I have a fear of large planets/stars like 'Canis Majoris' for example.
To give you an idea of what freaks me out here is a relative example of the size of this planet/star:
"If the Earth were to be represented by a sphere one centimeter (0.39") in diameter, the Sun would be represented as a sphere with a diameter of 109 centimeters (3½ ft.), at a distance of 117 meters. At these scales, VY Canis Majoris would have a diameter of approximately 2.3 kilometers (1.43 mi.), assuming the upper limit estimate of its radius."
Reading this makes my heart feel like it's getting squashed and hot and I feel flush from irrational fear... I've never experienced what I know as an anxiety attack but the thought of getting close to an unknown planet of this size completely does my nut!
Silly thing is I'm not remotely scared of anything else e.g. Heights, Spiders, Speed etc.