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SpaceWeather.com -- News and information about meteor showers, solar flares, auroras, and near-Earth asteroids
 
Solar wind
speed: 549.6 km/sec
density: 11.5 protons/cm3
more data: ACE, DSCOVR
Updated: Today at 0005 UT
X-ray Solar Flares
6-hr max: B3
2123 UT Apr20
24-hr: B8
0656 UT Apr20
explanation | more data
Updated: Today at: 2359 UT
Daily Sun: 20 Apr 17
Old sunspot AR2644 has returned and been renumbered AR2651. It is crackling with C-class solar flares. Credit: SDO/HMI

Sunspot number: 14
What is the sunspot number?
Updated 20 Apr 2017

Spotless Days
Current Stretch: 0 days
2017 total: 30 days (27%)
2016 total: 32 days (9%)
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 20 Apr 2017


The Radio Sun
10.7 cm flux: 81 sfu
explanation | more data
Updated 20 Apr 2017

Current Auroral Oval:
Switch to: Europe, USA, New Zealand, Antarctica
Credit: NOAA/Ovation
Planetary K-index
Now: Kp= 3 quiet
24-hr max: Kp= 6
storm
explanation | more data
Interplanetary Mag. Field
Btotal: 3.9 nT
Bz: 0.3 nT north
more data: ACE, DSCOVR
Updated: Today at 0005 UT
Coronal Holes: 20 Apr 17

Earth is entering a stream of solar wind flowing from the indicated coronal hole. Credit: NASA/SDO.
Noctilucent Clouds The southern season for noctilucent clouds began on Nov. 17, 2016. Come back to this spot every day to see the "daily daisy" from NASA's AIM spacecraft, which is monitoring the dance of electric-blue around the Antarctic Circle.
Switch view: Ross Ice Shelf, Antarctic Peninsula, East Antarctica, Polar
Updated at: 02-24-2017 17:55:02
SPACE WEATHER
NOAA Forecasts
Updated at: 2017 Apr 20 2200 UTC
FLARE
0-24 hr
24-48 hr
CLASS M
10 %
10 %
CLASS X
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: 2017 Apr 20 2200 UTC
Mid-latitudes
0-24 hr
24-48 hr
ACTIVE
30 %
20 %
MINOR
05 %
05 %
SEVERE
01 %
01 %
High latitudes
0-24 hr
24-48 hr
ACTIVE
15 %
20 %
MINOR
30 %
30 %
SEVERE
35 %
25 %
 
Thursday, Apr. 20, 2017
What's up in space
       
 

Looking for a far-out Mother's Day gift? Find something truly out of this world in the Earth to Sky Store. Space roses, Cosmic Reindeer, Arctic space pendants, and more!

 

SOLAR WIND SPARKS GEOMAGNETIC ACTIVITY: Earth is entering a stream of high-speed solar wind on April 20th, and this is causing G1 to G2-class geomagnetic storms around the poles. NOAA forecasters say there is a 50% chance that these disturbances will continue until April 21st as our planet moves deeper into the stream.

"Last night, northern lights danced across the sky over northern Wyoming," reports Kevin Palmer, who sends this picture from the Bighorn Mountains:

"There were plenty of Lyrid meteors as well," says Palmer.

High-latitude sky watchers should remain alert for auroras tonight as the solar wind continues to blow. Free: Aurora Alerts

Realtime Aurora Photo Gallery

CONTACT BINARY ASTEROID: When mountain-sized asteroid 2014 JO25 flew past Earth on April 19th, it looked like a fast-moving speck of light in backyard telescopes. NASA radars saw much more. The 70-meter antenna at Goldstone CA pinged the asteroid, illuminating it with radio energy as it passed by. The resulting images reveal a peanut-shaped asteroid that rotates about once every five hours:

"The asteroid has a contact binary structure - two lobes connected by a neck-like region," says Shantanu Naidu, a scientist from NASA's Jet Propulsion Laboratory in Pasadena, California, who led the Goldstone observations. "The largest of the asteroid's two lobes is about 2,000 feet (620 meters) across."

These images have a resolution as fine as 25 feet (7.5 meters) per pixel. Additional radar observations are being conducted at both Goldstone and Arecibo on April 20 and 21, and could provide even greater detail. Stay tuned!

Realtime Asteroid Photo Gallery

Realtime Space Weather 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 Spaceweather.com.

On Apr. 20, 2017, 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 April 20, 2017 there were 1798 potentially hazardous asteroids.
Recent & Upcoming Earth-asteroid encounters:
Asteroid
Date(UT)
Miss Distance
Velocity (km/s)
Diameter (m)
2017 GO4
2017-Apr-15
13.8 LD
6
34
2014 UR
2017-Apr-19
18.8 LD
4.4
17
2014 JO25
2017-Apr-19
4.6 LD
33.6
852
2017 GL4
2017-Apr-20
17.5 LD
7.4
22
2017 GM4
2017-Apr-20
13.1 LD
16.6
143
2017 FH101
2017-Apr-24
18.8 LD
9.9
103
2017 FE157
2017-Apr-29
18.6 LD
8.6
64
2015 VD1
2017-May-07
18.2 LD
10.5
34
2012 EC
2017-May-16
19.5 LD
4.5
74
2017 CS
2017-May-29
8 LD
9.1
468
418094
2017-Jun-01
8 LD
23.2
490
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

Readers, thank you for your patience while we continue to develop this new section of Spaceweather.com. We've been working to streamline our data reduction, allowing us to post results from balloon flights much more rapidly, and we have developed a new data product, shown here:

This plot displays radiation measurements not only in the stratosphere, but also at aviation altitudes. Dose rates are expessed as multiples of sea level. For instance, we see that boarding a plane that flies at 25,000 feet exposes passengers to dose rates ~10x higher than sea level. At 40,000 feet, the multiplier is closer to 50x. These measurements are made by our usual cosmic ray payload as it passes through aviation altitudes en route to the stratosphere over California.

What is this all about? 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. Furthermore, there are studies ( #1, #2, #3, #4) linking cosmic rays with cardiac arrhythmias and sudden cardiac death in the general population. Our latest measurements show that cosmic rays are intensifying, with an increase of more than 12% since 2015:


Why are cosmic rays intensifying? The main reason is the sun. Solar storm clouds such as coronal mass ejections (CMEs) sweep aside cosmic rays when they pass by Earth. During Solar Maximum, CMEs are abundant and cosmic rays are held at bay. Now, however, the solar cycle is swinging toward Solar Minimum, allowing cosmic rays to return. Another reason could be the weakening of Earth's magnetic field, which helps protect us from deep-space radiation.

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.

The data points in the graph above correspond to the peak of the Reneger-Pfotzer maximum, which lies about 67,000 feet above central California. When cosmic rays crash into Earth's atmosphere, they produce a spray of secondary particles that is most intense at the entrance to the stratosphere. Physicists Eric Reneger and Georg Pfotzer discovered the maximum using balloons in the 1930s and it is what we are measuring today.

  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
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NOAA 27-Day Space Weather Forecasts
  fun to read, but should be taken with a grain of salt! Forecasts looking ahead more than a few days are often wrong.
Aurora 30 min forecast
  from the NOAA Space Environment Center
Heliophysics
  the underlying science of space weather
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