Space and astronomy news
How will the Universe end? Right now cosmologists have two equally distressing scenarios mapped out for the long term fate of the Universe. On the one hand, gravity might slow down the expansion of our Universe so that it coasts to a stop and possibly even collapses back down into a Big Crunch. On the …
How will the Universe end? Right now cosmologists have two equally distressing scenarios mapped out for the long term fate of the Universe. On the one hand, gravity might slow down the expansion of our Universe so that it coasts to a stop and possibly even collapses back down into a Big Crunch. On the other hand, the expansion of the Universe could continue indefinitely thanks to the acceleration of dark energy. We would face a cold, lonely future as other galaxies fade away into the distance. My guest today is Eric Linder from the Lawrence Berkeley National Laboratory and he’s proposing experiments that could help us learn which of these two fates await us.
Although the Moon will be full, there will be plenty of excitement as we start the week with Mars and end with a wonderful conjunction of Saturn, Venus and Mercury. But that’s not all, for there are two comets and two galaxies to study as well a meteor shower. This will be a great week for all observers, so open your eyes to the skies because…
Here’s what’s up!
An international team of astrophysicists have developed a new theory to explain the accelerating expansion of the Universe, known as “dark energy”. Instead of a mysterious energy which is pushing matter apart at an accelerating rate, the team believes it could be the natural outcome of ripples in space and time created during the earliest moments of inflation after the Big Bang. These ripples could extend beyond what we can see with our telescopes, so we can only calculate their existence.
When developing his General Theory of Relativity, Albert Einstein predicted that the Earth should drag space and time around with it as it rotates on its axis. NASA’s Gravity Probe B spacecraft was launched earlier this year to help confirm this prediction, but an international team of researchers has beaten the spacecraft to a conclusion. By carefully tracking the position of the LAGEOS and LAGEOS 2 satellites – beachball-sized spheres covered in mirrors – they discovered that their orbit is being shifted by about two metres a year by this dragging effect by the Earth’s gravity, almost exactly what was predicted by Einstein.
Designed to test two of Einstein’s predictions about the nature of gravity and relativity, NASA’s Gravity Probe B spacecraft is about halfway through the initialization and checkout phase of its mission. Mission operators have transmitted more than 5,000 commands to the spacecraft, and everything seems to be functioning properly, including its gyroscopes and the targeting system that keeps it locked onto the guide star: IM Pegasi. If everything continues to go as planned, it should begin scientific operations in August, and deliver the final results in a year.
Researchers from Penn State University have developed a computer model that describes the interaction of a binary black hole system; where two black holes orbit one another. Previous models have fallen apart because the gravity of the black holes distorts the surrounding space so dramatically, it’s almost impossible to calculate. This unusual situation could generate gravity waves detectable from Earth, which so far have only been theorized by mathematicians.
It’s been a month since NASA launched the Gravity Probe B; an experiment designed to test Einstein’s predictions about gravity and relativity, and so far, the spacecraft is working well. It’s in the correct orbit and will begin the science phase of its mission next month. It will continue taking precise measurements of the Earth’s gravity over the next 13 months to test two predictions: how space and time are warped by our planet, and how the Earth drags space-time around with it as it rotates.
Researchers located a binary system in 2003, believed to be a spinning pulsar and a neutron star. But new evidence indicates that it’s actually two pulsars orbiting each other; the first known example of a binary pulsar system. Pulsars fire out a concentrated beam of radio radiation like a lighthouse – when this beam falls on the Earth, the pulsar looks brighter. In this system, one pulsar’s beam is illuminating the other pulsar, so it allows astronomers to accurately measure the interactions between the objects.
NASA has checked out its recently launched Gravity Probe B spacecraft, and everything seems to be working fine. The solar panels are producing enough power to run all of its electrical systems, and its communications systems are talking to operators on the ground. All four gyro suspension systems have been activated, and the gyros are now being prepared to gather scientific data. If all goes well, the spacecraft should confirm two predictions that Einstein made about general relativity: how the Earth bends space and time around it, and how it drags space and time as it rotates.