Space Weather Update: 11/22/2015
By Spaceweather.com, 11/22/2015
SLIGHT UPTICK IN SOLAR ACTIVITY: Solar activity has been very low for more than a week. Growing sunspot AR2454 is breaking the quiet–but only a little. The active region is crackling with minor C-class solar flares. The explosions could intensify if the sunspot continues to grow. Solar flare alerts: text or voice
FLY ME TO THE MOON: Observers of America’s space program have often lamented that the International Space Station cannot go to the Moon. On Nov. 21st, it looks like it finally made the trip. Dennis Simmons sends this picture from Brisbane, Qld, Australia:
Unfortunately, only looks like the ISS has re-traced the steps of Apollo. The giant spaceship is still in Earth orbit. It did, however, pass in front of the Moon as seen by observers in parts of Australia.
“The transit lasted just 0.49 seconds,” says Simmons, who used a video camera to record the split-second passage. “This is a composite of video frames taken through a C9.25 telescope.”
Elsewhere in Brisbane, astrophotographer Tom Harradine also took a spectacular picture of the transit. “I caught the ISS passing by the crater Copernicus,” he says.
At the time of the transit, the ISS was 400 km from Earth and almost 400 thousandkm from the Moon. So it still has a ways to go. One day, perhaps, those distances will be reversed, and the lunar transits we see today will be a preview of things to come.
AURORAS, FOR NO PARTICULAR REASON: Nov. 21st was a day of quiet space weather. There were no intense solar flares, no CMEs, and no geomagnetic storms. The auroras appeared anyway. Liselotte Kahns saw them over Sweden’s Abisko National Park:
“Despite the extremely low level of solar activity, Abisko’s clear sky demonstrated a nice aurora display tonight,” says Kahns. “[It’s] a good illustration of why this place is rated as one of the best places on Earth to see auroras.”
Indeed, it is not unusual for auroras to appear over Abisko even when the forecast calls for no magnetic activity. Aurora tour guides and photographers naturally gravitate toward the Park because of its frequently-green skies. The reason is Abisko’s location beneath Earth’s persistent auroral oval. A gentle rain of solar wind electrons, guided to Earth by our planet’s curved magnetic field, creates a polar ringof Northern Lights that intersects the latitude of Abisko, more often than not. Browse the realtime gallery for more sightings:
TRANSCONTINENTAL SPACE WEATHER BALLOON FLIGHT: On Nov. 21st, the students of Earth to Sky Calculus, in collaboration with Spaceweather.com and the University of New Hampshire, launched a pair of space weather balloons from opposite sides of the USA. Using cell phones to conduct a transcontinental countdown, they released the balloons at the same moment from California and New Hampshire:
Flying simultaneously, the balloons ascended to the stratosphere, sampling X-rays and gamma-rays at altitudes of interest to aviation, space tourism, and climate science. The goal of the experiment is to investigate a curious difference in radiation, which the group discovered during a previous transcontinental flight in July 2015. During the summer, radiation levels in the stratosphere above New Hampshire were more than 25% higher than California, a surprisingly wide gap considering the relatively small difference in latitude between the two launch sites. The Nov. 21st flight will confirm and expand upon the findings from July.
Update: Both payloads have parachuted back to Earth. The New Hampshire payload landed in Maine, and has since been recovered from the branches of a tall tree. The California payload landed in the Saline Valley, a desert area not far from Death Valley National Park. It will be recovered on Nov. 22nd. Stay tuned for results from the flight.
WAITING FOR NOCTILUCENT CLOUDS: Summer is the season for noctilucent clouds (NLCs)–icy wisps of electric-blue that float at the edge of space. This means NLCs should be appearing soon over Antarctica, where summer is nigh. NASA’sAIM spacecraft has started monitoring the south pole, but so far the maps are blank:
“Since AIM was launched, previous seasons in the southern hemisphere have started anywhere from Nov. 17th to Dec. 16th,” says Cora Randall, a member of the AIM science team and the chair of the Department of Atmospheric and Oceanic Sciences at the University of Colorado. “It seems to depend on when winds in the southern stratosphere shift to their summerly state. This year the polar vortex in the lower stratosphere is very large, which suggests that the season will have a late start.”
Researchers will be watching with interest. Last year’s season for southern NLCs was unusual. The clouds varied strangely and they completely disappeared for a few weeks after the solstice when they are normally most abundant.
What does this mean? Research shows that NLCs are a sensitive indicator of long-range teleconnections in Earth’s atmosphere, which link weather and climate across hemispheres. The strange behavior of noctilucent clouds in 2014-2015 could be a sign of previously unknown linkages.
Are these linkages still at work? Will the southern NLCs of 2015-2016 “misbehave” again? Answers will be revealed in data from the AIM spacecraft, which has been studying NLCs from Earth orbit since 2007. You can monitor the latest images right here on Spaceweather.com.
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 Nov. 21, 2015, the network reported 76 fireballs.
(32 sporadics, 29 Leonids, 11 Northern Taurids, 2 November omega Orionids, 1 omicron Eridanid, 1 alpha Monocerotid)
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 November 22, 2015 there were 1634 potentially hazardous asteroids.
Recent & Upcoming Earth-asteroid encounters:Asteroid
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
Situation Report — Oct. 30, 2015Stratospheric Radiation (+37o N)
Cosmic ray levels are elevated(+6.1% above the Space Age median). The trend is flat. Cosmic ray levels have increased +0% in the past month.
Sept. 06: 4.14 uSv/hr (414 uRad/hr)
Sept. 12: 4.09 uSv/hr (409 uRad/hr)
Sept. 23: 4.12 uSv/hr (412 uRad/hr)
Sept. 25: 4.16 uSv/hr (416 uRad/hr)
Sept. 27: 4.13 uSv/hr (413 uRad/hr)
Oct. 11: 4.02 uSv/hr (402 uRad/hr)
Oct. 22: 4.11 uSv/hr (411 uRad/hr)
These measurements are based on regular space weather balloon flights: learn more.
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. Our measurements show that someone flying back and forth across the continental USA, just once, can absorb as much ionizing radiation as 2 to 5 dental X-rays. Here is the data from our latest flight, Oct. 22nd:
Radiation levels peak at the entrance to the stratosphere in a broad region called the “Pfotzer Maximum.” This peak is named after physicist George Pfotzer who discovered it using balloons and Geiger tubes in the 1930s. Radiation levels there are more than 80x sea level.
Note that the bottom of the Pfotzer Maximim is near 55,000 ft. This means that some high-flying aircraft are not far from the zone of maximum radiation. Indeed, according to the Oct 22th measurements, a plane flying at 45,000 feet is exposed to 2.79 uSv/hr. At that rate, a passenger would absorb about one dental X-ray’s worth of radiation in about 5 hours.
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.
speed: 330.6 km/sec
density: 3.5 protons/cm3
explanation | more data
Updated: Today at 1407 UTX-ray Solar Flares
6-hr max: C2 1023 UT Nov22
24-hr: C5 0538 UT Nov22
explanation | more data
Updated: Today at: 1400 UTDaily Sun: 21 Nov 15Growing sunspot AR2454 is crackling with minor C-class solar flares. Credit: SDO/HMI
Sunspot number: 59
What is the sunspot number?
Updated 21 Nov 2015
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 21 Nov 2015
Current Auroral Oval:
Switch to: Europe, USA, New Zealand, Antarctica
Credit: NOAA/OvationPlanetary K-index
Now: Kp= 0 quiet
24-hr max: Kp= 1 quiet
explanation | more data
Interplanetary Mag. Field
Btotal: 3.6 nT
Bz: 2.6 nT north
explanation | more data
Updated: Today at 1408 UTCoronal Holes: 21 Nov 15
There are no large coronal holes on the Earthside of the sun. Credit: SDO/AIA.Noctilucent Clouds The northern season for NLCs is finished. According to NASA’s AIM spacecraft, the last clouds were observed over Greenland on Aug. 27th. Now the waiting begins for the southern season expected to begin in November.
Switch view: Ross Ice Shelf, Antarctic Peninsula, East Antarctica, PolarUpdated at: 11-21-2015 17:55:02
Updated at: 2015 Nov 21 2200 UTC
Probabilities for significant disturbances in Earth’s magnetic field are given for three activity levels: active, minor storm, severe stormUpdated at: 2015 Nov 21 2200 UTCMid-latitudes