The ISS passed through the “Big Dipper” August 23, 2012. Photo by Chris Christie.
There was a bright, beautiful pass by the International Space Station the night of August 23, 2012. Alerted by CAA member Jay Reynolds, fellow member Chris Christie set up his camera and got an excellent shot of the station’s arc. That night’s pass was of the “fading” type; the space station rises above the horizon reflecting sunlight and, due to the Sun’s angle and the projection of Earth’s shadow into space, crosses into that shadow while still very high in the sky. The path of the ISS, as viewed from Northeastern Ohio, took it right through the Big Dipper asterism. Light pollution provides color above the horizon. Christie’s photo data: Canon EOS Rebel T3: ISO 800, f/3.5, 18mm, 55-second exposure started at 9:39 PM.
At the bottom edge of the setting Sun, here, there may be a green flash.
The “green flash” is not a new Marvel Comics superhero but a subtle and interesting phenomenon sometimes seen just before sunrise or just after sunset; a green-colored ray or spot is seen just above the horizon. CAA member Jay Reynolds observed and photographed an occurrence of the green flash on Aug. 6 from Kelleys Island.
“Unfortunately, as these predictions go, the possibility of seeing it was well announced by TV meteorologists…” said Reynolds, “but this occurrence was subtle and not easily detectable.” In other words, many looked for the flash but few saw it!
“In photo number one, there is a possible green flash visible at the bottom of the sun. It is unfortunate that the shot is overexposed to the point of saturation” he said. “Suzie Dills deserves the credit for detecting it during the photo review.”
Green flash is visible just after sunset August 6, 2012. Enlarge to best see color.
“Photo number two is the best of the main sequence,” said Reynolds of his images. Viewed in a larger size, the green coloration is easily visible.
“It still was an outstanding Lake Erie Sunset shared by all!”
The first two full-resolution images of the Martian surface from the Navigation cameras on NASA’s Curiosity rover. These are full-resolution images, 1024 by 1024 pixels in size. Image credit: NASA/JPL-Caltech
These are the first two full-resolution images of the Martian surface from the Navigation cameras on NASA’s Curiosity rover, which are located on the rover’s “head” or mast. The rim of Gale Crater can be seen in the distance beyond the pebbly ground.
The topography of the rim is very mountainous due to erosion. The ground seen in the middle shows low-relief scarps and plains. The foreground shows two distinct zones of excavation likely carved out by blasts from the rover’s descent stage thrusters.
Wednesday, Aug. 8, the team deployed the 3.6 foot-tall (1.1-meter) camera mast, activated and gathered surface radiation data from the rover’s Radiation Assessment Detector and concluded testing of the rover’s high-gain antenna.
Curiosity carries 10 science instruments with a total mass 15 times as large as the science payloads on NASA’s Mars rovers Spirit and Opportunity. Some of the tools, such as a laser-firing instrument for checking rocks’ elemental composition from a distance, are the first of their kind on Mars. Curiosity will use a drill and scoop, which are located at the end of its robotic arm, to gather soil and powdered samples of rock interiors, then sieve and parcel out these samples into the rover’s analytical laboratory instruments.
To handle this science toolkit, Curiosity is twice as long and five times as heavy as Spirit or Opportunity. The Gale Crater landing site places the rover within driving distance of layers of the crater’s interior mountain. Observations from orbit have identified clay and sulfate minerals in the lower layers, indicating a wet history.
Just below center-left, is AR1520, as seen from Northeastern Ohio on July 12 at 6:18 PM EDT.
Dominating the face of our Sun, this week, has been an enormous group of sunspots including those designated AR1520. The active Sun has been very interesting to watch, of late, as the dark spots rotated over the star’s limb and towards the center of its disk, facing Earth. Hydrogen-alpha observers have also been rewarded with good numbers of prominences spouting into the blackness of space. Forecasters stated AR1520 had great potential for flare activity and on Thursday, July 12, the forecast was fulfilled — just as the sunspot was aimed directly at Earth.
According to SpaceWeather.com, “Big sunspot AR1520 unleashed an X1.4-class solar flare on July 12th at 1653 UT. Because this sunspot is directly facing Earth, everything about the blast was geoeffective. For one thing, it hurled a coronal mass ejection (CME) directly toward our planet. According to a forecast track prepared by analysts at the Goddard Space Weather Lab, the CME will hit Earth on July 14th around 10:20 UT (+/- 7 hours) and could spark strong geomagnetic storms. Sky watchers should be alert for auroras this weekend.”
NASA’s orbital solar observatories, of course, captured images of the flare as it erupted. Very rarely is any individual human observer watching when the detonation occurs but one can get lucky. CAA Vice-President Mike Williams was very lucky. “I was looking at the spot {with my personal solar telescope} when it popped,” he said. “Wow what a sight!”
As so often seems the case, weather forecasts for the weekend include plenty of clouds to interfere with the view. Still, aurora fans should stay alert to active displays and the potential for clear skies; it could be a good show!
UPDATE: The CME impacted the Earth’s magnetic field at ~ 1800 UT or 2:00 PM EDT, July 14.
Photo above: The Sun with prominent AR1520 accompanied by smaller sunspots. Canon EOS 50D: ISO 400, f/11, 1/1000 sec., 400mm telephoto lens with AstroZap white light filter, 6:18 PM, July 12, 2012 — “just before the clouds rolled in,” according to photographer James Guilford.
