Ring in the month and get ready for winter. The September equinox occurs when the sun crosses the celestial equator (an imaginary line in the sky above earth’s equator — from north to south). This year it will occur on September 23, 2017. The sun will shine directly on the equator and the length of day and night will be nearly equal. Also known as the Autumnal equinox, it will be considered as the first day of Fall and will officially be the end of summer in the Northern hemisphere. Watch out for the constellation of Aquarius — the Water Bearer, which is a summer constellation, and is best viewed in the night sky in September.
Planets to look out for
Mercury will appear in the western sky and will set about an hour after sunset. As a morning star, it will appear in the eastern sky, rising about an hour before the sun. Look out for a bright star with a yellowish hue. See it in the mornings from September 6 to September 20. Mars, a shining star with a yellow-orange hue, will be mostly seen in the mornings from September 11 through December. While Uranus will be visible in the mornings catch Neptune shimmer in the night sky. Remember that all planets look like stars with the naked eye. These include Mercury, Venus, Mars, Jupiter and Saturn. Uranus and Neptune are visible as tiny discs when viewed through a telescope.
Mark the dates
September 5: Watch out for the blue planet — Neptune, as it will be the closest to earth and its face will be fully illuminated by the sun. It will be brighter and visible all night long. Because of its distance from earth, it will appear as a tiny blue dot in all but the most powerful telescopes.
September 6: The night sky will be at its brightest as the full moon will be located on the opposite side of the earth. This full moon used to be known as the Full Corn Moon by Native American tribes because they harvested their crop around this time.
September 12: Watch out for Mercury’s Greatest Western Elongation. This is the best time to view the planet as it will be at its highest point above the horizon in the morning sky. Look for the planet in the eastern sky just before sunrise.
September 20: Welcome the new moon. The moon will be located on the same side of the earth and hence will not be visible in the night sky. This is the best time of the month to observe faint objects such as galaxies and star clusters because there is no moonlight.