This photo from the new Dark Energy Camera, taken in September 2012, shows the barred spiral galaxy NGC 1365, in the Fornax cluster of galaxies, which lies about 60 million light years from Earth.
In physical cosmology and astronomy, dark energy is a hypothetical form of energy that permeates all of space and tends to accelerate the expansion of the universe. Dark energy is the most accepted hypothesis to explain observations since the 1990s that indicate that the universe is expanding at an accelerating rate. In the standard model of cosmology, dark energy currently accounts for 73% of the total mass–energy of the universe.
There is one source of inspiration that has earned the attention of poets, artists and scientists alike, the night sky. Whether it be for spiritual reasons, such as the Native Americans who believed the stars were a world for their ancestors, or for reasons as practical as sailors navigating this world; the stars have been a guiding source for humanity for centuries. Poets, such as Edgar Allen Poe in his poem Evening Star, have turned to the stars as companions and muses burning in the cold darkness of night. Painters have also been known to draw on the stars for artistic guidance. One of the most well known paintings in all of history, Van Gogh’s Starry Night, serves as a tribute to the awe inspiring beauty possessed by these heavenly bodies. However, what science has to say about the stars may quite possibly trump the examples listed above in both their poetic and artful natures.
“We are all made of star stuff”, this is a quote made famous by the late Carl Sagan. When he spoke this phrase Sagan was referring to the scientific theory that all matter was first created in a star. Science has revealed the stars as the origin of all atoms larger than hydrogen. There are few ideas more poetic or more artful than the suggestion that all matter, all life, has a common origin in one of these guiding lights burning brightly in the night sky.
This installation consists of a visual exploration of the romance and splendor embodied by this scientific theory. The work entitled Star Stuff is an installation of living phosphorescent bacterial photographs of the cosmos taken by the Hubble telescope. Each celestial form is comprised of billions and billions of genetically engineered E. coli that have grown in such a pattern that they form a photographic reproduction of a celestial object. The installation is meant to instill in the viewer a sense of wonderment and awe reminiscent of the emotions experienced by poets and artists as they gazed at the stars. Suggesting that the scientific view of the universe is not cold and passionless, that in actuality, it is deeply poetic.
This composite image shows a supernova within the galaxy M100 that may contain the youngest known black hole in our cosmic neighborhood. In this image, Chandra’s X-rays are colored gold, while optical data from ESO’s Very Large Telescope are shown in yellow-white and blue, and infrared data from Spitzer are red. The supernova is marked with a green circle.
SN 1979C was first reported to be seen by an amateur astronomer in 1979. The galaxy M100 is located in the Virgo Cluster about 50 million light years from Earth. This approximately 30-year age, plus its relatively close distance, makes SN 1979C the nearest example where the birth of a black hole has been observed, if the interpretation by the scientists is correct.
Data from Chandra, as well as NASA’s Swift, the European Space Agency’s XMM-Newton and the German ROSAT observatory revealed a bright source of X-rays that has remained steady for the 12 years from 1995 to 2007 over which it has been observed. This behavior and the X-ray spectrum, or distribution of X-rays with energy, support the idea that the object in SN 1979C is a black hole being fed either by material falling back into the black hole after the supernova, or from a binary companion.
The scientists think that SN 1979C formed when a star about 20 times more massive than the Sun collapsed. It was a particular type of supernova where the exploded star had ejected some, but not all of its outer, hydrogen-rich envelope before the explosion, so it is unlikely to have been associated with a gamma-ray burst (GRB). Supernovas have sometimes been associated with GRBs, but only where the exploded star had completely lost its hydrogen envelope. Since most black holes should form when the core of a star collapses and a gamma-ray burst is not produced, this may be the first time that the common way of making a black hole has been observed.
Credit X-ray: NASA/CXC/SAO/D.Patnaude et al, Optical: ESO/VLT, Infrared: NASA/JPL/Caltech
Barred Spiral Galaxy NGC 6217
This is the first image of a celestial object taken with the newly repaired Advanced Camera for Surveys (ACS). The camera was restored to operation during the STS-125 Servicing Mission to upgrade the NASA/ESA Hubble Space Telescope.
The barred spiral galaxy NGC 6217 was photographed as part of the initial testing and calibration of Hubble’s ACS. The galaxy lies 6 million light-years away in the north circumpolar constellation Ursa Major.
Credit: NASA, ESA and the Hubble SM4 ERO Team
Prof Peter Higgs, after whom the particle is named, wiped a tear from his eye as the teams finished their presentations in the Cern auditorium.
“I would like to add my congratulations to everyone involved in this achievement,” he added later.
“It’s really an incredible thing that it’s happened in my lifetime.”»
— Higgs boson-like particle discovery claimed at LHC
Exploring the Universe with gamma rays
The last decade has witnessed the birth of a new field of astronomy – Very High Energy (VHE) gamma ray astronomy – expanding wavelength coverage of astronomical instruments by another 10 octaves towards the highest energy radiation. These gamma rays are produced when high energy cosmic rays bump into interstellar gas, creating a bunch of elementary particles. Unlike charged cosmic rays, the gamma rays travel on a straight path and point back to the point in the sky where they were produced. Apart from serving as tracers of cosmic rays, speculation is that some VHE 6.2 Exploring the Universe with gamma rays gamma rays may result from decays of relic particles with have survived since the Big Bang, such as the mysterious dark matter particles; detection of such gamma rays would give first hints towards the nature of dark matter.
Very High Energy gamma rays are absorbed in the Earth’s atmosphere, creating a cascade of secondary elementary particles, most of which never reach the ground. Satellite instruments such as AGILE and Fermi (the former GLAST), now in orbit, detect gamma-rays before they enter the atmosphere, but their size is too small to capture enough of the highest-energy gamma rays.
After long development, a ground-based detection technique pioneered by the American Whipple telescope and perfected by the European-led H.E.S.S. and MAGIC instruments has brought a break-through: Imaging Atmospheric Cherenkov telescopes. These telescopes collect and image the bluish light emitted by the particle cascades created by a VHE gamma ray in the atmosphere. Light from a single VHE gamma ray illuminates a “light pool” of about 150 m radius on the ground, hence a single telescope will detect gamma rays incident upon an area of a few 10000 m2, compared to the sub-m2 area of satellite detectors. Latest generation Cherenkov telescope systems use multiple telescopes to provide stereoscopic viewing of gamma-ray induced particle cascades, for improved determination of impact direction and energy of a gamma-ray.
VHE gamma-ray astronomy is becoming part of mainstream astronomy, with surveys of the Galaxy revealing dozens of VHE gamma-ray emitting cosmic-ray accelerators. Objects discovered include supernova remnants, binary systems, pulsars, stellar associations and different species of active galaxies, hosting super-massive black holes at their centres.
Part of IC 2177
The Seagull Nebula (IC 2177) is huge. It measures 120’ by 40’. Within that area, nebulae and newly formed stars abound. This image, which combines 22 hours of exposures, shows reddish and orange emission nebulosity as well as blue reflection nebulae. The detached part of the Seagull Nebula to the south (lower left in this image) represents the bird’s head.
by Rakibul Hasan from Melbourne, Australia