A University of British Columbia astronomer with an international team has discovered the largest structures of dark matter ever seen. Measuring 270 million light-years across, these dark matter structures criss-cross the night sky, each spanning an area that is eight times larger than the full moon.
“The results are a major leap forward since the presence of a cosmic dark matter web that extends over such large distances has never been observed before,” says Ludovic Van Waerbeke, an assistant professor in the Dept. of Physics and Astronomy.
To glimpse the unseen structures, the team of French and Canadian scientists “X-rayed” the dark matter, an invisible web that makes up more than 80 per cent of the mass of the universe.
Venus, it turns out, is a planet of extraordinarily changeable and extremely large-scale weather. Bright hazes appear in a matter of days, reaching from the south pole to the low southern latitudes and disappearing just as quickly. This kind of ‘global weather’, unlike anything on Earth, has given scientists a new mystery to solve.
The cloud-covered world of Venus is all but a featureless, unchangeable globe at visible wavelengths of light. Switch to the ultraviolet and it reveals a truly dynamic nature. Transient dark and bright markings stripe the planet, indicating regions where solar ultraviolet radiation is absorbed or reflected, respectively.
In July 2007, the Venus Monitoring Camera (VMC) captured a series of images showing the development of a bright southern haze.
ESA’s Integral has made the first unambiguous discovery of high-energy X-rays coming from a rare massive star at our cosmic doorstep, Eta Carinae. It is one of the most violent places in the galaxy, producing vast winds of electrically-charged particles colliding at speeds of thousands of kilometres per second.
The only astronomical object that emits gamma-rays and is observable by the naked eye, Eta Carinae is monstrously large, so large that astronomers call it a hypergiant. It contains between 100–150 times the mass of the Sun and glows more brightly than four million Suns put together. Astronomers know that it is not a single star, but a binary, with a second massive star orbiting the first.
People across the western hemisphere may be surprised to see a rust-colored Moon in the sky in a few days - an ominous omen to ancient people but a more predictable occurrence now. Early on 21 February (the evening of the 20 February for observers in North and South America) will be this year’s first and only total eclipse of the Moon.
Bonus: unlike the solar equivalent, the whole event is safe to watch and needs no special equipment.
In a total lunar eclipse, the Earth, Sun and Moon are almost exactly in line and the Moon is on the opposite side of the Earth from the Sun. The Moon is full, moves into the shadow of the Earth and dims dramatically but usually remains visible, lit by sunlight that passes through the Earth’s atmosphere.
Scaled versions of Jupiter and Saturn orbiting a star 5000 light-years away, half as massive as the Sun, have been revealed from an effort involving a world-wide net of telescopes, including the UK's Liverpool Telescope on the Canary Islands.
This marks the first discovery of another system of planets that has striking similarities with our Solar System. Moreover, it suggests that such giant planets do not favour the single-life but are more likely to be found in family groups. The research is published in the 15th February issue of Science.
Whilst there are more than 250 planets now known, there are only about 25 such systems with multiple planets and the newly discovered system resembles our own Solar System more closely than any previously observed.
Detailed images from Hubble’s Near Infrared Camera and Multi-Object Spectrometer (NICMOS) reveal an infant galaxy, dubbed A1689-zD1, undergoing a firestorm of star birth as it comes out of the dark ages, a time shortly after the Big Bang, but before the first stars completed the reheating of the cold, dark Universe. Images from NASA’s Spitzer Space Telescope’s Infrared Array Camera provided strong additional evidence that it was a young star-forming galaxy in the dark ages.
“We certainly were surprised to find such a bright young galaxy 13 billion years in the past”, said astronomer Garth Illingworth of the University of California, Santa Cruz, USA and a member of the research team.
The elliptical galaxy NGC 1132 (Hubble picture and video below) belongs to a category of galaxies called giant ellipticals. NGC 1132, together with the small dwarf galaxies surrounding it, are dubbed a “fossil group” as they are most likely the remains of a group of galaxies that merged together in the recent past.
In visible light NGC 1132 appears as a single, isolated, giant elliptical galaxy, but this is only the tip of the iceberg.
Scientists have found that NGC 1132 resides in an enormous halo of dark matter
, comparable to the amount of dark matter usually found in an entire group of tens or hundreds of galaxies.
When the Herschel Space Observatory launches on an Ariane-5 rocket from the Guiana Space Centre, Kourou, French Guiana, in July 2008, astronomers will be able to examine some of the coldest objects in the universe.
Herschel will have the largest mirror of any space telescope — twice the size of the famous Hubble — that will detect the ‘glow’ of spacedust at around -250C, rather than the light from stars.
As well as being able to see star-forming regions very nearby in our own galaxy, it will be able to see galaxies forming when the universe was in its infancy, more than ten billion years ago.
It's the first space telescope to operate in the sub-millimetre part of the spectrum, between the far-infrared and microwaves.
For the first time ever, NASA will beam a song -- The Beatles' "Across the Universe" -- directly into deep space at 7 p.m. EST on Feb. 4.
The transmission over NASA's Deep Space Network will commemorate the 40th anniversary of the day The Beatles recorded the song, as well as the 50th anniversary of NASA's founding and the group's beginnings. Two other anniversaries also are being honored: The launch 50 years ago this week of Explorer 1, the first U.S. satellite, and the founding 45 years ago of the Deep Space Network, an international network of antennas that supports missions to explore the universe.
The transmission is being aimed at the North Star, Polaris, which is located 431 light years away from Earth. The song will travel across the universe at a speed of 186,000 miles per second. Former Beatle Sir Paul McCartney expressed excitement that the tune, which was principally written by fellow Beatle John Lennon, was being beamed into the cosmos.
Only 4% of the universe is made of known material - the other 96% is traditionally labelled into two sectors, dark matter and dark energy. Dr HongSheng Zhao at the University of St Andrews believes dark matter and its counterpart dark energy may be more closely linked than was previously thought.
Astronomers believe that both the universe and galaxies are held together by the gravitational attraction of a huge amount of unseen material, first noted by the Swiss astronomer Fritz Zwicky in 1933, and now commonly referred to as dark matter.
Dr Zhao reports that, "Dark energy has already revealed its presence by masking as dark matter 60 years ago if we accept that dark matter and dark energy are linked phenomena that share a common origin.”