The BBC gets an exclusive look at the upgraded machine helping to overhaul our understanding of the Universe.
Category: space – Page 514
The shape of the Milky Way
To understand the nature of our galaxy, astronomers had to look to distant island universes.
Turn your eyes toward the night sky and you will see a bright, hazy band of light cutting across the sky.
For millennia, observers speculated about the Milky Way’s true nature. The Greeks said the streak of haze in the sky was milk spurting from the breast of the goddess, Hera, Egyptians thought it was cows’ milk, and some Aboriginal Australians thought it was a river flowing through the sky.
Today, we know that we are looking along the plane of our spiral galaxy, consisting of at least 100 billion stars. But understanding the shape of the Milky Way proved elusive up until the 20th century. The problem is we can’t get a bird’s eye view of our galaxy because our solar system is buried within the galaxy. But with the invention of the telescope, photography, spectroscopy, and radio astronomy, we have uncovered the shape and size of our home galaxy — and our place among the billions of stars that make up our island universe.
Gravitational Waves Should Permanently Distort Space-Time
The first detection of gravitational waves in 2016 provided decisive confirmation of Einstein’s general theory of relativity. But another astounding prediction remains unconfirmed: According to general relativity, every gravitational wave should leave an indelible imprint on the structure of space-time. It should permanently strain space, displacing the mirrors of a gravitational wave detector even after the wave has passed.
Since that first detection almost six years ago, physicists have been trying to figure out how to measure this so-called “memory effect.”
“The memory effect is absolutely a strange, strange phenomenon,” said Paul Lasky, an astrophysicist at Monash University in Australia. “It’s really deep stuff.”
Titan’s largest crater might be the perfect cradle for life
Impacts on Saturn’s mysterious moon may have mixed water and organic molecules in a warm environment.
Physicists at the University of California, Irvine have demonstrated the use of a hydrogen molecule as a quantum sensor in a terahertz laser-equipped scanning tunneling microscope, a technique that can measure the chemical properties of materials at unprecedented time and spatial resolutions.
Next generation photonic memory devices are ‘light-written,’ ultrafast and energy efficient
Circa 2019
Light is the most energy-efficient way of moving information. Yet, light shows one big limitation: it is difficult to store. As a matter of fact, data centers rely primarily on magnetic hard drives. However, in these hard drives, information is transferred at an energy cost that is nowadays exploding. Researchers of the Institute of Photonic Integration of the Eindhoven University of Technology (TU/e) have developed a ‘hybrid technology’ which shows the advantages of both light and magnetic hard drives.
Ultra-short (femtosecond) light pulses allows data to be directly written in a magnetic memory in a fast and highly energy-efficient way. Moreover, as soon as the information is written (and stored), it moves forward leaving space to empty memory domains to be filled in with new data. This research, published in Nature Communications, promises to revolutionize the process of data storage in future photonic integrated circuits.
Data are stored in hard drives in the form of ‘bits’, tiny magnetic domains with a North and a South pole. The direction of these poles (‘magnetization’), determines whether the bits contain a digital 0 or a 1. Writing the data is achieved by ‘switching’ the direction of the magnetization of the associated bits.
Celebrating Hubble’s 32nd Birthday: A Magnificent View of an Unusual Collection of Five Galaxies
This menagerie includes three spiral-shaped galaxies, an elliptical galaxy, and a lenticular (lens-like) galaxy. Somehow, these different galaxies crossed paths in their evolution to create an exceptionally crowded and eclectic galaxy sampler.
Caught in a leisurely gravitational dance, the whole group is so crowded that it could fit within a region of space that is less than twice the diameter of our Milky Way.
The Milky Way is the galaxy that contains the Earth, and is named for its appearance from Earth. It is a barred spiral galaxy that contains an estimated 100–400 billion stars and has a diameter between 150,000 and 200,000 light-years.