This is your monthly guide to observing the planets, celestial events, moon phases, this day in space history, NASA launches, and other astronomy resources.
Observing The Planets:
- Mercury (morning planet, magnitude -0.1) is hidden in the glare of the Sun until September 12 when it becomes visible in the early dawn.
- Venus (evening planet, magnitude -3.8) is visible low in the west at dusk all month.
- Mars (evening planet, magnitude -0.2, in Ophiuchus) is visible in the south-southwest at dusk and sets before midnight.
- Jupiter (evening planet, magnitude -1.7, in Virgo) sets in the west at dusk and begins to pass around the far side of the Sun. It will not be observable for most of the month.
- Saturn (evening planet, magnitude +0.5, in Ophiuchus) is visible in the south-southwest at dusk and sets after midnight.
- Uranus (late evening/early morning planet, magnitude +5.8, in Pisces) is visible after midnight in the southeast.
- Neptune (late evening/early morning , magnitude +7.8, in Aquarius) is visible after midnight in the southeast.
Understanding Visual Magnitude: Magnitude is a scale for measuring the brightness of objects in the sky. The dimmer the object the greater the number. The brightest objects generally receive negative numbers. Venus can be as bright as magnitude -4.9, the full moon is generally -12.7 and the sun is -26.8.
Moon Phases & Celestial Events:
- September 1: New Moon at 4:03 am CDT.
- September 1: Annular Solar Eclipse from the southern Atlantic Ocean, central Africa and Madagascar, and into the Indian Ocean.
- September 2: Neptune will be at opposition.
- September 2: Moon near Jupiter.
- September 3: Moon near Venus.
- September 6: Moon at apogee (farthest from Earth) at 2 pm CDT at a distance 405,055 km and an angular size of 29.5′.
- September 8: Moon less than 4° from Saturn.
- September 9: First Quarter Moon at 6:49 am CDT.
- September 16: Full Moon at 2:05 pm CDT.
- September 16: Penumbral lunar eclipse.
- September 18: Venus less than 2° from Spica.
- September 18: Moon at perigee (closest to Earth) at 12 pm CDT at a distance of 361,896 km and an angular size of 33′.
- September 22: Fall Equinox begins at 9:21 am CDT for the Northern Hemisphere. Spring begins in the Southern Hemisphere.
- September 23: Last Quarter Moon at 4:56 am CDT.
- September 29: Moon less than 2° from Mercury at dawn.
- September 30: New Moon at 7:11 pm CDT
The following missions are scheduled for September:
Date: September 8, 2016 – 6:05 pm CDT.
Mission: OSIRIS-REx Asteroid Sample Return Mission.
Description: NASA’s Origins Spectral Interpretation Resource Identification Security–Regolith Explorer mission (OSIRIS-REx) will reach its near-Earth asteroid target, called Bennu (formerly 1999 RQ36), in 2018. The spacecraft will collect a 2.1-ounce sample for return to Earth in 2023.
Launch Site: Cape Canaveral Air Force Station in Florida.
Targeted Date: September
Mission: Orbital ATK Resupply Mission to Space Station (Orbital CRS-5).
Description: Orbital ATK’s Cygnus cargo delivery to the International Space Station is targeted for a mid September launch.
Launch Vehicle: Antares rocket.
Launch Site:Mid-Atlantic Regional Spaceport’s Pad OA at NASA Wallops Flight Facility in Virginia.
Date: September 23, 2016 – 1:17 pm CDT
Mission: Expedition 49 Launch.
Description: NASA astronaut Shane Kimbrough and cosmonauts Andrey Borisenko and Sergey Ryzhikov of the Russian space agency Roscosmos will launch to the space station.
Launch Vehicle: Soyuz MS-02 spacecraft.
Launch Site: Baikonur Cosmodrome in Kazakhstan.
Want to learn more about what goes on each week on the International Space Station? Watch NASA’s weekly Space to Ground video log.
This Day In Space History:
- September 1, 1979: Pioneer 11, first Saturn flyby.
- September 3, 1970: NASA cancels the last two planned lunar missions.
- September 3, 1976: Viking 2 lands on Mars.
- September 5, 1977: Voyager 1 was launched.
- September 8, 1966: “Star Trek” premieres.
- September 11, 1985: ICE probe flies past Comet Giacobini-Zinner.
- September 13, 1959: Luna 2 was the first spacecraft to impact the Moon.
- September 19, 1848: William Bond discovers Hyperion, moon of Saturn.
- September 22, 2014: MAVEN spacecraft enters orbit around Mars.
- September 23, 1783: Carolyn Herschel discovers the Sculptor Galaxy (NGC 253)
- September 23, 1846: Neptune was discovered by Urbain Le Verrier and Johann Galle.
- Satellite flybys: Want to know when satellites, the International Space Station, and the Hubble Space Telescope will fly over your location? Enter your zip code here to get a personal calendar.
- Our Current Solar System: Find out the current distances and locations of the solar system planets from the Earth and sun right now.
- The Stargazer’s Guide to the Night Sky
- Sighting the International Space Station (ISS)
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