Is the Tombaugh Regio on Pluto discernably visible from Earth ground based or Earth orbiting telescopes? And more generally, can surface features seen in Hubble images be matched with images from New Horizons? I can imagine a match from the image compilation I attach, with TR being the bright triangle, but is that intuition valid?

enter image description here

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    $\begingroup$ Wikipedia states, "The feature had been identified as a bright spot for six decades prior to the New Horizons flyby, although it was impossible to image it with enough resolution to determine its shape. Over these six decades the spot had been observed to be dimming." $\endgroup$
    – HDE 226868
    Jul 18 '15 at 18:03

Your First Question - Can it be done from the ground?

Unfortunately making maps that have this level of detail from the ground is not possible with current telescopes. There are 2 problems; first, it takes a lot of magnification to resolve Pluto and even more to resolve surface features. Second, from the ground you need more than just magnification, you need EXTREMELY stable skies or that will wash out the surface features. Getting just one super sharp image is not enough, you need several to ensure that you have high enough signal to noise to believe the surface features are real.

This is why Marc Buie, who used the High Resolution Channel on the Advanced Camera for Surveys on HST to create the image you put in your question. Unfortunately, even that level of resolution is not possible anymore as HRC is no longer functional. These kind of maps can be very hard to make.

There have been other maps of pluto, both from the ground and using HST. Here is a compilation of several using a compilation of ground based photometry, the Fine Optical Camera on HST and the ACS HRC. As you can see from the ground based photometry you can make a map, but it is very poor resolution compared to what HST can do.

Other Pluto Maps

There have been other HST press releases about those other images

Second Question - How well do the maps match?

There is a good blog post about how they match up from the museum of applied arts and sciences at the Sydney Observatory. But the bottom line is that they match up pretty well, but not perfectly. This is expected as we expected volitle transport on the surface so the surface features will change. As you can see in the image below, that there were a lot of changes from the map made in 1994 to the one made in 2003. So one would expect changes going out to 2015.

New Horizons and Hubble Images

So, yes your intuition is valid, but Pluto's surface is dynamic so it will be changing on you!


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