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Nova Sagittarii observation, March 29

View larger. | Finder chart for Nova Sagittarii via Tom Wildoner.

Finder chart for Nova Sagittarii 2015 No. 2. This chart is for Tom Wildoner’s observing location in Pennsylvania, but the nova’s location with respect to these background stars will be the same from across the globe. Chart credit to Stellarium, via Tom Wildoner. Used with permission.

The brightness of this unusual nova has gone up and down and now back up again. EarthSky friend Tom Wildoner tells you how to see the nova before it’s gone!

This date in science: Biggest earthquake in North America

After the 1964 Good Friday Earthquake in Alaska, both human and natural areas sustained damage.

During the 1964 Good Friday Earthquake in Alaska, both human and natural areas sustained damage. A large landslide caused the damage shown here to many homes in Anchorage’s Turnagain-By-The-Sea subdivision. Image via U.S. National Oceanic and Atmospheric Administration/Wikimedia Commons.

March 27, 1964. On this date, at 5:36 p.m. local time, a 9.2 magnitude earthquake struck in the Prince William Sound region of Alaska, causing extensive initial damage and a subsequent tsunami. In Anchorage, dozens of blocks of buildings were leveled or damaged. Valdez, closest to the epicenter, was destroyed. The quake is now known as the Good Friday Earthquake.

Dwarf planet Ceres gets place names

View larger. | Topographic map of Ceres, with quad names.  Emily Lakdawalla of the Planetary Society created this image.  She applied quad names - announced last week at the Lunar and Planetary Science Conference in Houston - to a digital elevation model of Ceres.  The crater with the bright feature is right on the boundary between the Palo and Ebisu quads.  NASA / JPL / UCLA / MPS / DLR / IDA / JohnVV / Emily Lakdawalla

View larger. | Topographic map of Ceres, with quad names. NASA / JPL / UCLA / MPS / DLR / IDA / JohnVV / Emily Lakdawalla

Emily Lakdawalla of the Planetary Society created this image after last week’s Lunar and Planetary Science Conference in Houston. At the conference, scientists announced names for various regions (quads) on Ceres, and Lakdawalla applied those names to a digital elevation model of the little world, resulting in the image above.

Do stars make sounds?

Photo by Jason Brownlee.  Visit Jason Brownlee Design on Facebook

If only we could hear them, would the stars make a sound? Photo posted to EarthSky Facebook by Jason Brownlee.

Is there an actual harmony of the spheres? A chance discovery by a team of researchers has provided experimental evidence that stars might generate sound. They announced their discovery March 23, 2015.

When is our next Great Comet?

A night under the stars and a comet, C/1996 O1 Hale-Bopp. Owing to its orbital inclination and modest perihelion, 0.95 AU, it remained visible to the unaided eye for 18 months. (Credit: ©1997 Jerry Lodriguss / www.astropix.com)

Comet Hale-Bopp remained visible to the unaided eye for 18 months in 1996-97. Photo ©1997 Jerry Lodriguss / www.astropix.com. Used with permission.

The Southern Hemisphere has had two Great Comets recently – McNaught in 2007 and Lovejoy in 2011. But what about the Northern Hemisphere? Our last widely seen Comet was Hale-Bopp in 1996-97. Comet West in 1976 was probably our last Great Comet. When will we see our next Great Comet?

Surprise! Arctic sea ice record winter low

Here the 2015 maximum is compared to the 1979-2014 average maximum shown in yellow. A distance indicator shows the difference between the two in the Sea of Okhotsk north of Japan. Image via NASA's Goddard Space Flight Center

Here the 2015 maximum is compared to the 1979-2014 average maximum shown in yellow. A distance indicator shows the difference between the two in the Sea of Okhotsk north of Japan. Image via NASA’s Goddard Space Flight Center

The National Snow & Ice Data Center announced last week that 2014-2015’s Arctic sea ice maximum extent was the lowest yet recorded. In addition, sea ice likely hit its maximum nearly two weeks earlier than in recent decades, on February 25, 2015. It happened even as unusually cold air and stormy weather occurred across the eastern half of the United States and Canada this year.

Dates of lunar and solar eclipses in 2015 and 2016

Solar eclipse November 3, 2013 by Ken Christison

Solar eclipse November 3, 2013 by Ken Christison

The solar eclipse of March 20, 2015 is over. The next eclipse is a total eclipse of the full moon on April 4, 2015. It’ll last less than five minutes, making it the shortest total lunar eclipse of the 21st century. Follow the links inside to learn the dates for upcoming solar and lunar eclipses in 2015 and 2016.

Is it possible to have three eclipses in one month?

solar-eclipse-annular

Is it possible to have three eclipses in one month? Yes, it’s possible. You can have two solar eclipses and one lunar eclipse in one month. Or you can have two lunar eclipses and one solar eclipse in one month. However, it’s quite rare to have three eclipses in one calendar month. Follow the links inside to learn more about past and future months in which there are three eclipses.

A Chinese perspective on the spring equinox

Image via The Dragon

Image via The Dragon

In Chinese thought, spring is associated with the color green, the sound of shouting, the liver organ, the wood element, the climate of wind, things sprouting, your eyes, your anger, patience and altruism – and a green dragon. Not surprisingly, spring is also associated with the direction east, the sunrise direction as Earth spins us toward the beginning of each new day.

Angara rocket key to Russia’s launch future

View larger. | Angara would be capable of launching cosmonauts to the moon.  Illustration by Adrian Mann.  Used with permission.

Artist’s concept of a planned future version of the Angara rocket. It’ll be capable of sending cosmonauts to the moon, lifting modules to construct a future Russian space station and launching interplanetary probes. Illustration by Adrian Mann. Used with permission.

Just a week after announcing intentions to build their own space station and leave the International Space Station in 2024 – with plans to try Mars again and send cosmonauts to the moon – Russian Space Agency officials are calling for the postponement of a heavy lift launch vehicle. In a recent announcement, they say they will reply on the Angara family of launch vehicles, over 20 years in the making, with recently accomplished successful test flights. Russia’s new plans are yet another change among launch providers in the space industry, an industry with numerous aged launched vehicles facing increasing competition.