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SpaceWeather.com -- News and information about meteor showers, solar flares, auroras, and near-Earth asteroids
 
Solar wind
speed: 406.7 km/sec
density: 3.0 protons/cm3
explanation | more data
Updated: Today at 2348 UT
X-ray Solar Flares
6-hr max: B5
1800 UT Apr18
24-hr: M6
0029 UT Apr18
explanation | more data
Updated: Today at: 2300 UT
Daily Sun: 18 Apr 16
Big sunspot AR2529 erupted during the early hours of April 18th, producing a M6.7-class solar flare. Credit: SDO/HMI

Sunspot number: 35
What is the sunspot number?
Updated 18 Apr 2016

Spotless Days
Current Stretch: 0 days
2016 total: 0 days (0%)
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 18 Apr 2016


The Radio Sun
10.7 cm flux: 102 sfu
explanation | more data
Updated 18 Apr 2016

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
quiet
explanation | more data
Interplanetary Mag. Field
Btotal: 5.6 nT
Bz: 2.5 nT north
explanation | more data
Updated: Today at 2348 UT
Coronal Holes: 18 Apr 16
Solar wind flowing from the indicated coronal hole should reach Earth on April 19. Credit: SDO/AIA.
Noctilucent Clouds The southern season for noctilucent clouds began on Dec. 13, 2015. It is expected to end in late February or March 2016.
Switch view: Ross Ice Shelf, Antarctic Peninsula, East Antarctica, Polar
Updated at: 02-12-2016 16:55:02
SPACE WEATHER
NOAA Forecasts
Updated at: 2016 Apr 18 2200 UTC
FLARE
0-24 hr
24-48 hr
CLASS M
20 %
10 %
CLASS X
05 %
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: 2016 Apr 18 2200 UTC
Mid-latitudes
0-24 hr
24-48 hr
ACTIVE
35 %
15 %
MINOR
10 %
10 %
SEVERE
01 %
01 %
High latitudes
0-24 hr
24-48 hr
ACTIVE
15 %
15 %
MINOR
30 %
20 %
SEVERE
45 %
25 %
 
Monday, Apr. 18, 2016
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

SOLAR FLARE UPDATE: NOAA forecasters say that a CME hurled into space by today's M6.7-flare might deliver a glancing blow to Earth's magnetic field on April 20th. High-latitude sky watchers should be alert for auroras during a possible G1-class geomagnetic storm. Aurora alerts: text or voice

BIG SUNSPOT ERUPTS: Surprise! Quiet sunspot AR2529 isn't so quiet, after all. The heart-shaped active region erupted on April 18th (00:39 UT), producing a strong M6.7-class solar flare. NASA's Solar Dynamics Observatory recorded the flare's extreme ultraviolet flash:

A pulse of UV radiation from the flare ionized the top of Earth's atmosphere. This, in turn, disrupted shortwave radio communications over the daylit side of our planet. Mariners, aviators, and ham radio operators around the Pacific Ocean may have noticed fading signals at frequencies below ~15 MHz. A NOAA blackout map shows the frequencies and territories affected.

More M-class flares are possible in the days ahead. AR2529 has developed a 'beta-gamma' magnetic field that harbors plenty of energy for this kind of explosion. Although the sunspot is no longer directly facing Earth, it can still affect our planet by causing radio blackouts and glancing-blow CMEs. Stay tuned. Solar flare alerts: text or voice

Realtime Space Weather Photo Gallery

A SOLAR WIND STREAM IS COMING: Geomagnetic activity should remain low throughout the weekend. Conditions could shift to an active state late Monday, April 18th, when Earth enters a stream of high-speed solar wind. The solar wind is flowing out of this coronal hole on the sun:

Coronal holes are places in the sun's upper atmosphere where magnetic fields peel back, allowing solar wind to escape. In the image, above, from NASA's Solar Dynamics Observatory, the flow of solar wind is traced by arrows. The escaping material is now nearing Earth.

The incoming solar wind stream is filled with positive-polarity magnetic fields. This means it might not do a good job sparking auroras. Positive polarity magnetic fields from the sun do not easily link to Earth's planetary magnetic field. As a result, their effect on our magnetosphere is often muted. Stay tuned for updates.

Realtime Aurora Photo Gallery

SPACE ROSES: Last week, the students of Earth to Sky Calculus launched a daring experiment. Daring for the flowers, that is. A bouquet of live roses flew to the edge of space onboard a helium balloon to find out if if they could survive the trip. The answer, apparently, is "yes." Here are the blossoms floating 35.4 km (116,000 feet) above Earth's surface:

.

The roses were hitchikers on a cosmic ray payload, which went to the stratosphere to monitor increasing levels of space radiation. En route to the top, the flowers were exposed to a dose of cosmic rays 100x Earth normal, air pressures as low as 0.2% of sea level, and temperatures as low as -63 C. Three hours later, the roses parachuted back to Earth and landed ... in Death Valley! Talk about a rough trip.

And now we come to Mother's Day. These flowers, which were pressed after recovery, are available as gifts. Buy one here and give mom something truly out of this world on May 8th. Each pressed rose comes with a unique card showing the flowers in flight. All proceeds support the student space weather research of Earth to Sky Calculus.


Solar Eclipse Photo Gallery


Realtime Comet Photo Gallery
[More about Comet 252P: brightness measurements, 3D orbit, orbital elements]

  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 Apr. 18, 2016, the network reported 11 fireballs.
(11 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 April 18, 2016 there were potentially hazardous asteroids.
Recent & Upcoming Earth-asteroid encounters:
Asteroid
Date(UT)
Miss Distance
Size
2016 FL13
Apr 15
9.7 LD
36 m
2008 HU4
Apr 16
4.9 LD
10 m
2016 GM2
Apr 16
12.6 LD
41 m
2016 FY12
Apr 17
5.8 LD
24 m
2016 GP221
Apr 18
1.5 LD
28 m
2016 FN13
Apr 19
13.9 LD
13 m
2016 GB222
Apr 21
4.4 LD
21 m
2016 GC1
Apr 21
8.8 LD
21 m
2016 GZ220
Apr 21
10.1 LD
24 m
2016 GV221
Apr 21
8.6 LD
41 m
2016 HA
Apr 22
6.5 LD
26 m
2016 GD207
Apr 22
4.4 LD
29 m
2016 FH12
Apr 23
7.9 LD
21 m
2016 GC222
Apr 24
14 LD
33 m
2016 FY3
Apr 25
6.4 LD
310 m
2001 VG5
Apr 28
52.4 LD
1.8 km
2014 US115
May 1
9.4 LD
52 m
2008 TZ3
May 5
13.1 LD
355 m
2014 JG55
May 8
7.6 LD
7 m
2016 GS2
May 18
3.4 LD
109 m
2009 DL46
May 24
6.2 LD
215 m
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. 30, 2015 Stratospheric Radiation (+37o N)
Cosmic ray levels are elevated (+6.1% 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)
Oct. 22: 4.11 uSv/hr (411 uRad/hr)
These measurements are based on regular space weather balloon flights: learn more.

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 surprisingly "down to Earth" form of space weather. Cosmic rays can seed clouds, trigger lightning, and penetrate commercial airplanes. 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. For example, here is the data from a flight on Oct. 22, 2015:

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 22th measurements, a plane flying at 45,000 feet is exposed to 2.79 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.

  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
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