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!
An image of Comet 46P/Wirtanen taken by Abel De Burgos Sierra from La Palma, in the Canary Islands, Spain, on 6 December 2018.
The comet nucleus is at the core of the brightest spot at the centre of the image, and the green diffuse cloud is its coma. The green colour is caused by molecules – mainly CN (cyanogen) and C2 (diatomic carbon) – that are ionised by sunlight as the comet approaches the Sun.
The comet reached perihelion, the closest point to the Sun along its orbit, on Wednesday 12 December, and is on the way to its closest approach to Earth this weekend, when it might become visible to the naked eye from dark locations.
A bright comet with a period of 5.5 years, 46P had been chosen in the 1990s as the target of ESA’s Rosetta mission. However, a launch delay prompted the mission team to select a new target, Comet 67P/Churyumov–Gerasimenko, which was visited by Rosetta between 2014 and 2016.
This image is a composite of three 10 second exposures using R, G, B filters on a Teleskop Service 130 f/5.7, using an Atik 460EX-M CCD. The field of view spans 58 arcmin x 46 arcmin.
Full story: December comet brings back Rosetta memories