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<<back forward>> -- News and information about meteor showers, solar flares, auroras, and near-Earth asteroids
Solar wind
speed: 457.3 km/sec
density: 2.2 protons/cm3
explanation | more data
Updated: Today at 2348 UT
X-ray Solar Flares
6-hr max: B4
2234 UT Oct25
24-hr: B9
0003 UT Oct25
explanation | more data
Updated: Today at: 2300 UT
Daily Sun: 25 Oct 15
Not one of these sunspots poses a threat for strong flares. Solar activity is low. Credit: SDO/HMI

Sunspot number: 74
What is the sunspot number?
Updated 25 Oct 2015

Spotless Days
Current Stretch: 0 days
2015 total: 0 days (0%)

2014 total: 1 day (<1%)
2013 total: 0 days (0%)
2012 total: 0 days (0%)
2011 total: 2 days (<1%)
2010 total: 51 days (14%)
2009 total: 260 days (71%)

Updated 25 Oct 2015

The Radio Sun
10.7 cm flux: 106 sfu
explanation | more data
Updated 25 Oct 2015

Current Auroral Oval:
Switch to: Europe, USA, New Zealand, Antarctica
Credit: NOAA/Ovation
Planetary K-index
Now: Kp= 1 quiet
24-hr max: Kp= 3
explanation | more data
Interplanetary Mag. Field
Btotal: 8.5 nT
Bz: 1.7 nT north
explanation | more data
Updated: Today at 2348 UT
Coronal Holes: 25 Oct 15

There are no large coronal holes on the Earthside of the sun. Credit: SDO/AIA.
Noctilucent Clouds The northern season for NLCs is finished. According to NASA's AIM spacecraft, the last clouds were observed over Greenland on Aug. 27th. Now the waiting begins for the southern season expected to begin in November.
Switch view: Europe, USA, Asia, Polar
Updated at: 09-01-2015 09:00:00
NOAA Forecasts
Updated at: 2015 Oct 25 2200 UTC
0-24 hr
24-48 hr
20 %
20 %
01 %
01 %
Geomagnetic Storms:
Probabilities for significant disturbances in Earth's magnetic field are given for three activity levels: active, minor storm, severe storm
Updated at: 2015 Oct 25 2200 UTC
0-24 hr
24-48 hr
20 %
10 %
05 %
01 %
01 %
01 %
High latitudes
0-24 hr
24-48 hr
20 %
15 %
25 %
15 %
25 %
10 %
Sunday, Oct. 25, 2015
What's up in space

Marianne's Heaven On Earth Aurora Chaser Tours invites you to join them in their quest to find and photograph the Aurora Borealis. Experience the winter wonderland in the Tromsø Area.

Chase the Light Tours

RARE BLUE STARTER: We all know what comes out of the bottom of thunderstorms: lightning bolts. But on Oct. 20th, Thomas Ashcraft of New Mexico saw something coming out of the top. "I captured a form of a transient luminous event called a 'blue starter' shooting up from the top of a thunderstorm cloud," he says. "Blue starters are rarely captured from ground level and there are hardly any specimens on the internet."

Lightning scientist Oscar van der Velde explains this phenomenon: "A blue starter is an electric streamer discharge coming out of the top of a thundercloud, fanning out and reaching up to the stratosphere as high as 26 km altitude. First reported by UAF scientists Wescott and Sentman in 1995/1996, they were found to be different from blue jets, which reach 35-40 km height."

"Since then, there have been very few reports of blue starters," continues van der Velde. "It seems that unusual physical circumstances may be required to produce them. Also, geometry can prevent people from seeing blue starters when a cloud is nearby because the underbody of the cloud can block their view. At larger distances the blue/violet light does not make it to the observer due to scattering."

Blue starters and blue jets are cousins of sprites, another form of exotic lightning that shoots up instead of down. Sprites, however, are more frequently observed. Check them out in the realtime photo gallery:

Realtime Sprite Photo Gallery

CME IMPACT SPARKS NO STORMS: Arriving earlier than expected, a coronal mass ejection (CME) hit Earth's magnetic field on Oct. 24th at approximately 1900 UT. NASA's ACE spacecraft, located at the L1 point 1.5 million km upstream from Earth, detected the CME's leading edge about a half hour before it reached Earth:

Solar wind speeds abruptly jumped to more than 500 km/s as the CME passed by. The shockwave rattled Earth's magnetic field and caused electrical currents to flow through the ground of Norway's Lofoten islands: data. However, that's about all that happened. A full-fledged geomagnetic storm did not erupt, and few auroras have been reported. Why was the CME so ineffective? Its internal magnetic field did not connect to Earth's magnetic field; the mismatch mitigated the CME's impact. Aurora alerts: text or voice

Realtime Aurora Photo Gallery

MORNING PLANET SHOW: Set your alarm for dawn. Venus, Jupiter and Mars are gathering for a three-way close encounter in the early morning sky. Yesterday, Kouji Ohnishi woke up early and photographed the convergence from Iiyama, Nagano, Japan. He calls this composition Reverie in Autumn:

"I could see the planets even through deep fog," says Ohnishi. "It was a wonderful morning."

The next five mornings will be equally wonderful. From Oct. 25th to Oct. 29th Venus, Jupiter and Mars will fit together inside a circle only 5o wide (sky maps: #1, #2, #3, #4, #5). Super-bright Venus and Jupiter are visible even after the black pre-dawn sky turns cobalt blue. Once you find them, you will have little trouble locating the dimmer red planet Mars. Enjoy the show!

Realtime Space Weather Photo Gallery

  All Sky Fireball Network
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

On Oct. 25, 2015, the network reported 22 fireballs.
(15 sporadics, 6 Orionids, 1 epsilon Geminid)

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]

  Near Earth Asteroids
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 October 25, 2015 there were potentially hazardous asteroids.
Recent & Upcoming Earth-asteroid encounters:
Miss Distance
2015 TZ143
Oct 22
4.2 LD
26 m
2015 UM52
Oct 22
0.3 LD
12 m
2015 UL52
Oct 25
8.3 LD
48 m
2015 TL238
Oct 27
13.3 LD
47 m
2015 UH
Oct 29
9.5 LD
42 m
2015 TB145
Oct 31
1.3 LD
470 m
2015 TD179
Nov 4
10.6 LD
57 m
2005 UL5
Nov 20
5.9 LD
390 m
2003 EB50
Nov 29
48.8 LD
2.2 km
2007 BG29
Dec 1
54.1 LD
1.1 km
1998 WT24
Dec 11
10.9 LD
1.1 km
2011 YD29
Dec 24
9.7 LD
24 m
2003 SD220
Dec 24
28.4 LD
1.8 km
Notes: LD means "Lunar Distance." 1 LD = 384,401 km, the distance between Earth and the Moon. 1 LD also equals 0.00256 AU. MAG is the visual magnitude of the asteroid on the date of closest approach.
  Cosmic Rays in the Atmosphere
Situation Report -- Oct. 20, 2015 Stratospheric Radiation (+37o N)
Cosmic ray levels are elevated (+5.8% above the Space Age median). The trend is flat. Cosmic ray levels have increased +0% in the past month.
Sept. 06: 4.14 uSv/hr (414 uRad/hr)
Sept. 12: 4.09 uSv/hr (409 uRad/hr)
Sept. 23: 4.12 uSv/hr (412 uRad/hr)
Sept. 25: 4.16 uSv/hr (416 uRad/hr)
Sept. 27: 4.13 uSv/hr (413 uRad/hr)
Oct. 11: 4.02 uSv/hr (402 uRad/hr)
These measurements are based on regular space weather balloon flights: learn more.

RADS ON A PLANE: and the students of Earth to Sky Calculus regularly fly balloons to the stratosphere to measure cosmic rays. For the past six months, May through Oct. 2015, they have been taking their radiation sensors onboard commercial airplanes, too. The chart below summarizes their measurements on 18 different airplanes flying back and forth across the continental United States.

The points on the graph indicate the dose rate of cosmic rays inside the airplanes compared to sea level. For instance, the dose rate for flights that cruised at 40,000+ feet was more than 50x the dose rate on the ground below. No wonder the International Commission on Radiological Protection (ICRP) classifies pilots as occupational radiation workers.

Cosmic rays come from deep space. They are high energy particles accelerated toward Earth by distant explosions such as supernovas and colliding neutron stars. Astronauts aren't the only ones who have to think about them; flyers do, too. Cosmic rays penetrate deep inside Earth's atmosphere where airplanes travel every day.

This type of radiation is modulated by solar activity. Solar storms and CMEs tend to sweep aside cosmic rays, making it more difficult for cosmic rays to reach Earth. Low solar activity, on the other hand, allows an extra dose of cosmic rays to reach our planet. This is important because forecasters expect solar activity to drop sharply in the years ahead as we approach a new Solar Minimum. Cosmic rays are poised to increase accordingly.

The plot, above, tells us what is "normal" in 2015. How will it change as the solar cycle wanes? Stay tuned for regular updates.

  Essential web links
NOAA Space Weather Prediction Center
  The official U.S. government space weather bureau
Atmospheric Optics
  The first place to look for information about sundogs, pillars, rainbows and related phenomena.
Solar Dynamics Observatory
  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
Solar and Heliospheric Observatory
  Realtime and archival images of the Sun from SOHO.
Daily Sunspot Summaries
  from the NOAA Space Environment Center
  the underlying science of space weather
Columbia Northern High School
  Web-based high school science course with free enrollment
  more links...
©2015 All rights reserved. This site is penned daily by Dr. Tony Phillips.
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