A closer look at a supernova confirms simulations that an asymmetric explosion is required to trigger stellar death.
Tag Archives | Astronomy
Jasmine Wright and Margaret Myers Via PBS.org:
… Read the rest
Hubble’s contributions to space exploration are countless. Its images, explains Hubble Space Telescope Senior Project Scientist Jennifer Wiseman, have shown the first definitive detection of supermassive black holes at the centers of galaxies. They also have provided measurement of the expansion rate of the universe, and detection (along with ground-based telescopes) of acceleration in that expansion, caused by mysterious “dark energy” that appears to be pushing the universe apart.
“Hubble will go down in history as having changed the textbooks by totally revolutionizing humanity’s view of the universe, and our place in it,” Wiseman says.
Iconic images of astronomical pillars of gas and dust, views of galaxies soon after they were formed, an accelerating universe driven by Dark Energy… “give us more!” say the public and the taxpayers. The Hubble Space Telescope is undoubtedly one of the most popular science projects today. It was not always thus.
Laying the groundwork
With its origins dating back to a time when almost all astronomers used photographic plates to record images at ground-based telescopes, the idea of an ambitious and expensive observatory in space was not a popular one.
The most influential astronomers of the 1960s thought it better to spend the money on 15 copies of the 200-inch giant on Palomar Mountain, rather than gamble all on a single telescope in space that was not as large.
Astronomers have found evidence of a giant void that could be the largest known structure in the universe. The “supervoid” solves a controversial cosmic puzzle: it explains the origin of a large and anomalously cold region of the sky. However, future observations are needed to confirm the discovery and determine whether the void is unique.
The so-called cold spot can be seen in maps of the Cosmic Microwave Background (CMB), which is the radiation left over from the birth of the universe. It was first discovered by NASA’s Wilkinson Microwave Anisotropy Probe (WMAP) in 2004 and confirmed by ESA’s Planck Satellite. For more than a decade, astronomers have failed to explain its existence. But there has been no shortage of suggestions, with unproven and controversial theories being put forward including imprints of parallel universes, called the multiverse theory, and exotic physics in the early universe.… Read the rest
Astronomers at Queen’s University Belfast have discovered an unbound star, US708, that is traveling at 1,200 kilometres per second. This is the fastest speed ever recorded in our galaxy.
The star is not bound by gravity and will eventually leave our galaxy. It is assumed that US708 was originally part of a “double-star” system, which included a massive white dwarf star. Presumably, the white dwarf exploded into a “thermonuclear supernovae,” or “type Ia supernova,” which kicked US708 out of orbit. A Type Ia Supernova occurs when two stars orbit each other “in which one of the stars is a white dwarf while the other can vary from a giant star to an even smaller white dwarf.”
Despite breaking a galactic record, the discovery of “US708 sheds light on the mysterious double-star systems that give rise to thermonuclear explosions. Thermonuclear, or ‘type Ia’, supernovae have long been used to calculate the distances to faraway galaxies – a measurement which helps to determine how the universe is changing and expanding.”
European Southern Observatory fellow, Stephan Geier, who led the study, said: “Several types of stars have been suspected of causing the explosion of a white dwarf as supernova of type Ia.… Read the rest
… Read the rest
Scientists have discovered the brightest quasar in the early universe, powered by the most massive black hole yet known at that time. The international team led by astronomers from Peking University in China and from the University of Arizona announce their findings in the scientific journal Nature on Feb. 26.
The discovery of this quasar, named SDSS J0100+2802, marks an important step in understanding how quasars, the most powerful objects in the universe, have evolved from the earliest epoch, only 900 million years after the Big Bang, which is thought to have happened 13.7 billion years ago. The quasar, with its central black hole mass of 12 billion solar masses and the luminosity of 420 trillion suns, is at a distance of 12.8 billion light-years from Earth.
… Read the rest
Cloud-like formations were originally spotted within the atmosphere of Mars by astronomers in 2012, leading some to believe the planet may be habitable or is being transformed in some way to make it so.
In fact images show the vapor formation to be over 621 miles across, which is larger than any other formation previously spotted within the red planet’s atmosphere to date.
A planetary scientist with the European Space Agency says this “raises more questions than answers”.
Damien Peach, an astronomer said, “I noticed this projection sticking out of the side of the planet. To begin with, I thought there was a problem with the telescope or camera. But as I checked more of the images, I realized it was a real feature – and it was quite a surprise.”
According to reports the haze lasted about 10-days before reemerging about 30-days later as it appears these new clouds are beginning to form in a more consistent manner than ever before, bringing only one thing to mind — the 1990 science fiction film Total Recall starring Arnold Schwarzenegger.
Jonathan Symcox via The Mirror:
… Read the rest
Scientists in the UK say this microscopic metal globe could be proof that aliens are watching us.
Balloons sent 27km into the stratosphere to collect debris came back with the object, no bigger than the width of a human hair.
Professor Milton Wainwright, leader of the joint study by the University of Buckingham Centre for Astrobiology and University of Sheffield, said the structure is made from titanium and vanadium metals and has a biological “gooey” substance oozing from it.
Scientists believe it could contain genetic material used to propagate alien life on Earth.
“It is a ball about the width of a human hair, which has filamentous life on the outside and a gooey biological material oozing from its centre,” he told the Daily Express website.
“We were stunned when X-ray analysis showed that the sphere is made up mainly of titanium, with a trace of vanadium.
Jayalakshmi K. via International Business Times:
… Read the rest
The high precision Planck data just released has placed the age of the universe at 13.77 billion years, besides showing that the first stars were born 550 million years after the Big Bang.
Data from four years of observation by ESA’s spacecraft shows 4.9% of the Universe to be made of ordinary matter, 25.9% dark matter and 69.2% dark, unknown energy.
The researchers calculate the current rate at which space is expanding to give the age of the universe.
The Planck collaboration, which includes the CNRS, the French Alternative Energies and Atomic Energy Commission (CEA), the French National Space Agency (CNES) and several French universities and institutions, aimed to study the Cosmic Microwave Background (CMB), the light left over from the Big Bang.
The Planck measurements, taken in nine frequency bands, were used to map not only the temperature of radiation but also its polarisation providing information about both the very early Universe (when it was 380,000 years old) and our Galaxy’s magnetic field.
… Read the rest
Reports of the death of the Big Bang have been greatly exaggerated. Big Bang theory is alive and well. At the same time, our universe may not have a beginning or end.
Are you seeing the stories this week suggesting that the Big Bang didn’t happen? According to astrophysicist Brian Koberlein – a great science communicator at Rochester Institute of Technology with a popular page on G+ – that’s not quite what the new research (published in early February 2015 Physics Letters B, has suggested. The new study isn’t suggesting there was no Big Bang, Koberlein says. It’s suggesting that the Big Bang did not start with a singularity – a point in space-time when matter is infinitely dense, as at the center of a black hole. How can this be? Koberlein explains on his website:
The catch is that by eliminating the singularity, the model predicts that the universe had no beginning.