Information about STEREO-A close approach to Earth, August 2023

Positions of STEREO A and B for 19-Jan-2025 21:00 UT

This figure plots the current positions of the STEREO Ahead (red) and Behind (blue) spacecraft relative to the Sun (yellow) and Earth (green). The dotted lines show the angular displacement from the Sun. Units are in A.U.

When the two spacecraft are close to Earth, an expanded view of the region around Earth will appear on the right, in the same orientation as the Sun-centered view.

Other resources:

• STEREO Orbit Tool
• STEREO-A Fly-by Orbit Tool for Summer 2023
• STEREO-A roll angle during Fly-By
• STEREO orbit simulations
• Satellite Situation Center (SSCWeb)
• HelioWeb
• Attitude and orbit text files (CalTech)
• Early orbit summary
• Connections with Parker Solar Probe
• Explanation of coordinate systems

                                STEREO-B           Earth        STEREO-A       Parker SP   Solar Orbiter     BepiColombo

Heliocentric distance (AU)      1.008856        0.983984        0.965808        0.650622        0.915283        0.453710
Semidiameter (arcsec)            951.204         975.247         993.601        1474.939        1048.449        2115.069

HCI longitude                      5.909          43.702          72.934         238.838          25.511         183.566
HCI latitude                      -0.557          -5.027          -7.050           3.327           0.793          -3.132

Carrington longitude             150.243         188.036         217.268          23.172         169.846         327.900
Carrington rotation number      2293.583        2293.478        2293.396        2293.936        2293.528        2293.089

Heliographic (HEEQ) longitude    -37.793           0.000          29.232        -164.864         -18.190         139.864
Heliographic (HEEQ) latitude      -0.557          -5.027          -7.050           3.327           0.793          -3.132

HAE longitude                     81.697         119.698         148.833         314.618         101.008         258.908

Earth Ecliptic (HEE) longitude   -38.000           0.000          29.135        -165.079         -18.690         139.210
Earth Ecliptic (HEE) latitude      0.195          -0.000          -0.113          -2.883           3.907          -3.560

Roll from ecliptic north           0.250                           0.200
Roll from solar north              7.463                           2.323

Light travel time to Earth (min)           5.400           4.082                  13.481           2.678          11.309

Separation angle with Earth               38.001          29.135                 164.809          19.079         139.082
Separation angle A with B                         67.136

Carrington rotation 2293 runs from 2025-01-06 19:35 (DOY   6.82) to
2025-02-03 03:45 (DOY  34.16), as seen from Earth.

Last Revised: Sunday, 19-Jan-2025 21:01:18 UTC
Responsible NASA Official:
Accessibility
Privacy Policy and Important Notices
Feedback and comments: webmaster