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SpaceWeather.com -- News and information about meteor showers, solar flares, auroras, and near-Earth asteroids
 
Solar wind
speed: 431.4 km/sec
density: 7.5 protons/cm3
more data: ACE, DSCOVR
Updated: Today at 2253 UT
X-ray Solar Flares
6-hr max: A1
1827 UT Dec17
24-hr: A2
0807 UT Dec17
explanation | more data
Updated: Today at: 2300 UT
Daily Sun: 17 Dec 18
The sun is blank--no sunspots. Credit: SDO/HMI

Sunspot number: 0
What is the sunspot number?
Updated 17 Dec 2018

Spotless Days
Current Stretch: 1 day
2018 total: 207 days (59%)
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 Dec 2018


Thermosphere Climate Index
today: 3.19
x1010 W Cold
Max: 49.4
x1010 W Hot (10/1957)
Min: 2.05
x1010 W Cold (02/2009)
explanation | more data
Updated 17 Dec 2018

The Radio Sun
10.7 cm flux: 70 sfu
explanation | more data
Updated 17 Dec 2018

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: 3.6 nT
Bz: -3.0 nT south
more data: ACE, DSCOVR
Updated: Today at 2253 UT
Coronal Holes: 17 Dec 18

Solar wind flowing from this coronal hole should reach Earth on Dec. 17th, possibly causing minor geomagnetic unrest. Credit: SDO/AIA
Noctilucent Clouds The southern season for noctilucent clouds (NLCs) has begun! NASA's AIM spacecraft is detecting electric blue clouds at the edge of space over Antarctica.
Switch view: Europe, USA, Asia, Polar
Updated at: 12-17-2018 15:55:03
SPACE WEATHER
NOAA Forecasts
Updated at: 2018 Dec 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: 2018 Dec 17 2200 UTC
Mid-latitudes
0-24 hr
24-48 hr
ACTIVE
10 %
20 %
MINOR
01 %
10 %
SEVERE
01 %
01 %
High latitudes
0-24 hr
24-48 hr
ACTIVE
15 %
20 %
MINOR
15 %
25 %
SEVERE
15 %
25 %
 
Monday, Dec. 17, 2018
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!

 

ARCTIC AURORAS: A minor stream of solar wind is buffeting Earth's magnetic field today, Dec. 17th, and this is causing intermittent auroras around the Arctic Circle. "It may be Solar Minimum, and there may be a bright Moon hanging in the sky, but the Northern Lights are still shining strong and bringing a smile to everyone in our small village!" reports Chad Blakley from Abisko National Park in Sweden. "Check our webcam for updates." Free: Aurora Alerts.

WEEKEND COMET FLYBY: Over the weekend, Comet 46P/Wirtanen made history. The green ball of gas wrapped around a nugget of dirty ice flew past Earth only 11.5 million km away--so close that it cracked the top 10 list of comet flybys during the Space Age. During the hours of closest approach, 46P/Wirtanen appeared in the constellation Taurus alongside the Pleiades star cluster:


Michael Jäger took the picture on Dec. 16th from Turmkogel, Austria. "To create the image, I combined 6-minute exposures through red, green and blue filters," says Jäger.

The colors in Jäger's image are remarkable--a striking contrast of green vs. blue.  Wirtanen's green comes from diatomic carbon (C2)--a gaseous substance common in comet atmospheres that glows green in the near-vacuum of space. The Pleiades, on the other hand, appear blue because the stars themselves are that color. Hot and massive, the Seven Sisters shine their blue light into surrounding clouds of gas and dust, which reflect the azure hue.

46P/Wirtanen is receding from Earth now, but it will still be nearby for days to come. The main challenge for observers is not distance, but rather moonlight. The glare of the waxing Moon will dilute the comet's brightness, making it a challenge to see with the unaided eye. Digital cameras and widefield telescopes will have no trouble, however, capturing the comet's exit. It is currently glowing like a big misty star of 4th magnitude near the horns of the Bull:

Got a picture of 46P/Wirtanen? Submit it to Spaceweather.com's Realtime Comet Photo Gallery.

Realtime Comet Photo Gallery

CHRISTMAS GIFTS FROM THE EDGE OF SPACE: So far in 2018, the students of Earth to Sky Calculus have launched 42 space weather balloons to the stratosphere, measuring cosmic rays over 3 continents, 2 hemispheres, and 7 different US states. You can help them pay their helium bill by purchasing a Christmas gift from the edge of space:

Every item in the Earth to Sky Store has flown to the stratosphere alongside an array of cosmic ray sensors. Carried aloft by giant balloons, these unique gifts travel above 99.7% of Earth's atmosphere, experiencing space-like blasts of cosmic rays, extreme cold, and a wild ride parachuting back to Earth after the balloon explodes. Even Amazon doesn't carry items this far out!

Don't forget to enter coupon code "SPACESANTA" at checkout for a 10% holiday discount.

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 Dec. 17, 2018, the network reported 14 fireballs.
(9 sporadics, 2 Quadrantids, 2 sigma Hydrids, 1 Comae Berenicid)

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 December 17, 2018 there were 1936 potentially hazardous asteroids.
Recent & Upcoming Earth-asteroid encounters:
Asteroid
Date(UT)
Miss Distance
Velocity (km/s)
Diameter (m)
2002 XQ90
2018-Dec-11
18.1 LD
11.5
135
2018 XA4
2018-Dec-11
1 LD
12.8
5
2013 VX4
2018-Dec-11
3.5 LD
6.6
65
2018 XM2
2018-Dec-12
14 LD
12.9
31
2018 XT4
2018-Dec-12
14.6 LD
5.1
18
2018 XL1
2018-Dec-12
2.4 LD
6.2
15
2018 XJ1
2018-Dec-13
5.6 LD
6.3
18
2018 XF4
2018-Dec-13
7.6 LD
14.6
34
2018 XZ4
2018-Dec-13
12 LD
10
81
2015 XX169
2018-Dec-13
17 LD
5.8
12
2018 XE2
2018-Dec-14
10.7 LD
21.1
39
2018 XB5
2018-Dec-14
7 LD
15.2
50
2018 XG4
2018-Dec-15
2.7 LD
7.8
11
2018 VO9
2018-Dec-15
2.6 LD
2.9
15
2018 XH1
2018-Dec-15
11.6 LD
6.7
25
2018 XS4
2018-Dec-16
2.8 LD
8.6
32
2018 XR4
2018-Dec-17
5.3 LD
11.4
15
2018 XC4
2018-Dec-21
1.6 LD
7.8
20
2017 XQ60
2018-Dec-21
11.3 LD
15.6
47
163899
2018-Dec-22
7.4 LD
6.2
1232
418849
2018-Dec-23
16.6 LD
17.6
269
2018 XE4
2018-Dec-26
5.4 LD
9.4
18
2014 AD16
2019-Jan-04
12.9 LD
9.4
12
2018 XO4
2019-Jan-06
7.9 LD
4
30
2016 AZ8
2019-Jan-07
11.6 LD
9.1
224
2013 YM2
2019-Jan-09
7.3 LD
4.3
20
2018 XN
2019-Jan-14
11.9 LD
5.6
59
2013 CW32
2019-Jan-29
13.9 LD
16.4
148
2013 RV9
2019-Feb-06
17.9 LD
5.9
68
2017 PV25
2019-Feb-12
7.3 LD
6.1
43
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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