Jocelyn Bell Burnell is an astrophysicist from Northern Ireland. As a postgraduate student in 1967, she discovered the first radio pulsar – a spinning neutron star. This was one of the most significant scientific achievements of the 20th century. Through the story of Jocelyn Bell Burnell, we will explore astronomy and the discovery that should have won her the Nobel prize.
Jocelyn Bell Burnell was born in 1943 in Belfast, Northern Ireland. Her father was an architect for the Armagh Observatory, where young Jocelyn spent much time as a child. At a young age she read books on astronomy and showed intense interest in the subject. She liked it so much she decided to study physics at Glasgow University and graduated in 1965. From there she went to Cambridge to do a PhD in astrophysics with her supervisor Anthony Hewish. It was during her PhD that she made one of the biggest discoveries in physics. For her PhD research, Bell Burnell built and operated an 81.5 Hz radio telescope which she used to study galaxies. These telescopes did not have the computer screens we have today, they would print out sheets of paper with data coming from the universe.
In 1967, while analysing literally miles of print-outs from the telescope, Bell Burnell noted a few unusual signals which she termed as “scruff”. These “bits of scruff” seemed to indicate radio signals that were fast and regular. Bell Burnell and her supervisor Hewish determined that these signals must have emerged from rapidly spinning, super-dense, collapsed stars, which are now known as pulsars. In 1974, Anthony Hewish was awarded the Nobel prize in physics for the discovery of pulsars, but Jocelyn Bell Burnell was overlooked. The decision not to award her with the prize was heavily criticised by prominent astronomers at the time. After this, Bell Burnell went on to win a number of awards for her scientific work.
In 2018, she was awarded the Special Breakthrough Prize in Fundamental Physics. Following the announcement of the award, she decided to give the whole of the £2.3 million prize money to help female, minority, and refugee students seeking to become physics researchers. Jocelyn Bell Burnell is still working in the field of astrophysics and astronomy at the University of Oxford.
What is astronomy?
Astronomy is the study of celestial bodies (objects in space), such as galaxies, planets, stars, moons, asteroids and comets. The people who spend their lives studying these objects in space (like Jocelyn Bell Burnell) are known as astronomers or astrophysicists.
Galaxies are huge, gravitationally bound systems that contain stars, planets, dark matter, nebula, black holes, white dwarf stars and red dwarf stars (we’ll hear more about these later). Galaxies can come in different shapes and sizes. Our own galaxy, the Milky Way is an example of a spiral galaxy.
Planets are celestial bodies that orbit our Sun and have three defining characteristics. In order to be a planet, the object must be:
- Massive enough to be rounded by its own gravity
- Not massive enough to cause fusion
- Gravitationally independent of its neighbours (i.e. planets do not orbit around other planets – they can only orbit around the Sun)
We live on earth, which is one of eight planets in our solar system. The eight planets, in order of distance from the Sun are: Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, Neptune. A handy mnemonic device (way of remembering) for the order of the planets is:
My Very Educated Mother Just Served Us Nachos.
Try at home!
Can you come up with your own sentence for remembering the names and order of the planets?
Other planets exist outside of our solar system – we call these exoplanets. There is a possibility that life exists on some of the exoplanets, scientists are working on finding it.
Stars are created when solar nebula shrink into a very small, tight cluster. This creates very high pressure and temperature which ultimately leads to a nuclear fusion reaction. Nuclear fusion is when hydrogen is converted to helium – which generates a lot of energy. This energy must go somewhere, and it is pushed out of the star in the form of electromagnetic radiation (heat, light, UV rays etc.). Our Sun is a star, which is why we get light and heat coming from it. Our Sun was created 4.6 billion years ago and is estimated to last for another 7 billion. We can think of the Sun like a giant nuclear power plant, generating enormous amounts of energy every second.
Moons are natural satellites that orbit around planets. Every planet in our solar system has at least 1 moon, and there are a total of 173 known moons in our solar system. Moons are thought to be created from the same material as their primary planet. Below, we can watch how our moon evolved over time.