If the apparent visual magnitude of the Sun is -26.5 and that of the full moon is -12.5, what is the light intensity ratio of sunlight to moonlight received at Earth on the day of the full moon?
Symptoms of a cold sore can include: 1  a tingling sensation, redness and swelling around the lip before the cold sore develops. 2  small, fluid-filled blisters which break open and develop a yellow crust (scab). The scab usually falls off around seven days later.
The border of the lip is the most common place that these sores appear. They may occasionally occur inside the mouth, too. This is more likely in people who have weakened immune systems or other medical problems. The first sign of a cold sore is a tingling, burning or itching.