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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.

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.

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.

New report detects substantial rise in greenhouse gases

Emissions from a coal fired power plant. Image Credit: Robert S. Donovan.

Emissions from a coal fired power plant. Image Credit: Robert S. Donovan.

A new report from the World Meteorological Organization (WMO) released on September 9, 2014 has detected a substantial rise in the levels of greenhouse gases in the atmosphere. From 2012 to 2013, carbon dioxide concentrations increased by 2.9 parts per million and now total 396 parts per million, according to the report. The most recent rise in carbon dioxide is the largest annual change seen for this gas since 1984.

ESA announces landing site on Rosetta’s comet

ESA has announced the Philae lander's touch down point.  It's Site J!

ESA has announced the Philae lander’s touch down point. It’s Site J!

Just announced.

Landing Site for Rosetta’s Philae Lander has been decided. It is Site J the one next to the crater on the top of the head of the comet 67P/Churyumov–Gerasimenko.

Mars moon Phobos in front of sun on August 8

Photo of Mars moon Phobos in front of the sun.  Image Credt: NASA / JPL / Malin Space Science Systems. Mars Science Laboratory Curiosity.

Image Credit: NASA / JPL / Malin Space Science Systems. Mars Science Laboratory Curiosity.

It was Sol 713, or the 713th day since the touchdown of NASA’s Mars Curiosity rover on Mars. The martian early morning sun was only 17.75 degrees above the eastern horizon, when, from the floor of the Gale Crater, the rover’s camera caught Mars’ larger moon Phobos passing in front of the sun.

Significant auroras predicted for tonight

View larger. | Colin Chatfield near Saskatoon, SK, Canada captured this aurora Friday morning.  Taken with a Canon 7D and Tokina 10-17mm fisheye lens at 10mm, f/3.5, 20 sec exp, ISO 800.  Visit Colin Chatfield on Facebook.

View larger. | Colin Chatfield near Saskatoon, SK, Canada captured this aurora Friday morning.

Due to two recent events on the sun – including an X-flare from Active Region 2158 on the sun on Wednesday – reports from NOAA and elsewhere predict good chances for significant auroral displays. Auroras will be possibly observable at latitudes as far south as the northern U.S. states including, for example, Wisconsin, Michigan, and New York, and maybe even farther south. Spaceweather.com reports:

The first of two CMEs expected to hit Earth’s magnetic field on Sept. 12 has arrived, and a minor (G1-class) geomagnetic storm is underway as a result of the impact. The second and potentially more powerful CME is still en route. NOAA forecasters say geomagnetic storming could become strong (G3-class) during the late hours of Sept. 12 and Sept 13 after the second CME arrives.

Rosetta spacecraft selfie with comet

Via ESA/Rosetta/Philae/CIVA.

Rosetta spacecraft ‘selfie’ with comet 67P/Churyumov–Gerasimenko, imaged Sunday, September 7, 2014. Image via ESA/Rosetta/Philae/CIVA.

Here is a Rosetta ‘selfie’ with comet 67P/Churyumov–Gerasimenko in background. It was taken by the CIVA camera onboard the Philae Lander. This is the same camera that will be acquiring images from the surface of the comet itself, when the Philae lander sets down on the comet in November.

What are cloud streets?

cloud-streets-bering-sea-20jan2006-540

Cloud streets over the Bering Sea on January 20, 2006. Image Credit: Jesse Allen, NASA.

Your Friday FAQ. Find out what they are and how they form. And check out these cool images!