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Solar wind
speed: 367.4 km/sec
density: 3.4 protons/cm3
explanation | more data
Updated: Today at 2348 UT
X-ray Solar Flares
6-hr max: C1
1927 UT Apr24
24-hr: C2
0843 UT Apr24
explanation | more data
Updated: Today at: 2300 UT
Daily Sun: 24 Apr 15
Not one of the sunspots on the Earthside of the sun is actively flaring. Credit: SDO/HMI

Sunspot number: 110
What is the sunspot number?
Updated 24 Apr 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 24 Apr 2015

The Radio Sun
10.7 cm flux: 141 sfu
explanation | more data
Updated 24 Apr 2015

Current Auroral Oval:
Switch to: Europe, USA, New Zealand, Antarctica
Credit: NOAA/Ovation
Planetary K-index
Now: Kp= 0 quiet
24-hr max: Kp= 3
explanation | more data
Interplanetary Mag. Field
Btotal: 4.0 nT
Bz: 0.8 nT north
explanation | more data
Updated: Today at 2349 UT
Coronal Holes: 24 Apr 15

There are no large coronal holes on the Earthside of the sun. Credit: SDO/AIA.
Noctilucent Clouds The southern season for NLCs has come to an end. The last clouds were observed by NASA's AIM spacecraft on Feb. 20, 2015. Now attention shifts to the northern hemisphere, where the first clouds of 2015 should appear in mid-May.
Switch view: Ross Ice Shelf, Antarctic Penninsula, East Antarctica, Polar
Updated at: 02-28-2015 02:55:03
NOAA Forecasts
Updated at: 2015 Apr 24 2200 UTC
0-24 hr
24-48 hr
10 %
10 %
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 Apr 24 2200 UTC
0-24 hr
24-48 hr
30 %
15 %
05 %
05 %
01 %
01 %
High latitudes
0-24 hr
24-48 hr
15 %
15 %
30 %
25 %
35 %
20 %
Friday, Apr. 24, 2015
What's up in space

Come to Tromsø and share Marianne's passion for rural photography: invites you to experience "Heaven on Earth" with an aurora, fjord, fishing, whale watching, photography or sightseeing tour.

Chase the Light Tours

SOLAR SECTOR BOUNDARY CROSSING: High-latitude auroras are possible on April 25th 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, voice.

SPECTACULAR PROMINENCE: A magnificent filament of magnetism is rotating over the northeastern limb of the sun. Amateur astronomer Jett Aguilar sends this picture from Quezon City, the Philippines:


"I was lucky to image this beautiful caterpillar-like structure through a break in the clouds," says Aguilar. That's some caterpillar: As the inset picture of Earth shows, the prominence is large enough to swallow our planet more than 50 times over.

This is a type of prominence more commonly called a "hedgerow prominence." Hot glowing plasma inside the structure is held aloft by unstable solar magnetic fields. NASA and Japanese space telescopes have taken high resolution images of of similar prominences and seen some amazing things such as (1) tadpole-shaped plumes that float up from the base of the prominence; (2) narrow streams of plasma that descend from the top like waterfalls; and (3) swirls and vortices that resemble van Gogh's Starry Night.

Got a solar telescope? Take a look!

SpaceWeather Realtime Photo Gallery

VOLCANIC LIGHTNING: For the first time in more than 42 years, the Calbuco volcano in southern Chile has erupted. Two blasts in 24 hours on April 22nd sent plumes of ash and volcanic gases shooting at least 50,000 feet high, well into the altitudes where planes fly. One of the eruptions occured at night and put on a spectacular display of volcanic lightning:

Researchers have long known that volcanic eruptions produce strong lightning. Findings published in a 2012 Eos article reveal that the largest volcanic storms can rival massive supercell thunderstorms in the American midwest. But why? Volcanic lightning is not well understood.

Lightning is nature's way of correcting an imbalance of electric charge. In ordinary thunderstorms, one part of a thundercloud becomes positively charged, and another part becomes negatively charged. This charge comes from collisions between particles: e.g., droplets of water and crystals of ice rub together, creating static electricity in much the same way as woolen socks rubbed against carpet. Lightning arcs between charge-separated regions.

Something similar must be happening inside volcanic plumes. One hypothesis holds that catapulting magma bubbles or volcanic ash are themselves electrically charged, and by their motion create charge-separated areas. Another possibility is that particles of volcanic ash collide with each other and become charged through triboelectric rubbing. In short, no one knows. It is a beautiful and terrifying mystery.

Stay tuned for more images as the eruption of Calbuco continues.

Realtime Space Weather Photo Gallery

SPACE YEAST MAKES SPACE BREAD: Thought experiment: Suppose you flew a packet of baker's yeast high above Earth's surface, to the edge of space itself, and exposed the microbes to a blast of cosmic rays. Then you made some bread. How would it taste? "Delicious," reports Eileen Weingram of Highland Lakes, New Jersey, who actually did the experiment:

On March 17th, during the strongest geomagnetic storm of the current solar cycle, the students of Earth to Sky Calculus flew a Space Weather Buoy to the stratosphere. Along with radiation detectors and other sensors, the payload carried packets of brewer's and baker's yeast. En route to the stratosphere, the microbes experienced temperatures as low as -63 C and cosmic ray doses 40x Earth-normal.

To support the students' research, Eileen Weingram bought a packet of the baker's yeast. "It made a huge loaf of bread," she says. "Very yummy."

If this story whets your appetite, you can bake some "space bread" of your own. Packets of yeast are still available for only $49.95. Contact Dr. Tony Phillips to place your order--and let the baking begin! All sales support high altitude balloon flights to measure the effect of solar storms on Earth's atmosphere.

Realtime Meteor Photo Gallery

Realtime Aurora Photo Gallery

Realtime Comet 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 Apr. 24, 2015, the network reported 12 fireballs.
(6 sporadics, 6 April Lyrids)

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 24, 2015 there were potentially hazardous asteroids.
Recent & Upcoming Earth-asteroid encounters:
Miss Distance
2015 GY12
Apr 19
13.7 LD
31 m
2015 HE1
Apr 21
3.3 LD
17 m
2015 HD1
Apr 21
0.2 LD
15 m
2015 HW10
Apr 23
9.7 LD
32 m
2015 HQ11
Apr 25
1.3 LD
16 m
2015 HE10
Apr 25
8 LD
24 m
2015 GB14
Apr 28
9 LD
37 m
2015 HD10
Apr 29
1.6 LD
17 m
2015 HS11
May 1
7.1 LD
15 m
5381 Sekhmet
May 17
62.8 LD
2.1 km
2015 HT9
May 25
12.2 LD
24 m
2005 XL80
Jun 4
38.1 LD
1.0 km
2012 XB112
Jun 11
10.1 LD
2 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.
  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
Space Weather Alerts
  more links...
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