 2006 book that garnered much press for its silly attacks on string theory, author and physicist Lee Smolin provides a list of “The Five Great Problems in Theoretical Physics.” There are many offensive things about this list, starting with the use of the definite article in the title, which implies that people not working on these problems (the majority of theoretical physicists) are working on less-than-great problems. But to me the most offensive thing is that only one of the five problems, I believe, could eventually be resolved by experiment.
برای مطالعه ادامه مطلب بر روی لینک ادامه مطلب کلیک نمایید.
When it comes to universes, perhaps one is enough after all.
Many theories in physics and cosmology require the existence of alternate, or parallel, universes. But Dr. Lee Smolin of the Perimeter Institute for Theoretical Physics in Waterloo, Canada, explains the flaws of theories that suggest our universe is just one of many, and which also perpetuate the notion that time does not exist. Smolin, author of the bestselling science book ‘The Trouble with Physics’ and a founding member of the Perimeter Institute, explains his views in the June issue of Physics World.
برای مطالعه ادامه مطلب بر روی لینک ادامه مطلب کلیک نمایید.
380,000 years after the Big Bang, the Universe cooled from being a hot soup of plasma, to a temperature where protons and electrons could combine to form atoms. This calm period of neutral hydrogen in universal history didn’t last for long however. The neutral hydrogen atoms were ripped apart once more, by a mechanism that would go on to reionize the entire Universe, a process that eventually ended a billion years after the Big Bang.
A billion years after the big bang, hydrogen atoms were mysteriously torn apart into a soup of ions.
برای مطالعه ادامه مطلب بر روی لینک ادامه مطلب کلیک نمایید.
گروهی از محققان گرانش با استفاده از یک پیکر بندی که شامل 16 پلی استیشن ۳ بود نوعی ابر کامپیوتر ساختند تا آن ها را در تخمین امواج گرانشی ایجاد شده توسط دو سیاه چاله ادغام شدهیاری نماید .
برای مطالعه ادامه مطلب بر روی لینک ادامه مطلب کلیک نمایید.
2008 has been an astounding year of scientific discovery. To celebrate this fact, Time Magazine has listed the "Top 10 Scientific Discoveries" where space exploration and physics dominate. Other disciplines are also listed; including zoology, microbiology, technology and biochemistry, but the number 1 slot goes to the most ambitious physics experiment of our time. Can you guess what it is? Also, of all our endeavours in space, can you pick out three that Time Magazine has singled out as being the most important?
برای مطالعه ادامه مطلب بر روی لینک ادامه مطلب کلیک نمایید.
سازمان ناسا گوش دادن به سیگنال های ارسالی توسط این مریخ نشین را متوقف کرده است. . .
برای مطالعه ادامه مطلب بر روی لینک ادامه مطلب کلیک نمایید.
NASA's Cassini mission has detected liquid hydrocarbons on Saturn's moon Titan, in a large, glassy lake near the moon's south pole. Before the Cassini mission began, scientists thought Titan would have global oceans of methane, ethane and other light hydrocarbons. But after more than 40 close flybys of Titan by Cassini, data showed no global oceans exist.
برای مطالعه ادامه مطلب بر روی لینک ادامه مطلب کلیک نمایید.
Einstein's theory of General Relativity has been around for 93 years, and it just keeps hanging in there. With advances in technology has come the ability to put the theory under some scrutiny. Recently, taking advantage of a unique cosmic coincidence, as well as a pretty darn good telescope, astronomers looked at the strong gravity from a pair of superdense neutron stars and measured an effect predicted by General Relativity. The theory came through with flying colors.
برای مشاهده ی ادامه مطلب بر روی لینک ادامه مطلب کلیک نمایید.
So neutron stars may not be the densest exotic objects in the cosmos after all. Recent observations of ultra-luminous supernovae suggest that these explosions may create an even more exotic remnant. Neutron stars can form after a star ends its life; measuring only 16 km across, these small but massive objects (one and a half times the mass of the Sun) may become too big for the structure of neutrons to hold it together. What happens if the structures of the neutrons inside a neutron star collapse? Quark stars (a.k.a. "Strange" stars) may be the result, smaller and denser than neutron stars, possibly explaining some abnormally bright supernovae observed recently…
جهت مشاهده ادامه مطلب بر روی لینک ادامه مطلب کلیک نمایید .
What happened before the Big Bang? The conventional answer to that question is usually, "There is no such thing as 'before the Big Bang.'" That's the event that started it all. But the right answer, says physicist Sean Carroll, is, "We just don't know." Carroll, as well as many other physicists and cosmologists have begun to consider the possibility of time before the Big Bang, as well as alternative theories of how our universe came to be. Carroll discussed this type of "speculative research" during a talk at the American Astronomical Society Meeting last week in St. Louis, Missouri.
جهت مشاهده ادامه مطلب بر روی لینک ادامه مطلب کلیک نمایید .
Core may produce one of the lightweight particles called axions
The identity of the mysterious dark matter thought to pervade the universe has eluded astrophysicists for decades. Now, for the first time a team hopes to look inside the sun for one of the prime candidates.
The invisible stuff called dark matter is thought to make up as much as 90 percent of the universe's matter. To date, astrophysicists have only inferred the existence of some mysterious substance by identifying its gravitational effects on visible matter such as stars and galaxies. (For instance, dark matter makes galaxies spin faster than otherwise expected.)
جهت مشاهده ادامه مطلب بر روی لینک ادامه مطلب کلیک نمایید .
The search is on to detect the first evidence of gravitational waves travelling around the cosmos. How can we do this? The Laser Interferometer Gravitational-Wave Observatory (LIGO) uses a system of laser beams fired over a distance of 4 km (2.5 miles) and reflected back and forth by a system of mirrors. Should a gravitational wave pass through the volume of space-time surrounding the Earth, in theory the laser beam will detect a small change as the passing wave slightly alters the distance between mirrors. It is worth noting that this slight change will be small; so small in fact that LIGO has been designed to detect a distance fluctuation of less than one-thousandth of the width of a proton. This is impressive, but it could be better. Now scientists think they have found a way of increasing the sensitivity of LIGO; use the strange quantum properties of the photon to "squeeze" the laser beam so an increase in sensitivity can be achieved…
جهت مشاهده ادامه مطلب بر روی لینک ادامه مطلب کلیک نمایید .
سلام و درود فراوان بر بازدید کنندگان محترم .