Four new mission proposals are being considered by NASA. After a nine-month concept study is completed, two of the proposals will be chosen to be built.

Studying the sky in the ultraviolet range is one of the topics covered by the four mission concepts.

This image from NASA’s Hubble Space Telescope features the spiral galaxy Mrk (Markarian) 1337, which is roughly 120 million light-years away from Earth in the constellation Virgo.
This image from NASA’s Hubble Space Telescope features the spiral galaxy Mrk (Markarian) 1337, which is roughly 120 million light-years away from Earth in the constellation Virgo. ESA/Hubble & NASA, A. Riess et al.

The Medium Explorer section and the Missions of Opportunity section are where the concepts are located.

The Explorers Program has a proud tradition of supporting innovative approaches to exceptional science, and these selections hold that same promise. These proposals are inspiring in their scope and creativity to explore the unknown in our universe

It is important to understand astronomy from smaller objects like planets and moons all the way up to entire galaxies and how they interact in order to get the most out of it. Projects in topics like heliophysics and astrophysics are funded by the explorer's program.

The NuSTAR X-ray telescope was the first to spot a comet, and the Transiting Exoplanet Survey Satellite was the first to find a planet outside our solar system. The upcoming SPHEREx mission will survey the entire sky to investigate the origin of the universe.

The Mission of Opportunity missions have a total budget of $80 million, while the recently selected missions under the Medium Explorer program have a total budget of $300 million.

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