On July 5, just a night after the sky is filled with fireworks of Independence Day celebrations, there will be another reason for people to look up at the stars.
People that look in the southwest direction of the sky once dusk falls will see the half-lit moon accompanied very closely by a bright, yellow-orange spot, which would be the fourth planet in our solar system, Mars.
While Mars is twice the size of the moon, it will only appear as a small spot because it is 400 times farther from the Earth than the moon.
The moon will be a waxing gibbous moon, which will have 58 percent of its surface illuminated and will be just past its first quarter phase.
Near the pair of the moon and Mars is another brightly shining star, and that would be Spica in Virgo, which is a white-hot star that is a massive 1,500 times the size of Mars at a much longer distance of 16 million times farther away.
When people look up at the sky, they will see the moon coming at its closest point to Mars at dusk. The moon's placement in the sky will continue to move in relation to Mars and Spica, until the three celestial bodies find their places after midnight.
A much more interesting sight can be seen happening as people in Panama and most of South America will see the moon move across the sky right over Mars. The dark edge of the moon will slowly move to the orange dot that is Mars, covering it entirely over a span of about half of a minute. The moon will pass over Mars about an hour later, with the orange spot appearing from behind the other side of the moon.
This astronomical phenomenon is known as occultation, which stems from the Latin word for "hide."
Occultation by the moon of a planet does not happen as often as the occultation by the moon of stars. When stars are involved, they don't fade slowly over the edges of the moon, but rather instantly disappear due to their great distance.
The great distance of stars has made astronomers utilize them as very accurate reference points in the sky. In the past, they have been used as timekeeping and distance indicators. However, recent advancements in technology, such as GPS, have made star-based processes obsolete.
