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SpaceWeather.com -- News and information about meteor showers, solar flares, auroras, and near-Earth asteroids
 
Solar wind
speed: 436.9 km/sec
density: 3.8 protons/cm3
explanation | more data
Updated: Today at 2348 UT
X-ray Solar Flares
6-hr max: C7
1756 UT Oct21
24-hr: C7
1756 UT Oct21
explanation | more data
Updated: Today at: 2300 UT
Daily Sun: 21 Oct 15
Sunspot AR2436 has a 'beta-delta' magnetic field that harbors energy for C-class solar flares. Credit: SDO/HMI

Sunspot number: 77
What is the sunspot number?
Updated 21 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 21 Oct 2015


The Radio Sun
10.7 cm flux: 123 sfu
explanation | more data
Updated 21 Oct 2015

Current Auroral Oval:
Switch to: Europe, USA, New Zealand, Antarctica
Credit: NOAA/Ovation
Planetary K-index
Now: Kp= 2 quiet
24-hr max: Kp= 4
unsettled
explanation | more data
Interplanetary Mag. Field
Btotal: 4.3 nT
Bz: 0.9 nT north
explanation | more data
Updated: Today at 2348 UT
Coronal Holes: 21 Oct 15

Solar wind flowing from this minor coronal hole should reach Earth on Oct. 22-23. 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 Oct 21 2200 UTC
FLARE
0-24 hr
24-48 hr
CLASS M
45 %
45 %
CLASS X
05 %
05 %
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 21 2200 UTC
Mid-latitudes
0-24 hr
24-48 hr
ACTIVE
20 %
10 %
MINOR
05 %
01 %
SEVERE
01 %
01 %
High latitudes
0-24 hr
24-48 hr
ACTIVE
20 %
15 %
MINOR
25 %
15 %
SEVERE
25 %
15 %
 
Wednesday, Oct. 21, 2015
What's up in space
 

Marianne's Heaven On Earth Aurora Chaser Tours Chasethelighttours.co.uk 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

MINOR STORM WARNING: High-latitude sky watchers should be alert for auroras after nightfall on Wednesday. Earth is entering a stream of solar wind, and this could spark minor (G1-class) geomagnetic storms on Oct. 21-22. Aurora alerts: text or voice

ORIONID METEOR SHOWER STILL ACTIVE: This morning, listeners of Space Weather Radio heard a lot of radar echoes--a sign that the Orionid meteor shower is active on Oct. 21st. Specks of dust from Halley's Comet are flying through Earth's atmosphere, reflecting radar signals and disintegrating in bright flashes of light. Last night, NASA's network of all-sky meteor cameras detected 19 Orionid fireballs over the USA. This one exploded over Chickamauga,Tennessee:

Fireballs are meteors at least as bright as the planet Venus (magnitude -4). They are just the tip of the iceberg. For every bright fireball picked up by a NASA camera, there are dozens of fainter Orionids visible to the naked eye from dark sky sites. The best time to look is during the dark hours before sunrise on Thursday the 22nd: sky map.

Extra: The Canadian Meteor Orbit Radar (CMOR) is detecting a continued stream of meteoroids emerging from the constellation Orion on Oct. 21st. The pink "hot spot" in this radar sky map shows the shower's radiant:

These data from CMOR further confirm that the shower is still active.

Realtime Meteor Photo Gallery

SPACE WEATHER BALLOONING--LATEST RESULTS: Approximately 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 radiation sensors that detect cosmic rays, a form of space weather important to people on Earth. Cosmic rays 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.

Here is the data from our latest flight, Oct. 11th:

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 more than 80x sea level.

Note that the bottom of the Pfotzer Maximim is near 55,000 ft. This means that some high-flying aircraft are not far from the zone of maximum radiation. Indeed, according to the Oct 11th measurements, a plane flying at 45,000 feet is exposed to 2.77 uSv/hr. At that rate, a passenger would absorb about one dental X-ray's worth of radiation in about 5 hours.

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.

Our next flight is scheduled for tomorrow, Oct.22nd. Stay tuned!

Realtime Space Weather Photo Gallery


Realtime Aurora Photo Gallery


Realtime Eclipse Photo Gallery


Realtime Sprite 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 Spaceweather.com.

On Oct. 21, 2015, the network reported 63 fireballs.
(42 sporadics, 19 Orionids, 2 Leonis Minorids)

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 21, 2015 there were potentially hazardous asteroids.
Recent & Upcoming Earth-asteroid encounters:
Asteroid
Date(UT)
Miss Distance
Size
2015 TC179
Oct 14
12.3 LD
26 m
2015 TG144
Oct 16
13.3 LD
33 m
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
2015 TD144
Oct 20
11.7 LD
130 m
2001 UY4
Oct 21
58.2 LD
1.0 km
2015 TZ143
Oct 22
4.2 LD
26 m
2015 TL238
Oct 27
13.3 LD
52 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
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: Spaceweather.com 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.
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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