Thanks for the question.

This beautiful creature is a White Lined Sphinx moth caterpillar (Hyles lineata).  More generally, it is called a hawk moth. It has a very distinguishing characteristic. Look at the end of the caterpillar on the left side of the picture. You should be able to see a yellow perturbance. This is at the posterior end of the caterpillar. The adult is quite large, almost as big as a hummingbird. It is most active at night in flower gardens fulfilling its role as an important insect pollinator. It is a very common moth in Minnesota. The color of this caterpillar can vary in color from what you observed to striking green. See the following for further information:

http://www.minnesotaseasons.com/Insects/white-lined_sphinx.html

https://apps.extension.umn.edu/garden/diagnose/insect/general-curiosity-insects/flies/large/whitelinedsphinxmoth.html

https://apps.extension.umn.edu/garden/diagnose/insect/general-curiosity-insects/immature-insects/large/whitelined-sphinx-caterpillar.html

https://bugguide.net/node/view/1625107

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