The Silver Y moth, with a silver (off-white) letter "Y" mark on each forewing is a common summer migrant which flies by day and by night.
Side view showing raised tussocks
and from the back.
Wingspan 35-40mm; UK migrant May-Oct. Some colour variation, especially warmer chestnut and cooler grey-brown.
It is native to most of Eurasia and North Africa, - resident in the warmer south and summer migrant in the cooler north.