Before the Big Bang

Researchers have developed a model of a shrinking universe that existed prior to the Big Bang. Image credit: NASA. Click to enlarge The Big Bang describes how the Universe began as a single point 13.7 billion years ago, and has been expanding ever since, but it doesn’t explain what happened before that. Researchers from Penn …

Modifying Gravity to Account for Dark Matter

Researchers at the University of St. Andrews and the Free University of Brussels think they have a solution that “fine-tunes” Einstein’s groundbreaking theory of gravity to help account for the effect of dark matter. Dr Hong Sheng Zhao and Dr Benoit Famaey have created a new formula that allows the strength of gravity to vary over galactic distances, perfectly matching observations made by astronomers.

World’s Largest Telescope

Europeans have begun funding what will eventually become the world’s largest telescope: the Square Kilometre Array. The first step is a four-year study that will consult astronomers and engineers from around the world to decide what will make the best design. It will then be developed in stages, with parts coming operational over the next decade, and completion by 2020. Once complete, this extremely sensitive radio telescope will help probe the nature of dark matter, confirm Einstein’s predictions about relativity… and let us watch television shows broadcast from nearby stars.

More Einstein Rings Discovered

Astronomers have turned up 19 new gravitationally lensed quasars using photographs from the Hubble Space Telescope and the Sloan Digital Sky Survey (SDSS). 8 of these are what are known as “Einstein’s Rings”, where a nearby galaxy and a more distant quasar are perfectly lined up from our vantage point. The nearby galaxy acts as a lens to gravitationally focus the light from the quasar to magnify our view of it.

Best View of the Milky Way’s Core

Astronomers have used the National Science Foundation’s continent-wide Very Long Baseline Array (VLBA), to peer deeper into the heart of the Milky Way than ever before. This image brings astronomers tantalizingly close the supermassive black hole believed to lurk there called Sagittarius A*. The strong pull of this black hole should create a distinctive shadow on the surrounding material, which should be visible if astronomers can double the sensitivity of this instrument.

Will the Universe Expand Forever?

What is the nature of the mysterious dark energy which is accelerating expansion of the Universe? In a recent study published in the Physical Review Letters, physicists are proposing two scenarios: thawing and freezing. In thawing, the expansion of the Universe should eventually come to a stop, and maybe even reverse. In “freezing”, the acceleration should continue indefinitely. A new mission: the Joint Dark Energy Mission (JDEM) has been proposed by NASA and the US Department of Energy, and should be able to determine which of these two scenarios is correct.

Audio: Unlikely Wormholes

Wormholes are a mainstay in science fiction, providing our heroes with a quick and easy way to instantly travel around the Universe. Enter a wormhole near the Earth and you come out on the other side of the galaxy. Even though science fiction made them popular, wormholes had their origins in science – distorting spacetime like this was theoretically possible. But according to Dr. Stephen Hsu from the University of Oregon building a wormhole is probably impossible.

What’s Up This Week – May 23 – May 29, 2005

Greetings, fellow SkyWatchers! The week might begin with a full Moon, but we’ll have plenty to explore as we learn about the anti-twilight arch and the “Belt of Venus”. We’ll watch as the Moon occults Antares, locate globular clusters, visit the planets and pinpoint asteroids. The weekend brings early dark skies along with challenges for all observers, so get ready to grab a comet by the tail, because…

Here’s what’s up!