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

Positions of STEREO A and B for 27-Jul-2024 00:00 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)      1.082192        1.015536        0.955601        0.656481        0.903752        0.564378
Semidiameter (arcsec)            886.744         944.947        1004.213        1461.776        1061.826        1700.329

HCI longitude                    206.378         228.135         248.751         240.529          27.789         195.208
HCI latitude                       3.063           5.416           6.882           3.385           0.476          -2.045

Carrington longitude             339.577           1.334          21.951          13.729         160.988         328.408
Carrington rotation number      2287.057        2286.996        2286.939        2286.962        2286.553        2287.088

Heliographic (HEEQ) longitude    -21.757           0.000          20.617          12.395         159.654         -32.927
Heliographic (HEEQ) latitude       3.063           5.416           6.882           3.385           0.476          -2.045

HAE longitude                    282.308         304.129         324.677         316.309         103.312         270.608

Earth Ecliptic (HEE) longitude   -21.822          -0.000          20.548          12.180         159.183         -33.521
Earth Ecliptic (HEE) latitude     -0.174           0.000           0.117          -2.933           3.849          -3.931

Roll from ecliptic north          -0.434                          -0.309
Roll from solar north             -6.928                          -2.931

Light travel time to Earth (min)           3.347           2.965                   3.334          15.693           5.237

Separation angle with Earth               21.822          20.548                  12.523         158.845          33.724
Separation angle A with B                         42.371

Carrington rotation 2286 runs from 2024-06-29 21:30 (DOY 181.90) to
2024-07-27 02:25 (DOY 209.10), as seen from Earth.

Last Revised: Saturday, 27-Jul-2024 00:01:05 UTC
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