Solar Terrestrial Relations Observatory (STEREO)

The NASA Solar TErrestrial RElations Observatory (STEREO) mission consists of two identical spacecraft which were placed in two different orbits around the Sun. STEREO Ahead was placed slightly closer to the Sun than Earth and STEREO Behind slightly further away than Earth. This causes them to respectively pull farther ahead of and fall gradually behind Earth's orbit and thus exposing the farside of the Sun. On the site you will find data from the SECCHI instrument: the extreme ultraviolet imager (EUVI) camera showing the Sun in the 195 Ångström wavelength and two white-light coronagraphs: COR1 and COR2.

Communications with STEREO Behind were lost on October 1, 2014, due to multiple hardware anomalies affecting control of the spacecraft orientation. There is currently no real-time data available from STEREO Behind. Should communications be reestablished in the future we will feature any data coming from STEREO Behind on this page.

Where are STEREO A and B right now?

Where are STEREO A and B right now?

Info
Courtesy of STEREO (NASA)

Latest news

Support SpaceWeatherLive.com!

A lot of people come to SpaceWeatherLive to follow the Solar activity or if there is a chance to see the aurora, but with more traffic comes higher costs to keep the servers online. If you like SpaceWeatherLive and want to support the project you can choose a subscription for an ad-free site or consider a donation. With your help we can keep SpaceWeatherLive online!

No Ads on SWL Pro!
No Ads on SWL Pro! Subscriptions
Donations
Support SpaceWeatherLive.com! Donate
Support SpaceWeatherLive with our merchandise
Check out our merchandise

Latest alerts

Get instant alerts!

Space weather facts

Last X-flare2026/04/24X2.5
Last M-flare2026/04/28M1.11
Last geomagnetic storm2026/04/20Kp5 (G1)
Spotless days
Last 365 days3 days
20263 days (2%)
Last spotless day2026/02/24
Monthly mean Sunspot Number
April 202679.3 -6.6
May 2026145.5 +66.2
Last 30 days91 -4.3

This day in history*

Solar flares
12024X1.6
22022X1.1
32013M8.19
42023M7.2
51999M6.41
DstG
11967-123G3
21978-114G3
31976-107G4
41994-79G2
51977-77G1
*since 1994

Aurora on this day in history

No observations submitted for this day in history. If you've observed the aurora and you have some amazing photos to show off, submit your observations now!
Submit your aurora observation

Social networks