Navigation by Pulsar

On the golden record that accompanies the Voyager spacecraft, there is a map showing the location of Earth.  It’s not a road map that you might pull out when navigating a city, but a 3D map showing the location of a star, the Sun, in a populous galaxy.  But just how would this map work? And more importantly, what are the map markers? If you notice the lines at the bottom left of the golden record image, they all intersect at a common center point.  This is the Sun, and the lines extend out showing relative distances to the nearest...

The How and Why of Planet Nine

It hasn’t been found yet – let me make that clear.  But with evidence that it should exist, astronomers are looking more closely at the proposed planet nine and how it might have formed, and how it could have ended up in such a distant orbit. When you start to think about how a planet ten times the mass of Earth could have ended up more than ten times as far from the Sun as Neptune, a few scenarios pop into mind: It was formed in the inner solar system, where interactions with gas giants or another star pulled it out It formed...

Black Hole Eats and Erupts!

The only reason we can see black holes in the universe is because some of them swallow up gas and dust.  This heats up material that is spinning rapidly around the black hole as it falls in (called an accretion disk), and produces massive jets of material due to conservation of angular momentum that can be seen across the universe.  The energy released in the jets and the energy given off in the accretion disk are proportional to how much gas and dust is being consumed by the black hole.  More matter = more food = more energy released.  But...

Massive Stars Colliding!

News always reports the records.  The biggest, the loudest, the fastest, the first.  When it comes to Astronomy, there are so many new worlds to explore and so much new science to learn, we end up breaking records often.  Even with Astronomy being the oldest science, the sheer amount of stuff in the universe means there is always something new and surprising to discover. Today’s episode of ‘Biggest, brightest, hottest’ brings us the move massive binary star system ever found, with two huge, hot stars so close together that they are actually touching, merging their atmospheres together. In the Large...

Is Gravity the Same Everywhere?

One of the big questions in astrophysics is about variation of the laws of Physics.  The laws we know and are familiar with; angular momentum, gravity, energy, are the same everywhere on Earth.  But what about beyond Earth? The universe is so large and so vast, we may be in a local region where the laws of Physics are set, and our laws may be different from a distinct region somewhere else in the universe. The good news is that we can make predictions based on our understanding of physics. And with our powerful telescopes that allow us to view a variety of...

Uncanny Alignment Across Billions of Light Years

Quasars are Galaxies with incredibly massive Black Holes at their centre.  These Black Holes are fuelled by a swirling disc of material that can be ejected in a long jet along their axis of rotation, all due to the conservation of angular momentum.  This accretion disc can be so hot that it causes the central region of the Galaxy to shine more brightly than the entire Galaxy of stars surrounding it. A Belgian team using the Very Large Telescope (VLT) studied a population of 93 Quasars spread over Billions of Light-Years, and noticed that the rotation axes of the Quasars...

Hubble has nothing on ALMA: Planets forming around a star captured in finest detail ever

The Hubble Space telescope produced the finest Astronomical images in a generation, but Hubble’s time in the limelight has ended, and now it’s time for a new generation of both space- and ground-based telescopes to take over with their own jaw-dropping images and revolutionary science. Recently the Atacama Large Millimeter Array (ALMA) has taken the leap and used its full power to take an astonishing image of the protoplanetary disk of the young star HL Tau. This image is of a very young star, only about a million years old (Which is really young compared to the 4.5 billions year old...