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How to See a Once-in-a-Generation Supermoon Eclipse This Weekend

2 minute read
By Daniel White

Three decades have passed since the last time Earth was witness to the triple crown of lunar events — a full moon, a lunar eclipse, and a lunar perigee all at the same time — and now people in north America will be able to see a “supermoon eclipse” this weekend.

A lunar eclipse is when the Earth comes between the full moon and the sun. Although completely in the Earth’s shadow, the moon still receives a bit of reddish sunlight. Unlike a solar eclipse, there’s no special equipment needed to view it. A supermoon is when the moon is in perigee, or the closest point to the Earth it will reach. Sunday’s moon will be about 14% larger than normal, according to NASA.

There have only been five times since 1900 where the supermoon has coincided with a total lunar eclipse— and the next won’t happen for another 18 years.

Begin looking to the moon around 8 p.m. EDT on Sunday Sept 27, with the total eclipse setting in around 10 p.m. But if there’s cloud cover or you’re unable to get to a clear patch of sky then a livestream will be on TIME.com, hosted by Slooh. The stream will be hosted by Paul Cox and Bob Berman.

Here are the Best Photos from Cassini's Mission to Saturn

The spinning vortex of Saturn's north polar storm resembles a deep red rose of giant proportions surrounded by green foliage in this false-color image from NASA's Cassini spacecraft. Measurements have sized the eye at a staggering 1,250 miles (2,000 kilometers) across with cloud speeds as fast as 330 miles per hour (150 meters per second).This image is among the first sunlit views of Saturn's north pole captured by Cassini's imaging cameras. When the spacecraft arrived in the Saturnian system in 2004, it was northern winter and the north pole was in darkness. Saturn's north pole was last imaged under sunlight by NASA's Voyager 2 in 1981; however, the observation geometry did not allow for detailed views of the poles. Consequently, it is not known how long this newly discovered north-polar hurricane has been active.The images were taken with the Cassini spacecraft narrow-angle camera on Nov. 27, 2012, using a combination of spectral filters sensitive to wavelengths of near-infrared light. The images filtered at 890 nanometers are projected as blue. The images filtered at 728 nanometers are projected as green, and images filtered at 752 nanometers are projected as red. In this scheme, red indicates low clouds and green indicates high ones.The view was acquired at a distance of approximately 261,000 miles (419,000 kilometers) from Saturn and at a sun-Saturn-spacecraft, or phase, angle of 94 degrees. Image scale is 1 mile (2 kilometers) per pixel. The Cassini-Huygens mission is a cooperative project of NASA, the European Space Agency and the Italian Space Agency. NASA's Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, manages the mission for NASA's Science Mission Directorate, Washington, D.C. The Cassini orbiter and its two onboard cameras were designed, developed and assembled at JPL. The imaging operations center is based at the Space Science Institute in Boulder, Colo.For more information about the Cassini-Huygens
The spinning vortex of Saturn's north polar storm on Nov. 27, 2012. Taken using a combination of spectral filters sensitive to wavelengths of near-infrared light. NASA/JPL/Space Science Institute
Cassini - Mimas
Saturn's lonely moon, Mimas on Nov. 30, 2004.AFP/Getty Images
Cassini Saturn Rings
The rings of Saturn captured by Cassini before it entered the orbit on 21 Jun. 2004. SSPL/Getty Images
Cassini - Dione
A view of Saturn's moon Dione, taken during a close flyby on Jun. 16, 2015. NASA/JPL-Caltech/Space Science Institute
Cassini Crescent Moon
The moons Titan, Mimas, and Rhea, captured by Cassini in this image released on Jun. 22, 2015.NASA/JPL-Caltech/Space Science Institute
This Cassini narrow-angle camera image -- one of those acquired in the survey conducted by the Cassini imaging science team of the geyser basin at the south pole of Enceladus -- was taken as Cassini was looking across the moon's south pole. At the time, the spacecraft was essentially in the moon's equatorial plane. The image scale is 1280 feet (390 meters) per pixel and the sun-Enceladus-spacecraft, or phase, angle is 162.5 degrees.The image was taken through the clear filter of the narrow angle camera on Nov. 30, 2010, 1.4 years after southern autumnal equinox. The shadow of the body of Enceladus on the lower portions of the jets is clearly seen.In an annotated version of the image, the colored lines represent the projection of Enceladus' shadow on a plane normal to the branch of the Cairo fracture (yellow line), normal to the Baghdad fracture (blue line) and normal to the Damascus fracture (pink line).Post-equinox images like this, clearly showing the different projected locations of the intersection between the shadow and the curtain of jets from each fracture, were useful for scientists in checking the triangulated positions of the geysers, as described in a paper by Porco, DiNino, and Nimmo, and published in the online version of the Astronomical Journal in July 2014: http://dx.doi.org/10.1088/0004-6256/148/3/45.A companion paper, by Nimmo et al. is available at: http://dx.doi.org/10.1088/0004-6256/148/3/46.The Cassini-Huygens mission is a cooperative project of NASA, the European Space Agency and the Italian Space Agency. NASA's Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, manages the mission for NASA's Science Mission Directorate, Washington. The Cassini orbiter and its two onboard cameras were designed, developed and assembled at JPL. The imaging operations center is based at the Space Science Institute in Boulder, Colorado.For more information about the Cassini-Huygens mission visit http://saturn.j
A geyser basin at the south pole of Enceladus on Nov. 30, 2010. NASA/JPL-Caltech/Space Science Institute
Cassini - Saturn - Storm
A huge northern storm on Saturn In mid-Sept. 2004.Barcroft Media/Getty Images
Dione Chasm Cassini
Chasms on Dione. The image was taken in visible light with the Cassini spacecraft narrow-angle camera on April 11, 2015. NASA/JPL-Caltech/Space Science Institute
Cassini - Pandora - NASA
Pandora on the edge of Saturn's ring on Nov. 8, 2009.NASA/JPL/Space Science Institute
Cassini - Saturn
View of Saturn's rings as they surround the planet. Universal History Archive—UIG/Getty Images
Cassini - Earth - Moon
The Earth and the moon photographed by NASA's Cassini spacecraft on Jul. 19, 2013.NASA/JPL-Caltech/Space Science Institute
Speeding toward pale, icy Dione, Cassini's view is enriched by the tranquil gold and blue hues of Saturn in the distance. The horizontal stripes near the bottom of the image are Saturn's rings. The spacecraft was nearly in the plane of the rings when the images were taken, thinning them by perspective and masking their awesome scale. The thin, curving shadows of the C ring and part of the B ring adorn the northern latitudes visible here, a reminder of the rings' grandeur.It is notable that Dione, like most of the other icy Saturnian satellites, looks no different in natural color than in monochrome images.Images taken on Oct. 11, 2005, with blue, green and infrared (centered at 752 nanometers) spectral filters were used to create this color view, which approximates the scene as it would appear to the human eye. The images were obtained with the Cassini spacecraft wide-angle camera at a distance of approximately 39,000 kilometers (24,200 miles) from Dione and at a Sun-Dione-spacecraft, or phase, angle of 22 degrees. The image scale is about 2 kilometers (1 mile) per pixel.
Pale, icy Dione, taken on Oct. 11, 2005.NASA/JPL/Space Science Institute—NASA/JPL/Space Science Institute
Cassini Tethys
Red arcs in the northern area of Tethys on April 2015.NASA/JPL/Space Science Institute
Saturn Aurora Cassini
An aurora on Saturn. The composite image was made from 65 individual observations by Cassini's visual and infrared mapping spectrometer on Nov. 1, 2008. The observations were each six minutes long. NASA/SSPL/Getty Images
Saturn cassini polar vortex storm 2013
The Cassini spacecraft captured the storms at Saturn's north pole in this false color image released in April 2013. The storm appears dark red while the fast-moving hexagonal jet stream framing it is a yellowish green. Low-lying clouds circling inside the hexagonal feature appear in orange. A second, smaller vortex pops out in teal at the lower right of the image. The rings of Saturn appear in vivid blue at the top right. NASA/JPL-Caltech/SSI
Saturn's Enceladus - Cassini
Saturn's moon Enceladus brightly reflects sunlight before a backdrop of the planet's rings.Universal History Archive/UIG/Getty Images
Cassini - Rhea
The Cassini spacecraft observed three of Saturn's moons set against the night side of the planet in this image from April 2011. NASA/JPL-Caltech/Space Science Institute
Cassini - Phoebe
Phoebe, captured during Cassini's flyby on Jun. 11, 2004. NASA/JPL-Caltech/Space Science Institute
Five moons -- dominated by Rhea in the foreground -- share this Cassini spacecraft view with Saturn's rings seen nearly edge-on. Rhea (1,528 kilometers, or 949 miles across) is largest here and is closest to Cassini. Dione (1,123 kilometers, or 698 miles across) can be seen just above the rings near the center of the image. Tiny Prometheus (86 kilometers, or 53 miles across) is just barely visible in the rings to the right of Dione. Epimetheus (113 kilometers, or 70 miles across) is to the right of the rings, and Tethys (1,062 kilometers, or 660 miles across) is on the extreme right of the image. This view looks toward the anti-Saturn side of Rhea and toward the northern, sunlit side of the rings from just above the ringplane. The image was taken in visible light with the Cassini spacecraft wide-angle camera on Jan. 11, 2011. The view was obtained at a distance of approximately 61,000 kilometers (38,000 miles) from Rhea and at a Sun-Rhea-spacecraft, or phase, angle of 15 degrees. Scale on Rhea is 4 kilometers (2 miles) per pixel. The Cassini-Huygens mission is a cooperative project of NASA, the European Space Agency and the Italian Space Agency. The Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, manages the mission for NASA's Science Mission Directorate, Washington, D.C. The Cassini orbiter and its two onboard cameras were designed, developed and assembled at JPL. The imaging operations center is based at the Space Science Institute in Boulder, Colo. For more information about the Cassini-Huygens mission visit http://saturn.jpl.nasa.gov/. The Cassini imaging team homepage is at http://ciclops.org.
Five moons of Saturn dominated by Rhea in the foreground on Jan. 11, 2011.NASA/JPL/Space Science Institute—NASA/JPL/Space Science Institute
Cassini - Iapetus
The Cassini spacecraft takes one of its last good looks at Iapetus, a Saturnian moon.UIG/Getty Images
NASA's Cassini imaging scientists processed this view of Saturn's moon Hyperion, taken during a close flyby on May 31, 2015. This flyby marks the mission's final close approach to Saturn's largest irregularly shaped moon.
Saturn's moon Hyperion, taken during a close flyby on May 31, 2015. This flyby marks the mission's final close approach to Saturn's largest irregularly shaped moon. NASA/JPL-Caltech/Space Science Institute
Cassini - Atlas
The Cassini spacecraft captures a glimpse of the moon Atlas shortly after emerging from Saturn's shadow on Jan. 23, 2014.NASA/JPL-Caltech/Space Science Institute
Cassini - Mimas
Mimas, Dione and Titan on May 27, 2015. The image is taken using a spectral filter which preferentially admits wavelengths of near-infrared light centered at 728 nanometersNASA/JPL/Space Science Institute
A swing high above Saturn by NASA's Cassini spacecraft revealed this stately view of the golden-hued planet and its main rings on Oct. 10, 2013
A swing high above Saturn by NASA's Cassini spacecraft revealed this stately view of the golden-hued planet and its main rings on Oct. 10, 2013.NASA/JPL

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