About

UVEX is a new NASA Medium Explorer mission to explore the ultraviolet sky, with an expected launch date in 2030. With a wide-field, two-band imager and long, multi-width slit spectrometer, UVEX is equipped to address key scientific themes identified in Pathways to Discovery in Astronomy & Astrophysics for the 2020s (Astro2020).

UVEX Capabilities

With simultaneous FUV and NUV imaging over a 12 deg² field of view and a PSF of ~2 arcseconds, UVEX will perform a modern synoptic all-sky survey, reaching depths of >25 AB mag over two years.

A 2-degree-long spectroscopic slit with multiple widths will obtain sensitive, R>1000 spectra across a broad UV bandpass that includes many important diagnostic lines, efficiently probing dense stellar regions and resolved galaxies, and obtaining a wealth of serendipitous spectra.

UVEX will be able to rapidly respond to targets of opportunity, providing photometric or spectroscopic follow-up within ~3 hours of a trigger, probing the bright, fast UV emission of neutron star mergers and cosmic explosions.

UVEX Mission Parameters

Science Mission	Launch: 2028, duration 2 years
Imaging FOV	3.5° x 3.5°
Image Quality (HPD)	< 2.25″
Imaging Bandpass	FUV: 1390–1900 Å NUV: 2030–2700 Å
Sky Survey Depth	> 25.8 mag (FUV and NUV)
Spectrograph	2°-long slit, multiple widths
Spectrograph Bandpass	1150–2650 Å
Spectrograph Resolution	R > 1000
Orbit	Elliptical 17 R_E x 59 R_E, 13.7 days
Instantaneous Sky Accessibility	> 70%
Average ToO Response	< 3 hours

Why UVEX?

With the end of the GALEX mission in 2013, and the ageing of the Hubble Space Telescope and the Neil Gehrels Swift Observatory, it is time for a new, broad-capability ultraviolet mission. UVEX will provide a generational improvement over the GALEX sky survey and is equipped to respond to the rapidly-changing dynamic ultraviolet universe.

The coming decade will see modern synoptic and deep wide-area sky surveys with the Vera C Rubin Observatory, the Nancy Grace Roman Space Telescope, and ESA’s Euclid space telescope. UVEX provides the crucial complementary UV data required to create a modern, multi-wavelength map of our Universe.