swap_horiz Cheops Alternatives

1

Voyager 2

Voyager 2 is a NASA-built spacecraft deployed in 1977. It’s notable for being the first to explore Uranus and Neptune pr...

Active Nasa Interstellar Outer Planets

10.0 Brilliant

2

Voyager 1

Voyager 1 is an active NASA spacecraft launched in 1977. It undertook a flyby mission to Jupiter and Saturn. The probe a...

Active Nasa Interstellar Outer Planets

9.9 Brilliant

3

Cosmic Background Explorer

The Cosmic Background Explorer (COBE) was a NASA space mission launched in 1989 to study the cosmic microwave background...

Survey Cosmology Nasa Microwave

9.4 Excellent

4

New Horizons

The New Horizons mission is an active NASA space probe studying the outer solar system. Launched in 2006, it achieved a...

Active Nasa Kuiper Belt Pluto

9.4 Excellent

5

Herschel

The Herschel Space Observatory was a European Space Agency mission launched in 2009. It operated primarily in infrared w...

Astronomy Telescope Infrared Past

8.8 Great

6

Infrared Astronomical Satellite

The Infrared Astronomical Satellite (IRAS) was a joint space telescope mission developed by the United States, the Nethe...

Telescope Nasa Infrared Past

8.6 Great

7

Solar Orbiter

Solar Orbiter is a spacecraft developed by the European Space Agency with NASA participation to study the Sun and the in...

Solar Active Nasa Orbiter

8.6 Great

8

Sentinel-2A

Sentinel-2A is an Earth-observation satellite developed for the European Union's Copernicus program and operated by the...

Imaging Active Earth Esa

8.6 Great

9

Mars Express

Mars Express is a planetary exploration mission developed by the European Space Agency (ESA), launched in 2003 to study...

Active Planetary Mars Orbiter

8.4 Great

10

Spektr-RG

Spektr-RG is a Russian-German space-based X-ray observatory launched in 2019 and placed in an orbit around the Sun-Earth...

Astronomy Russia Telescope Active

8.2 Great

11

Sentinel-3A

Sentinel-3A is an Earth-observation satellite operated as part of the European Union's Copernicus program, with the Euro...

Ocean Active Earth Esa

8.1 Great

12

Sentinel-5P

Sentinel-5 Precursor (Sentinel-5P) is an environmental satellite operated by the European Space Agency (ESA) as part of...

Active Atmosphere Earth Esa

8.0 Great

13

Infrared Space Observatory

The Infrared Space Observatory (ISO) was a European Space Agency space telescope launched by an Ariane 4 rocket in Novem...

Astronomy Telescope Infrared Past

7.9 Good

14

Akari

Akari, originally known as ASTRO-F, was an infrared astronomy satellite developed by the Japan Aerospace Exploration Age...

Survey Telescope Infrared Past

7.7 Good

15

ExoMars Trace Gas Orbiter

ExoMars Trace Gas Orbiter is a collaborative Mars mission launched in 2016 by the European Space Agency (ESA) and Roscos...

Active Mars Orbiter Esa

7.7 Good

16

AstroSat

AstroSat is an Indian space observatory designed to study astronomical sources across ultraviolet and X-ray wavelengths....

Astronomy Telescope Active Multiwavelength

7.4 Good

17

EarthCARE

EarthCARE, short for Earth Cloud, Aerosol and Radiation Explorer, is a joint Earth-observation mission developed by the...

Active Earth Esa Jaxa

7.2 Good

18

BepiColombo

BepiColombo is a joint European Space Agency and Japan Aerospace Exploration Agency mission to study Mercury. Launched o...

Active Mercury Orbiter Esa

7.1 Good

19

Biomass

Biomass is an ESA Earth Explorer satellite mission launched on 29 April 2025 aboard a Vega-C rocket from French Guiana....

Active Radar Forest Earth

6.9 Fair

20

Hera

Hera is a European Space Agency space-safety mission to the binary asteroid system Didymos and Dimorphos. Launched on 7...

Active Binary Asteroid Esa

6.8 Fair