Travelling in the Solar System

Urs Ganse, Erika Palmerio, and Eleanna Asvestari

(University of Helsinki)

March 24th, 2018


Photo credits: Alexandru Gegiuc

Traveling in space is so far from being easy that it actually is rocket science! But three enthusiastic space scientists from the University of Helsinki made it sound slightly less complicated on our last afternoon in The Science Basement.

Our first speaker Urs Ganse kicked off the event with Space Travel 101. Navigating a vessel in space is very different from, say, driving a car on the road, or flying an airplane in the atmosphere. Outside the earth’s atmosphere, spacecraft can only be steered by rockets oriented in different directions, that can be burst either to accelerate the spacecraft or change its axis. But steering towards a destination in space is not as straightforward as shown in Hollywood sci-fi flicks points out Urs, as the spacecraft is under the influence of gravitational forces that are fundamental to the fabric of space. Yes, the same forces by which each body in space attract one another. So due to this force, the spacecraft also needs to maintain its orbit to avoid crashing into the body that attracts it with the greatest amount of force. A spacecraft then can be maneuvered by changing the size of the orbit or by switching the body that it is orbiting around to reach the desired destination. However, when to change the orbit has to be precisely calculated to succeed (Check the full video below to watch Urs explain how it’s done).

Spacecraft not only use gravitational forces exerted by planets in the solar system to stay in orbit, but sometimes these forces can be used to boost its acceleration of a spacecraft or change the course of its direction- remember how Cooper, played by Matthew McConaughey, used Gargantua’s gravity to slingshot his spaceship Endurance to reach its destination in 2015 sci-fi Interstellar. This maneuver called “gravity-assist” has been used by many unmanned spacecraft, including two that made it beyond our solar system: Pioneer and Voyager. These unmanned spacecraft have allowed us to learn a lot about the planets in our solar system and the space it occupies. Erika Palmerio, the second speaker of the day, summarised all of the human effort expended to explore the solar system and also revealed what alien lives might learn about the life on earth in case they stumble upon Pioneer or Voyager (Check the video below).

For any successful trip, one needs to be wary of the dangers associated with the locale one’s getting into. When it comes to traveling in space, harmful radiation by ionized particles emitted by the sun or other stars in our galaxy, or by objects in foreign galaxies, called cosmic rays, is something we need to be aware of. Even if you’re not planning a trip to the moon this summer but a plane trip that takes polar route, cosmic rays can be a concern, warns Eleanna Asvestari. You can watch Eleana’s talk at the Afternoon in The Science Basement to learn more about cosmic rays below.

If science like this is your cup of tea, come join us in the Afternoon in The Science Basement. Follow our facebook page to stay updated on the speakers and the subjects of their talk.