“Capable of producing a beam of light so intense that it would be equivalent to the power received by the Earth from the sun focused onto a speck smaller than a tip of a pin, scientists claim it could allow them boil the very fabric of space – the vacuum.”
Posts tagged astronomy.
Black holes have captured the imagination of scientists and amateur enthusiasts for years. The idea of some dark entity out there in the far reaches of space sucking up anything and everything that ventures near with such power and force that even light can’t escape it’s clutches, both enthralls and terrifies. Thus, the idea of one moving close enough to our planet would seem good reason to hit the panic button. But, in some cases, it appears, it might not be such a bad thing, at least if it were very, very small. That’s what one small group of researchers has concluded after simulating the effects of one tiny black hole hitting and passing through the Earth, on a computer.
Scientists now have evidence that Jupiter’s core has been dissolving, and the implications stretch far outside of our solar system.
The Death Of Stars
Titan in color
Copyright: NASA/JPL/SSI/J. Major
Some Planets Are Alien Invaders
Some people reach for the stars, but the stars themselves seem to be reaching for the planets. Although Earth and its planetary neighbors were born with the sun, a new study says billions of stars in our galaxy likely grabbed planets from the depths of space. The finding may explain the puzzling presence of worlds located far from their suns and even suggests that our solar system could harbor a planet that lurks unseen well beyond Pluto.
Planets form from a disk of gas and dust orbiting a star and so should not exist beyond the disk’s edge. In recent years, however, astronomers have reported giant planets more than 100 sun-Earth distances from their stars—much farther out than Pluto, whose mean distance from the sun is 39.5 times greater than Earth’s.
New evidence supports the idea that we live in an area of the universe that is “just right” for our existence. The controversial finding comes from an observation that one of the constants of nature appears to be different in different parts of the cosmos.
If correct, this result stands against Einstein’s equivalence principle, which states that the laws of physics are the same everywhere. “This finding was a real surprise to everyone,” says John Webb of the University of New South Wales in Sydney, Australia. Webb is lead author on the new paper, which has been submitted to Physical Review Letters.
Even more surprising is the fact that the change in the constant appears to have an orientation, creating a “preferred direction”, or axis, across the cosmos. That idea was dismissed more than 100 years ago with the creation of Einstein’s special theory of relativity.
A powerful repulsion between normal matter and hidden pockets of antimatter could be an alternate explanation for the mysterious force known as dark energy, according to a controversial new theory.
In 1998 scientists discovered that the universe is not only expanding but that its expansion is accelerating.
This totally unexpected behavior has been called the “most profound problem” in physics, because our current understanding of gravity says that attractions between mass in the universe should be causing the expansion to slow down.
The leading theory to explain the accelerating expansion is the existence of a hypothetical repulsive force called dark energy. (Related: “New Galaxy Maps to Help Find Dark Energy Proof?”)
But in the new study, Massimo Villata, an astrophysicist at the Observatory of Turin in Italy, suggests the effects attributed to dark energy are actually due to a kind of “antigravity” created when normal matter and antimatter repel one another.
“Usually this repulsion is ascribed to a mysterious dark energy that would uniformly permeate the cosmos, but nobody knows what it is nor why it behaves this way,” Villata said in an email.
“We are replacing an unknown force caused by an unknown element with the repulsive gravity of the well-known antimatter.”
Could the number of wandering planets in our galaxy – planets not orbiting a sun — be more than the amount of stars in the Milky Way?
Free-floating planets have been predicted to exist for quite some time and just last year, in May 2011, several orphan worlds were finally detected. But now, the latest research concludes there could be 100,000 times more free-floating planets in the Milky Way than stars. Even though the author of the study, Louis Strigari from the Kavli Institute for Particle Astrophysics and Cosmology (KIPAC), called the amount “an astronomical number,” he said the math is sound.
“The Crab Nebula (also designated M1 or NGC 1952) is visible through small telescopes, which has allowed astronomers to observe its growth and evolution since the supernovae that created it became visible in 1054 CE. A pulsar was found in the center of the Crab in 1968. This rapidly rotating neutron star is the core of the star that went supernova to make the nebula. In the intervening decades, x-ray, gamma ray, and radio observations have mapped the region of the nebula closest to the pulsar. During that mapping, it became apparent that the Crab pulsar is one of the brightest sources of gamma rays observable from Earth.
Despite all of those observations, we still don’t fully understand the Crab’s precise gamma ray spectrum, particularly recently observed pulses of intense gamma radiation seen by the Fermi Gamma-ray Space Telescope. Existing models certainly do well at describing much of the complex interplay between the intense magnetic fields of the pulsar and the winds of charged particles flowing outward. But no single scheme seems sufficient to cover all the observed phenomena.
A potentially promising new model, proposed by F. A. Aharonian, S. V. Bogovalov, and D. Khangulyan, may fill in some of these blanks. It proposes that areas near the pulsar are acting as rapid particle accelerators, but don’t boost electrons and heavier particles to the same extent.”
Astronomers have confirmed the existence of a new class of planet: a waterworld with a thick, steamy atmosphere.
The exoplanet GJ 1214b is a so-called “Super Earth” - bigger than our planet, but smaller than gas giants such as Jupiter. Observations using the Hubble telescope now seem to confirm that a large fraction of its mass is water. The planet’s high temperatures suggest exotic materials might exist there.
“GJ 1214b is like no planet we know of,” said lead author Zachory Berta, from the Harvard Smithsonian Center for Astrophysics.