blue arcs

arcs, blue 

Entoptic phenomenon appearing as two bands of blue light arching from above and below the source towards the blind spot. This phenomenon is induced by a small source of light (preferably red) stimulating the temporal side of the retina near the fovea. See entoptic image.
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Caption: Ripples of hot gas (blue arcs), detected In X-ray data, race away from an erupting supermassive black hole In the center of galaxy NGC 5195.
The electric blue arcs making up the spectacular egg-like shape framing these objects are a result of the galaxy cluster's immense gravity.
If you look at the right edge of a small red light in an otherwise dark field with a partly dark-adapted right eye, you will momentarily see faint blue arcs curving away from the light toward the right (see Figure 10).
You can easily see the blue arcs at night in your home in a room with some red LED indicator lights on equipment.
Purkinje first noticed entoptic sensations of blue arcs in 1825.
It was only when the arrangement of the optic nerve and retinal nerve fibres was described by Wallace in 1836 that Muller was in 1855 able to fit this anatomical relationship together with the blue arc sensations.
GRASP solution -- largest planar subgraph found in iteration: 1 size of largest planar subgraph: 20 avg size of planar subgraph: 19.2 blue arcs in planar subgraph: 16 red arcs in planar subgraph: 4 vrtx permut: 4 5 6 7 vrtx permut: 2 1 9 8 blue arcs: 1 2 3 5 7 blue arcs: 11 12 13 14 15 blue arcs: 16 17 18 19 21 blue arcs: 22 red arcs: 6 8 9 20 5.
By hypothesis, y [not equal to] t, so P contains no blue arcs. (There are no arcs into t, and so t [not an element of] P.) Therefore, P is also a path in G, contradicting that z = idom(x).
If P contains no blue arcs, then it is a path in the original graph, contradicting the claim that z = idom(x).
The original version of the map, which was released three years ago, shows most of the world illuminated by transcontinental friendships, with oceans dominated by blue arcs of light, metro.co.uk reports.
Red Bermudas, 1978-80, is on the plus side of this practice: its set of thin, curving blue arcs corresponds interestingly to the sequence of delicate step-back moldings that the arcs pass over.
In Red Bermudas, for example, he brushes blue arcs over a layer of contrasting orange; he also juxtaposes these arcs with repetitive patterns of large dots of yellow-green and orange-brown.