This is an AI Free Zone: AI writing is everywhere -- except here. Spaceweather.com is written 100% by Dr. Tony Phillips, a carbon-based lifeform with 30 yrs of forecasting experience. If you find a mistake, rest assured it was made by a real human being.
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A HOLE IN THE SUN'S ATMOSPHERE: Make that two holes. A pair of coronal holes (one northern and one southern) are turning toward Earth and sending dual streams of solar wind in our direction. ETA: Sept. 14-16. Their arrival could trigger equinox auroras. Aurora alerts: SMS Text.
BLUEBIRD SATELLITE SIGHTINGS: This weekend, BlueBird satellites have been flying over North America. These are AST SpaceMobile's "cell towers in space" with giant antennas capable of supplying broadband data to phones almost anywhere on Earth. How bright are they? "BlueBird 12 was as bright as Altair," reports Kevin Fetter, who sends these images from Brockville, Ontario:
Altair is magnitude +0.8, which means the BlueBirds are about as bright as first magnitude stars when they pass directly overhead. They outshine typical Starlink satellites by 300 times.
"BlueBird 11 was even brighter just before it passed into Earth's shadow and winked out," he says. This behavior is expected. Just before a BlueBird enters shadow, the sun is almost directly behind the observer, and the satellite's flat antenna bounces sunlight straight back at you.
Get used to them. There are a dozen BlueBirds in orbit now, with AST SpaceMobile planning to have about 45 by the end of 2026. The FCC has authorized up to 248.
Would you like to see a BlueBird with your own eyes? Sign up for Backyard Astronomy Alerts. We'll send you a text message when the "cell towers in space" are about to fly over your hometown.
Realtime Space Weather Photo Gallery
Free: Space Weather Newsletter
THE SPRITE AND THE SEA GOAT: Where is the Sea Goat? Just follow the sprite:
"I was chasing a cluster of thunderstorms in Arizona on Sept 11th when a red spoke of light flashed above the storm tops," says photographer Jeremy Perez. "It pointed to the east edge of Capricornus."
Capricornus *is* the Sea Goat, a goat with the tail of a fish. This strange creature goes back to Babylonian astronomy and later became a fixture in Greek myth. In Perez's photo, a carrot sprite points right at its tail, the 3rd magnitude star Deneb Algedi.
It's Monsoon storm season in the American Southwest, which means now is a good time to catch sprites alongside the desert Milky Way. If you're in the area and see one, submit your photos here.
Realtime Sprite Photo Gallery
Free: Spaceweather.com Newsletter
COSMIC CAT WINE STOPPER: You can't buy this on Amazon. Only the Earth to Sky Store has the Cosmic Cat Wine Stopper. On Dec. 17, 2025, this far-out stopper flew to the stratosphere onboard an Earth to Sky Calculus cosmic ray research balloon:
You can have it for $99.95. The wooden cat is hand carved and painted, and it has an airtight rubber seal that securely plugs bottles of wine or any other beverage. With your stopper, you'll receive a gift card showing the cat in flight and telling the story of its journey to the stratosphere (and back again).
Far Out Gifts: Earth to Sky Store
All sales support hands-on STEM education
Realtime Aurora Photo Gallery
Free: Spaceweather.com Newsletter
Every night, a network
of
NASA
all-sky cameras scans the skies above the United
States for meteoritic fireballs. Automated software
maintained by NASA's Meteoroid Environment Office
calculates their orbits, velocity, penetration depth
in Earth's atmosphere and many other characteristics.
Daily results are presented here on Spaceweather.com.
On September 13, 2026, the network reported 7 fireballs.
(6 sporadics, 1 September epsilon Perseid)
In this diagram of the inner solar system, all of the fireball orbits intersect at a single point--Earth. The orbits are color-coded by velocity, from slow (red) to fast (blue).
[Larger image] [movies]
Potentially Hazardous Asteroids (
PHAs)
are space rocks larger than approximately 100m that
can come closer to Earth than 0.05 AU. None of the
known PHAs is on a collision course with our planet,
although astronomers are finding
new
ones all the time.
On September 13, 2026 there were 2349 potentially hazardous asteroids.
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Recent
& Upcoming Earth-asteroid encounters:
| Asteroid |
Date(UT) |
Miss Distance |
Velocity (km/s) |
Diameter (m) |
| 2026 RR1 |
2026-Sep-08 |
1.4 LD |
13.6 |
9 |
| 2026 RD4 |
2026-Sep-08 |
11.6 LD |
10.8 |
20 |
| 2024 RV12 |
2026-Sep-08 |
4 LD |
11.9 |
22 |
| 2026 RN2 |
2026-Sep-08 |
0.6 LD |
12.1 |
5 |
| 2026 RT1 |
2026-Sep-08 |
18.9 LD |
7.5 |
28 |
| 2026 RK15 |
2026-Sep-08 |
2.2 LD |
1.8 |
3 |
| 2026 RS10 |
2026-Sep-08 |
1.7 LD |
17 |
54 |
| 2026 RK10 |
2026-Sep-09 |
1 LD |
12 |
10 |
| 2026 RB4 |
2026-Sep-09 |
4.9 LD |
9.9 |
19 |
| 2026 RY1 |
2026-Sep-09 |
1.5 LD |
4.1 |
2 |
| 2026 RY14 |
2026-Sep-09 |
3 LD |
7.7 |
9 |
| 2026 RE15 |
2026-Sep-09 |
7.3 LD |
7.9 |
13 |
| 2026 RM10 |
2026-Sep-09 |
2.8 LD |
8.9 |
16 |
| 2026 RH10 |
2026-Sep-10 |
0.6 LD |
18.2 |
14 |
| 2026 RP2 |
2026-Sep-10 |
14 LD |
5.6 |
14 |
| 2026 RW3 |
2026-Sep-10 |
1.1 LD |
9.5 |
11 |
| 2026 RW10 |
2026-Sep-10 |
12.7 LD |
14.2 |
27 |
| 2009 SK |
2026-Sep-10 |
18.5 LD |
8.1 |
34 |
| 2026 RV1 |
2026-Sep-10 |
1.8 LD |
7.7 |
8 |
| 2026 RQ10 |
2026-Sep-10 |
10.5 LD |
9.1 |
25 |
| 2026 OH3 |
2026-Sep-11 |
12.4 LD |
20.2 |
190 |
| 2026 RG4 |
2026-Sep-11 |
3.4 LD |
3 |
14 |
| 2026 RZ14 |
2026-Sep-11 |
3.4 LD |
6.4 |
9 |
| 2026 RJ |
2026-Sep-11 |
4.4 LD |
6.9 |
23 |
| 2026 RD1 |
2026-Sep-11 |
5.5 LD |
6.9 |
17 |
| 2025 RQ2 |
2026-Sep-11 |
17.5 LD |
12.1 |
17 |
| 2026 RD15 |
2026-Sep-12 |
7.3 LD |
19.1 |
33 |
| 2026 RQ15 |
2026-Sep-12 |
5.1 LD |
16.2 |
17 |
| 2026 RL10 |
2026-Sep-12 |
2.4 LD |
2.7 |
15 |
| 2026 RG2 |
2026-Sep-13 |
2.1 LD |
5.4 |
15 |
| 2026 RF2 |
2026-Sep-13 |
9.2 LD |
10.3 |
10 |
| 2026 RP10 |
2026-Sep-13 |
6.8 LD |
15.4 |
24 |
| 2010 FX9 |
2026-Sep-14 |
9.4 LD |
11.1 |
55 |
| 2025 SC |
2026-Sep-14 |
19.2 LD |
1.9 |
3 |
| 2026 RO10 |
2026-Sep-14 |
14.6 LD |
9.3 |
61 |
| 2026 RG15 |
2026-Sep-15 |
0.2 LD |
9.1 |
25 |
| 2024 RP12 |
2026-Sep-15 |
18.5 LD |
6.6 |
51 |
| 2026 RA4 |
2026-Sep-16 |
3.4 LD |
11.6 |
20 |
| 2026 NT2 |
2026-Sep-17 |
16.1 LD |
12.5 |
310 |
| 2026 RN4 |
2026-Sep-17 |
16.4 LD |
9.1 |
19 |
| 2026 RF15 |
2026-Sep-19 |
5.5 LD |
14.1 |
27 |
| 2026 RH3 |
2026-Sep-19 |
17.2 LD |
11.7 |
27 |
| 2026 RP1 |
2026-Sep-20 |
20.1 LD |
17.3 |
41 |
| 2026 RZ1 |
2026-Sep-22 |
10.4 LD |
9.1 |
37 |
| 2026 RJ15 |
2026-Sep-22 |
5.5 LD |
10.3 |
18 |
| 2026 RN15 |
2026-Sep-27 |
8.4 LD |
6.5 |
21 |
| 2026 RS |
2026-Sep-30 |
11.2 LD |
6 |
24 |
| 2018 SP2 |
2026-Sep-30 |
5 LD |
14.3 |
39 |
| 2024 SH7 |
2026-Oct-04 |
10.5 LD |
10.8 |
12 |
| 2024 TD16 |
2026-Oct-07 |
14.2 LD |
11.8 |
17 |
| 2015 TS238 |
2026-Oct-08 |
4.7 LD |
15.8 |
30 |
| 2019 SD8 |
2026-Oct-10 |
18.7 LD |
9.5 |
12 |
| 2022 UP6 |
2026-Oct-15 |
2.6 LD |
9 |
8 |
| 2000 SZ162 |
2026-Oct-16 |
19.9 LD |
5.7 |
12 |
| 2020 FN3 |
2026-Oct-20 |
12.4 LD |
5.8 |
45 |
| 2017 UX7 |
2026-Oct-22 |
17 LD |
10.3 |
27 |
| 2018 GS1 |
2026-Oct-28 |
11.1 LD |
9.3 |
108 |
| 2022 UV21 |
2026-Oct-29 |
14.8 LD |
9.6 |
13 |
| 2025 UK9 |
2026-Oct-31 |
0.8 LD |
7.8 |
4 |
| 524522 |
2026-Nov-02 |
15.7 LD |
8.7 |
277 |
| 2021 VC4 |
2026-Nov-03 |
6 LD |
11.2 |
15 |
| 2017 WJ2 |
2026-Nov-05 |
15.6 LD |
11.8 |
118 |
| 2016 VZ1 |
2026-Nov-05 |
20 LD |
13.5 |
21 |
| 2001 KF54 |
2026-Nov-06 |
18.9 LD |
16.4 |
391 |
| 2025 UF5 |
2026-Nov-09 |
18.9 LD |
1.9 |
10 |
| 2015 VH65 |
2026-Nov-10 |
9.7 LD |
8 |
10 |
| 2012 YD7 |
2026-Nov-10 |
18.6 LD |
7.5 |
49 |
| 2023 VF3 |
2026-Nov-11 |
8.5 LD |
8.8 |
19 |
Notes: LD means
"Lunar Distance." 1 LD = 384,401 km, the distance
between Earth and the Moon. 1 LD also equals 0.00256
AU.
| |
Cosmic Rays in the Atmosphere |
SPACE WEATHER BALLOON DATA: Almost once a week, Spaceweather.com and the students of Earth to Sky Calculus fly space weather balloons to the stratosphere over California. These balloons are equipped with sensors that detect secondary cosmic rays, a form of radiation from space that can penetrate all the way down to Earth's surface. Our monitoring program has been underway without interruption for 10 years, resulting in a unique dataset of in situ atmospheric measurements.
Latest results (Nov. 2024): Atmospheric radiation is sharply decreasing in 2024. Our latest measurements in November registered a 10-year low:
What's going on? Ironically, the radiation drop is caused by increasing solar activity. Solar Cycle 25 has roared to life faster than forecasters expected. The sun's strengthening and increasingly tangled magnetic field repels cosmic rays from deep space. In addition, solar coronal mass ejections (CMEs) sweep aside cosmic rays, causing sharp reductions called "Forbush Decreases." The two effects blend together to bring daily radiation levels down.
.Who cares? Cosmic rays are a surprisingly "down to Earth" form of space weather. They can alter the chemistry of the atmosphere, trigger lightning, and penetrate commercial airplanes. According to a study from the Harvard T.H. Chan school of public health, crews of aircraft have higher rates of cancer than the general population. The researchers listed cosmic rays, irregular sleep habits, and chemical contaminants as leading risk factors. A number of controversial studies (#1, #2, #3, #4) go even further, linking cosmic rays with cardiac arrhythmias and sudden cardiac death.
Technical notes: The radiation sensors onboard our helium balloons detect X-rays and gamma-rays in the energy range 10 keV to 20 MeV. These energies span the range of medical X-ray machines and airport security scanners.
Data points in the graph labeled "Stratospheric Radiation" correspond to the peak of the Regener-Pfotzer maximum, which lies about 67,000 feet above central California. When cosmic rays crash into Earth's atmosphere, they produce a spray of secondary particles that is most intense at the entrance to the stratosphere. Physicists Eric Regener and Georg Pfotzer discovered the maximum using balloons in the 1930s and it is what we are measuring today.
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The
official U.S. government space weather bureau |
| |
The
first place to look for information about sundogs,
pillars, rainbows and related phenomena. |
| |
Researchers
call it a "Hubble for the sun." SDO
is the most advanced solar observatory ever. |
| |
3D
views of the sun from NASA's Solar and Terrestrial
Relations Observatory |
| |
Realtime
and archival images of the Sun from SOHO. |
| |
information about sunspots based on the latest NOAA/USAF Active Region Summary |
| |
current counts of failed and deployed Starlink satellites from Jonathan's Space Page. See also, all satellite statistics. |
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Authoritative predictions of space junk and satellite re-entries |
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from
the NOAA Space Environment Center |
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fun to read, but should be taken with a grain of salt! Forecasts looking ahead more than a few days are often wrong. |
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from the NOAA Space Environment Center |
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the
underlying science of space weather |
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Got a chipped or cracked windshield that prevents you from seeing space weather events while driving? Get windshield replacement from SR Windows & Glass with free mobile auto glass service anywhere in the Phoenix area. |
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