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SpaceWeather.com -- News and information about meteor showers, solar flares, auroras, and near-Earth asteroids
 
Solar wind
speed: 328.0 km/sec
density: 7.7 protons/cm3
more data: ACE, DSCOVR
Updated: Today at 2351 UT
X-ray Solar Flares
6-hr max: A2
1949 UT Apr17
24-hr: A2
1012 UT Apr17
explanation | more data
Updated: Today at: 2300 UT
Daily Sun: 17 Apr 19
Sunspot AR2738 is quiet and poses no threat for strong solar flares. Credit: SDO/HMI

Sunspot number: 11
What is the sunspot number?
Updated 17 Apr 2019

Spotless Days
Current Stretch: 0 days
2019 total: 62 days (59%)
2018 total: 221 days (61%)
2017 total: 104 days (28%)
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%)
2008 total: 268 days (73%)
2007 total: 152 days (42%)
2006 total: 70 days (19%)

Updated 17 Apr 2019


Thermosphere Climate Index
today: 4.37
x1010 W Cold
Max: 49.4
x1010 W Hot (10/1957)
Min: 2.05
x1010 W Cold (02/2009)
explanation | more data
Updated 17 Apr 2019

The Radio Sun
10.7 cm flux: 74 sfu
explanation | more data
Updated 17 Apr 2019

Current Auroral Oval:
Switch to: Europe, USA, New Zealand, Antarctica
Credit: NOAA/Ovation
Planetary K-index
Now: Kp= 2 quiet
24-hr max: Kp= 2
quiet
explanation | more data
Interplanetary Mag. Field
Btotal: 3.9 nT
Bz: 3.6 nT north
more data: ACE, DSCOVR
Updated: Today at 2349 UT
Coronal Holes: 17 Apr 19


Solar wind flowing from this northern coronal hole could graze Earth's magnetic field on April 19-20, causing polar geomagnetic unrest.
Credit: SDO/AIA

Noctilucent Clouds The northern season for noctilicent clouds is little more than a month away. The electric-blue clouds circling the north pole should return in mid- to late May. .
Switch view: Europe, USA, Asia, Polar
Updated at: 03-02-2019 16:55:03
SPACE WEATHER
NOAA Forecasts
Updated at: 2019 Apr 17 2200 UTC
FLARE
0-24 hr
24-48 hr
CLASS M
01 %
01 %
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: 2019 Apr 17 2200 UTC
Mid-latitudes
0-24 hr
24-48 hr
ACTIVE
15 %
10 %
MINOR
01 %
05 %
SEVERE
01 %
01 %
High latitudes
0-24 hr
24-48 hr
ACTIVE
15 %
15 %
MINOR
20 %
20 %
SEVERE
20 %
20 %
 
Wednesday, Apr. 17, 2019
What's up in space
       
 

Lights Over Lapland has a brand-new website full of exciting adventures in Abisko National Park, Sweden! Take a look at our aurora activities and book your once-in-a-lifetime trip with us today!

 

A NEW SUNSPOT: A new sunspot is growing in the sun's northern hemisphere. Provisionally numbered AR2739, the bipolar region has a magnetic polarity that identifies it as a member of old Solar Cycle 24. Old-cycle sunspots rarely produce strong flares, so the chance of flares remains low even as the sunspot number increases with the emergence of AR2739. Free: SWx Newsletter.

NEUTRONS OVER THE USA: Want to experience space weather? Just step onboard an airplane. At typical cruising altitudes, cosmic rays from deep space penetrate the hulls of commercial jetliners, dosing passengers with levels of radiation comparable to dental X-rays. To measure this radiation, Spaceweather.com and the students of Earth to Sky Calculus have been flying cosmic ray sensors onboard airplanes over 5 continents. Our latest results show something potentially interesting about the continental USA.


Above: Neutrons detected during a flight from Portland to DC on April 9,2019.

On April 9th and 11th we flew neutron bubble chambers from Portland, Oregon, to Washington DC and back again. In the photo, above, each bubble was created by a cosmic ray neutron. Why measure neutrons? Studies show that neutrons can be ten times more effective at causing biological damage compared to X-rays and gamma-rays in the same energy range. Neutrons are so effective, they are used for cancer therapy, killing tumors better than other forms of radiation.

During these flights, we measured more than 20 uGy of neutron radiation--the whole body equivalent of two panoramic dental X-rays. That's significant, but no worse than a trip to the dentist's office. 

The interesting thing is how these values compare to other places we've flown. Our neutron chambers have traveled more than 40,000 miles on 14 flights over North America, South America, Asia, Europe, and Africa, all with typical altitudes near 35,000 feet. So far, neutron dose rates have been highest in one place: the continental USA (CONUS).

In this histogram, flights over CONUS are color-coded red. Other parts of the world are blue. The distribution's red tail shows the tendency of US flights to "out-neutron" international flights. This may be a result of small-number statistics. If so, the anomaly could disappear as more data are added. Our neutron survey is continuing, so stay tuned.

Free: Spaceweather.com Newsletter

MOTHER'S DAY IS LESS THAN ONE MONTH AWAY: Nothing says "I Love You" like a heart-shaped pendant from the edge of space. On Dec. 31st, the students of Earth to Sky Calculus flew an array of cosmic ray sensors to the stratosphere onboard a giant helium balloon. This pendant went along for the ride:

You can have it for $129.95. The students are selling these pendants as a fund-raiser for their cosmic ray monitoring program--and they make great Mother's Day gifts. All proceeds support atmospheric radiation measurements and hands-on STEM education.

Each pendant comes with a greeting card showing the jewelry in flight and telling the story of its journey to the stratosphere and back again. Mom-satisfaction guaranteed.

Far Out Gifts: Earth to Sky Store
All sales support hands-on STEM education


Realtime Space Weather Photo Gallery

Realtime Aurora 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. 17, 2019, 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 17, 2019 there were 1967 potentially hazardous asteroids.
Recent & Upcoming Earth-asteroid encounters:
Asteroid
Date(UT)
Miss Distance
Velocity (km/s)
Diameter (m)
2019 GN20
2019-Apr-12
1 LD
14.8
18
2019 GU20
2019-Apr-12
6.2 LD
16.8
30
2019 FB3
2019-Apr-12
11.9 LD
14.2
45
2019 GC4
2019-Apr-12
5.1 LD
33.5
37
2019 GL4
2019-Apr-12
14.5 LD
13.2
84
2019 GQ1
2019-Apr-12
13.4 LD
12.7
39
2019 GN
2019-Apr-13
1.7 LD
11.9
14
2019 GO4
2019-Apr-13
5 LD
23.5
31
2019 FO1
2019-Apr-13
14.3 LD
9.7
29
2019 FH1
2019-Apr-13
18 LD
3.8
31
2019 GN4
2019-Apr-13
7.4 LD
18.4
40
2019 GW20
2019-Apr-16
3.4 LD
13.6
11
2019 GR20
2019-Apr-16
11 LD
9.7
17
2019 GC6
2019-Apr-18
0.6 LD
5.6
18
2012 XO134
2019-Apr-18
14.8 LD
11
56
2019 FN2
2019-Apr-18
4.1 LD
7.7
66
522684
2019-Apr-19
19 LD
11.5
214
2019 GZ3
2019-Apr-20
10.1 LD
14.2
23
2019 GM
2019-Apr-21
19.4 LD
10.4
35
2019 FV2
2019-Apr-22
15.6 LD
2.3
33
2019 GM4
2019-Apr-23
9.1 LD
8.4
72
2019 GF1
2019-Apr-27
4.7 LD
1.9
11
2019 GX5
2019-Apr-28
7.2 LD
10.7
26
2018 KK1
2019-May-05
13.9 LD
13.9
71
2017 RC
2019-May-09
14.5 LD
10.6
9
2008 HS3
2019-May-09
14.6 LD
5.3
162
2018 VX8
2019-May-12
6.2 LD
15.5
118
2019 GT1
2019-May-17
6.1 LD
3.9
36
2012 KT12
2019-May-18
3.3 LD
3.9
20
2015 KQ18
2019-May-25
10.7 LD
13.1
30
66391
2019-May-25
13.5 LD
21.5
1780
2003 LH
2019-May-28
15.6 LD
7.4
32
2011 HP
2019-May-30
12.3 LD
8.4
135
2014 MF18
2019-Jun-06
8.8 LD
3
22
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

SOMETHING NEW! We have developed a new predictive model of aviation radiation. It's called E-RAD--short for Empirical RADiation model. We are constantly flying radiation sensors onboard airplanes over the US and and around the world, so far collecting more than 22,000 gps-tagged radiation measurements. Using this unique dataset, we can predict the dosage on any flight over the USA with an error no worse than 15%.

E-RAD lets us do something new: Every day we monitor approximately 1400 flights criss-crossing the 10 busiest routes in the continental USA. Typically, this includes more than 80,000 passengers per day. E-RAD calculates the radiation exposure for every single flight.

The Hot Flights Table is a daily summary of these calculations. It shows the 5 charter flights with the highest dose rates; the 5 commercial flights with the highest dose rates; 5 commercial flights with near-average dose rates; and the 5 commercial flights with the lowest dose rates. Passengers typically experience dose rates that are 20 to 70 times higher than natural radiation at sea level.

To measure radiation on airplanes, we use the same sensors we fly to the stratosphere onboard Earth to Sky Calculus cosmic ray balloons: neutron bubble chambers and X-ray/gamma-ray Geiger tubes sensitive to energies between 10 keV and 20 MeV. These energies span the range of medical X-ray machines and airport security scanners.

Column definitions: (1) The flight number; (2) The maximum dose rate during the flight, expressed in units of natural radiation at sea level; (3) The maximum altitude of the plane in feet above sea level; (4) Departure city; (5) Arrival city; (6) Duration of the flight.

SPACE WEATHER BALLOON DATA: 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 18% since 2015:

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.

En route to the stratosphere, our sensors also pass through aviation altitudes:

In this plot, 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.

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.

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.

  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
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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