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Σάββατο 31 Οκτωβρίου 2015

Αρχέγονο φως ίσως ανήκει σε άλλο Σύμπαν!

Αρχέγονο φως ίσως ανήκει σε άλλο Σύμπαν!

Ερευνητές μελετούν μυστηριώδη λαμπερά σημεία που προέρχονται από τη γέννηση του Κόσμου
Αρχέγονο φως ίσως ανήκει σε άλλο Σύμπαν!
H μυστηριώδης λάμψη που εντόπισαν οι επιστήμονες ίσως αποκαλύπτει την ύπαρξη ενός Πολυσύμπαντος


 
 
Ομάδα αστρονόμων με επικεφαλής τον Ράνγκα-Ραμ Χάρι, καθηγητή του California Institute of Technology εντόπισαν άγνωστα μέχρι σήμερα λαμπερά σημεία στον χάρτη της ακτινοβολίας μικροκυμάτων, η οποία διαπερνά μέχρι σήμερα το Σύμπαν ως «απόηχος» της αρχικής «Μεγάλης Έκρηξης» από την οποία σύμφωνα με την κρατούσα θεωρία γεννήθηκε το Σύμπαν.

O κομήτης του Rosetta έχει οξυγόνο!

O κομήτης του Rosetta έχει οξυγόνο!

Η ανακάλυψη αλλάζει τα δεδομένα για τον σχηματισμό του ηλιακού μας συστήματος
O κομήτης του Rosetta έχει οξυγόνο!
Ο κομήτης 67Ρ διαθέτει οξυγόνο ανακάλυψη που υποχρεώνει τους επιστήμονες να επανεξετάσουν όσα γνωρίζουμε για τον σχηματισμό του ηλιακού μας συστήματος. Credit: (ESA/NAVCAM)


 
Το ευρωπαϊκό διαστημικό σκάφος Rosetta ανακάλυψε οξυγόνο σε αφθονία στην ατμόσφαιρα του κομήτη 67P, κάτι που κατέπληξε τους επιστήμονες οι οποίοι εκτιμούν ότι ίσως θα πρέπει να επανεξεταστούν οι θεωρίες τους για τον σχηματισμό του ηλιακού μας συστήματος.

Μεγάλος αστεροειδής στην γειτονιά μας

Μεγάλος αστεροειδής στην γειτονιά μας

Θα περάσει κοντά από τη Γη στης 31 Οκτωβρίου αλλά δεν μας απειλεί
Μεγάλος αστεροειδής στην γειτονιά μας
Καλλιτεχνική απεικόνιση του αστεροειδή 2015 ΤΒ145 που θα περάσει κοντά από τη Γη


 
Ενας μεγάλος αστεροειδής με διάμετρο περίπου 400 μέτρων θα περάσει αύριο σχετικά κοντά από τον πλανήτη μας. Το πέρασμα, με ταχύτητα 35 χλμ ανά δευτερόλεπτο, θα γίνει αύριο το βράδυ στις 7 μ.μ. ώρα Ελλάδας σε απόσταση 480.000 χιλιομέτρων, λίγο μεγαλύτερη από την απόσταση Γης-Σελήνης.

Ιοί που σκοτώνουν τον καρκίνο φιλοδοξούν να γίνουν viral

Ιοί που σκοτώνουν τον καρκίνο φιλοδοξούν να γίνουν viral

Η αμερικανική Υπηρεσία Τροφίμων και Φαρμάκων ενέκρινε έναν γενετικά τροποποιημένο ιό για την αντιμετώπιση του καρκίνου
Ιοί που σκοτώνουν τον καρκίνο φιλοδοξούν να γίνουν viral
O ογκολυτικός ιός προσκαλεί Τ-κύτταρα του ανοσοποιητικού συστήματος (πορτοκαλί) να επιτεθούν στους όγκους (πράσινο). Εικόνα αρχείου: Steve Gschmeissner/Science Source


Ουάσινγκτον 
Για πρώτη φορά στον Δυτικό κόσμο, η αμερικανική FDA (Υπηρεσία Τροφίμων και Φαρμάκων) ενέκρινε έναν γενετικά τροποποιημένο ιό για την αντιμετώπιση του καρκίνου: έναν ιό που προσκαλεί το ανοσοποιητικό σύστημα να επιτεθεί στους όγκους.

Υπερυπολογιστής προσομοιώνει την εξέλιξη του Σύμπαντος

Υπερυπολογιστής προσομοιώνει την εξέλιξη του Σύμπαντος

Παρουσιάζει την πορεία του από την βρεφική του ηλικία μέχρι και σήμερα και συνοδεύεται από έναν ωκεανό δεδομένων 2,5 petabyte
Υπερυπολογιστής προσομοιώνει την εξέλιξη του Σύμπαντος
H ύλη του Σύμπαντος ήταν αρχικά σχετικά ομοιογενής (αριστερά), σταδιακά όμως συσσωματώθηκε και σχημάτισε τον κοσμικό ιστό (δεξιά)


Σικάγο, Ίλινοϊ 
Σε μια από τις μεγαλύτερες κοσμολογικές προσομοιώσεις που έχουν παρουσιαστεί ως σήμερα, υπερυπολογιστής του αμερικανικού υπουργείου Ενέργειας μοντελοποιεί την εξέλιξη του Σύμπαντος από τη βρεφική του ηλικία μέχρι σήμερα. Το αποτέλεσμα; Ένας ωκεανός δεδομένων που φτάνει τα 2,5 petabyte, ή 2,5 εκατομμύρια gigabyte.

Nobel-winning drug 'tackles malaria'

Nobel-winning drug 'tackles malaria'

  • 27 October 2015
  • From the section Health
 Nurses diagnosing malaria fevers in children in Burkina
Image copyright Brian Foy
Image caption Nurses diagnosing malaria fevers in children in Burkina Faso
A parasitic-worm-killing drug, whose discovery won the Nobel prize, may also cut cases of malaria, say researchers.
Early data coming out of trials of ivermectin in Burkina Faso suggest it leads to 16% fewer cases of childhood malaria.
Scientists at the American Society of Tropical Medicine and Hygiene's conference, said the drug was toxic to blood-drinking mosquitoes.

Processed meats do cause cancer - WHO

Processed meats do cause cancer - WHO

  • 26 October 2015
  • From the section Health
  • 750 comments

Bacon sarnie Image copyright Thinkstock

Processed meats - such as bacon, sausages and ham - do cause cancer, according to the World Health Organization (WHO).
Its report said 50g of processed meat a day - less than two slices of bacon - increased the chance of developing colorectal cancer by 18%.
Meanwhile, it said red meats were "probably carcinogenic" but there was limited evidence.
The WHO did stress that meat also had health benefits.

TB 'joins HIV as most deadly infection'

  • 28 October 2015
  • From the section Health
 Lungs with tuberculosis
Image copyright Thinkstock
Tuberculosis now ranks alongside HIV as the world's most deadly infectious disease, the World Health Organization (WHO) says.
Each accounted for between 1.1 million and 1.2 million deaths in 2014.
The WHO said the tuberculosis figures were unacceptable for a disease that could be cured.
Medecins Sans Frontieres said the statistics were "disheartening" and warned the world was "losing ground" on tackling resistant forms of TB.

Heat-triggered 'grenades' hit cancer

Heat-triggered 'grenades' hit cancer

  • 31 October 2015
  • From the section Health
Liposomes
Image copyright Kostas Kostarelos
Image caption The scientists use liposomes to carry toxic drugs into tumours
Scientists have designed microscopic "grenades" that can explode their cancer-killing payload in tumours.
The team will present its findings at the National Cancer Research Institute conference next week.
They plan to use liposomes - tiny bubbles of fat which carry materials round the body - to release toxic drugs when their temperature is raised.

Milestone' prostate cancer drug

Milestone' prostate cancer drug

  • 29 October 2015
  • From the section Health
 Prostate cancer cell
Image copyright SPL
The first drug that targets precise genetic mutations in prostate cancer has been shown to be effective in a "milestone" trial by UK scientists.

The Magic of Chemistry - with Andrew Szydlo

            





The Magic of Chemistry - with Andrew Szydlo



Δημοσιεύτηκε στις 4 Ιουν 2014
Subscribe for the latest science videos: http://www.youtube.com/subscription_c...

If
you were able to make a substance change colour, or turn from a solid
to a liquid, would that be magic? In this Ri event from Wednesday 23
April 2014, Andrew Szydlo leads us through a world of magical molecules
and enchanting elements. From a liquid that boils at room temperature to
gases that are heavier than air, this family event is full of practical
demonstrations of the magic of chemistry.

Watch more science videos on the Ri Channel http://richannel.org
The Ri is on Twitter: http://twitter.com/ri_science
and Facebook: http://www.facebook.com/royalinstitution
Sign upfor the latest science videos: http://richannel.org/newsletter


ANAΡΤΗΣΗ ΑΠΟ ΤΟ YOUTUBE 1/11/2015




Levitating Superconductor on a Möbius strip

               

Levitating Superconductor on a Möbius strip



Δημοσιεύτηκε στις 26 Ιουν 2013
Andy
takes a closer look at one of his favourite demos from the 2012
Christmas Lectures, bringing together a levitating superconductor and a
bewildering Möbius strip made from over 2,000 magnets.

As his
super-conducting boat whizzes along the track, Andy demonstrates the
remarkable properties of the superconducting material (Yttrium barium
copper oxide) which allows it to seemingly float both above and below
the track.

Watch more science videos on the amazing Ri Channel: http://richannel.org

The Ri is on Twitter: http://twitter.com/ri_science
and Facebook: http://www.facebook.com/royalinstitution
Subscribe for the latest science videos: http://richannel.org/newsletter
ANAΡΤΗΣΗ ΑΠΟ ΤΟ YOUTUBE 1/11/2015




The Hidden Order of Complex Ecosystems

              





The Hidden Order of Complex Ecosystems





Δημοσιεύτηκε στις 18 Σεπ 2015
2015 Stanislaw Ulam Memorial Lecture Series
September 15, 2015

Dunne
shares surprising findings from her research of food webs, the networks
of who eats whom in nature. After revealing hidden ecological order,
she explores the underlying forces that constrain and organize
ecosystems across hundreds of millions of years, from the explosion of
biodiversity in the deep-time Cambrian period, long before the
dinosaurs, to the deteriorating condition of ecosystems in the present
day. She then describes characteristics that can fortify ecosystems
against species loss and environmental change.
ANAΡΤΗΣΗ ΑΠΟ ΤΟ ΥΟUTUBE 1/11/2015






Advancing the Journey to Mars on This Week @NASA – October 30, 2015

               



Advancing the Journey to Mars on This Week @NASA – October 30, 2015



Δημοσιεύτηκε στις 30 Οκτ 2015
During
an Oct. 28 keynote speech at the Center for American Progress, in
Washington, NASA Administrator Charlie Bolden spoke about the
advancement made on the journey to Mars and what lies ahead for future
administrations and policy makers. NASA’s recently released report
“Journey to Mars: Pioneering Next Steps in Space Exploration,” outlines
its plan to reach Mars in phases – with technology demonstrations and
research aboard the International Space Station, followed by hardware
and procedure development in the proving ground around the moon, before
sending humans to the Red Planet. Also, Space station spacewalk, Another
record in space for Kelly, Mars Landing Sites/ Exploration Zones
Workshop, Cassini’s “deep dive” flyby and more!
ANAΡΤΗΣΗ ΑΠΟ ΤΟ ΥΟUTUBE 1/ 11/2015

NASA | Webb Space Telescope Integrated Science Instrument Module begins ...

                   



NASA | Webb Space Telescope Integrated Science Instrument Module begins ...





Δημοσιεύτηκε στις 28 Οκτ 2015
Engineers
place the heart of the James Webb Space Telescope into the Space
Environment Simulator, a giant thermal vacuum and cryogenic testing
chamber, at NASA's Goddard Space Flight Center in Greenbelt, Maryland.

This video is public domain and can be downloaded at: https://svs.gsfc.nasa.gov/cgi-bin/sea...

You can find out more information at: Nasa.gov/jwst

Like our videos? Subscribe to NASA's Goddard Shorts HD podcast:
http://svs.gsfc.nasa.gov/vis/iTunes/f...

Or find NASA Goddard Space Flight Center on Facebook:
http://www.facebook.com/NASA.GSFC

Or find us on Twitter:
http://twitter.com/NASAGoddard
ANAΡΤΗΣΗ ΑΠΟ ΤΟ YOUTUBE 1/11/2015








Halloween Asteroid is a Radar Science Treat

            

Halloween Asteroid is a Radar Science Treat



Δημοσιεύτηκε στις 29 Οκτ 2015
JPL
scientist Marina Brozovic explains how radar will be used to study
asteroid 2015 TB145 when it safely passes Earth on Oct. 31, 2015.
Scientists are tracking the Halloween flyby with several optical
observatories and the radar capabilities of the agency's Deep Space
Network at Goldstone, California. Radar images should be available
within a few days of the flyby.
The asteroid will fly past Earth at a
safe distance slightly farther than the moon's orbit on Oct. 31 at
10:01 a.m. PDT (1:01 p.m. EDT). Scientists are treating the flyby of the
estimated 1,300-foot-wide (400-meter) asteroid as a science target of
opportunity. Full story at http://www.jpl.nasa.gov/news/news.php...

Are Old Galaxies Really Red and Dead? - Leo Blitz (SETI Talks)

                  



Are Old Galaxies Really Red and Dead? - Leo Blitz (SETI Talks)





Δημοσιεύτηκε στις 30 Οκτ 2015
Galaxies
are broadly divided into two classes: spiral and elliptical. Unlike the
spirals, the ellipticals, often referred to as early-type galaxies, are
largely composed of old stars that give them a reddish color, They
typically have little interstellar material with which to form new
stars; these galaxies are often referred to as “red and dead.” We will
see, however, that a substantial fraction of these galaxies contain
surprising amounts of neutral hydrogen and these do form stars, albeit
at a reduced rate compared to their spiral cousins. Early-type galaxies
outside of clusters can be seen to be accreting gas from their
surroundings, which is the source of at least some of the gas fueling
star-formation taking place within them. In addition, the galaxies are
seen to contain super-massive black holes in their centers. The black
holes appear to be responsible for ejecting much of the gas that falls
into the nuclei of these galaxies, reenergizing the intergalactic
medium.
ANAΡΤΗΣΗ ΑΠΟ ΤΟ YOUTUBE 1/11/2015




Imaging a habitable planet at Alpha Centauri - Ruslan Belikov (SETI Talks)

              



Imaging a habitable planet at Alpha Centauri - Ruslan Belikov (SETI Talks)







Δημοσιεύτηκε στις 26 Οκτ 2015
In
1990, at the request of Carl Sagan, Voyager 1 turned and took a picture
of Earth from a distance of 6 billion kilometers. This produced the
famous “pale blue dot” image of our planet. Several mission concepts are
being studied to obtain similar images of Earth-like exoplanets
(exo-Earths) around other stars. It is commonly thought that directly
imaging a potentially habitable exoplanet requires telescopes with
apertures of at least 1 meter, costing at least $1B, and launching no
earlier than the 2020s. A notable exception to this is Alpha Centauri (A
and B), which is unusually close for a Sun-like star. A ~30-45cm
visible light space telescope equipped with a modern high performance
coronagraph is sufficient to resolve the habitable zone at high contrast
and directly image any potentially habitable planet that may exist in
the system.

Dr. Belikov will describe the challenges involved
with direct imaging of Alpha Centauri planetary systems with a small
telescope and how new technologies currently being developed can solve
them. He will also show examples of small coronagraphic mission concepts
currently being developed to take advantage of this opportunity, and in
particular a mission concept called “ACESat: Alpha Centauri Exoplanet
Sattellite” submitted to NASA’s small Explorer (SMEX) program in
December of 2014.
ANAΡΤΗΣΗ ΑΠΟ ΤΟ YOUTUBE 1/11/2015


Domestic Water Purifier Supplier - Mars Water Technology Ltd.

              

Domestic Water Purifier Supplier - Mars Water Technology Ltd.





Δημοσιεύτηκε στις 4 Οκτ 2013
Mars
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What is Dark Matter ( HD Space Documentary )

                     



What is Dark Matter ( HD Space Documentary )





Δημοσιεύτηκε στις 14 Ιουλ 2015
What is Dark Matter ( HD Space Documentary )
Dark
matter is a hypothetical kind of matter that cannot be seen with
telescopes but would account for most of the matter in the universe. The
existence and properties of dark matter are inferred from its
gravitational effects on visible matter, radiation, and the large-scale
structure of the universe. Other than neutrinos, a form of hot dark
matter, it has not been detected directly, making it one of the greatest
mysteries in modern astrophysics.

Dark matter neither emits nor
absorbs light or any other electromagnetic radiation at any significant
level. According to the Planck mission team, and based on the standard
model of cosmology, the total mass–energy of the known universe contains
4.9% ordinary matter, 26.8% dark matter and 68.3% dark energy.[2][3]
Thus, dark matter is estimated to constitute 84.5% of the total matter
in the universe, while dark energy plus dark matter constitute 95.1% of
the total mass–energy content of the universe.[4][5][6]

Astrophysicists
hypothesized dark matter because of discrepancies between the mass of
large astronomical objects determined from their gravitational effects
and the mass calculated from the observable matter (stars, gas, and
dust) that they can be seen to contain. Dark matter was postulated by
Jan Oort in 1932, albeit based upon flawed or inadequate evidence, to
account for the orbital velocities of stars in the Milky Way and by
Fritz Zwicky in 1933 to account for evidence of "missing mass" in the
orbital velocities of galaxies in clusters. Adequate evidence from
galaxy rotation curves was discovered by Horace W. Babcock in 1939, but
was not attributed to dark matter. The first to postulate dark matter
based upon robust evidence was Vera Rubin in the 1960s–1970s, using
galaxy rotation curves.[7][8] Subsequently many other observations have
indicated the presence of dark matter in the universe, including
gravitational lensing of background objects by galaxy clusters such as
the Bullet Cluster, the temperature distribution of hot gas in galaxies
and clusters of galaxies and, more recently, the pattern of anisotropies
in the cosmic microwave background. According to consensus among
cosmologists, dark matter is composed primarily of a not yet
characterized type of subatomic particle.[9][10] The search for this
particle, by a variety of means, is one of the major efforts in particle
physics today.[11]

Although the existence of dark matter is
generally accepted by the mainstream scientific community, some
alternative theories of gravity have been proposed, such as MOND and
TeVeS, which try to account for the anomalous observations without
requiring additional matter. However, these theories cannot account for
the properties of galaxy clusters.[12]
ANAΡΤΗΣΗ ΑΠΟ ΤΟ YOUTUBE 31/10/2015




The Blackett Colloquium: Dark Matter

            



The Blackett Colloquium: Dark Matter





Ζωντανή μετάδοση στις 24 Οκτ 2015
The
Blackett Colloquium is an opportunity to hear about the work being
undertaken by Imperial scientists in the Department of Physics.

Dark
matter is one of the biggest mysteries in the whole of physics.
Astrophysical observations and theoretical ideas convincingly point to
the existence of a new type of particle. This particle makes up a
quarter of the contents of the universe, equivalent to five times more
than normal matter, yet the dark matter particle has eluded direct
observation - thus far.

Presentations will come from:

Dr Roberto Trotta (Senior Lecturer in Astrophysics, author of 'The Edge of the Sky')
Dr Henrique Araujo (experimental astroparticle physicist with the High Energy Physics group)
Dr Sarah Malik (researcher attached to the Large Hadron Collider Physics Centre)
Professor Tom Welton (Dean of the Faculty of Natural Sciences) Professor Jordan Nash (Head of Department of Physics).

Space, science and security

            

Space, science and security



Ζωντανή μετάδοση στις 28 Οκτ 2015
With
so much of our modern world and its infrastructure reliant on space
assets – from navigation to telecommunications, earth observation,
environmental monitoring and weather forecasting – we have become
vulnerable to many threats that could have economic and national
security consequences. The UK government policy on space security
published in 2014 sought to meet these challenges by making the UK more
resilient to disruption of space assets whilst enabling UK industry and
academia to exploit science and grasp commercial opportunities in
support of national space security interests.

The UK is not
alone in seeking to ensure effective, reliable and efficient access to
space based capabilities and promoting its own industrial and academic
science & technology base. The UK has many successful companies and
university groups contributing to innovation and wealth creation,
continually punching above its weight with industrial turnover running
at almost £12bn per year.

Space is the ultimate ‘global
commons’, and its use and exploitation is governed by UN treaty. But in
recent years the problem of space pollution, including debris from
accidental and deliberate satellite destruction, as well as concerns
over hostile counter-space programmes (e.g. navigation jamming,
communications interception), has become a cause of concern.

The
lecture will address these and other issues in space security. It will
consider ways in which a safe and secure space environment can be
sustained and how we must work with partners and the wider community to
promote codes of conduct. It will also explore opportunities for UK
industry and academia in space security.

Interact via the hashtag #securespace on social media.

David
Willetts is Executive Chairman of the Resolution Foundation and a
Visiting Professor at King's College London. He is Governor of the
Ditchley Foundation and a member of the Council of the Institute for
Fiscal Studies.

He was Minister for Universities and Science,
attending Cabinet, from 2010-2014. He was the Member of Parliament for
Havant from 1992-2015. Before that David worked at HM Treasury and the
Number 10 Policy Unit. He also served as Paymaster General in the last
Conservative Government.

David has written widely on economic and social policy. His most recent book 'The Pinch' was published by Atlantic Books.

About the Vincent Briscoe lecture

The
Institute for Security Science and Technology’s annual lecture is named
in honour of H.V.A. (Vincent) Briscoe, Professor of Inorganic Chemistry
at Imperial College London from 1932–55.

Records indicate
Briscoe provided the first independent scientific advice to the Security
Service in 1915, on the subject of secret German writing, and continued
in service throughout the inter-war years and during and after the
Second World War.
ANAΡΤΗΣΗ ΑΠΟ ΤΟ YOUTUBE 31/10/2015






Πέμπτη 29 Οκτωβρίου 2015

The Most Radioactive Places on Earth

            

The Most Radioactive Places on Earth





Δημοσιεύτηκε στις 17 Δεκ 2014
Who on Earth is exposed to the most ionizing radiation?
Check out Audible: http://bit.ly/AudibleVe
I'm
filming a documentary for TV about how Uranium and radioactivity have
shaped the modern world. It will be broadcast in mid-2015, details to
come. The filming took me to the most radioactive places on Earth (and
some places, which surprisingly aren't as radioactive as you'd think).
Chernobyl and Fukushima were incredible to see as they present
post-apocalyptic landscapes. I also visited nuclear power plants,
research reactors, Marie Curie's institute, Einstein's apartment,
nuclear medicine areas of hospitals, uranium mines, nuclear bomb sites,
and interviewed numerous experts.

Notes about measuring radiation:
Sieverts
are a measure of 'effective dose' - that means they measure the
biological impact of the energy transferred to tissues from radiation.

Obviously I owe a debt to the fantastic chart made by xkcd, which inspired my visual approach to this video.
https://xkcd.com/radiation/

DOSES MAY VARY
The level of radiation varies widely around the world depending mainly on altitude and geology (excluding nuclear accidents).

Estimates of particular doses also vary. All numbers reported in this video should be taken as order of magnitude only.

The
most contentious claim may be that smokers receive the highest dose of
ionizing radiation. This is not a whole body dose, but a dose to the
lungs as specified in the video. References are here:
http://en.wikipedia.org/wiki/Health_e...
http://www.rmeswi.com/36.html

Special thanks to:
Physics Girl: https://www.youtube.com/physicswoman
MinutePhysics: https://www.youtube.com/minutephysics
Natalie Tran: https://www.youtube.com/communitychannel
Bionerd23: https://www.youtube.com/bionerd23
Nigel and Helen for feedback on earlier drafts of this video.

Music is "Stale Mate"
ANAΡΤΗΣΗ ΑΠΟ ΤΟ YOUTUBE 29/10/2015






The mysterious universe that science "give up"? -Space Documentary 2104 ...

            



The mysterious universe that science "give up"? -Space Documentary 2104 ...





Δημοσιεύτηκε στις 3 Δεκ 2014
The mysterious universe that science "give up"? -Space Documentary 2104 full movies [HD]

Have Gravitational Waves Been Discovered?!? | Space Time | PBS Digital S...

              

Have Gravitational Waves Been Discovered?!? | Space Time | PBS Digital S...



Δημοσιεύτηκε στις 22 Οκτ 2015
Has the last great prediction of Einstein's general relativity finally been verified?

Tweet at us! @pbsspacetime
Facebook: facebook.com/pbsspacetime
Email us! pbsspacetime [at] gmail [dot] com
Comment on Reddit: http://www.reddit.com/r/pbsspacetime

For
the past 90 years, the predictions laid out Einstein's general theory
of relativity have continued to be confirmed by experimental science.
The last hold out is gravitational waves - the idea that certain
gravitational events cause actual ripples in Spacetime. The problem is
that the effects are almost beyond microscopic, so they are incredibly
hard to detect. But have scientist done it? Have gravitational waves
finally been directly observed??? Watch the episode to find out.

Gravitational Waves Extra Credit:

Nature article on rumor:
http://www.nature.com/news/has-giant-...

Lawrence Krauss' tweet:
https://twitter.com/LKrauss1/status/6...

Comments:
Eshan Das
https://www.youtube.com/watch?v=EzZGP...

NOBUNAGA1991
https://www.youtube.com/watch?v=EzZGP...

aaroNiGHTS
https://www.youtube.com/watch?v=EzZGP...

Tim Pipp
https://www.youtube.com/watch?v=EzZGP...

Marse Petrarse
https://www.youtube.com/watch?v=EzZGP...

Procyon Beta
https://www.youtube.com/watch?v=EzZGP...

dentoncrimescene
https://www.youtube.com/watch?v=EzZGP...
ANAΡΤΗΣΗ ΑΠΟ ΤΟ YOUTUBE 29/10/2015



Δευτέρα 26 Οκτωβρίου 2015

Which Universe Are We In? - Documentary

              



Which Universe Are We In? - Documentary





Δημοσιεύτηκε στις 4 Σεπ 2015
BBC Documentary, Horizon
Which Universe Are We In?
#BBC #Documentary

Which Universe Are We In?

Imagine
a world where dinosaurs still walk the earth. A world where the Germans
won World War II and you are president of the United States. Imagine a
world where the laws of physics no longer apply and where infinite
copies of you are playing out every storyline of your life.

It sounds like a plot stolen straight from Hollywood, but far from it. This is the multiverse.

Until
very recently the whole idea of the multiverse was dismissed as a
fantasy, but now this strangest of ideas is at the cutting edge of
science.

And for a growing number of scientists, the multiverse is the only way we will ever truly make sense of the world we are in.

Horizon asks the question: Do multiple universes exist? And if so, which one are we actually in?
ANAΡΤΗΣΗ ΑΠΟ ΤΟ YOUTUBE 27/10/2015

BBC Documentary 2015 | What Happened Before the Big Bang | Documentary ...

                 





BBC Documentary 2015 | What Happened Before the Big Bang |  Documentary ...



Δημοσιεύτηκε στις 2 Οκτ 2015
BBC Documentary 2015 | What Happened Before the Big Bang | Documentary 2015 || Universe Documentary,
The
Big Bang theory is the prevailing cosmological model for the universe
from the earliest known periods through its subsequent large-scale
evolution. The model accounts for the fact that the universe expanded
from a very high density and high temperature state, and offers a
comprehensive explanation for a broad range of observed phenomena,
including the abundance of light elements, the cosmic microwave
background, large scale structure, and Hubble's Law. If the known laws
of physics are extrapolated beyond where they are valid, there is a
singularity. Modern measurements place this moment at approximately 13.8
billion years ago, which is thus considered the age of the universe.
After the initial expansion, the universe cooled sufficiently to allow
the formation of subatomic particles, and later simple atoms. Giant
clouds of these primordial elements later coalesced through gravity to
form stars and galaxies.

Since Georges Lemaître first noted, in
1927, that an expanding universe might be traced back in time to an
originating single point, scientists have built on his idea of cosmic
expansion. While the scientific community was once divided between
supporters of two different expanding universe theories, the Big Bang
and the Steady State theory, accumulated empirical evidence provides
strong support for the former. In 1929, from analysis of galactic
redshifts, Edwin Hubble concluded that galaxies are drifting apart,
important observational evidence consistent with the hypothesis of an
expanding universe. In 1965, the cosmic microwave background radiation
was discovered, which was crucial evidence in favor of the Big Bang
model, since that theory predicted the existence of background radiation
throughout the universe before it was discovered. More recently,
measurements of the redshifts of supernovae indicate that the expansion
of the universe is accelerating, an observation attributed to dark
energy's existence. The known physical laws of nature can be used to
calculate the characteristics of the universe in detail back in time to
an initial state of extreme density and temperature.

Space Documentary Asteroid | Asteroid Doomsday | Space Documentary

          



Space Documentary Asteroid | Asteroid Doomsday | Space Documentary

Δημοσιεύτηκε στις 5 Μαρ 2015
Space Documentary Asteroid , Asteroid Doomsday , Space Documentary,









Quantum Theory Made Easy [1]

             



Quantum Theory Made Easy [1]





Δημοσιεύτηκε στις 17 Ιουλ 2015
“Quantum
Theory Made Easy,” a series in which the concepts of quantum physics
are broken down for layaudiences in a more digestable manner. More
in-depth than most presentations for laypersons, but without the
mathematical rigour needed by a specialist in the field.
So, you've heard that light is a wave/particle. Now you get to find out how we know this!
In
this episode, we’ll be discussing the dual nature of light, starting
with a brief overview of how light was determined to be an
electromagnetic wave and what properties light was classically
associated with. From there, we’ll present the results of Planck’s
blackbody experiments and introduce the concept of quantization, which
was how this whole quantum mess was started in the first place. After
explaining how the quantum of action (h) works, we’ll move on to how it
showed up in experiments that challenged the wave picture of light, and
how Einstein, bremsstrahlung, and Compton, made it clear that light can
behave like a particle.
If you enjoyed this video, please give it a
like. If you want to help support the propagation of this material,
please press the “favorite” button, and if you’re feeling particularly
proactive, please share it on your social media of choice. And of
course, if you’re new to this channel, or have just been lurking about
but aren’t sure if you’re ready to commit, just take a risk and press
that subscribe button (there’s actually no risk involved. Like, at all.
Just subscribe already.)

Special thanks goes to the following resources for their (Fair-Use protected) material:

Best of Science
https://www.youtube.com/user/Best0fSc...

UC Berkeley
https://www.youtube.com/user/UCBerkeley

Stellardrone

If you want to support the creation of these videos, or just want to see your name appear at the end of them, click here: https://www.patreon.com/user?u=581251...

Κυριακή 25 Οκτωβρίου 2015

Why I Love Neutrinos - Georgia Karagiorgi

      



Why I Love Neutrinos - Georgia Karagiorgi



Δημοσιεύτηκε στις 22 Οκτ 2015
Georgi
Karagiorgi of Manchester University loves neutrinos as they are very
"stingy" in revealing their mysteris. Discovering their properties is
likened to a popular game.

Detecting Neutrinos with the NOvA Detector

            





Detecting Neutrinos with the NOvA Detector




Greenland ice sheet melts: Planetary Emergency Issued by NASA

               

Greenland ice sheet melts: Planetary Emergency Issued by NASA



Δημοσιεύτηκε στις 29 Αυγ 2015
SAN
FRANCISCO — Greenland's disappearing ice shifted gears in the past
decade, switching from shrinking glaciers to surface melting,
researchers reported here last week at the American Geophysical Union's
annual meeting.

Instead of losing ice where massive glaciers meet
the sea, Greenland now sends meltwater rushing into the ocean via a
vast network of lakes and rivers, according to several studies. The
results do not mean that glaciers have stopped their speedy flow, only
that surface melting now exerts a more powerful influence on ice loss,
researchers said.

"We no longer see giant icebergs calving" from
glaciers, releasing ice into the sea, said Lora Koenig, a glaciologist
at the National Snow and Ice Data Center, who led one of the new
studies. "The majority of water is coming from surface melt.
Greenland,
one of the largest ice sheets in the world, is melting. In fact, it is
melting ahead of schedule as the world warms. Scientists are working
hard to deepen their understanding of this ice sheet’s behavior so that
we can predict how fast and how much of the ice sheet will melt in the
coming decades and centuries.

It might seem obvious that in a
warming world, the Greenland ice sheet will melt. But, what seems
obvious and simple can be more complex when investigated more deeply.
With respect to Greenland, it is expected that warmer temperatures
increase melting but warmer temperatures can also mean more snowfall, as
there is more moisture in warm air which can then fall as snow. So, it
has been a question of which of these two competing processes would win
out. Would Greenland get smaller because of melting or would it grow as
more snow fell?

Over the past few years, the verdict has become
clear. The Greenland ice sheet is losing mass at an increasing rate. In
fact, Greenland currently contributes twice as much as the Antarctic to
rising sea levels.
A new study, just published in Nature Geoscience,
makes an important new contribution to our understanding of the forces
at play in Greenland. Dr Samuel Doyle and an international team captured
the wide-scale effects of an unusual week of warm, wet weather in late
August and early September, 2011. They found that weather cyclonic led
to extreme surface runoff – a combination of ice melt and rain – that
overwhelmed the ice sheet’s basal drainage system. This drive a marked
increase in ice flow across the entire western sector of the ice sheet
that extended 140 km into the ice sheet’s interior.
The cyclonic
weather system delivered heat and rain to the western edge of the
Greenland ice sheet and under these warm, wet, cloudy conditions the way
that the ice sheet receives energy for melt is very different to that
under the more typical clear sky conditions. As we all know from a
cloudy day, clouds block a certain amount of sunshine, but under certain
conditions they can absorb the outgoing longwave radiation and
re-radiate it back to the surface. This is why a cloudy night is often
warmer than when the sky is clear. The same thing happens on the ice
sheet.

In fact during the August 2011 weather event, melt
continued throughout both day and night creating exceptionally high
daily melt totals for this time of year. Moisture in the atmosphere also
reduces the rate at which the air cools as it rises over the ice sheet,
allowing warm temperatures and therefore melt and rain to attain
abnormally high elevations. The heat released by condensation and by
rain refreezing in the snowpack enhanced melt even further.
Even
given these factors, the water runoff from melt and rain did not exceed
mid-summer peak values when ice flow was relatively slow. This is
because the ice sheet’s drainage system continually adapts to melt
inputs: in mid-summer an efficient drainage system forms and the ice
sheet can easily accommodate high water inputs. This isn’t the case in
late summer though, as the drainage system rapidly freezes shut when air
temperatures fall below zero.
The influence of such intense
rainfall events has not, until now, been considered in assessments of
the melt and flow response of any ice sheet. This is an important
omission because cyclonic conditions are predicted to increase in the
future, therefore likely playing an increasing role in driving ice mass
loss from the Greenland ice sheet.
Since the 1980s when rainfall
measurements began in the west Greenland town of Kangerlussuaq, the
focus of the study, the proportion of precipitation now falling as
rainfall rather than snow has both increased and extended into the late
summer and autumn in line with increased circulation and moisture
availability within a warmer, more energetic atmosphere.
ANAΡΤΗΣΗ ΑΠΟ ΤΟ YOUTUBE 26/10/2015






What Scientists Are Seeing Over Greenland 4K

              

What Scientists Are Seeing Over Greenland 4K

Δημοσιεύτηκε στις 26 Σεπ 2015
Why
are scientists out flying over Greenland, drilling into its ice, and
monitoring it from space? The answer is that they see it as a bellwether
of future Earth.

Scientists are sampling, drilling, and flying
over this great island because they believe it may be a bellwether of
future Earth. Greenland is two million square kilometers of land… 81% of
which is covered by a giant central ice cap, the Inland Ice. Here is
2.8 million cubic kilometers of ice… layered and packed over the
millennia. Its thickest points lie beneath two massive ridges… the
northern at 3 kilometers thick, the southern at over 3.2 kilometers.

The
Inland Ice basin is framed by parallel mountain ranges. Its bedrock
basement floor is down near sea level… depressed by the weight of the
ice above it. If this ice sheet were to melt, the land beneath would be
underwater, dotted with small islands. Over time, with the weight
lifted, it would gradually rise. Today, the sheer mass of the Inland Ice
exerts a gravitational pull on surrounding oceans. This pull raises sea
levels all around the island.

In the event of extreme melting, a
recent study showed that sea levels would actually drop out to a
distance of about 1000 kilometers. More distance shores, however, would
experience an average global sea level rise of over 7 meters.
ANAΡΤΗΣΗ ΑΠΟ ΤΟ YOUTUBE 26/10/2015

The Strange Sounds of Earth's Auroral Kilometric Radiation

                

The Strange Sounds of Earth's Auroral Kilometric Radiation





Δημοσιεύτηκε στις 9 Οκτ 2015
Earth
can generate radio emissions in a natural way. The most intense of
these emissions is a phenomenon called Auroral Kilometric Radiation
(AKR). It is produced in the auroral zones at an altitude between 3000
and 20 000 kilometres. The radiation mainly comes from cyclotron
radiation from electrons orbiting around the magnetic field lines of the
Earth. The radiation has a frequency of between 50 and 500 kHz and a
total power of between about 1 million and 10 million watts.

Afterwards,
the sounds escape outward into space in a concentrated direction from
the magnetic field lines but cannot be detected from the Earth's surface
as the ionosphere actually shields us from this radiation, hence only
at a height of about 3 times the radius of the Earth can AKR be
detected, as they were by solar, geomagnetic and plasma physics
satellites such as NASA's such as the Fast Auroral Snapshot Explorer
(FAST) missions and ESA's Cluster mission (from which this recording is
from).

AKR intensifies during magnetic and auroral substorms so
you can use it as a remote indicator of geomagnetic activity. The Wide
Band (WBD) instrument on-board Cluster recorded this sound and made the
first direct determination of the locations of an AKR (courtesy of Prof.
D. Gurnett, University of Iowa).

According to the data of the
Cluster mission, it is beamed out in the cosmos in a narrow,
concentrated beam plane tangent to the magnetic field at the source. The
sound produced by playing AKR over an audio device has been described
as "whistles", "chirps", and even "screams".

All planets with a
magnetic field produce AKR, with the gas giants such as Jupiter,
Saturn, Neptune and Uranus having the strongest given that they have the
largest internal magnetic fields. Interestingly, given the energy
concentrated in the radio band emitted being on the order of megawatts
and higher it might be possible to detect the AKR from planets beyond
the solar system, hence opening up new insights into the geomagnetism of
exoplanets and perhaps acting as another tool to narrow down the
physical conditions on them, such as whether they are solid or gaseous
or to simply say with evidence that their may be aurora in the skies of
an extra-solar planet which I think is a wondrous thought!
ANAΡΤΗΣΗ ΑΠΟ ΤΟ YOUTUBE 26/10/2015






Life in the Universe #4: Planets Are Everywhere

            

Life in the Universe #4: Planets Are Everywhere

Δημοσιεύτηκε στις 23 Οκτ 2015
With
the launch of space telescopes like Kepler, humanity has been given a
new look at our place in the universe. Planets around other stars are
teeming in our galaxy. This video looks at and celebrates these
observations and looks to the future of exoplanet research.

Follow DeepAstronomy on Google+
http://google.com/+DeepAstronomy
http://google.com/+TonyDarnell

We also have a great Google+ Community, come share your thoughts and join the discussion!
https://plus.google.com/communities/1...
ANAΡΤΗΣΗ ΑΠΟ ΤΟ YOUTUBE 26/10/2015





Σάββατο 24 Οκτωβρίου 2015

National Graphene Institute - a video tour

            


National Graphene Institute - a video tour




Δημοσιεύτηκε στις 22 Οκτ 2015
Architect
Tony Ling outlines the main design features of this new centre for
investigating graphene and using the material to develop new
technologies.
ANAΡΤΗΣΗ ΑΠΟ ΤΟ YOUTUBE 25/10/2015









1.1 Biochemistry

          



1.1 Biochemistry



Ανέβηκε στις 31 Μαΐ 2011
Get the notes: http://www.lulu.com/product/paperback...
The
lecture notes for this and all numbered lectures are available at
Lulu.com, keyword PHRM203 or just follow the link. The notes do NOT
include Exam Reviews, Paramedic Pharm, Heart Sounds, or Chest Tubes.
ANAΡΤΗΣΗ ΑΠΟ ΤΟ YOUTUBE 24/10/2015