This is the Saint Louis Science Center’s NIGHT SKY UPDATE for the week of Friday, August 26, 2022.
Information updated weekly or as needed.
Times given as local St. Louis time which is Central Daylight Time (CDT). For definitions of terminology used in the night sky update, click the highlighted text. If relying on times posted in Universal Time (UT), St. louis is -5 hours when CDT.
Public Telescope Viewings
Public telescope viewings at the McDonnell Planetarium have returned as part of the Saint Louis Science Center’s First Friday event. As we ease back into our telescope nights, they will operate a little different than before. To take part in our telescope viewings you will need to get a ticket for the planetarium show that starts at 7:00 p.m. as part of the First Friday event. Tickets for the First Friday planetarium show are free, but they can only be picked up at the Saint Louis Science Center on the night of the event. After the planetarium show ends you will be able to go outside and look through telescopes weather permitting. We will update this posting if anything changes.
Solar telescopes viewings have also returned and will take place every Sunday from 11:00 a.m. to 3:00 p.m. weather permitting. Solar Sundays will run from May 29, 2022, to September 4, 2022. The return of Solar Sundays is a good opportunity to prepare for the upcoming solar eclipses in 2023 and 2024.
Observing Highlight of the Week
Phased view of Mercury from the Messenger spacecraft. Image credit: NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie
This week is a decent opportunity to spot the elusive planet Mercury. It is currently in an evening apparition which means you can look for it in the west about 20 minutes after sunset. Admittedly, this is not the best apparition due to the low angle of the ecliptic and Mercury currently appears south of the ecliptic. Unfortunately, this only provides us with a short window of time to spot the planet before it is too low. That said, there are a few events involving Mercury this week worth exploring.
First, on August 27, 2022, Mercury will reach greatest eastern elongation. After sunset, on this date, Mercury will appear roughly 6° above the western horizon about 20 minutes after sunset. Sunset on August 27 is 7:38 p.m.
On August 28 and 29, the Moon will serve as a guide to help you spot Mercury. On August 28, the Moon will appear roughly 9.5° north of Mercury. If you have binoculars at home, 9.5° will be just a little wider than most binocular views. If you can spot the thin crescent Moon this evening, pan your view a little bit south and you should spot Mercury. On August 29, the Moon and Mercury will exhibit a conjunction. This unfortunately occurs in the daytime and will not be visible from St. Louis. Even though we miss out on conjunction, the Moon and Mercury will still appear close together on August 29 after sunset. On this evening, the Moon will appear about 5° east of the Moon. This time you should be able to fit both objects in the field of view for most binoculars. Try looking for the pair about 20 minutes after sunset.
Lastly, Mercury will reach dichotomy on August 29, 2022. This is when Mercury exhibits a quarter phase. You will need a telescope to see this and sadly Mercury’s low altitude once it is dark enough to spot the planet will make viewing dichotomy difficult.
For most of us, Mercury will likely be too low to spot from our backyards. Tree lines and other buildings will prove to be problematic. If you are interested in spotting Mercury this week, I recommend finding a large parking lot with a clear western view. Grocery stores, shopping malls and other such large venues often provide views to the horizon.
The Sun and Moon
The Moon as seen from the International Space Station, on July 31, 2011.
Credit: NASA
Sunrise is at 6:25 a.m. on Friday, August 26 and sunset is at 7:40 p.m. providing us with a bit over 13 hours of daylight. Even after sunset, the light from the Sun will dimly illuminate our sky for roughly 1 hour and 30 minutes. This period is called twilight, which ends around 9:15 p.m. this week. For those with a sundial, local noon occurs around 1:02 p.m. this week.
| Day | Sunrise | Sunset |
|---|---|---|
| 2022-08-26 | 6:25 a.m. | 7:40 p.m. |
| 2022-08-27 | 6:26 a.m. | 7:38 p.m. |
| 2022-08-28 | 6:26 a.m. | 7:37 p.m. |
| 2022-08-29 | 6:27 a.m. | 7:35 p.m. |
| 2022-08-30 | 6:28 a.m. | 7:34 p.m. |
| 2022-08-31 | 6:29 a.m. | 7:32 p.m. |
| 2022-09-01 | 6:30 a.m. | 7:31 p.m. |
| 2022-09-02 | 6:31 a.m. | 7:29 p.m. |
| 2022-09-03 | 6:32 a.m. | 7:28 p.m. |
Moon
Moonrise for Friday, August 26 occurs at 5:28 a.m. and moonset occurs at 7:49 p.m. Friday, August 26, the Moon will exhibit a waning crescent phase with less than 1% of the lunar disk illuminated. New moon occurs on August 27, 2022, at 3:17 a.m.
International Space Station (ISS) Observing
Visible passes of ISS from St. Louis for the week of August 26 occur during morning hours. The best pass this week occurs on August 28. Use the table below for information about this and other visible passes this week.
Catch ISS from St. Louis starting Friday, August 26
| Date | Starts | Max. altitude | Ends | |||||||
|---|---|---|---|---|---|---|---|---|---|---|
| Time | Alt. | Az. | Time | Alt. | Az. | Time | Alt. | Az. | ||
| 28 Aug | -2.4 | 04:41:01 | 29 | NNW | 04:41:06 | 29 | NNW | 04:44:05 | 10 | NNE |
| 29 Aug | -1.2 | 03:54:37 | 21 | NNE | 03:54:37 | 21 | NNE | 03:55:56 | 10 | NE |
| Aug 30 | -1.4 | 04:41:05 | 15 | NNW | 04:41:30 | 16 | NNW | 04:43:40 | 10 | NNE |
| 31 Aug | -0.9 | 03:54:30 | 15 | NNE | 03:54:35 | 15 | NNE | 03:55:35 | 10 | NNE |
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:
The Visible Planets
Looking southeast at 10:30 p.m. August 27, 2022. Credit: Stellarium, EG
Looking southeast at 5:45 a.m. on August 20, 2022. Credit: Stellarium, EG
This week, five naked eye planets are visible. Venus will be visible in the east before sunrise. Mars rises before midnight but will still be best seen in the morning hours. Jupiter and Saturn are now evening targets. Mercury is currently in an evening apparition, but it will tough to find in the twilight glare.
Mercury
The elusive planet Mercury is briefly visible above the western horizon after sunset. About 20 minutes after sunset, you can look for Mercury about 6° above the western horizon. Tree lines will still be problematic so try and find a large parking lot with a clear view to the west.
Venus
Venus nearing the end of the current morning apparition. Venus rises at 5:12 a.m. and should be easy to spot in the southeast by 5:45 a.m. The current morning apparition lasts until the third week of October 2022. Venus reaches superior conjunction on October 22, 2022. Venus is already becoming hard to find if you have a tall tree line to the east.
Mars
Mars rises at 11:39 p.m. Start looking for the red planet around 12:30 a.m. as it clears trees and buildings. Mars is headed towards opposition later this year on December 7, 2022.
Jupiter
Jupiter rises at 9:00 p.m. and should be visible in the southeast by 10:00 p.m. As the year goes on, Jupiter will rise about 25 minutes earlier than it did the week before. Jupiter will reach opposition on September 26, 2022, so our best views of this giant world will come at the end of summer and through the fall months.
Saturn
Now past opposition, Saturn rises before the Sun sets. You can find this giant world in the southeast about 45 minutes after sunset. Saturn is still a fine target though telescopes and will be a highlight of the evening sky for the rest of the year.
James S. McDonnell Planetarium
Night Sky Update: August 26 – September 3, 2022