swap_horiz Uhuru 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

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

3

Parker Solar Probe

The Parker Solar Probe is a NASA observatory spacecraft investigating the Sun’s outer atmosphere, the corona. Launched i...

Solar Nasa Space Based Heliophysics

9.6 Brilliant

4

Galileo spacecraft

The Galileo spacecraft was a NASA observatory designed for planetary exploration of Jupiter and its moons. Launched in 1...

Decommissioned Nasa Planetary Jupiter

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

Fermi Gamma-ray Space Telescope

The Fermi Gamma-ray Space Telescope is a NASA observatory orbiting Earth. It detects high-energy gamma rays, providing i...

Survey High Energy Nasa Space Based

9.1 Excellent

8

Solar Dynamics Observatory

The Solar Dynamics Observatory (SDO) is a space-based observatory operated by NASA. It provides continuous ultraviolet i...

Solar Nasa Space Based Heliophysics

9.1 Excellent

9

Neil Gehrels Swift Observatory

The Neil Gehrels Swift Observatory is a NASA spacecraft dedicated to studying high-energy astrophysical events. Launched...

Nasa Space Based Gamma Ray X Ray

9.0 Excellent

10

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

11

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

12

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

13

eROSITA

eROSITA is a German observatory utilizing a space-based x-ray telescope. Launched in 2019 as part of the Spektr-RG missi...

Germany Survey All Sky Space Based

8.9 Great

14

WISE

The Wide-field Infrared Survey Explorer (WISE), launched by NASA in 2009, is a space telescope that completed an astrono...

Survey All Sky Nasa Infrared

8.8 Great

15

Einstein Observatory

The Einstein Observatory was a NASA X-ray telescope launched in 1978 that became the first imaging X-ray telescope to be...

Historical Nasa Space Based X Ray

8.5 Great

16

XRISM

XRISM is a JAXA and NASA X-ray astronomy satellite launched in 2023, designed to measure extreme high-energy phenomena u...

Nasa Space Based Spectroscopy X Ray

8.5 Great

17

RXTE

The Rossi X-ray Timing Explorer was a NASA satellite launched in 1995 to observe variability in X-ray emissions from bla...

Decommissioned Nasa Space Based Timing

8.4 Great

18

ASCA

ASCA was a Japanese X-ray satellite launched in 1993, featuring the first use of CCDs for X-ray imaging to study the spe...

Historical Space Based Spectroscopy X Ray

8.2 Great

19

IXPE

The Imaging X-ray Polarimetry Explorer is a NASA astrophysics satellite launched in 2021, notable for being the first de...

Nasa Space Based X Ray Esa

8.2 Great

20

EXOSAT

EXOSAT was a European Space Agency X-ray satellite launched in 1983 that operated for three years, studying galactic and...

Decommissioned Historical Space Based X Ray

7.6 Good