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<<back forward>> -- News and information about meteor showers, solar flares, auroras, and near-Earth asteroids
Solar wind
speed: 320.0 km/sec
density: 3.1 protons/cm3
explanation | more data
Updated: Today at 2346 UT
X-ray Solar Flares
6-hr max: C1
1656 UT Oct29
24-hr: C1
1506 UT Oct29
explanation | more data
Updated: Today at: 2300 UT
Daily Sun: 29 Oct 15
A new and potentially active sunspot (circled) is emerging over the sun's eastern limg. Credit: SDO/HMI

Sunspot number: 71
What is the sunspot number?
Updated 29 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 29 Oct 2015

The Radio Sun
10.7 cm flux: 112 sfu
explanation | more data
Updated 29 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= 2
explanation | more data
Interplanetary Mag. Field
Btotal: 7.5 nT
Bz: 3.8 nT north
explanation | more data
Updated: Today at 2347 UT
Coronal Holes: 29 Oct 15

High-speed solar wind flowing from this emerging coronal hole will reach Earth on Nov. 3-4. 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 29 2200 UTC
0-24 hr
24-48 hr
25 %
25 %
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 29 2200 UTC
0-24 hr
24-48 hr
25 %
25 %
05 %
05 %
01 %
01 %
High latitudes
0-24 hr
24-48 hr
15 %
15 %
30 %
35 %
35 %
35 %
Thursday, Oct. 29, 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

SOLAR SECTOR BOUNDARY CROSSING: High-latitude auroras are possible on Oct. 29th when Earth crosses through a fold in the heliospheric current sheet. This is called a "solar sector boundary crossing," and NOAA forecasters estimate a 30% chance of polar geomagnetic storms when it occurs. Aurora alerts: text or voice

HALLOWEEN FIREBALLS THIS WEEKEND? Ten years ago, in late Oct. 2005, Earth ran into an unusually dense stream of debris from Comet Encke, source of the annual Taurid meteor shower. The result was a display of bright fireballs widely observed from Oct. 28th through Nov. 10th. Astronomers called them the "Halloween Fireballs," and they looked like this:

Hiroyuki Iida took the picture on Oct. 28, 2005, from Toyama, Japan. To get a sense of the fireball's luminosity, look just above it. That is Sirius, the brightest star in the sky. The fireball was at least as bright.

Astronomer David Asher, who correctly predicted the 2005 "Taurid swarm," thinks Earth might run into another filament of debris from Comet Encke this weekend. If so, the encounter would spark a renewed display of Halloween fireballs. The best time to look is during the hours around midnight when the constellation Taurus is high in the sky. If the shower materializes, observers could see a meteor explode every few hours.

Taurid fireballs come from a swarm of particles bigger than normal comet dust. They're about the size of pebbles or small stones. The rocky swarm moves within the greater Encke dust stream, sometimes hitting Earth, sometimes not. Will this Halloween be a hit? Stay tuned.

Realtime Meteor Photo Gallery

HALLOWEEN ASTEROID: An asteroid the size of a battleship will fly past the Earth-Moon system on Oct. 31st. There's no danger of a collision. Asteroid 2015 TB145 will be 300,000 miles away from Earth at closest approach on Halloween. That's too far for goosebumps, but close enough for a good view. NASA radar astronomers plan to make high-resolution maps of the passing space rock.

At the moment, 2015 TB145 is still a dim speck in the southern constellation Eridanus. Amateur astronomer Marian Urbanik photographed it on Oct. 26th using a remotely controlled 0.43 meter telescope in Siding Springs, Australia:

When Urbanik took the picture, the asteroid was shining like a 16th magnitude star. By the time it reaches the Earth-Moon system on Halloween, it will have brightened 250-fold to 10th magnitude. That's too dim for the naked eye, but an easy target for experienced astronomers with mid-sized backyard telecopes. An article from Sky & Telescope discusses the asteroid's visibility.

2015 TB145 is about 400 meters wide. According to the Minor Planet Center, this is the closest known approach by an object this large until asteroid 1999 AN10 (800 meters wide) approaches Earth at a distance of 238,000 miles in August 2027.

Lance Benner, a radar astronomer at JPL, has raised the intriguing possibility that 2015 TB145 is not an asteroid. "The asteroid's orbit is very oblong with a high inclination to below the plane of the solar system," said Benner. "Such a unique orbit, along with its high encounter velocity -- about 35 kilometers or 22 miles per second -- raises the question of whether it may be some type of comet. If so, then this would be the first time that the Goldstone radar has imaged a comet from such a close distance."

Realtime Space Weather Photo Gallery

LONG RANGE AURORA FORECAST: On Oct. 7th and 8th, a high-speed stream of solar wind hit Earth's magnetic field, sparking strong geomagnetic storms and auroras. On Nov. 2nd - 5th, it could happen again. The same solar wind stream that caused the October storms is set to return during the first week of November. It is flowing from this hole in the sun's atmosphere:

Image credit: NASA/Solar Dynamics Observatory. Oct. 29, 2015.

The dark circled region, called a "coronal hole," is where the sun's magnetic field has opened up, allowing solar wind to escape. The last time this particular coronal hole turned toward Earth, in early October, it lashed our planet's magnetic field with an 800 km/s solar wind stream. Now it is turning toward Earth again. Aurora fans, mark your calendar for the first week of November. You might see something like this. Aurora alerts: text or voice

Realtime Aurora 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

On Oct. 29, 2015, the network reported 15 fireballs.
(11 sporadics, 4 Southern Taurids)

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 29, 2015 there were 1631 potentially hazardous asteroids.
Recent & Upcoming Earth-asteroid encounters:
Miss Distance
2015 UL52
Oct 25
8.3 LD
47 m
2015 TL238
Oct 27
13.3 LD
46 m
2015 UH
Oct 29
9.4 LD
38 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
2008 CM
Dec 29
22.8 LD
1.5 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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