Astronomy News for the Month of September 2025


    This news letter is provided as a service by
The International Association for Astronomical Studies
provides this newsletter as a service for interested persons worldwide.

Downloadable version of the newsletter in
PDF Format
(Right click and select "Save target as" to begin download.)
(Always check the PDF link above if the web page is not updated.
I always publish the PDF before I upload the web page.)
PDF updated 1st of every month!

Visit the Home Page of KIØAR

Subscribe to the
IAAS Monthly Astronomy Newsletter

(Email version)
SUBSCRIBE

Subscription notes below.


Donate to the IAAS!
Your contributions are tax deductible.
Thank you for your support!


Web and email hosting by

TotalChoice Hosting


Locations of Site Visitors
Create your own visitor map!



An Open Invitation

For amateur radio operators and scanner enthusiasts around the world, please join the Colorado Astronomy Net on the Rocky Mountain Radio League's K1DUN repeater on 449.450 MHz or other digital and analog repeaters, Allstar nodes, Echolinks, DMR and internet links connected to the SKYHUBLINK system. The net meets on Tuesday nights at 7 P.M. Mountain Time (US) (Wednesday at 0200 GMT). Connecting to the SkyHubLink system has expanded our coverage in the U.S., Canada and internationally. All Amateur radio operators worldwide are welcome. Anyone may listen to the net. The RMRL provides a "Live Audio Feed" using Broadcastify.

The Colorado Astronomy Net is now on YouTube!!
All are welcome to join us Tuesday evenings!

Obtain your Amateur Radio (Ham) License or your General Radio Operator's License (GROL)! Visit the South Metro VE Team website for more information. The South Metro VE Team provides test sessions by appointment only. Check the website for current information. All others interested in Amateur Radio, check out the Amateur Radio Relay League website to find out more information about becoming an Amateur Radio operator.

The Colorado Astronomy Net and the IAAS are on Facebook.
Please be sure to "Like" us!

Donate to the IAAS!
Your contributions are tax deductible.
Thank you for your support!


 Excerpts from JPL mission updates are provided as a public service as part
of the JPL Solar System Ambassador/NASA Outreach program.

For special JPL programs and presentations in your area visit the JPL Solar System Ambassador website.
(Click on the logo to link to the JPL SSA homepage.)


Rocket Report for 09/16/2025 through 09/30/2025
Courtesy of "The Rocketman" Ed W6RDZ
Updated Weekly on Tuesday evenings
prior to the Colorado Astronomy Net

In this Newsletter...


Background screen credits: NGC5775
Imaged March 21/22, 2001
using the 16" Kitt Peak Visitors Center telescope
as part of the Kitt Peak Advanced Observing Program.


"The mighty planet Saturn reaches opposition this month, showing narrow rings and plenty of moon transits. This Hubble image captured a transit of the moon Enceladus its shadow, roughly centered together above the rings." Astronomy Magazine, September 2025, p. 28. - HUBBLE HERITAGE TEAM (AURA/STSCI/NASA/ESA)


The Month At-A-Glance
A calendar displaying the daily astronomical events.


20 day moon

The Moon

Phases

Apogee/Perigee

Moon/Planet Pairs

For reference: The Full Moon subtends an angle of ~0.5°.

Return to Top


Calendar of All Astronomical Events 2025

The Planets & Dwarf Planets

Planetary Reports generated by "TheSkyX" software. These reports provide predicted data for the planets for the first of each month for the current year. The rise and set times for the Sun and the Moon for each day of the month as well as meteor shower radiants are also included in the reports. These reports have been optimized for the Denver, Colorado location, however, the times will be approximate for other locations on Earth.

(Times are Mountain Daylight Time (MDT/MST) unless otherwise noted. Times will vary slightly depending on your location.)

Planetary Highlights for September

"September's sky is rich with opportunities. Titan's shadow continues to transit Saturn. The ringed planet reaches opposition along with Neptune, with both worlds in the same region of the sky. Mars is descending toward solar conjunction. Uranus is a fine binocular target, while Jupiter dominates the early morning. Venus starts the month near M44, then inches closer to a conjunction with Regulus and the crescent Moon." Astronomy Magazine, September 2025, p.28.

Mercury

Mercury is at superior conjunction on the 13th. Mercury rises at 5:30 a.m. on the 1st. After conjunction, Mercury returns to the evening sky, setting about 7:13 p.m. by month's end. Mercury is visible about 30 minutes before sunrise just above the eastern horizon after the first week of the month, and about 30 minutes after sunset to the west during the last week of the month. Mercury moves from the constellation of Leo into Virgo shining at magnitude -1.3 on the 1st.

Venus

Rises about 3:52 a.m. on the 1st and about 4:57 a.m. by month's end. Look for Venus to the east-southeast about an hour before sunrise. Venus moves from the constellation of Cancer into Leo shining at magnitude -3.9 on the 15th.

Earth

The Autumnal equinox occurs at 2:19 P.M. EDT on the 22nd.

Mars

Sets at 8:58 p.m. on the 1st and about 7:49 p.m. by month's end. Look for Mars low to the west in the evening about 30 minutes after sunset. Mars is in the constellation of Virgo shining at magnitude 1.6.

Jupiter

Rises at 2:13 a.m. on the 1st and about 12:37 a.m. by month's end. Look for Jupiter to the south in the early morning hours before dawn. Jupiter is in the constellation of Gemini shining at magnitude -2.0.

Saturn

Is at opposition on the 21st, rising as the Sun sets. Saturn rises at 8:22 p.m. on the 1st and about 6:19 p.m. by month's end. Look for Saturn low to the east late in the evening. Saturn is at its best viewing for the year. Saturn is in the constellation of Pisces shining at magnitude 0.6.

Uranus

Is stationary on the 6th. Uranus rises at about 10:57 p.m. on the 1st and about 8:58 p.m. by month's end. Look for Uranus to the southeast in the late evening. Uranus is in the constellation Taurus shining at magnitude 5.7.

Neptune

Is at opposition on the 23rd, rising as the Sun sets. Neptune rises at 8:20 p.m. on the 1st and about 6:21 p.m. by the month's end. Look for Neptune low to the east late in the evening within 1° of Saturn all month. Neptune is in the constellation of Pisces shining at magnitude 7.7.

Dwarf Planets

Ceres

Rises at 9:55 p.m. on the 1st and about 7:46 p.m. by month's end. Ceres can be spotted low to the south near midnight when it is highest in the sky. Ceres is in the constellation of Cetus shining at magnitude 7.8.

Pluto

Rises at 5:53 p.m. on the 1st and about 3:54 p.m. by month's end. The best time to spot Pluto will be in the late evening when it is highest in the sky to the south. Pluto is in the constellation of Capricornus shining at magnitude 15.2.

As always, good luck at spotting Neptune, Ceres and Pluto, a large telescope and dark skies will be needed.

Constellation information provided by Go Astronomy.

Return to Top


Astronomical Events

Meteor Showers

  • "NO MAJORMETEOR SHOWERS are active in September, so we enter a bit of a lull after the excitement of August.

    Meteoritic dust from thousands of comets passing over the eons is visible before dawn as the zodiacal light, as sunlight reflecting off the dust creates a faint glow. You'll need a very dark eastern horizon with no streetlights nearby; higher elevations get a better view, too.

    The zodiacal light appears as a faint cone-shaped glow aligned with the ecliptic. On September mornings well before dawn, the high angle of the ecliptic benefits views of it. The broad base of the glow is in Leo as that constellation rises, and narrows higher in the sky through Cancer and Gemini. Catch it on moonless nights in the third and fourth week of September for the darkest skies." Astronomy Magazine, September 2025, p.29.

    Meteor Shower Radiant Report

    For more information about Meteor Showers, visit Gary Kronk's Meteor Showers Online web page.

    Meteor Scatter (or Meteor burst communications) - "is a radio propagation mode that exploits the ionized trails of meteors during atmospheric entry to establish brief communications paths between radio stations up to 2,250 kilometres (1,400 mi) apart." Tune your shortwave or your HF amateur radio to 54.310 MHz SSB and see if you can hear any pings. Try other frequencies as well... 6m FT8 digital - 50.313 Mhz & 50.276 Mhz, JP-65 digital mode and the carrier frequencies of the lower VHF bands for TV channels 2, 3 & 4.

    Meteor Rx How-To by Terry Bullett (WØASP)

  • Comets

  • Comet C/2024 E1 (Wierzchos´) is passing through the constellation of Corona Borealis high to the west in the evening. Mid-month will be the easiest time this month to spot the comet shining around 12th to 10th magnitude. An 8 inch scope or greater and dark skies will be needed to view it.

  • For information, orbital elements and ephemerides on observable comets, visit Observable Comets.

    For more information about Comets, visit Gary Kronk's Cometography.com webpage.

  • Eclipses

    Solar Eclipses

  • A partial solar eclipse occurs on the 21st. This eclipse is visible from New Zealand, plus a thin strip of Australia’s eastern coast, various Pacific islands, and parts of Antarctica.

    Lunar Eclipses

  • The longest total lunar eclipse since 2022 occurs on the 7th. Totality will be visible from Australia, Asia, Africa, and Europe—around 85% of the world's population has a chance to see this eclipse.

  • Observational Opportunities

  • Look for Mars in the early evening to the west.
  • Look for Pluto to the south.
  • Look for Saturn, Neptune and Ceres in the late evening and early morning to the south.
  • Look for Uranus, Jupiter, Venus and Mercury in the morning to the east.

  • Asteroids

    (From west to east)
    • Vesta is in the constellation of Libra.
    • Pallas is in the constellation of Aquila.
    • Julia is in the constellation of Aquarius .
    • Hebe is in the constellation of Aquarius.
    • Papagena is in the constellation of Taurus.

    • Information about the Minor Planets can be found at the Minor Planet Observer website.
    Ocultations

    IOTA Logo

  • Information on various occultations can be found by clicking the IOTA logo.

  • Return to Top


    Member Meteor Sightings

    In this section I will post meteor, fireball, etc sightings that have been published on the American Meteor Society's web site. I want to make this an active section of the web pages and newsletter and would like to publish the links to member sightings. If you have any published sightings, please provide me with the links and I will post them here for all to enjoy.

    Event ID Date/Time Location Observer Link
    3871-2015 2015-11-13 01:55 MST CO Charles N 3871a
    3587-2015 2015-11-22 17:38 MST CO Kevin S 3587aw
    3829-2015 2015-12-05 18:06 MST CO Burness A 3829a
      986-2020 2020-02-21 22:20 MST CO Lukas S 986
    3716-2020 2020-07-24 23:22 MDT CO Lukas S 3716
    4774-2021 2021-08-13 21:57 MDT UT Lukas S 4774
    7044-2021 2021-10-28 20:37 MDT CO Burness A 249058
    6763-2022 2022-10-06 05:56 CDT OK Mike C 6763
    5300-2023 2023-09-11 22:04 MDT CO Lukas S 5300
    578-2024 2024-01-28 23:05 MST CO Lukas S 578

    Return to Top


    Subscriber Gallery