Encounter 6 Summary

Encounter 6 (2020-09-19 - 2020-10-13, with limited additional data 2020-08-08 - 2020-10-31)


This animation shows all WISPR full-field observations from the sixth PSP Mission Encounter (2020-09-21 - 2020-10-22), processed via the LW Algorithm developed by Dr. Guillermo Stenborg (JHUAPL) and detailed in Appendix A of Howard et al. 2022 (ApJ, 936, id.43. DOI 10.3847/1538-4357/ac7ff5). We have superimposed a grid showing helioprojective longitude and latitude, and a scale representation of the size and location of the Sun in the observations using the SDO/HMI Carrington map for this time period. The velocity and distance metrics displayed on the movies correspond respectively to the spacecraft's heliocentric velocity in kilometers per second, and its distance from the Sun's center in units of solar radii (where 1 solar radius = 695,700km). The "FOV Range" label provides the plane-of-sky distance limits of the inner and outermost edges of the fields of view, in units of solar radii. The horizontal blue line indicates the orbital plane of PSP. The timespan of this composite movie covers only the nominal science window when the spacecraft was within 0.25 au; a limited amount of data outside of this range may be available at the below links.
You can also download this movie directly as a 175MB mp4 file. It is also available in the same format using the L3 images, which can be downloaded here as a 42MB mp4 file.

[Credit: NASA/NRL/JHUAPL. Movie processed/compiled by Guillermo Stenborg (JHUAPL) and Brendan Gallagher (NRL). SDO inset courtesy of NASA/SDO and the AIA, EVE, and HMI science teams.]


Solar Features

2020-09-26 08:07 Streamer Blob
2020-09-27 00:39 Streamer Blob
2020-09-28 00:06 Streamer Blob
2020-09-29 03:17 Streamer Blob
2020-09-29 10:45 Streamer Blob
2020-10-01 10:16 Streamer Blob

Comets and planets

The following comets were observed during this encounter. Note that some of the data sets occur outside the nominal Encounter window and, in many cases, the spacecraft may have a non-standard roll orientation. Thus only limited observations would have been made for the comet in question. If you have trouble locating the comets in any of these data or questions regarding the proper treatment of the comet observation data, please contact the WISPR comet observation coordinator, Karl Battams - karl.battams[at]nrl.navy.mil.

The following planets can be seen in the nominal encounter sequence movie (above), moving from left to right:

  • TBD

Operations summary

  • TBD

Miscellaneous notes

Upon analysis of our Encounter 6 observations, we noted an anomalous, excess global brightness in the images from both telescopes in the time period between the beginning of September 26th until around noon on the 27th. The source of this anomalous brightening could not be identified yet (i.e., whether K-corona or dust related, instrumental, etc.). As a result, the processed L3 observations for this time period do not look as “clean” as for previous encounters, in particular for the inner camera.

Moreover, in order to collect more photons per exposure, a different gain setting was exercised in the images of the inner telescope during a few days around perihelion, which causes the signal to noise ratio of the images to be different between the sets obtained with different gain settings. This also affected the quality of the background scene in the processed L3 observations.

Thus, for this encounter and for the Inner camera only, we are providing, in addition to the standard L3 products (i.e., fits files, Level-3 PNGs, MVI, and MPG files), a new Level-3 data variant. The standard L3 version consists basically of the difference between the L2 data products and their respective L2b backgrounds, corrected by the instrumental artifacts. The new L3 "ratio" variant accounts for the background removal instead by considering the ratio between the L2 and L2b data products, also corrected by the instrumental artifacts. The L3 “ratio” variant performs better at displaying the K-corona variability and background scene, hence their release.

We are continuing to evaluate these observations to identify the source behind the excess brightness, and will provide updates as we have them.

Encounter 6 Data Products

Released data for all encounters can be obtained from our WISPR Data Page. Descriptions of other encounters can be found on the Encounter Summaries Page.