Most large celestial objects are found to be approximately spherical in shape, e.g. moons, planets and stars. This is because the cause and the dominating force in cosmic structure formation is gravity: a force which pulls mass in all directions equally. Another sphere is the celestial sphere – the heavens above us upon which we observe astronomical observations. This means that data collected on planetary surfaces or observed on in the sky live natively on the sphere.
If you’re considering applying for a PhD at MSSL and want to know more about what it’s really like, we’ve asked a couple of our new students about how they are finding life as a research student here at the lab. Luke and Monica answer your questions:
One of the main challenges in modern cosmology is to understand how the very low-density matter between galaxies (known as the inter-galactic medium, or IGM) came to be hot and ionized today, reaching temperatures of up to 10 million degrees. It hasn’t always been this way – after the Big Bang the Universe expanded and cooled, eventually reaching temperatures low enough for much of the Hydrogen and Helium plasma within it to combine and form a neutral atoms in a process known as recombination around 378,000 years after the Big Bang. After this, the expansion and cooling of the Universe continued for hundreds of millions of years, leaving it in a dark and increasingly cold state – an era cosmologists refer to as the ‘Dark Ages’.
Hi, I’m Ellis Owen and I’m a first-year PhD student in the Theoretical Astrophysics Group here at MSSL. My work is focused on the Epoch of Reionization, a time when the Universe was only a few hundred million years old, when the first stars were beginning to form.