APOD and General Astronomy Discussion Forum
https://asterisk.apod.com/
What is the wave-like structure in this photograph besides the Milky Way as seen from a remote location in northern Chile? Did TWAN photographer capture a UFO, a squadron of hidden alien spaceships?!
More about the photo: viewing the sky from very high altitude locations is an amazing experience. Stars become sharp and dazzling with less atmospheric turbulence and extinction affected on their light. Located in Lauca National Park at Chile's far north on the border with Bolivia, volcanoes Pomerape (6282 m) and Parinacota (6332 m) are captured under the Milky Way in April 2010 by TWAN photographer Stephane Guisard from 5000m high in Chilean Andes. The photo is made with a single 20-second exposure using a DSLR camera (at high ISO) and 35mm lens. See more TWAN photos of Lauca National Park.
What is this fan shaped bright cloud among stars? Did TWAN photographer capture a UFO?
In a clear evening of June 2007, Babak Tafreshi (along with another TWAN photographer Oshin Zakarian) witnessed a strange and luminous cloud in the night sky above Alborz Mountains of Iran. Although he has been under starry skies around the planet for hundreds of times, he had never experienced a similar phenomena. The object started out patchy, shapeless and dim; it quickly brightened and formed a blue-tinted cone with a nose of magnitude -2 to -3. The cloud raced across the sky moving about 20 degrees per minute. In this image which shows the first moments of the cloud appearance from the top of Dizin peak (3400 m), the two bright stars in the middle are Castor and Pollux in Gemini, while dazzling planet Venus is on the upper left in conjunction with the Beehive or M44 star cluster in Cancer.
APOD: Mysterious Streaks Over Turkey (2007 Aug 15)What are the streak at the right edge of this image near the belt of Orion?
The streaks in the above image taken near Ankara, Turkey on 12 August 2007 would be identified at first glance as meteors from the Perseids meteor shower peaking just that night. Unexpectedly, however, these streaks do not point back to the Perseids radiant in Perseus (top center). Then what is their origin?
The image is a composite of several shots captured over the time span of 40 minutes. Other visible celestial icons include the V-figure of Taurus and the Pleiades star cluster, planet between them, bright star Capella near the center, and the rising stars of Gemini in the bottom center. Note the elongated light rising from the horizon toward the Taurus and passing through the winter Milky Way. This is the zodiacal light (sunlight reflection from dust in the solar system plane).
Photo by Tunc Tezel
What are the dark vertical bands on the right side of this image above prominent stars of Taurus (including Pleiades) and through the constellation Perseus?
On a September night of 2010 TWAN photographer Yuichi Takasaka was near the town of Yellowknife in the Northwest Territories of Canada. The town is known as one of the world's best urban locations to see aurora or northern lights. An active aurora display is captured on the left (north east) while there are parallel and strangely aligned vertical dark bands on the right (east) between weaker aurora rays. In a panoramic image of the view the photographer has noticed the faint lines also 180 degrees away, at the opposite direction above the western horizon. The images were taken at about 2:30 am local time on September 19. The moon was about to set (at 2:40) and sunrise was about 5 hours later.
Do these lines represent a rare kind of black aurora (also known as anti aurora); a phenomena which is well recorded in many aurora images? Are they digital noise by the camera? Or do they display an atmospheric phenomenon related to the setting moon or shadows in the aurora lights made in the lower atmosphere?
Yuichi Takasaka has been photographing aurora for 20 years and this is the first time he has seen these vertical lines in his images. See TWAN special Aurora Gallery. More about dark aurora on NASA's APOD and here. More about various atmospheric phenomena on the Atmospheric Optics.
Happy New Year 2011!
Test your knowledge of the night sky with this edition of TWAN Mystery.
In a clear night of late November 2009 TWAN photographer Babak Tafreshi made this single exposure image with a 50-mm lens from high altitude slopes of Himalayas in the Sagarmatha National Park of Nepal, on the trek to Mount Everest base camp. The location was at latitude 28 degrees north and the image looks to the southern horizon in the early morning sky. Try to find out:
See more TWAN images of Nepal Himalayas on this gallery.
- What is the bright star at the right side?
- What is the notable deep sky object right at the horizon?
- What has caused the large patchy red glow in the upper part of the image?
What could be the identity of this trailing light in the sky above Yellowknife, northern Canada? In the sequence of photos a passing airplane, clouds, and rays of aurora are also captured in the sky. The mystery light appeared in the sky between 01:31 and 1:45 local summer time (GMT -6 hours) of Sep. 23, 2011. Provided by TWAN photographer Kwon O Chul see this sequence in a timelapse video that further shows what appeared in the sky.
