Dark Matter Is A Hypothetical Kind Of Matter That Cannot Be Seen With Telescopes But Would Account For

A special Astrophysics Documentary about Space, Time & our Universe.

A very interesting documentary about the Universe.

Spleens are strange organs, located on the upper-left side of the abdomen behind the stomach. They’re about the size and shape of an orange wedge, if the orange was squishy and full of blood. They’re relatively fragile, and because they contain so much blood, injuries can become serious.

A very informal poll of NPR employees, friends and random Uber drivers reveals that most people don’t have any idea what spleens are for. If they did know anything about spleens, it was this: You don’t need one to live.

The deep red, squishy spleen has been relegated to the organ bargain-basement, something to be cut out and discarded along with the appendix and wisdom teeth. But the spleen is seriously underrated, and we would like to give it a chance to redeem itself.

Meet The Spleen, The Strange Little Organ That Can Multiply

Image: Science Source

Buzz Aldrin inside the Gemini 12 spacecraft, November 13, 1966.

(NASA/University of Arizona)

How Close Are We To Nuclear Fusion?

“Naysayers love to claim that nuclear fusion is always decades away — and always will be — but the reality is we’ve moved ever closer to the breakeven point and solved a large number of technical challenges over the past twenty years. Nuclear fusion, if we ever achieve it on a large scale, will usher in a new era for humanity: one where energy conservation is a thing of the past, as the fuel for our heart’s desires will literally be without limits.”

The ultimate dream when it comes to clean, green, safe, abundant energy is nuclear fusion. The same process that powers the core of the Sun could also power everything on Earth millions of times over, if only we could figure out how to reach that breakeven point. Right now, we have three different candidates for doing so: inertial confinement, magnetic confinement, and magnetized target fusion. Recent advances have all three looking promising in various ways, making one wonder why we don’t spend more resources towards achieving the holy grail of energy.

A wormhole, or Einstein-Rosen Bridge, is a hypothetical topological feature that would fundamentally be a shortcut connecting two separate points in spacetime that could connect extremely far distances such as a billion light years or more, short distances, such as a few feet, different universes, and in theory, different points in time. A wormhole is much like a tunnel with two ends, each in separate points in spacetime.

For a simplified notion of a wormhole, space can be visualized as a two-dimensional (2D) surface. In this case, a wormhole would appear as a hole in that surface, lead into a 3D tube (the inside surface of a cylinder), then re-emerge at another location on the 2D surface with a hole similar to the entrance. An actual wormhole would be analogous to this, but with the spatial dimensions raised by one. For example, instead of circular holes on a 2D plane, the entry and exit points could be visualized as spheres in 3D space.

Stephen Hawking: 'If you feel you are in a black hole, don’t give up. There’s a way out.'

All is not lost if you fall into a black hole – you could simply pop up in another universe, according to Stephen Hawking.

The celebrated physicist has a new theory about where lost information ends up after being sucked into a black hole, a place where gravity compresses matter to a point where the usual laws of physics break down.

In a public lecture in Stockholm, Sweden, Prof Hawking said: “If you feel you are in a black hole, don’t give up. There’s a way out.” He said he had discovered a mechanism “by which information is returned out of the black hole”.

He was speaking at the KTH Royal Institute of Technology, where the Nordic Institute for Theoretical Physics (Nordita) is hosting the Hawking Radiation Conference dedicated to examining the mystery of the “information paradox” – a conundrum concerning what happens to things swallowed by black holes.

Information about the physical state of something disappearing into a black hole appears to be completely lost. But according to the way the universe works, this should be impossible. Even information falling into a black hole ought to end up somewhere.

According to Hawking, it does – in one of two ways. Either it is translated into a kind of “hologram” on the edge of the black hole, or it breaks out into an alternative universe.

In his lecture, reported in a blog from the KTH Royal Institute of Technology, he said: “The existence of alternative histories with black holes suggests this might be possible. The hole would need to be large and if it was rotating it might have a passage to another universe. But you couldn’t come back to our universe. So although I’m keen on space flight, I’m not going to try that.

“The message of this lecture is that black holes ain’t as black as they are painted. They are not the eternal prisons they were once thought. Things can get out of a black hole both on the outside and possibly come out in another universe.”

Hawking is director of research at Cambridge University’s department of applied mathematics and theoretical physics.

• This article was amended on 27 August 2015. An earlier version said the KTH Royal Institute of Technology was hosting the conference.

Record-Breaking Space Discoveries of 2016!

2016 was a lot of things, but for astronomers, it meant the discovery of some of the farthest, faintest, and youngest objects in the universe we’ve seen yet.

Ask Ethan #103: Have We Solved The Black Hole Information Paradox?

“How is Hawking’s theory of black holes storing information on the shell of an event horizon different than what Susskind said decades ago about black holes storing information on the shell of an event horizon? Did Hawking just pull a Steve Jobs and proclaim something new that Android figured out years before? Or is this actually new stuff?”

Stephen Hawking is claiming that the black hole information paradox has now been resolved, with the information encoded on the event horizon and then onto the outgoing radiation via a new mechanism that he’ll detail in a paper due out next month, along with collaborators Malcom Perry and Andrew Strominger. Only, that’s not really what’s happening here. While he does have a new idea and there is a paper coming out, its contents do not solve the information paradox, but merely provide a hypothesis as to how it may be solved in the future.

The Andromeda Galaxy (/ænˈdrɒmɨdə/), also known as Messier 31, M31, or NGC 224, is a spiral galaxy approximately 780 kiloparsecs (2.5 million light-years) from Earth.[4] It is the nearest major galaxy to the Milky Way and was often referred to as the Great Andromeda Nebula in older texts. It received its name from the area of the sky in which it appears, the constellation of Andromeda, which was named after the mythological princess Andromeda. Being approximately 220,000 light years across, it is the largest galaxy of the Local Group, which also contains the Milky Way, the Triangulum Galaxy, and about 44 other smaller galaxies.

The Andromeda Galaxy is the most massive galaxy in the Local Group as well.[7] Despite earlier findings that suggested that the Milky Way contains more dark matter and could be the most massive in the grouping,[12] the 2006 observations by the Spitzer Space Telescope revealed that Andromeda contains one trillion (1012) stars:[9] at least twice the number of stars in the Milky Way, which is estimated to be 200–400 billion.[13]

The Andromeda Galaxy is estimated to be 1.5×1012 solar masses,[7] while the mass of the Milky Way is estimated to be 8.5×1011 solar masses. In comparison, a 2009 study estimated that the Milky Way and M31 are about equal in mass,[14] while a 2006 study put the mass of the Milky Way at ~80% of the mass of the Andromeda Galaxy. The Milky Way and Andromeda are expected to collide in 3.75 billion years, eventually merging to form a giant elliptical galaxy [15] or perhaps a large disk galaxy.[16]

At 3.4, the apparent magnitude of the Andromeda Galaxy is one of the brightest of any Messier objects,[17] making it visible to the naked eye on moonless nights even when viewed from areas with moderate light pollution. Although it appears more than six times as wide as the full Moon when photographed through a larger telescope, only the brighter central region is visible to the naked eye or when viewed using binoculars or a small telescope.