The European Space Agency (ESA) is Europe’s gateway to space. Its mission is to shape the development of Europe’s space capability and ensure that investment in space continues to deliver benefits to the citizens of Europe and the world.
Find out more about space activities in our 23 Member States, and understand how ESA works together with their national agencies, institutions and organisations.
Exploring our Solar System and unlocking the secrets of the Universe
Go to topicProtecting life and infrastructure on Earth and in orbit
Go to topicUsing space to benefit citizens and meet future challenges on Earth
Go to topicMaking space accessible and developing the technologies for the future
Go to topicThank you for liking
You have already liked this page, you can only like it once!
Data from ESA’s star-observing satellite Gaia shows that the warped galactic disc of the Milky Way precesses, or wobbles, similarly to the motion of a spinning top. The warp moves around the centre of the Milky Way faster than previously expected, completing one rotation in 600 to 700 million years. That’s however, still slower than the speed at which the stars in the disc orbit the galactic centre. Our mother star, the Sun (shown in the animation as the small yellow dot), for example, requires only 220 million years to complete one orbit.
The speed of the warp’s precession led astronomers to believe that it must be caused by something rather powerful, such an ongoing collision with a smaller galaxy.