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First images from Sunday’s last close sweep of Hyperion

Image via Cassini

A crescent view of Saturn’s moon Hyperion, captured on Cassini’s final close sweep past this moon on Sunday, May 31. Cassini’s closest distance on Sunday was 21,000 miles (34,000 kilometers) from Hyperion. In this image, you’re seeing primarily the night side of the moon. Image via ASA / JPL / ESA Cassini.

NASA’s Cassini spacecraft made its final close approach to Saturn’s large, odd, tumbling, irregularly shaped moon Hyperion on Sunday. Click inside for more first images from Sunday’s close pass.

Crashing comets may explain lunar swirls

Source of mysterious lunar swirls New research suggests that comet collisions could explain the formation of lunar swirls like these at Mare Marginis on the Moon’s far side. Image: NASA/Lunar Reconnaissance Orbiter

New research suggests that comet collisions could explain the formation of lunar swirls like these at Mare Marginis on the moon’s far side. Image via NASA/Lunar Reconnaissance Orbiter

Brown University researchers said on June 2 that they have new evidence that several comet collisions over the last 100 million years created the wispy bright regions scattered across the moon’s surface. These enigmatic features are known to scientists as lunar swirls. The researchers used state-of-the-art computer models to simulate the dynamics of comet impacts on lunar soil and say this new work suggests comets can explain features of the mysterious swirls.

Shock collision inside black hole jet

Scientists assembled this time-lapse movie of a plasma jet blasting from a black hole in a distant galaxy from 20 years of Hubble Space Telescope observations. The video shows the core of the elliptical galaxy NGC 3862, located some 260 million light-years from Earth. It shows a rear-end collision between two high-speed knots of matter in the jet.

The secrets of night-shining clouds

Noctilucent clouds captured from Soomaa National Park, Estonia, in 2009. Image via Martin Koitmäe via Wikimedia Commons.

What are noctiilucent clouds? Glowing silver-blue clouds that sometimes light up summer night skies in polar regions, after sunset and before sunrise, are called noctilucent or “night-shining” clouds. Scientists studying these clouds have found that year-to-year changes in them are closely linked to weather and climate across the globe.

NOAA forecasts slow 2015 Atlantic hurricane season

NOAA 2015 Hurricane Forecast. Image Credit: NOAA/NHC

NOAA 2015 Hurricane Forecast. Image via NOAA/NHC

With the developing El Niño in the Pacific Ocean, NOAA announced on May 27, 2015 that it is forecasting a below-average 2015 Atlantic hurricane season. That season runs each year from June 1 to November 30. While NOAA scientists are forecasting fewer named storms this year than in some previous years, it is important to note that it only takes one storm to make it a bad season for any given location.

Now is the time to prepare for hurricanes

In conjunction with the start of the hurricane season in the Eastern Pacific (May 15) and Atlantic Oceans (June 1), officials with the U.S. National Oceanic and Atmospheric Administration (NOAA) are urging residents in coastal areas to develop preparedness plans.

New human ancestor found in Ethiopia

Lead author Yohannes Haile-Selassie of The Cleveland Museum of Natural History holds casts of the jaws of Australopithecus deyiremeda, a new human ancestor from Ethiopia.  Photo: Laura Dempsey

Lead author Yohannes Haile-Selassie of The Cleveland Museum of Natural History holds casts of the jaws of Australopithecus deyiremeda, a new human ancestor from Ethiopia. Photo: Laura Dempsey

Humans, meet your new ancestor. This new hominin species likely lived at the same time – and is believed by scientists to be a close relative to – the famous “Lucy” species first discovered in Ethiopia in 1974. That is, this species lived 3.3 to 3.5 million years ago and is thought to be a human ancestor (although it is not an identical species to Lucy, according to these scientists).

What is a coronal mass ejection or CME?

Aug 2012 CME

Aug 2012 CME

Every so often, the sun burps with the power of 20 million nuclear bombs.  These hiccups are known as coronal mass ejections (CMEs)—powerful eruptions near the surface of the sun driven by kinks in the solar magnetic field.  The resulting shocks ripple through the solar system and can interrupt satellites and power grids on Earth. During a CME, enormous bubbles of superheated gas—called plasma—are ejected from the sun.  Over the course of several hours, one billion tons of material are lifted off the sun’s surface and accelerated to speeds of one million miles per hour.  This can happen several times a day when the sun is most active.

Video: Translating climate change to music

University of Minnesota undergraduate student Daniel Crawford has composed a piece of music based on temperature data – at different zones of latitude on Earth – since 1880. He calls his composition “Planetary Bands, Warming World.” Each performer in the video above represents one of four zones in the Northern Hemisphere: near the equator (cello), the midlatitudes (viola), the upper latitudes (violin), and the Arctic (violin). Higher notes correspond to high temperatures. Listen, and see if the piece evokes for you what Daniel hopes will be “a more visceral response” to climate data than what we sometimes get reading or seeing charts and graphs.

Hawaii governor says Thirty Meter Telescope has right to continue

Artist's concept of the Thirty Meter Telescope.

Artist’s concept of the Thirty Meter Telescope.

Hawaii Gov. David Ige this week announced his support for continuing construction of the controversial Thirty Meter Telescope (TMT) at Mauna Kea, considered a sacred mountain by many native Hawaiians. Protests over Mauna Kea’s use by astronomers halted construction on the $1.5-billion TMT project last month. At a press conference on Tuesday, Ige said the project has the right to proceed, and he laid out some new rules, which include removing one-quarter of the existing 13 telescopes on Mauna before TMT starts operating in the mid-2020s.