| |
EI2GYB > ASTRO 31.08.21 14:02l 191 Lines 9461 Bytes #999 (0) @ WW
BID : 13943_EI2GYB
Read: GUEST
Subj: Multiple Explosions Reported on Sun's Surface
Path: IW8PGT<IZ3LSV<IQ2LB<IR2UFV<N3HYM<GB7CIP<EI2GYB
Sent: 210831/1158Z 13943@EI2GYB.DGL.IRL.EURO BPQ6.0.22
_ _ _ _
/ \ ___| |_ _ __ ___ | \ | | _____ _____
/ _ \ / __| __| '__/ _ \ | \| |/ _ \ \ /\ / / __|
/ ___ \\__ \ |_| | | (_) | | |\ | __/\ V V /\__ \
/_/ \_\___/\__|_| \___/ |_| \_|\___| \_/\_/ |___/
Multiple Explosions Reported on Sun's Surface; Blasts of Energy Head Towards
Earth:
A series of significant eruptions have helped propel matter and energy into
space from the Sun in the last few days; according to the National Weather
Service's Space Weather Prediction Center (SWPC), some of these blasts
could set the stage for several days of geomagnetic storm conditions on Earth.
The latest SWPC forecasts suggest the possibility of a geomagnetic storm
impact late tonight, again tomorrow, and again around September 2.
Each of these situations could have impacts on Earth and just above it;
they could also trigger the aurora to display in areas more south than
usual in the Northern Hemisphere and more north than usual in the Southern
Hemisphere.
A C3 flare erupted from sunspot region 2859 on the Sun on August 26 and
appears to have sent a solar blast towards the Earth. The SPWC, through
analysis of available imagery from the SOHO/LASCO instrument, confirmed a
partial halo CME took place. It appears this solar explosion set-off a
"solar tsunami".
A solar tsunami, also known as a Moreton Wave or a Moreton-Ramsey Wave,
is the signature of a large-scale solar corona shock wave generated by solar
flares.
Initially spotted in the late 1950's, technology deployed by NASA in
2009 confirmed the presence and the mechanics of such a tsunami.
Unlike a wave of water in the sense of a traditional tsunami, a solar
tsunami is a wave of hot plasma and magnetism roughly 62,000 miles
tall which races through the solar system at speeds of around 560,000 mph.
"Now we know," says Joe Gurman of the Solar Physics Laboratory at NASA's
Goddard Space Flight Center.
"Solar tsunamis are real."
NASA's Solar Terrestrial Relations Observatory (STEREO) confirmed
the presence of a solar tsunami in 2009.
The twin STEREO spacecraft captured the unexpected eruption of sunspot
11012 in February of that year; the blast hurled a billion-ton cloud of
gas into space and sent a tsunami racing along the sun's surface.
STEREO recorded the wave from two positions separated by 90 degrees, g
iving researchers an unprecedented view of the event.
"It was definitely a wave," says Spiros Patsourakos of George Mason
University, lead author of a paper reporting the finding in Astrophysical
Journal Letters.
"Not a wave of water, but a giant wave of hot plasma and magnetism."
The technical name is "fast-mode magnetohydrodynamical wave," or
"MHD wave" for short. The one STEREO saw climbed up about 60,000 miles
high, raced outward at 560,000 mph, and packed as much energy as
2.4 million megatons of TNT.
And now it appears the CME from region 2859 initiated a similar solar
tsunami today.
Two other solar storms were launched towards Earth yesterday.
It will take roughly 24 to 36 hours from each blast to reach Earth.
Scientists are working now to determine what kind, if any, geomagnetic storm
will unfold from this solar tsunami and the two subsequent solar blasts. .
While a an earlier CME impacted the earth early on August 27, setting off
a brilliant aurora show at northern latitudes, a more significant event
could unfold with this solar tsunami and other blasts.
Geomagnetic storms are rated on a 1-5 scale, with 1 being the weakest and
5 having the most potential for damage. Even a G1 geomagnetic storm could
create issues: there could be weak power grid fluctuations and minor
impacts on satellite operations.
Aurora, also known as the "Northern Lights", could be visible at high
latitudes from northern Michigan and Maine to points north.
Impacts and aurora change as the geomagnetic storm scale increase.
Dark regions on the Sun known as coronal holes are one of the main drivers
of space weather now.
According to the Space Weather Prediction Center, coronal holes appear as
dark regions on the Sun because they are cooler than the surrounding plasma
and are open magnetic field lines.
The Sun's outermost part of its atmosphere, which is known as the
corona, is where these dark regions appear.
The solar corona was also one of the main features of the Sun scientists
were most excited to study during the past solar eclipse.
You are able to notice these features in extreme ultraviolet (EUV) and
soft x-ray solar images.
Solar wind is always flowing from the Sun and towards Earth but coronal
holes are known for releasing enhanced solar wind. Coronal holes can develop
anywhere on the sun and are more common during solar minimum.
One solar rotation of the Sun occurs every 27 days and coronal holes
are sometimes able to last several of these.
It is common to see persistent coronal holes at the north and south pole
of the Sun but sometimes they can expand towards the equator of the
Sun resulting in a larger region.
Normally, coronal holes located near the Sun's equator, result in
faster solar wind arriving at Earth.
It is common to see coronal holes produce G1-G2 geomagnetic storming
levels and sometimes on rare occasions, upwards to G3 levels have been met.
NOAA forecasters analyze these features and have to take them into account
during each forecast.
If Earth is experiencing the effects of a coronal hole and a coronal mass
ejection is forecasted to impact Earth, the combined effects could result
in a more significant impact and more intense geomagnetic storming.
Analyzing data from the DSCOVER and ACE satellite is one way forecasters
can tell when the enhanced solar wind from a coronal hole is about to
arrive at Earth. A few things they look for in the data to determine when
the enhanced solar wind is arriving at Earth:
Solar wind speed increases
Temperature increases
Particle density decreases
Interplanetary magnetic field (IMF) strength increases
If you are an aurora chaser or space weather enthusiasts, you'll want to
become familiar with coronal holes.
They will be providing much of our geomagnetic activity going forward and
will remain persistent during solar minimum.
Citizen Scientists should explore Aurorasaurus which allows you to share or
get alerts and images on aurora activity with a community of others
interested in space weather.
While these solar events can help illuminate the sky with stunning aurora,
they can also do considerable harm to electronics, electrical grids, and
satellite and radio communications.
On September 1-2 in 1859, a powerful geomagnetic storm struck Earth during
Solar Cycle 10.
A CME hit the Earth and induced the largest geomagnetic storm on record.
The storm was so intense it created extremely bright, vivid aurora
throughout the planet: people in California thought the sun rose early,
people in the northeastern U.S. could read a newspaper at night from the
aurora's bright light, and people as far south as Hawaii and south-central
Mexico could see the aurora in the sky.
The event severely damaged the limited electrical and communication lines
that existed at that time; telegraph systems around the world failed, with
some telegraph operators reporting they received electric shocks.
A June 2013 study by Lloyd's of London and Atmospheric and Environmental
Research (AER) in the U.S. showed that if the Carrington event happened in
modern times, damages in the U.S. could exceed $2.6 trillion, roughly
15% of the nation's annual GDP.
While typically known for their weather forecasts, the National Oceanic
and Atmospheric Administration (NOAA) and its National Weather Service
(NWS) is also responsible for "space weather."
While there are private companies and other agencies that monitor and
forecast space weather, the official source for alerts and warnings of
the space environment is the Space Weather Prediction Center (SWPC).
The SWPC is located in Boulder, Colorado and is a service center of
the NWS, which is part of NOAA. The Space Weather Prediction Center is
also one of nine National Centers for Environmental Prediction (NCEP) as
they monitor current space weather activity 24/7, 365 days a year.
Right now, the SWPC believes there's a 30% chance of R1/R2 radio blackouts
today and tomorrow.
The SWPC also believes there's a chance of G1 Geomagnetic Storm conditions
on Earth today and tomorrow.
An analysis of the most recent blast isn't yet complete.
The expected impacts today and tomorrow include weak power grid
fluctuations, minor impacts on satellite operations, and the aurora can
be visible at high latitudes, such as northern Michigan and Maine.
Even migratory animals are affected by this space weather and could become
disoriented.
____ __ ____ ___ _ _ ____ ____ ____ ____
( __)( )(___ \ / __)( \/ )( _ \ ( _ \( _ \/ ___)
) _) )( / __/( (_ \ ) / ) _ ( ) _ ( ) _ (\___ \
(____)(__)(____) \___/(__/ (____/ (____/(____/(____/
PART OF THE DONEGAL PACKET RADIO NETWORK
Packet: EI2GYB@EI2GYB.DGL.IRL.EURO
Email: EI2GYB@GMAIL.COM
+------------------------------------------------------------------------------+
Read previous mail | Read next mail
| |
