Visitors to the Observatory must fill in an indemnity form.
The forms are available from the ASSAJhb coordinator at the event or can be downloaded from the link.
Completed forms must be handed to the ASSAJHB coordinator.

Notice of Next Meeting

Our next monthly meeting takes place on:

Indemnity Form Download.

  • Date: Wednesday 11 July 2018
  • Time: 19h00 for 19h30
  • Location: Jhb. Observatory
  • Presenter: AGM
  • Topic: AGM
  • Donation: R20 pp for tea and snacks

Meetings generally last about one and a half hours, and include a Topic of Interest, What’s Up in the Night Sky, and the Main Speaker’s Presentation. Tea and coffee are served afterwards. Visitors are welcome.

Click here for directions and a map to the Observatory

Sky and Braai

Our next monthly Braai takes place on:

Indemnity Form Download.

  • Date: Sunday 24 June 2018
  • Time: 16h30
  • Location: Jhb. Observatory, Top of the hill at the Herbert Baker Library. Map.
  • Topic: Whats Up – a detailed overview af some objects.
  • Donation: R20 pp for the fire wood. Children under 15 free.


  • 16h30  – Arrival and Fires started
  • 17h00 – Braai
  • 18h00 –  Presentation
  • 18h20 – 10 min Break
  • 18h30 – Viewing
  • 20h00 –  close domes and lock up.

Our fire glows warmly with a spirit of friendship settling to waft delicious aromas that pervade the olfactory nerves, creating intense appeal for taste buds.

Read More.

The murmering and chuckling displays delight, comfort and contemplative joy at what will be seen in the sky tonight. Bursts of joyous laughter bring one back to the chatter and fun of the evening. Do join ASSA JHB on the hill for a lovely evening of sky and braai. Dress warmly, bring along your meat to braai, your condiments, drinks and salads, anything you need for your meal, hmm… fingers were invented before knives and forks? and  oops, do not forget a chair or ‘situpon’. You may bring your own telescope if you want to.


Public Viewing Evenings:

Indemnity Form Download.

  • Jan –
  • Feb – 23   Lunar Phase 1st Quarter
  • Mar – 23   Lunar Phase 1st Quarter
  • Apr – 20   Lunar Phase 1st Quarter
  • May – 18  Lunar Phase 17%
  • Jun – 22   Lunar Phase 73%
  • Jul – 20    Lunar Phase 60%
  • Aug – 17  Lunar Phase 1st Quarter
  • Sep – 14  Lunar Phase 28%
  • Oct – 12  Lunar Phase 14%
  • Nov – 16  Lunar Phase 60%
  • Donation: R20 pp. Children under 15 free.

Public Viewing Evenings take place at the Observatory – click here for directions and a map to the Observatory.

Please follow @JoosteJerome on Twitter or visit our Facebook page at for confirmation


  • Date: 27 July 2018.
  • Time: 18h00
  • Location: Jhb. Observatory, Top of the hill at the Herbert Baker Library. Map.
  • Donation: R20 pp. Children under 15 free.
  • Indemnity Form Download.

Memorable Magic Moments:

Very seldom do we have such enticing moments as the happenings in our Night Skies. Join ASSAJHB  at the Observatory on the hill top and enjoy ecliptic memories. Come and see this marvellous event through telescopes on the hill. Just imagine the stark beauty and dream about travelling there one day.

Specials to feast your eyes on:

The Moon and Mars will travel close together, brilliant shiny twins on the night of the Lunar Eclipse. Rusty ol’ Mars will be dressed in brightest magnificence for its closest approach to Earth from 27 to 30 July. Moon and Mars will be roughly 6 degrees apart. Together,  both will be visible in a pair of Celestron binoculars 8 x40 with a fov of 8.2 degrees. Its closest approach to Earth is July 31. That is the point in Mars’ orbit, when it comes closest to Earth. Mars will be at a distance of 35.8 million miles (57.6 million kilometers).


Sourced from

The animation shows what the eclipse approximately looks like in Johannesburg. Stages and times of the eclipse are outlined below. All times are local time (SAST) for Johannesburg.


Time Phase Direction Altitude
19:14 Fri, 27 Jul
Penumbral Eclipse beginsThe Earth’s penumbra start touching the Moon’s face. Map direction East100°


20:24 Fri, 27 Jul
Partial Eclipse beginsPartial moon eclipse starts – moon is getting red. Map direction East94°


21:30 Fri, 27 Jul
Total Eclipse beginsTotal moon eclipse starts – completely red moon. Map direction East87°


22:21 Fri, 27 Jul
Maximum EclipseMoon is closest to the center of the shadow. Map direction East80°


23:13 Fri, 27 Jul
Total Eclipse endsTotal moon eclipse ends. Map direction East-northeast66°


00:19 Sat, 28 Jul
Partial Eclipse endsPartial moon eclipse ends. Map direction North358°


01:28 Sat, 28 Jul
Penumbral Eclipse endsThe Earth’s penumbra ends. Map direction West-northwest291°


Sourced from


Astronomy - ASSA Johannesburg Centre
Astronomy - ASSA Johannesburg Centre shared a link.Thursday, June 14th, 2018 at 5:45pm
Astronomy - ASSA Johannesburg Centre
Astronomy - ASSA Johannesburg Centre shared NASA ScienceCasts's video.Wednesday, June 6th, 2018 at 9:10am
Astronomy - ASSA Johannesburg Centre
NASA ScienceCasts
As the Juno spacecraft orbits Jupiter, new discoveries about the giant planet continue to be made.
Astronomy - ASSA Johannesburg Centre
Astronomy - ASSA Johannesburg Centre shared a link.Monday, June 4th, 2018 at 8:25am


Friday, November 24th, 2017 at 4:55am
Public Viewing
CANCELLED due to poor weather
Friday, October 27th, 2017 at 8:58am
Public Viewing
Johannesburg Observatory

Cancelled due to weather.
Friday, September 29th, 2017 at 8:07am
JHB Observatory
Public Viewing 29 September
Cancelled due to poor weather
Sunday, September 24th, 2017 at 10:47am
Sky and Braai - Cancelled - weather deteriorating -clouds and particulate in atmosphere.
Tuesday, September 5th, 2017 at 12:45pm
Monthly Meeting
Date : 13 Sep
Speaker : Heystek Grobler - HartRAO
Topic : Introduction to Radio Astronomy

In the Night Sky


Winter is right on our doorstep. What is more exciting than our clear winter

Venus leaves us as our evening star, be sure to view it as soon after sunset
as possible. Orion is down but the magnificence of Scorpious spreads across
our eastern skies.

All around it are so many galaxies and nebula to view and to photograph.

Do not forget the moon and sun, cloudless skies bring lots of fun.

Moon Phases:

Universe Today

In March of 2015, NASA’s Dawn mission became the first spacecraft to visit the protoplanet Ceres, the largest body [...]

Sun, Jun 17, 2018
Source: Universe Today

In 2006, NASA’s Mars Reconnaissance Orbiter (MRO) established orbit around the Red Planet. Using an advanced suite of scientific [...]

Sat, Jun 16, 2018
Source: Universe Today

The soccer ball used to kick off the FIFA World Cup in Russia on Thursday (June 14) floats weightlessly in [...]
Mon, Jun 18, 2018
President Trump will sign a new space policy directive June 18 addressing space traffic management issues. [...]
Mon, Jun 18, 2018

NASA's nearly 15-year-old rover has hunkered down to ride out some pretty poor weather. [...]
Fri, Jun 15, 2018
Saturn approaches peak visibility, Neptune reverses course, and the Summer Triangle dominates the night sky this week. [...]
Fri, Jun 15, 2018


The five naked-eye planets, Mercury, Venus, Mars, Jupiter and Saturn,

The five naked-eye planets, Mercury, Venus, Mars, Jupiter and Saturn,

Source: APOD
How big is our Sun compared to other stars?

How big is our Sun compared to other stars?

Source: APOD