AI writing is everywhere -- except here. This website is written by Dr. Tony Phillips, a carbon-based lifeform with 30 yrs of forecasting experience. Our guarantee: If you find a mistake, it was made by a real human being.
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GEOMAGNETIC STORM WATCH (G1): Minor G1-class geomagnetic storms are possible on Sept. 23-24 when a fast-moving stream of solar wind is expected to reach Earth. This stream is coming from a canyon-shaped hole in the sun's atmosphere. The Russell-McPherron effect could turn it into a nice display of equinox auroras. Aurora alerts: SMS Text
WE'VE TURNED STARLINK INTO A PLANETARY BAROMETER: Starlink has many downsides: The megaconstellation interferes with astronomy, pollutes the atmosphere with metallic re-entry debris, and has pushed Low Earth Orbit to the brink of the Kessler Syndrome.
On the other hand, it makes a terrific barometer.
Earth is surrounded by more than 11,000 Starlink satellites. Without exception, they all skim the outermost layers of our atmosphere where air pressure and aerodynamic friction rob them of orbital energy. Every single Starlink would fall back to Earth if they didn't occasionally boost themselves with thrusters.
As an experiment, we decided to use the Starlink megaconstellation as a giant sensor for air pressure and drag. Here's how it works: Every day, the US Space Force publishes fresh orbital elements (also known as "TLEs") for every object in Earth orbit. Buried in each TLE is a drag term. We download the daily drag terms for thousands of Starlinks and convert them into one easy-to-understand number: The sink rate.
You can find the sink rate right here. A value of, say, 30 m/day, means that a typical Starlink at 480 km will fall 30 meters/day due to aerodynamic drag. Why 480 km? Because that's where most Starlinks are located.
Starlinks aren't the only ones we're tracking. We monitor 3 other independent constellations: Planet Labs' SuperDoves (107), Amazon's Kuiper satellites (391), and Eutelsat's OneWeb satellites (651). These provide a check on the Starlink numbers. The SuperDoves are particularly valuable because they have no thrusters to combat drag, making them exquisitely sensitive.
Using this new data stream, we can watch the atmosphere breathe. The envelope of air around our planet expands and contracts in response to solar activity. Big geomagnetic storms puff up the atmosphere and cause sharp spikes in the sink rate.
Thank you, Starlink? Come back tomorrow for the latest drag.
Realtime Space Weather Photo Gallery
Free: Space Weather Newsletter
THE HARVEST MOON CUBE: On Aug. 22nd, the students of Earth to Sky Calculus launched a cosmic ray balloon to the stratosphere. This laser-etched Harvest Moon Cube went along for the ride, ascending to an altitude of 101,140 feet:
You can have it for $119.95. The students are selling this premium K9-crystal cube as a fund-raiser for their cosmic ray ballooning program. It's an authentic representation of the Moon, with all of the craters, mountains and lava plains accurately portrayed.
With your order, you will also receive a unique gift card showing the cube floating at the top of Earth's atmosphere. The interior of the card tells the story of the flight and confirms that this gift has been to the edge of space 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
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 22, 2026, the network reported 24 fireballs.
(24 sporadics)
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 23, 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 SF8 |
2026-Sep-17 |
1.2 LD |
11.2 |
5 |
| 2026 RB39 |
2026-Sep-17 |
1 LD |
9.3 |
7 |
| 2026 NT2 |
2026-Sep-17 |
16.1 LD |
12.5 |
314 |
| 2026 RN4 |
2026-Sep-17 |
16.2 LD |
8.9 |
19 |
| 2026 SE |
2026-Sep-17 |
6.2 LD |
8.2 |
11 |
| 2026 SU2 |
2026-Sep-17 |
4.8 LD |
11.4 |
10 |
| 2026 RD38 |
2026-Sep-17 |
15.2 LD |
8.2 |
35 |
| 2026 SJ |
2026-Sep-18 |
6.9 LD |
8.5 |
15 |
| 2026 SO2 |
2026-Sep-18 |
5.3 LD |
9.8 |
20 |
| 2026 SR2 |
2026-Sep-18 |
3.2 LD |
7 |
8 |
| 2026 SG1 |
2026-Sep-18 |
14.4 LD |
10 |
26 |
| 2026 SW |
2026-Sep-18 |
10.8 LD |
8.4 |
18 |
| 2026 SK |
2026-Sep-19 |
4.3 LD |
16.2 |
17 |
| 2026 RF15 |
2026-Sep-19 |
5.5 LD |
14.1 |
27 |
| 2026 RH3 |
2026-Sep-19 |
17.2 LD |
11.7 |
29 |
| 2026 SS2 |
2026-Sep-20 |
5.6 LD |
10.6 |
37 |
| 2026 SA |
2026-Sep-20 |
4.2 LD |
10.6 |
17 |
| 2026 SF1 |
2026-Sep-20 |
15 LD |
6.2 |
19 |
| 2026 SH |
2026-Sep-20 |
10.2 LD |
13.3 |
25 |
| 2026 SG |
2026-Sep-20 |
3.2 LD |
14.5 |
25 |
| 2026 SS |
2026-Sep-20 |
2 LD |
15.5 |
8 |
| 2026 RP1 |
2026-Sep-20 |
19.9 LD |
17.1 |
42 |
| 2026 RW37 |
2026-Sep-20 |
1.2 LD |
8.7 |
8 |
| 2026 SZ2 |
2026-Sep-20 |
0.1 LD |
8 |
3 |
| 2026 SP2 |
2026-Sep-20 |
17.8 LD |
9.7 |
19 |
| 2026 SY |
2026-Sep-21 |
5.6 LD |
9.8 |
20 |
| 2026 SN2 |
2026-Sep-21 |
2.5 LD |
13.5 |
11 |
| 2026 SD3 |
2026-Sep-21 |
5.4 LD |
18.4 |
25 |
| 2026 SY2 |
2026-Sep-21 |
2.4 LD |
25.1 |
11 |
| 2026 SL |
2026-Sep-21 |
6.2 LD |
14.3 |
17 |
| 2026 SW11 |
2026-Sep-21 |
2 LD |
7.3 |
10 |
| 2026 RG39 |
2026-Sep-21 |
6.8 LD |
5.1 |
9 |
| 2026 RZ1 |
2026-Sep-22 |
10.4 LD |
9.1 |
36 |
| 2026 RD49 |
2026-Sep-22 |
15.8 LD |
3.7 |
18 |
| 2026 RA38 |
2026-Sep-22 |
14.7 LD |
8 |
24 |
| 2026 RJ15 |
2026-Sep-22 |
5.5 LD |
10.2 |
20 |
| 2026 SP |
2026-Sep-23 |
4.3 LD |
9.7 |
11 |
| 2026 SE1 |
2026-Sep-23 |
2.8 LD |
15.4 |
12 |
| 2026 RR34 |
2026-Sep-23 |
3.7 LD |
6.5 |
18 |
| 2026 RQ34 |
2026-Sep-24 |
13 LD |
7 |
24 |
| 2026 ST2 |
2026-Sep-24 |
15.9 LD |
13.7 |
42 |
| 2026 RC49 |
2026-Sep-24 |
11.1 LD |
8 |
22 |
| 2026 SC |
2026-Sep-25 |
1.7 LD |
7.8 |
19 |
| 2026 RN15 |
2026-Sep-27 |
8.4 LD |
6.5 |
21 |
| 2026 SA8 |
2026-Sep-28 |
1 LD |
6.6 |
7 |
| 2026 SL7 |
2026-Sep-28 |
17.7 LD |
26.9 |
46 |
| 2026 SX2 |
2026-Sep-28 |
4.1 LD |
7.7 |
13 |
| 2026 RS |
2026-Sep-30 |
11.2 LD |
6 |
25 |
| 2026 RX38 |
2026-Sep-30 |
10 LD |
14.3 |
33 |
| 2018 SP2 |
2026-Sep-30 |
5 LD |
14.3 |
39 |
| 2019 AS2 |
2026-Oct-02 |
4.5 LD |
7.3 |
49 |
| 2026 RP39 |
2026-Oct-03 |
6.1 LD |
6.1 |
21 |
| 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 |
| 2022 MP2 |
2026-Nov-13 |
19.8 LD |
3.8 |
23 |
| 2025 VG5 |
2026-Nov-13 |
18.2 LD |
4.9 |
16 |
| 2023 VE6 |
2026-Nov-17 |
18.4 LD |
10.1 |
13 |
| 2019 WT1 |
2026-Nov-18 |
19.7 LD |
9.7 |
16 |
| 2018 NE1 |
2026-Nov-19 |
16.7 LD |
13.3 |
74 |
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 |
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The
first place to look for information about sundogs,
pillars, rainbows and related phenomena. |
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Researchers
call it a "Hubble for the sun." SDO
is the most advanced solar observatory ever. |
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3D
views of the sun from NASA's Solar and Terrestrial
Relations Observatory |
| |
Realtime
and archival images of the Sun from SOHO. |
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information about sunspots based on the latest NOAA/USAF Active Region Summary |
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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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