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Solar wind
speed: 353.4 km/sec
density: 3.5 protons/cm3
explanation | more data
Updated: Today at 2351 UT
X-ray Solar Flares
6-hr max: C7
2021 UT Sep28
24-hr: M7
1458 UT Sep28
explanation | more data
Updated: Today at: 2300 UT
Daily Sun: 28 Sep 15
Sunspot AR2422 has a 'beta-gamma-delta' magnetic field that harbors energy for X-class solar flares. Credit: SDO/HMI

Sunspot number: 154
What is the sunspot number?
Updated 28 Sep 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 28 Sep 2015


The Radio Sun
10.7 cm flux: 128 sfu
explanation | more data
Updated 28 Sep 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= 2
quiet
explanation | more data
Interplanetary Mag. Field
Btotal: 4.1 nT
Bz: 3.8 nT south
explanation | more data
Updated: Today at 2350 UT
Coronal Holes: 28 Sep 15

There are no large coronal holes on the Earhside 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
SPACE WEATHER
NOAA Forecasts
Updated at: 2015 Sep 28 2200 UTC
FLARE
0-24 hr
24-48 hr
CLASS M
70 %
70 %
CLASS X
25 %
25 %
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 Sep 28 2200 UTC
Mid-latitudes
0-24 hr
24-48 hr
ACTIVE
05 %
10 %
MINOR
01 %
05 %
SEVERE
01 %
01 %
High latitudes
0-24 hr
24-48 hr
ACTIVE
15 %
20 %
MINOR
15 %
25 %
SEVERE
10 %
15 %
 
Monday, Sep. 28, 2015
What's up in space
 

On Sept. 27th, the Harvest Moon will pass through the shadow of Earth, turning the lunar disk a lovely shade of celestial red. Catch it live on the Internet, courtesy of the Coca-Cola Space Science Center in Columbus, Georgia.

 
Eclipse Webcast

SOLAR FLARE AND RADIO BLACKOUT: Today, Sept. 28th at 1458 UT, a strong M7-class solar flare erupted in the magnetic canopy of sunspot AR2422. Extreme UV radiation from the flare ionized the top of Earth's atmosphere and caused a brief low-frequency radio blackout over South America and the Atlantic ocean: blackout map. AR2422 has an unstable 'beta-gamma-delta' magnetic field that could erupt again at any moment. NOAA forecasters estimate a 40% chance of additional M-class solar flares and a 5% chance of X-flares during the next 24 hours. Solar flare alerts: text or voice

DARK LUNAR ECLIPSE (UPDATED): On Sunday night, Sept. 27th, the supermoon passed through the shadow of Earth, producing a total lunar eclipse visible from the Americas, Europe, Africa and parts of Asia. "It was one of the darkest lunar eclipses I have ever seen," reports Kevin R. Witman, who sends this picture from Cochranville, Pennsylvania:

Other observers (see the gallery) also remarked on the darker hue of this lunar eclipse, compared to others in recent years. What caused the change? Atmospheric scientist Richard Keen of the University of Colorado offers one reason: "Supermoon eclipses should be a bit darker. Because of its closeness to Earth, a supermoon passes deeper into the shadow of our planet."

Working independently, Steve Albers of NOAA and Helio Vital of REA/Brazil have suggested another reason: aerosols in the atmosphere.

"Earth's stratosphere is no longer completely clean of volcanic ashes," says Vital. "In fact, lingering aerosols from the explosion of Calbuco, five months ago, may be to blame for that excessive darkening."

Calbuco is a volcano in Chile. After it erupted in April 2015, colorful sunsets were observed around the southern hemisphere for months. Recently, Albers has noted an increase in purple and yellow sunsets around his home town, Boulder CO, and elsewhere. These are telltale colors of volcanic exhaust.

"A thin veneer of aerosols from Calbuco may have now spread to the northern hemisphere," Albers says. "In addition, we could be seeing the effects of residual smoke from forest fires at high altitudes, or the general increase in sulfate pollution that has been documented on a global basis."

Richard Keen, who is a leading expert on volcanic aerosols and lunar eclipses, says "the Sept. 27th eclipse was about 0.5 magnitudes darker than expected for a clear stratosphere. A slight layer of aerosols in the upper troposphere/lower stratosphere might explain this. Also, the Moon passed through the southern part of Earth's shadow, so southern hemisphere aerosols (such as those produced by Calbuco) would have greater effect."

Keen says that he is still "crunching the numbers," and we may have more information soon...

Realtime Eclipse Photo Gallery

COSMIC RAYS IN THE ATMOSPHERE: Once a week, and sometimes more often, Spaceweather.com and the students of Earth to Sky Calculus fly "space weather balloons" to the stratosphere. These balloons are equipped with radiation sensors that detect cosmic rays, a form of space weather important to people on Earth. Cosmic rays can alter the chemistry of the upper atmosphere, seed clouds, spark exotic forms of lightning, and penetrate commercial airplanes. This last point is of special interest to the traveling public. Our measurements show that someone flying back and forth across the continental USA, just once, can absorb as much ionizing radiation as 2 to 5 dental X-rays. From now on we will be present the results of our regular weekly balloon flights in a new and dedicated section of our web site: Cosmic Rays in the Atmosphere. Scroll down to find it.

As an example of the kind of data you'll see, here is a radiation profile from our Sept. 23rd flight:

As the balloon ascends toward the stratosphere, radiation levels increase rapidly. By the time the payload reaches aviation altitudes (25,000 ft to 45,000 ft), dose rates are as much as 50 times higher than sea level. According to the Sept. 23rd measurements, a plane flying at 45,000 feet is exposed to 278 uRads/hr. At that rate, a passenger would absorb about one dental X-ray's worth of radiation in 5 hours.

Radiation levels peak at the entrance to the stratosphere in a broad region called the "Pfotzer Maximum." This peak is named after physicist George Pfotzer who discovered it using balloons and Geiger tubes in the 1930s. Radiation levels there are nearly 100x sea level.

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, so the data are of practical interest to humans.

Realtime Space Weather Photo Gallery


Realtime Aurora Photo Gallery

Realtime Sprite Photo Gallery


  Cosmic Rays in the Atmosphere
Situation Report -- Sept. 28, 2015 Stratospheric Radiation (+37o N)
Cosmic ray levels are elevated (+6% above the Space Age median). The trend is flat. Cosmic ray levels have increased +0% in the past month.
Sept. 06: 414 uRad/hr
Sept. 12: 409 uRad/hr
Sept. 23: 412 uRad/hr
Sept. 25: 416 uRad/hr
These measurements are based on space weather balloon flights, described below.

Introduction: Once a week, and sometimes more often, Spaceweather.com and the students of Earth to Sky Calculus fly "space weather balloons" to the stratosphere. These balloons are equipped with radiation sensors that detect cosmic rays, a form of space weather important to people on Earth. Cosmic rays can alter the chemistry of the upper atmosphere, seed clouds, spark exotic forms of lightning, and penetrate commercial airplanes. This last point is of special interest to the traveling public. Our measurements show that someone flying back and forth across the continental USA, just once, can absorb as much ionizing radiation as 2 to 5 dental X-rays. From now on we will be present the results of our regular weekly balloon flights in this section of our web site. Here is the radiation profile from our Sept. 23rd flight:

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. In the plot, dose rates are given in microRads per hour (uRads/hr). According to the Sept. 23rd measurements, a plane flying at 45,000 feet is exposed to 278 uRads/hr. At that rate, a passenger would absorb about one dental X-ray's worth of radiation in 5 hours.

Stay tuned for improvements to this section in the days and weeks ahead as we develop a glossary and better plain language strategies for communicating this information. Suggestions are welcomed.

  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 Spaceweather.com.

On Sep. 28, 2015, the network reported 9 fireballs.
(9 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]

  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 September 28, 2015 there were potentially hazardous asteroids.
Recent & Upcoming Earth-asteroid encounters:
Asteroid
Date(UT)
Miss Distance
Size
2015 SK7
Sep 22
0.07 LD
8 m
2015 SU
Sep 23
14.8 LD
36 m
2015 SV6
Sep 25
2.3 LD
13 m
2015 RU36
Sep 26
14.7 LD
39 m
2015 ST6
Sep 29
10.3 LD
58 m
2015 SZ2
Sep 30
1.3 LD
36 m
2015 RF36
Sep 30
14.6 LD
102 m
2015 SO2
Sep 30
14.3 LD
70 m
2000 SM10
Oct 2
11.7 LD
65 m
2015 SR
Oct 3
14.7 LD
54 m
2000 FL10
Oct 10
65.7 LD
1.9 km
2011 QD48
Oct 17
67.5 LD
1.0 km
2014 UR
Oct 18
3.8 LD
21 m
2011 SE97
Oct 18
11.9 LD
50 m
2001 UY4
Oct 21
58.2 LD
1.0 km
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
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.
  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.
STEREO
  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
Heliophysics
  the underlying science of space weather
Columbia Northern High School
  Web-based high school science course with free enrollment
   
   
  more links...
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