Did you know that...

We sort out the celestial bodies!

Space is complex, large and filled with different celestial bodies that are easy to mix up. At Sweden's Space University, we do research on the celestial bodies, we even do experiments where we collide with asteroids to change their orbits.

What is what?

Do you know the difference between a meteoroid and a meteor? We asked the space professors!

A meteoroid is an object in space that can vary in size from a grain of sand to a boulder.

If a meteoroid falls from space and lands on Earth, it is called a meteorite.

If the meteoroid burns up as it enters Earth's atmosphere, it becomes a meteor that we see as a luminous streak in the sky.

An asteroid is a celestial body that is smaller than planets but larger than meteoroids. Asteroids are located in asteroid belts, which means they orbit around the sun.

A comet is a celestial body made up of ice, rocks, dust, and other particles. When a comet approaches the sun, the ice starts to melt and evaporate, creating a coma (a cloud of gas and dust) around the comet. The comet can also have a long tail of gas and particles that extends away from the sun.

Colliding with asteroids

Mikael Granvik, associate professor of space technology systems at Luleå University of Technology, was involved in a major project where they sent a spacecraft (DART) to collide with an asteroid. The purpose was to find out, whether or not, it was possible to change the orbit of an incoming asteroid which might threaten the Earth in the future. The asteroid, Dismorphos, is about 170 meters in diameter, and the spacecraft that collided with the asteroid was the size of a washing machine. By doing this, Mikael Granvik together with the rest of the research group successfully changed the asteroid's orbit.

Is there life on dwarf planets?

First and foremost, we need to clarify what a dwarf planet is. It may sound like a smaller planet, like Earth...but smaller. However, according to the International Astronomical Union (IAU), there are some criteria for something to be called a dwarf planet.

1. The celestial body must orbit around the sun.
2. It should be roughly spherical in shape.
3. It cannot be large enough to have cleared its orbit from other materials such as comets and asteroids.

Examples of dwarf planets in our solar system include Pluto and, of course, Ceres.

At Sweden’s space univeristy exciting space research is being carried out, such as launching space probes and colliding with asteroids to change their orbits so they do not collide with Earth. Of course, we also try to do some simpler things, such as finding signs of life on dwarf planets.

Our researchers have advanced in a selection process for a mission announced by the European Space Agency (ESA), which involves landing on the dwarf planet Ceres in 2036-2037.

Ceres belongs to the group of ocean worlds, a celestial body where large amounts of water exist or have existed. These types have become very interesting in research because it is the right condition for there to have been or even be life.

On the surface of a crater on the dwarf planet, there is organic material and an abundance of salts, salts that come from Ceres' interior. This means that researchers can analyse the material and learn how the chemistry looked in the earlier stages of the origin of life in the solar system.

It is not yet clear whether Luleå University of Technology will land on Ceres, the final candidate will be chosen in 2029.

Would you like to know more about the Northern Lights?

As Sweden's space university, it's natural that we conduct research on the Northern Lights, or aurora borealis as it's also called. Most people are probably familiar with how the spectacular light phenomenon looks - green, blue, or even red lights dancing across the night sky.

If we go back in time, the Northern Lights played a big role in many cultures. The phenomenon could be seen as something ominous, a sign of an impending war, plague, or death. The Vikings believed it was reflections from the shields worn by Valkyries, warrior women who had been slain in battle.

Thanks to research, we now know that the Northern Lights are neither warrior women nor an ominous sign. But how do they form and what is it that we're actually seeing? Well, the sun sends out a solar wind, a stream of charged particles, and when these particles reach Earth's magnetic field, they're pushed towards the poles. There, they collide with atoms and molecules in Earth's atmosphere, which causes the atoms to become energized, with their electrons "jumping up" to a higher energy level. This process is called excitation. When the atoms return to their normal state, they emit light, which is what we call the Northern Lights.

Did you know that the Northern Lights have different colours depending on which atom or molecule is involved in the excitation? Oxygen atoms create the classic green light that most of us associate with the Northern Lights. But it can also be blue or reddish if nitrogen atoms are involved.