swap_horiz Planck Alternatives

1

Cassini-Huygens

The Cassini-Huygens mission, operated by NASA and ESA, was a space-based observatory dedicated to studying Saturn and it...

Decommissioned Nasa Planetary Space Based

9.8 Brilliant

2

Gaia

The Gaia observatory is a space-based mission operated by the European Space Agency. It meticulously surveys our galaxy,...

Survey Optical Space Based Astrometry

9.7 Brilliant

3

Kepler Space Telescope

The Kepler Space Telescope was a NASA observatory launched in 2009. It monitored over 150,000 stars for dips in brightne...

Decommissioned Optical Nasa Space Based

9.6 Brilliant

4

Hipparcos

Hipparcos was a European Space Agency observatory launched in 1989. It performed groundbreaking measurements of stellar...

Parallax Decommissioned Space Based Astrometry

9.4 Excellent

5

SOHO

SOHO is a space-based observatory operated jointly by NASA and the European Space Agency. It monitors the Sun’s activity...

Solar Nasa Space Based Esa

9.3 Excellent

6

Spitzer Space Telescope

The Spitzer Space Telescope was a NASA space-based observatory operating from 2003 to 2020. It utilized infrared light t...

Survey Decommissioned Nasa Infrared

9.2 Excellent

7

Planck Observatory

The Planck Observatory was a European Space Agency satellite launched in 2009. It meticulously measured microwave radiat...

Space Historical Microwave Cmb

9.2 Excellent

8

Herschel Space Observatory

The Herschel Space Observatory is a decommissioned space-based observatory operated by the European Space Agency (ESA)....

Decommissioned Infrared Space Based Esa

9.1 Excellent

9

XMM-Newton

The XMM-Newton observatory, operated by ESA, observes the universe primarily in X-rays. Its large telescope allows for d...

High Energy Space Based X Ray Photometry

8.9 Great

10

Compton Gamma Ray Observatory

The Compton Gamma Ray Observatory was a NASA space-based observatory that operated from 1991 until its decommissioning i...

Decommissioned High Energy Nasa Space Based

8.9 Great

11

BeppoSAX

BeppoSAX was a European Space Agency observatory launched in 1996. This satellite primarily observed X-rays and gamma ra...

Historical Space Based X Ray Gamma Ray Bursts

8.9 Great

12

South Pole Telescope

The South Pole Telescope is a 10-meter diameter microwave and millimeter-wave observatory located at the Amundsen-Scott...

Cosmology Microwave Antarctica Cmb

8.7 Great

13

ROSAT

ROSAT, short for Röntgensatellit, was a German-led space observatory launched in 1990 for X-ray and extreme-ultraviolet...

Germany Decommissioned All Sky Space Based

8.6 Great

14

Atacama Cosmology Telescope

The Atacama Cosmology Telescope (ACT) was a 6-meter survey telescope located at an elevation of 5,190 meters on Cerro To...

Cosmology Microwave Chile Cmb

8.5 Great

15

Hinode

Hinode, which translates to "sunrise" in Japanese, is a solar observation satellite developed by the Japan Aerospace Exp...

Solar Space Based X Ray Esa

8.4 Great

16

RXTE

The Rossi X-ray Timing Explorer (RXTE) was a NASA satellite launched on December 30, 1995, to study time variability in...

Decommissioned Nasa Space Based Timing

8.4 Great

17

LISA Pathfinder

LISA Pathfinder was an European Space Agency technology demonstrator spacecraft launched on December 3, 2015. Its primar...

Decommissioned Space Based Gravitational Wave Esa

8.4 Great

18

Simons Observatory

The Simons Observatory is a cosmological survey facility located at an elevation of 5,200 meters on Cerro Toco in Chile'...

Cosmology Microwave Chile Cmb

8.3 Great

19

IXPE

The Imaging X-ray Polarimetry Explorer (IXPE) is a NASA space observatory launched on December 9, 2021, designed to meas...

Nasa Space Based X Ray Esa

8.2 Great

20

EXOSAT

EXOSAT was a European Space Agency space observatory launched in 1983 to study X-ray sources beyond Earth. Operating unt...

Decommissioned Historical Space Based X Ray

7.6 Good