For centuries, people have navigated at night by the stars, using them to determine position and speed as well as direction. as technology improved, society has turned its attention to other forms of navigation such as GPS. In the 14th century, the first clocks were invented, allowing society to break down the day into smaller increments. But in the depths of interstellar space, GPS and conventional clocks won’t work. Astronauts need another form of navigation and timekeeping that will work across deep space, something that’s just as reliable as atomic clocks and the most precise navigation systems, considering, missions are often highly time sensitive. With all this in mind, it seems as though the answer may lie among the stars themselves. 

What are neutron stars

Often times, stars that are much bigger than our sun will reach a point where they are unable to continue the processes of nuclear fusion and fusion (using hydrogen). When the hydrogen runs out, they start splitting apart larger and heaver elements in a final effort to create energy. When they reach the largest element they can split (iron), the star essentially runs out of fuel and the outer layers start to expand until the star dies in a fiery eruption known as a supernova. Neutron stars are the remains that are sometimes left behind from such an eruption. 

Neutron stars are extremely dense since the matter that used to make up the star is now compressed into a much smaller surface area. The matter is so densely packed that protons and electrons are forced together and combine to form neutrons. Neutron stars also spin very rapidly, using the energy from the supernova to fuel the rotations. The fastest neutron star spins 716 times every second. 

What are pulsars

Pulsars are a type of highly magnetic neutron star. They have jets of matter flowing out from either pole of the star at the speed of light that spin along with the star itself. These beams of light can sweep across the line of sight of our planet, making them appear to flicker from our point of view. However, pulsars don’t actually flicker. Think of a lighthouse. As the beam shifts across your line of sight, it appears to brighten for a moment before dimming and then brightening again. The same scenario occurs with pulsars. 

Pulsars spin extremely fast, just like neutron stars, but they need to get energy from that rotation from somewhere. Even though supernovae release a lot of energy, it’s not enough to sustain the pulsar over long periods of time. So, the pulsar often ends up pulling energy from a nearby star. It essentially “eats” the other star, stealing its matter and rotational energy over a period of time and using that energy to fuel itself. This explains why often times, pulsars are found with no other stars around them. 

How can pulsars be used for deep space travel?

When pulsars rotate, they do so at very specific intervals. The rotations are not random, and the beam of light passes through our line of sight regularly. This is important because they can be used as source to measure time. While they are not as accurate as atomic clocks, pulsars work better on longer scales (such as those needed for deep space missions). They don’t need calibration and there’s no time discrepancies to account for. 

This method of keeping time has already been tested by a group of international astronomers and was found to be surprisingly accurate. If the experiment can be modified to be even more reliable, it can be a very useful tool for the future of deep space missions.