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Tornado Alley storm season starting and ending earlier

A supercell storm, known to produce violent tornadoes, forms in Courtney, Oklahoma in April 2014. A new study shows that peak tornado activity is occurring nearly two weeks earlier in Oklahoma, Kansas, and northern Texas, according to a new study published in Geophysical Research Letters.  Image via Flickr user Kelly DeLay

A supercell storm, known to produce violent tornadoes, over Courtney, Oklahoma in April 2014. Image via Flickr user Kelly DeLay

Tornado records from Nebraska, Kansas, Oklahoma, and northern Texas – an area of high tornado activity dubbed Tornado Alley — show that peak tornado activity is starting and ending earlier than it did 60 years ago. That’s according to a new study published in Geophysical Research Letters on September 10, 2014.

Racing toward Pluto, spacecraft spies tiny moon Hydra

Detection of tiny Pluto moon Hydra in July 2014 by New Horizons spacecraft.  Image via NASA / JHU / APL / SRI. New Horizons spacecraft.

Detection of tiny Pluto moon Hydra in July 2014 by New Horizons spacecraft. Image via NASA / JHU / APL / SRI. New Horizons spacecraft.

Pluto’s moon Hydra was detected twice by the New Horizons spacecraft LORRI (LOng Range Reconnaisance Imager) camera. The detections were made on July 18, 2014 and a few days later on July 20, from a distance of 430 million kilometers / 267 million miles.

Merging galaxies can produce disk galaxies

View larger. | Distributions of gas in merging galaxies observed by radio telescopes. Contours indicate the radio intensity emitted from CO gas. The color shows the motion of gas. The red color indicates gas is moving away from us while the blue color is coming closer to us. The gradation from red to blue means that gas is rotating in a disk-like manner around the center of the galaxy.      Credit: ALMA (ESO/NAOJ/NRAO)/SMA/CARMA/IRAM/J. Ueda et al.

Distributions of gas in merging galaxies observed by radio telescopes. The gradation from red to blue means that gas is rotating in a disk-like manner around the center of the galaxy. Image via ALMA (ESO/NAOJ/NRAO)/SMA/CARMA/IRAM/J. Ueda et al.

It’s been part of the conventional wisdom of modern astronomy that mergers between galaxies – which are common throughout the history of the universe – lead to the formation of massive elliptical galaxies. That idea is based on computer simulations performed in the 1970s, which have held sway ever since. Now, however, astronomers have the first evidence that merging galaxies can create disk galaxies.

New map of 15 years of CO2 emissions

 View larger |  Image credit: Gurney lab

View larger | Image credit: Gurney lab

An international research team has developed a new system to quantify 15 years of CO2 emissions, every hour, for the entire planet, down to the city scale.

Polar mesospheric clouds over the Ukraine

Image credit: NASA

This sunset shot shows PMCs as a thin bright line, far above the lowest weather layer of the atmosphere (the troposphere). Image credit: NASA

Polar mesospheric clouds are wispy and elusive. They form 80 to 100 kilometers (50 to 60 miles) above the ground – far higher in the atmosphere than most ordinary clouds. Astronauts aboard the International Space Station (ISS), flying at 350 kilometers (220 miles) up, are ideally placed to observe them.

Sun passes out of Leo and into Virgo on September 17

2013-sept-16-virgo-leo-sun-night-sky-chart

Today – September 17, 2014 – the sun exits the constellation Leo and enters the constellation Virgo. The sun will remain in front of the constellation Virgo the Maiden until it enters the constellation Libra the Scales on October 31. So, when the equinox arrives on September 23, the sun will be in front of the constellation Virgo. And so it has been for thousands of years. But it won’t always be that way.

A push for climbing reform after Sherpa deaths on Everest

The Khumbu Icefall is a notoriously dangerous part of Mount Everest. Sixteen Nepalese guides died here on April 18 in one of the worst accidents in the mountain’s history. Photo credit: Mahatma4711

The Khumbu Icefall is a notoriously dangerous part of Mount Everest. Sixteen Nepalese guides died here on April 18, 2014 in one of the worst accidents in the mountain’s history. Photo credit: Mahatma4711

A major workshop in late August 2014 represents a significant change in the debates about climbing expeditions on Mount Everest, with significance across the Himalayas and beyond. The Participatory Workshop on Roles, Responsibilities & Rights of Mountaineering Workers, held on August 29 and 30 in Kathmandu, emerged from the unsettled outcome of the tragic accident of April 18, when 16 Nepalese guides were killed at the Khumbu Icefall on Mount Everest.

Earthquake-induced landslide at Seward Glacier

NASA Earth Observatory images created by Jesse Allen, using digital photographs provided by Kelly Brunt, MABEL campaign.

Snow from a large avalanche cascaded down the mountainside and covered an older slide. NASA Earth Observatory images via Jesse Allen and Kelly Brunt, MABEL campaign.

A magnitude-6.0 earthquake struck beneath Seward Glacier in northwestern Canada on July 17, 2014, and, by a lucky coincidence, NASA scientists, engineers, and pilots were gearing up for near-daily flights over the area while developing processes for interpreting data from ICESat-2, a satellite scheduled for launch in 2017. They were able to capture the image above of a landslide, apparently caused by the earthquake, which had obscured remnants of an older slide.

New catalog of visible Milky Way charts 219 million stars

View larger. | This new map shows the density of objects within our Milky Way galaxy. It's a small section of a larger map, but it shows in exquisite detail the complex patterns of obscuration in the galaxy, due to interstellar dust.  Image via Hywel Farnhill, University of Hertfordshire.

View larger. | This new map shows the density of objects within our Milky Way galaxy. It’s a small section of a larger map, but it shows in exquisite detail the complex patterns of obscuration in the galaxy, due to interstellar dust. Image via Hywel Farnhill, University of Hertfordshire.

Astronomers at the University of Hertfordshire spent 10 years using a telescope in the Canary Islands to chart no fewer than 219 million stars in our galaxy. Their new catalog is the largest of its kind ever produced. It shows the visible part of the northern part of our home galaxy, the Milky Way.

Major Hurricane Odile slams Baja Peninsula in Mexico

Extensive damage in the Cabo San Lucas Airport. Image via Twitter via @MexicanadeModa

Extensive damage in the Cabo San Lucas Airport. Image via Twitter via @MexicanadeModa

The active Eastern Pacific hurricane season continues to churn up powerful storms. On September 15, 2014 at 12:45 a.m. EDT (445 UTC), major Hurricane Odile slammed into Mexico’s Baja Peninsula. It made landfall in Cabo San Lucas, a popular tourist destination, with a population of roughly 70,000 people. The storm made landfall as a Category 3 storm with sustained winds of 125 miles per hour (mph) or 110 knots. Odile was the first known storm to hit Cabo San Lucas as such a strong intensity. Photos of the damage and firsthand reports, here.