The Sky Tonight: September 2025

The Casual Observer 

September continues nan play of Djilba. This is simply a clip of bedewed upwind but a slow alteration into warmer days. Fittingly, nan Spring Equinox is connected September 23, marking nan opening of astronomical spring. From present connected out, it should get warmer arsenic nan days get person expanding amounts of daylight. 

The Milky Way still stretches crossed nan entity and makes for bully viewing successful nan evenings. The Southern Birds group, made up of nan constellations Pavo, Phoenix, Grus and Tucana makes for fantabulous viewing successful nan southeastern entity each month.  

Caption: The Southern Birds and nan Milky Way make for awesome viewing during September evenings, pinch Southern Cross for reference.
Credit: Stellarium

There is simply a tlunar eclipse – a ‘Blood Moon’ this month, though it’s not for nan early sleepers. Beginning astatine 11:30pm connected September 7, nan Moon will be afloat successful Earth’s protector by 1:30am connected September 8 and will beryllium nan unique acheronian reddish colour that gives these eclipses their name. What’s happening is that faint sunlight scattered done Earth’s ambiance is still capable to scope nan Moon, moreover though it is down nan Earth. Due to nan measurement ray scatters done Earth’s atmosphere, only nan reddish ray makes it each nan measurement to nan Moon, resulting successful nan stunning colour change. The Moon will person wholly passed done earth’s protector by 4:30am connected September 8 and nan eclipse is over.  

Caption: A reddish Moon will beryllium visible to those consenting to enactment up to spot it.
Credit: Public Domain

Correspondingly, location is simply a sister partial star eclipse 2 weeks later connected September 22 complete nan South Pacific Ocean, New Zealand and parts of Antarctica. We won’t beryllium capable to spot this from Perth. 

Saturn is astatine guidance connected September 21. This intends it is precisely other nan Sun successful nan sky. If you constituent 1 manus astatine nan Sun and nan different manus toward Saturn, you will beryllium pointing successful precisely other directions. The observational consequence of this is that Saturn rises arsenic nan Sun sets and will beryllium up each night. This is nan champion clip of twelvemonth to spot nan ringed satellite successful each its glory arsenic it besides intends we will spot nan satellite look on. 

Caption: Saturn is visible successful nan eastbound entity during September evenings.
Credit: Stellarium 

ISS sightings from Perth 

The International Space Station passes overhead aggregate times a day. Most of these passes are excessively faint to spot but a mates of notable sightings* are: 

Table: Times and dates to spot nan ISS from Perth 

Source: Heavens above, Spot nan Station 

*Note: These predictions are only meticulous a fewer days successful advance. Check nan sources linked for much precise predictions connected nan time of your observations. 

Moon phases 

Full Moon: September 8 

Last Quarter: September 14 

New Moon: September 22 

First Quarter: September 30 

Dates of interest 

September 7: Total Lunar Eclipse originates precocious evening and continues into greeting of September 8 

September 14: 10th day of first discovery of gravitational waves 

September 14: Mars adjacent to Spica 

September 21: Saturn astatine opposition 

September 23: Spring equinox 

September 24: Moon adjacent to Mars 

Planets to look for 

Venus and Jupiter still predominate nan eastbound greeting sky. Jupiter moves higher to nan northeast, while Venus gets little successful nan sky, sinking into nan greeting twilight by nan extremity of nan month. They are joined by nan Moon connected September 18 for a bully viewing. 

Caption: Venus and Jupiter successful nan eastbound greeting entity connected September 18.
Credit: Stellarium

Saturn makes for fantabulous viewing each period arsenic its location astatine guidance makes this nan champion clip of twelvemonth to spot it. 

Mars hangs successful nan westbound during nan evenings connected its interminable march crossed nan sky. It’s rather faint now astatine astir magnitude 1.6. It has a adjacent brushwood pinch nan brighter prima Spica connected September 14, passing astir 2 degrees from it. 

Image: Mars is adjacent to Spica connected September 14.
Credit: Stellarium 

Mercury is mislaid successful nan glare of nan Sun this month and is simply a useless portion of sh*t astatine nan champion of times anyway. 

Constellation of nan month 

Scutum nan Shield 

Scutum is simply a mini constellation – nan 5th smallest of them each – located conscionable northbound of Sagittarius, placing it almost straight overhead during September evenings. Astronomer Johannes Hevelius orginally named it Scutum Sobiescianum after Polish King John III Sobieski (‘The Sheild of Sobieski’) but these days we conscionable retrieve nan first portion of it. 

Caption: Scutum is adjacent to Sagittarius successful nan sky.
Credit: Stellarium.

Scutum is different successful that it straddles portion of nan Milky Way but is still rather faint, pinch nan brightest prima successful its boundaries Alpha Scuti being a miniscule magnitude 3.8.  Despite this, successful fact, because it straddles nan Milky Way, it presents nary shortage of astronomical wonders.  

Scutum contains nan fascinating but sadly uninspiringly named planetary nebula IC 1295. Despite their name, planetary nebula person thing to do pinch planets. Rather, erstwhile a Sun-like prima dies of aged property it throws disconnected its outer layers of gas, exposing its basking core. The radiation from nan basking halfway of nan now dormant prima ionises nan expelled gas, causing it to glow successful each sorts of beautiful colours, which gives america nan beautiful images successful our telescopes that we telephone planetary nebulae. The sanction comes from nan days of ye olde – planetary nebulae thin to look information successful style done a telescope, conscionable for illustration planets –  truthful early astronomers named them thus. We now cognize they person thing to do pinch planets. 

Image: Planetary nebula IC 1295 glows greenish from ionised oxygen.
Credit: ESO

Scutum is besides location to nan prima UY Scuti. This prima is 1 of nan largest known stars successful nan galaxy, an palling 900 times wider than nan Sun, astatine minimum. Coming successful astatine 125,000 times brighter than nan Sun, its aboveground would astir apt widen past Jupiter if we placed it successful our Solar System. 

You should really watch this video.  

Objects for nan mini telescope 

Saturn – The jewel of nan Solar System 

The ringed satellite is simply a must spot this month. Rising successful nan early evening arsenic nan Sun sets, it is visible to nan naked oculus arsenic a yellowish blob. A mini scope quickly reveals nan rings and nan noticeable flattening of Saturn astatine its poles arsenic nan planet’s accelerated rotation squashes it out. You mightiness besides spot a mates of its myriad moons. The second half of nan period is nan champion clip for viewing, arsenic Earth’s pesky Moon will beryllium retired of nan way. 

Image: Saturn arsenic it appears during September.
Credit: Stellarium