Earth's Aurora Erupts With Powerful X-Ray Display
Although its job is to search for powerful energies emanated by distant cosmic objects, a space observatory recently turned its eye toward Earth and saw our home planet's aurora glowing brightly with powerful X-rays.
Although its job is to search for powerful energies emanated by distant cosmic objects, ESA's INTEGRAL space observatory recently turned its eye toward Earth and saw our home planet's aurora glowing brightly with powerful X-rays.
The animation below is made from data acquired by INTEGRAL's IBIS/ISGRI instrument on Nov. 10, 2015. Although Earth isn't itself visible its position and northern rotational pole is noted by the light blue lines as the data were captured across 8-minute intervals. The X-ray emissions from auroras dancing above Russia, Canada, and Greenland are visible as bright red, yellow, and white flashes.
Coincidentally these same auroral displays were also captured from low-Earth orbit by NASA astronaut Scott Kelly. The photo below was shared on Twitter by Kelly to mark one of the 15 sunrises ISS astronauts experience every day, as well as the completion of day 228 of his year-long mission aboard Station.
Auroras are the result of charged particles streaming out from the sun getting caught up in Earth's magnetic field and "funneled" back down toward the poles, from where the magnetic field lines originate. When these particles collide with atoms in the atmosphere radiation is emitted across a wide range of the electromagnetic spectrum, including visible light.
Launched Oct. 17, 2002, ESA's International Gamma-Ray Astrophysics Laboratory (INTEGRAL) is a 4-ton, 16-foot (5-meter) -tall spacecraft designed to observe the universe in high-energy wavelengths, specifically gamma rays from supermassive black holes but also in X-ray and select optical wavelengths. It orbits Earth at distances ranging from 6,200 miles (10,000 km) to 87,000 (140,000 km), outside the most harmful and interfering energy of the radiation belts.
On rare occasions INTEGRAL is aimed toward Earth to block out the background field and allow scientists to calibrate the instruments. It just so happened that this time Earth put on an X-ray performance of its own.
"Auroras are transient, and cannot be predicted on the timeframe that satellite observations are planned, so it was certainly an unexpected observation," said INTEGRAL Project Scientist Erik Kuulkers. "Although the original background X-ray measurements didn't go quite to plan this time, it was exciting to capture such intense auroral activity by chance."
INTEGRAL is the result of an international collaboration between ESA and the U.S., Russia, the Czech Republic, and Poland, and includes instruments from research teams in Italy, France, Germany, Denmark, and Spain. Learn more about the INTEGRAL mission here.
X-rays from Earth’s aurora captured by ESA’s INTEGRAL on Nov. 10, 2015.
In recent weeks, the crew on board the International Space Station have been treated to some awesome views of space weather in action. The sun, which has been spluttering out some small to mid-sized flares and coronal mass ejections recently, frequently injects charged particles into our planet's magnetosphere. After being channeled toward high latitudes by Earth's magnetic field, this solar plasma impacts our atmosphere, erupting into a stunning auroral display.
This view from the space station was captured by one of the crew and shows the multicolored streamers of an aurora over the Southern Hemisphere -- known as the Aurora Australis. The different colors correspond to different gases in the atmosphere becoming energized by the solar plasma impacting the atmosphere at high altitudes.
Russian cosmonaut Oleg Artemyev
of a diffuse aurora over Earth out of one of the space station's windows. The orbiting outpost's solar panels can be seen to the left.
With the space station's robotic Canadarm 2 folded outside the space station, NASA astronaut Reid Wiseman
A bright green aurora snakes over the atmosphere below the space station. Green aurorae are caused by lower altitude oxygen atoms in our atmosphere being energized by solar wind electrons.
A burst of beautiful green and red aurorae were spotted on Aug. 19 and NASA astronaut Reid Wiseman
: "Never in my wildest dreams did I imagine this."
The nighttime hemisphere of the Earth is almost dark apart from the ghostly glow of a green aurora.
Often resembling a curtain swaying in the wind, aurorae are strikingly dynamic. They morph into a variety of shapes depending on the quantity of solar plasma hitting the atmosphere and the orientation of the magnetic field.
on Aug. 27, a stunning, curved aurora cuts across the limb of the Earth.
Looking down at Earth during a solar storm, ESA astronaut Alexander Gerst
, "This is what we see looking down while being inside an aurora."
The moon sets into an "glowing ocean of green",
. Two Soyuz spacecraft can be seen in the foreground docked to the space station.