This is the Saint Louis Science Center’s NIGHT SKY UPDATE for the week of Tuesday, May 29. All times are given as local St. Louis time (Central Daylight Time). For definitions of terminology used in the night sky update, click the highlighted text.

Information updated weekly or as needed.

Join us for our next star party, Friday, June 1, 2018 held in association with the St. Louis Astronomical Society. For details, see the information at the bottom of this page.

The Sun and the Moon
Sunrise is at 5:40 a.m. on Tuesday, May 29 and sunset is at 8:18 p.m. providing us with about 14.5 hours of daylight. Even after sunset, the light from the sun will still dimly illuminate our sky for nearly 2 hours. This period of time is called twilight, which ends around 22:11 p.m. this week. For those with a sun dial, solar transit or local noon occurs around 12:58 p.m. this week.

Day

Sunrise

Sunset

29 May

5:40 a.m.

8:18 p.m.

30 May

5:39 a.m.

8:18 p.m.

31 May

5:39 a.m.

8:19 p.m.

01 Jun

5:38 a.m.

8:20 p.m.

02 Jun

5:38 a.m.

8:20 p.m.

03 Jun

5:38 a.m.

8:21 p.m.

04 Jun

5:37 a.m.

8:22 p.m.

05 Jun

5:37 a.m.

8:22 p.m.

06 Jun

5:37 a.m.

8:23 p.m.

Moonrise for Tuesday, May 29 occurs at 8:25 p.m. and moonset will occur at 6:38 a.m. on the following day. On Tuesday, May 29 the moon will be exhibiting a full phase. May’s full moon is often called the Full Flower Moon. occurs on May 29.

International Space Station (ISS) Observing
Visible passes of ISS from St. Louis for the week of May 29 occur in the evening hours. The best of these occur on the evenings of June 3, 4 and 6. Use the table below for information about these and other visible passes of ISS this week.

Catch ISS flying over St. Louis starting Tuesday, May 29

Mag

Starts

Max. altitude

Ends

Time Alt. Az. Time Alt. Az. Time Alt. Az.

30 May

-0.8 00:09:15 10 NNW 00:10:17 17 NNW 00:10:17 17 NNW

30 May

-1.3 23:17:21 10 NNW 23:19:44 19 NNE 23:19:44 19 NNE

31 May

-1.0 22:25:33 10 NNW 22:27:17 14 NNE 22:29:02 10 NE

01 Jun

-0.9 00:01:03 10 NW 00:01:51 16 NW 00:01:51 16 NW

01 Jun

-2.0 23:08:59 10 NW 23:11:21 30 N 23:11:21 30 N

02 Jun

-1.7 22:17:00 10 NNW 22:19:36 21 NNE 22:20:52 17 ENE

02 Jun

-0.8 23:53:04 10 WNW 23:53:30 13 WNW 23:53:30 13 WNW

03 Jun

-1.2 21:25:06 10 NNW 21:27:07 15 NNE 21:29:07 10 ENE

03 Jun

-2.6 23:00:46 10 NW 23:03:03 42 NW 23:03:03 42 NW

04 Jun

-2.9 22:08:36 10 NW 22:11:44 41 NE 22:12:38 32 ENE

05 Jun

-2.0 21:16:33 10 NNW 21:19:19 25 NNE 21:22:05 10 E

05 Jun

-2.3 22:52:48 10 WNW 22:54:53 29 W 22:54:53 29 W

06 Jun

-3.9 22:00:22 10 NW 22:03:39 80 SW 22:04:32 44 SE

Magnitude (Mag): The Measure of brightness for a celestial object. The lower the value is, the brighter the object will be.

Altitude (Alt): The angle of a celestial object measured upwards from the observer’s horizon.

Azimuth (Az): The direction of a celestial object, measured clockwise from an observer’s location with north being 0°, east being 90°, south being 180° and west being 270°.

For information about ISS flyovers and other visible satellites, visit www.heavens-above.com

Detailed information regarding all unmanned exploration of our universe, missions past, present, and planned, can be found at Jet Propulsion Laboratories: http://www.jpl.nasa.gov/

The Planets Visible Without a Telescope

This week we only four of the naked eye planets remain visible. Venus remains a brilliant object in the west after sunset, Jupiter is visible after sunset, Saturn is best after midnight and Mars is still an early morning target.

Venus

The second planet from the sun is climbing out of the sun’s glare. Typically the 30 minute mark after sunset is what we use to determine if a planet is visible yet. Using this approach Venus will be about 21° above the western horizon around 8:50 p.m. Those with a clear western horizon should be able to see Venus soon after sunset low in the west.

The evening apparition of Venus that is starting will last all the way through October 2018. So for most of the year Venus will be an early evening target. Another observing note is that Venus will start in a gibbous phase and end this apparition in a crescent phase. Planets that are closer to the sun than we are exhibit phases like the moon does. As the apparition progresses Venus will grow brighter because it will be getting closer to Earth. On October 26 Venus will reach inferior conjunction which is when Venus passes between the Earth and Sun.

Mars

The red planet has started another apparition and can be found rising in the east by 12:18 a.m. Each week Mars will rise a little earlier than the week before as we approach the 2018 Mars opposition which occurs on July 27.

If you want to start preparing for the upcoming 2018 Mars opposition follow this link: http://www.alpo-astronomy.org/jbeish/2018_MARS.htm

Jupiter

The king of the planets can rises before the sun sets. Start looking for it low in the west about 30 minutes after sunset. Jupiter will set by 4:37 a.m.

Saturn

Saturn has been slowly climbing out of the Sun’s glare for some time now however the angle of the ecliptic in the early morning has kept the ringed planet low. Saturn is now rising by 10:20 p.m. and will be an easy target by 11:30 p.m.

Our next Star Party will be held on Friday, June 1, 2018, from dusk until 10 p.m.

As part of the Saint Louis Science Center’s First Fridays, weather permitting, the St. Louis Astronomical Society and the Science Center will set up a number of telescopes outdoors and be on-hand to answer your questions. Telescope viewing begins once it is dark. Regardless of the weather on June 1, join us indoors in our planetarium theater for “The Sky Tonight”. Showtime is at 7 p.m.

This free, indoor star program will introduce you to the current night sky, the planets, and the seasonal constellations. Doors open 15 minutes before show time. Shows begin at 7 p.m. Sorry, no late admissions due to safety issues in the darkened theater.

The St. Louis Astronomical Society helps host the monthly Star Parties at the Saint Louis Science Center which are held on the first Friday of each month. Our Monthly Star Parties are open to the public and free of charge. Telescope viewing is scheduled to start around 7:00 p.m. however with the change to daylight saving time, darkness starts closer to 8:00 p.m.