European Space Agency Science Programme

The Science Programme of the European Space Agency is a long-term plan for exciting space science and exploration missions. It helps create, launch, and run important space missions led by European space agencies and research groups.

The first big plan, called Horizon 2000, started in 1985 and led to eight amazing missions by 1995. Some of these were very important, like SOHO, Cluster II, XMM-Newton, Rosetta, and Herschel.

A second plan, Horizon 2000 Plus, added more missions like Gaia, LISA Pathfinder, and BepiColombo between 1995 and 2005. Today, the current plan is called Cosmic Vision, started in 2005, and it has helped build ten missions so far, including big ones like JUICE, Athena, and LISA.

The next big plan, Voyage 2050, is still being made. Sometimes, the Science Programme works with other space agencies around the world, like with NASA on Cassini–Huygens and with the CNSA on SMILE.

Governance

The Science Programme is managed by the European Space Agency (ESA)'s Directorate of Science. Its goals are to grow Europe’s scientific work in space, encourage new technology, and keep Europe’s space tools like launches and spacecraft running. Every member state of ESA must join this programme. They pay an amount based on their net national product to help fund the programme and its missions for the long term.

Missions are chosen through contests. Scientists from Europe send ideas to ESA. ESA asks for ideas in four types of missions: big, medium, small, and fast, each with different budgets and time plans. The ideas are checked by science groups, engineers, and sometimes special teams. Up to three ideas become final choices. Then, ESA picks one to build, launch, and complete the mission.

History

Setbacks on a joint mission with the United States and the successes of a European rocket called Ariane 1 led to the start of an independent European program for space science.

Background

The European Space Agency (ESA) began in May 1975, combining two older organizations. In the 1970s, ESA decided not to focus on certain types of space missions, like studying stars or planets, because they seemed too expensive and complex at the time. This meant ESA needed to work with other countries and groups for bigger science projects. This changed in 1980 when ESA chose missions to study a comet and stars, marking the start of more independent space science efforts.

Horizon 2000

Formulation

In late 1983, ESA asked scientists across Europe for ideas for new space missions. They received many suggestions and grouped them into different sizes and costs. The biggest missions, called "cornerstones," included plans to study comets, X-rays from space, and submillimetre astronomy. These missions aimed to advance science, make Europe a leader in space research, and inspire new technology.

Implementation

The X-ray Multi-Mirror Mission was planned as one of the major projects. Over time, the mission was adjusted to make it more practical. Other missions, like studying planets around stars and gamma rays, were also selected and developed, sometimes working with other countries to share costs and resources.

Horizon 2000 Plus

Horizon 2000 Plus extended the original plan, adding more missions in the 1990s and 2000s. This included missions to map stars, explore Mercury, and test new technologies for future space telescopes. Most of these missions were successful, though one had to be redone after its launch failed.

Cosmic Vision

Main article: Cosmic Vision

Cosmic Vision is ESA's current plan for space science missions from 2015 to 2025. It focuses on big questions about planets, our solar system, the laws of physics, and the origins of the universe. Missions in this plan include studying Jupiter, the Sun, and dark matter, among other topics.

Large class

Large class missions are big projects led mainly by ESA. Three have been chosen so far: a mission to Jupiter and its moon Ganymede, an X-ray observatory, and a space-based observatory to study gravitational waves. ESA also plans a mission to explore Saturn's moons as the next big project.

Medium class

Medium class missions are smaller, standalone projects. Examples include missions to study the Sun, dark matter, and planets around other stars. These missions are chosen through a competitive process, with several being selected over the years.

Small class

Small class missions are the most budget-friendly, costing not more than 50 million euros. The first was a mission to look for planets around stars, followed by a mission to study Earth's magnetic field and solar wind.

Fast class

In 2018, ESA proposed a new type of mission called Fast class. These are special opportunities to study new topics, launched alongside bigger missions. The first Fast class mission will intercept a comet, and another will study distant objects in space.

Missions of Opportunity

Sometimes, ESA joins missions led by other space agencies. These "Missions of Opportunity" let ESA scientists take part in projects led by partners, usually for less money. ESA has contributed to missions studying the Sun, stars, and planets, among other topics.

Voyage 2050

The next big plan for ESA's science program is Voyage 2050, covering missions from 2035 to 2050. Planning started in 2018, and the plan includes big missions to study moons of giant planets, exoplanets, and the early universe. The first big mission will focus on Enceladus, a moon of Saturn. Three ideas for the first medium-sized mission are also being studied.

Missions

Horizon 2000

• Cornerstone 1 – SOHO, launched in December 1995 and still working – a joint mission between ESA and NASA to watch the Sun and help us understand space weather.
• Cornerstone 1 – Cluster, launched in June 1996 but did not succeed. A new version, Cluster II, was launched in 2000 and is working well, studying Earth's magnetic field with four spacecraft.
• Cornerstone 2 – XMM-Newton, launched in December 1999 and still working – a special telescope that looks at bright objects in space using X-ray light.
• Cornerstone 3 – Rosetta, launched in March 2004 and finished its job – a mission to study a comet called 67P/Churyumov–Gerasimenko and learn how comets change over time.
• Cornerstone 4 – Herschel, launched in May 2009 and finished – a telescope that looked at space using infrared light.

Other missions in this group include:

• Medium 1 – Huygens, launched in October 1997 and finished – landed on Titan, a moon of Saturn, which was the first landing far from Earth.
• Medium 2 – INTEGRAL, launched in October 2002 and finished – a telescope that looks at gamma rays, X-rays, and visible light.
• Medium 3 – Planck, launched in May 2009 and finished – mapped the oldest light in the universe to learn about its beginnings.

Horizon 2000 Plus

• Mission 1 – Gaia, launched in December 2013 and finished – measured the positions and distances of over a billion objects in our Milky Way galaxy.
• Mission 2 – LISA Pathfinder, launched in December 2015 and finished – tested new technologies for a future mission to study gravitational waves.
• Mission 3 – BepiColombo, launched in October 2018 and still working – a joint mission between ESA and JAXA to study the planet Mercury using two spacecraft.

Cosmic Vision

• L1 – JUICE, launched in April 2023 and will enter orbit around Jupiter in 2031 – studies Jupiter's moons Europa, Ganymede, and Callisto.
• L2 – Athena, will launch in 2035 – a new X-ray telescope to follow XMM-Newton.
• L3 – LISA, will launch in 2035 – the first mission dedicated to studying gravitational waves from space.
• M1 – Solar Orbiter, launched in February 2020 and still working – studies the Sun from close up.
• M2 – Euclid, launched in July 2023 and still working – looks at space using visible and infrared light to study dark matter and dark energy.
• M3 – PLATO, will launch in 2026 – will look for and study planets outside our solar system, similar to the TESS mission.
• M4 – ARIEL, will launch in 2031 – will study the atmospheres of known planets outside our solar system using infrared light.
• M5 – EnVision, will launch in 2031 – will map the planet Venus from orbit.
• S1 – CHEOPS, launched in December 2019 and still working – studies planets outside our solar system that we already know about.
• S2 – SMILE, will launch in 2026 – a joint mission between ESA and CAS to study how Earth's magnetic field interacts with the Sun's wind.
• F1 – Comet Interceptor, will launch in 2029
• F2 – ARRAKIHS, will launch in the early 2030s – will survey one hundred nearby galaxies and their area to learn about small galaxies and streams of stars.