By Spaceweather.com, 02/23/2017

THE SOLAR WIND HAS ARRIVED: As predicted, today Earth is entering a fast-moving stream of solar wind. NOAA forecasters estimate a 60% chance of polar geomagnetic storms as the wind speed quickens. Arctic sky watchers should be alert for auroras on on Feb. 23rd and 24th. Free: Aurora Alerts

AURORA ROCKET LAUNCH: On Feb. 22nd, shortly after midnight, bright green auroras erupted over Alaska’s Poker Flat Research Range. Researchers from Dartmouth College promptly launched a rocket into the glowing maelstrom. Photographer Marketa Murray of Fairbanks captured the event in a perfectly-timed self-portrait:

 

“We tuned into the Poker Flat Research Range radio for a heads-up that the rocket was about to launch,” explains Murray. “The picture shows both stages of the Black Brant IX sounding rocket burning for the ionosphere.”

The goal of the mission, named ISINGLASS (Ionospheric Structuring: In Situ and Groundbased Low Altitude Studies) is to decipher the mysterious shapes of the aurora borealis. Some auroras look like flames, others like swirls, ripples or curtains. The rocket was designed to scatter an array of sensors into the auroral zone, mapping the particles and fields underlying these forms.

“Auroras are the last step of a chain of processes connecting the solar wind to the atmosphere,” says Dr. Kristina Lynch of Dartmouth, the mission’s principal investigator. “We are seeking to understand what structure in these visible signatures can tell us about the electrodynamics of processes higher up.” 

“It was a beautiful launch with an extensive set of collaborative ground based data, and will make a great study,” she says.

Ultimately, the results could allow researchers to look up at the sky and, based on little more than the shapes they see, predict conditions at the edge of space. Was the mission a success? Stay tuned for updates from the launch team.

Realtime Aurora Photo Gallery

POLLEN CORONAS: In parts of New Mexico, people are starting to sneeze–and see colorful rings around the sun. The two experiences are related.  They are both manifestations of pollen.  Photographer Harald Edens of Magdalena NM explains: “Every year in late February or early March, the juniper trees in New Mexico produce pollen. The pollen particles are all quite small and uniform in size; as a result, they scatter sunlight and produce colored rings around the sun.”

 

“Today’s pollen corona was by far the most intense I have observed in New Mexico over the past 14 years, with up to four orders (repeated color bands) readily visible to the unaided eye,” Edens continues. “The pollen is so abundant that it appears like smoke coming off the juniper trees whenever there is a gust of wind, or a bird lands in a tree.”

Readers, if you see a pollen corona, here’s something else to look for: The colorful rings are not always circular.  Pollens are non-spherical; many have air sacs to help carry them in the wind. These align the grains to give beautiful elliptical coronas with bright spots.

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 Feb. 23, 2017, the network reported 8 fireballs.
(8 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 February 23, 2017 there were 1775 potentially hazardous asteroids.

Recent & Upcoming Earth-asteroid encounters:

Asteroid

Date(UT)

Miss Distance

Size

2017 DB

Feb 20

1.8 LD

17 m

2017 DV15

Feb 21

8.8 LD

40 m

2017 DD

Feb 23

14.6 LD

95 m

2017 BY93

Feb 23

2.4 LD

102 m

1992 FE

Feb 24

13.1 LD

275 m

2017 CP1

Feb 24

3.6 LD

52 m

1998 QK56

Feb 24

53 LD

1.2 km

2017 BM123

Feb 27

12.4 LD

80 m

2012 DR32

Mar 2

2.7 LD

52 m

1998 SL36

Mar 16

8.3 LD

390 m

2015 TC25

Mar 26

7.6 LD

6 m

2003 BD44

Apr 18

21.7 LD

1.9 km

2014 JO25

Apr 19

4.6 LD

1.0 km

1999 CU3

Apr 19

63.7 LD

1.9 km

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.

 

Current Conditions

Solar wind
speed: 533.0 km/sec
density: 8.2 protons/cm3
more data: ACE, DSCOVR
Updated: Today at 1818 UT

X-ray Solar Flares
6-hr max: B2 1428 UT Feb23
24-hr: B4 1054 UT Feb23
explanation | more data
Updated: Today at: 1800 UT

 

Daily Sun: 23 Feb 17

 

Sunspot AR2638 might be (slightly) more potent than previously thought. Yesterday it produced a minor C4-class solar flare: SDO image. Credit: SDO/HMI

 

Sunspot number: 17
What is the sunspot number?
Updated 23 Feb 2017

Spotless Days
Current Stretch: 0 days
2017 total: 11 days (22%)
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 23 Feb 2017

The Radio Sun
10.7 cm flux: 83 sfu
explanation | more data
Updated 23 Feb 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= 3 quiet
explanation | more data

Interplanetary Mag. Field
Btotal: 12.2 nT
Bz: 2.8 nT north
more data: ACE, DSCOVR
Updated: Today at 1816 UT

 

Coronal Holes: 23 Feb 17

Solar wind flowing from the indicated coronal hole should reach Earth on Feb. 23-24. 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: 02-23-2017 16:55:03

 

SPACE WEATHER
NOAA Forecasts

 

Updated at: 2017 Feb 22 2200 UTC

FLARE

0-24 hr

24-48 hr

CLASS M

05 %

05 %

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 Feb 22 2200 UTC

Mid-latitudes

0-24 hr

24-48 hr

ACTIVE

35 %

30 %

MINOR

25 %

10 %

SEVERE

05 %

01 %

High latitudes

0-24 hr

24-48 hr

ACTIVE

10 %

15 %

MINOR

20 %

25 %

SEVERE

60 %

40 %