Watch Mars and Moon's conjunction on September 16-17

Late on Friday night into Saturday morning, September 16 to 17, Mars and the waning gibbous moon will be making a close approach in the night sky. The pair will rise above the east-northeastern horizon about an hour before midnight on Friday night, with the Red Planet about 4 degrees to the right of the Moon.

On Tuesday morning, September 20, the bright star Pollux will appear about 3 degrees to the upper left of the waning crescent moon. The Moon will rise above the northeastern horizon early in the morning at 1:19 a.m. EDT and morning twilight will begin less than 5 hours later at 5:56 a.m.

On early Friday morning, September 23, Mercury will pass between Earth and the Sun, a phenomenon called inferior conjunction. According to NASA, planets that orbit inside of the orbit of Earth can have two types of conjunctions with the Sun - inferior (when passing between Earth and the Sun) and superior (when passing on the far side of the Sun from Earth). In addition, Mercury will shift from the evening sky to the morning sky and will begin emerging from the glow of the dawn on the eastern horizon after September 27.

Also Friday morning, Regulus, the brightest object in the constellation Leo and one of the brightest stars in the night sky, will appear about 5 degrees to the right of the Moon. The pair will rise above the east-northeastern horizon at about 4:27 a.m. EDT around 1.5 hours before morning twilight begins at 5:59 a.m., according to NASA.

Further, on September 26, Jupiter will be at its closest and brightest for the year, an event known as opposition, because it will be opposite Earth from the Sun, effectively a full Jupiter. The solar system's largest planet will rise around sunset and set around sunset. Planets that orbit farther from the Sun than Earth can be seen at opposition from Earth.