# Astrophotographer Thierry Legault is not convinced that DarkSat is darker than the others. Have photometric measurements been reported?

In the video below Passage of 7 Starlink satellites including (supposed) "darksat" world renowned astrophotographer Thierry Legault is not impressed by DarkSat's darkness:

SpaceX said they have coated one of the satellites (the "darksat") to make it less reflective...if ti's really the #1130 (alias Starlink U), it's not really convincing!

Thierry Legault - https://www.astrophoto.fr

Question: Have any photometric measurements of DarkSat's darkness been reported? These few-pixel images appear to be saturated so I don't think we can compare the brightness of these unresolved dots in the video.

Screen shot near the end where the objects are artificially grouped for a side-by-side comparison

• – uhoh
Jan 30 '20 at 15:01

I was able to measure STARLINK 1130 (darksat, left) on March 19th, 2020, at Sternwarte Mirasteilas. Comparison object is STARLINK 1084 (same operational height, similar altitude above the horizon, same camera gain and exposure, right).

TLE:

1 44932U 20001U   20078.91667824  .00171859  00000-0  12055-1 0  9990
2 44932  53.0013  60.9379 0001567  75.4931 267.6192 15.03912909 12250


vs

1 44915U 20001B   20078.91667824  .00153209  00000-0  10776-1 0  9998
2 44915  53.0000  60.9393 0001469  76.4760 248.6505 15.03918487 11023


It seems to be dimmer. I'll measure that out in more detail.

Best regards

rudolf

• This is great, thanks for your answer and for sharing your results! It's great when someone takes the time to share some real, hard data.
– uhoh
Mar 19 '20 at 15:13
• There was some confusion and mis-identification of StarLink-1130 (DarkSat) as described in comments here. Could you mention some internationally recognized ID for the satellite you observed, perhaps from the TLE you used to predict the orbit? Thanks!
– uhoh
Mar 19 '20 at 15:14
• I edited the answer and added the two TLEs that I used. Best regards Mar 20 '20 at 16:13