Unusually large orange full moon greets Earthlings. Why was the moon orange?

Why is the moon orange tonight? Millions of people across the world were surprised to see the colour of the full moon that rose in the sky this week. This was because of the position of the Moon as part of a phenomenon that happens after 18.6 years. The Moon illusion made the lunar body appear unusually large as it sat at the horizon. July's full moon hung extremely low and was exactly opposite to the Sun. It mirrored the Sun's position. The Sun reached its highest point in the sky for the year during the summer solstice. So while the Sun was at its highest point, the Moon was at its lowest point. The sun's gravity dragged the moon's tilted orbit into its most extreme inclination relative to Earth's celestial equator. Because of being so close to the horizon, the Moon travelled from southeast to southwest without ever rising higher than about 20 degrees in altitude. Also Read: July Full Moon: An optical illusion will make the moon appear abnormally large. Here's why

Why was the Moon orange tonight?

There is also a major lunar standstill going on. At this point, the Moon rises at its most extreme northern point in the sky and sets in the greatest southern position. Its position wouldn't change much in the coming months, which is why it is said to be at a "standstill." This occurrence in the life cycle of the Moon is also the reason for its bright yellow or orange appearance. Earth's atmosphere scatters its light in a different way at this position. When at this point on the horizon, the Moon's light travels through more of our atmosphere. The blue light scatters, and the longer wavelengths, like red and orange, pass through. This gives Moon the appearance of an orange, yellow or rusty red body. Also Read: July Full Moon 2025: When and where to watch the 'Buck Moon' today — Why it's special

The Moon also appeared extremely large, but that was also simply because of its position. NASA explains that each time the Moon is close to this horizon, it appears bigger. This is only an illusion. "When we observe the Moon near the horizon, it often looks HUGE – whether it's peeking over the shoulder of a distant mountain, rising out of the sea, hovering behind a cityscape, or looming over a thicket of trees," NASA wrote in a blog post. "But here's the thing: it's all in your head. Really. The Moon's seeming bigness is an actual illusion, rather than an effect of our atmosphere or some other physics," it added.

July's full moon is also known as Buck Moon because this is the time of the year when male deer grow its full antlers. The velvet antler growth, called antlerogenesis, reaches its peak and becomes more prominent. It is also called Thunder Moon as some parts of the US witness summer thunderstorms in July.