Dr Alastair Gunn
Alastair is a radio astronomer at the Jodrell Bank Centre for Astrophysics at the University of Manchester.
Recent articles by Dr Alastair Gunn
What is a wandering star?
Nope, they haven’t been booted out of for bad behaviour.
How many black holes are there in the Milky Way?
Let’s hope for all our sakes we don’t stumble across any…
What is Ashen light?
Trick of the light or naturally occurring phenomenon?
How can we still talk to Voyager 2, even though it’s billions of miles away?
In 2018, Voyager 2 became only the second human-made object to enter the space between the stars.
Doughnut plasma and 100 million°C cores: How scientists could soon make nuclear fusion a reality
What are the problems facing nuclear scientists in their quest for the ultimate clean energy source? A physicist explains.
Here's what would happen if you lit a firework in space
Without additional oxygen provided by Earth's atmosphere, fireworks wouldn't behave the same way as they do on Earth.
What is the doppler effect?
This fundamental concept in physics is why the Moon sometimes looks red, and can help doctors analyse blood flow in tissues.
Could an asteroid impact ever change Earth’s orbit?
The impact an asteroid could have on Earth depends on many things including velocity, angle and geology.
What is a dormant black hole?
Technically Sagittarius A*, the supermassive black hole at the centre of the Milky Way, is dormant.
How do the rocks stay on the surface of Dimorphos?
Dimorphos is a small moon that orbits the asteroid Didymos, and the target of NASA's DART mission in September 2022.
What is the closest planet to Earth, really?
There has recently been some confusion over which of the planets of the Solar System is closest to Earth.
A mysterious force keeps destroying the Universe’s lithium. And scientists don’t know why
Lithium is a soft, silvery-white alkali metal used in the manufacture of aircraft and batteries, but it's surprisingly rare.
What is chaos theory?
Because sometimes even scientists need an excuse for their messy desks.
Why does the Sun produce so much radiation?
Proposed fusion power plants will generate no radiation. So why does the Sun, which also uses fusion, produce so much?
If we colonise the Moon, will the colonists experience night and day?
When Artemis 3 lifts off, we'll be one step closer...
How do meteorites from Mars end up on Earth?
There are 60,000 recorded meteorites on Earth.
What would the sky look like if Earth revolved around a star in the centre of a globular cluster, like Messier 15?
A globular cluster is a stable, tightly bound collection of thousands, if not millions of stars.
How is colour added to the JWST images? An astronomer explains
The James Webb Space Telescope collects images in greyscale as it operates mostly in the near- and mid-infrared spectrum. So how are we seeing colour images?
Dyson spheres: How humans (and aliens) could capture a star’s energy
What is a Dyson sphere? How would a Dyson sphere work? Could they be responsible for strange signals from space?
What is a binary planet system?
If the Moon were bigger, at what point would it be deemed a planet and therefore the Earth and Moon a ‘binary planet’ system?
What would happen to our view of far-off galaxies, if we travelled at (or near) light-speed towards them?
If a star 1000 light-years away went supernova and died, it would take us 1000 years to know - but what if we were moving towards it, at (or near) light-speed?
How do solar flares affect the Earth?
Strong solar flares can release a stream of energetic subatomic particles that often give us spectacular auroral displays.
The Sun: Everything you need to know
The Sun is at the heart of our Solar System, and accounts for over 99 per cent of the total mass.
How does nuclear fusion work?
It could provide us with a clean, efficient and unlimited source of energy.