Aurora over Icelandic Fault Aurora over Icelandic Fault

Admire the beauty but fear the beast. The beauty is the aurora overhead, here taking the form of great green spiral, seen between picturesque clouds with the bright Moon to the side and stars in the background. The beast is the wave of charged particles that creates the aurora but might, one day, impair civilization. Exactly this week in 1859, following notable auroras seen all across the globe, a pulse of charged particles from a coronal mass ejection (CME) associated with a solar flare impacted Earth's magnetosphere so forcefully that they created the Carrington Event. A relatively direct path between the Sun and the Earth might have been cleared by a preceding CME. What is sure is that the Carrington Event compressed the Earth's magnetic field so violently that currents were created in telegraph wires so great that many wires sparked and gave telegraph operators shocks. Were a Carrington-class event to impact the Earth today, speculation holds that damage might occur to global power grids and electronics on a scale never yet experienced. The featured aurora was imaged last week over Thingvallavatn Lake in Iceland, a lake that partly fills a fault that divides Earth's large Eurasian and North American tectonic plates. via NASA http://ift.tt/2byz7QQ

Abell 370: Galaxy Cluster Gravitational Lens Abell 370: Galaxy Cluster Gravitational Lens

What is that strange arc? While imaging the cluster of galaxies Abell 370, astronomers had noted an unusual arc to the right of many cluster galaxies. Although curious, one initial response was to avoid commenting on the arc because nothing like it had ever been noted before. In the mid-1980s, however, better images allowed astronomers to identify the arc as a prototype of a new kind of astrophysical phenomenon -- the gravitational lens effect of entire cluster of galaxies on background galaxies. Today, we know that this arc actually consists of two distorted images of a fairly normal galaxy that happened to lie far behind the huge cluster. Abell 370's gravity caused the background galaxies' light -- and others -- to spread out and come to the observer along multiple paths, not unlike a distant light appears through the stem of a wine glass. In mid-July of 2009, astronomers used the then just-upgraded Hubble Space Telescope to image Abell 370 and its gravitational lens images in unprecedented detail. Almost all of the yellow images featured here are galaxies in the Abell 370 cluster. An astute eye can pick up many strange arcs and distorted arclets, however, that are actually images of more distant galaxies. Studying Abell 370 and its images gives astronomers a unique window into the distribution of normal and dark matter in galaxy clusters and the universe. via NASA http://ift.tt/2bXXoiK

Lunar Orbiter Earthset Lunar Orbiter Earthset

August 10th was the 50th anniversary of the launch of Lunar Orbiter 1. It was the first of five Lunar Orbiters intended to photograph the Moon's surface to aid in the selection of future landing sites. That spacecraft's camera captured the data used in this restored, high-resolution version of its historic first image of Earth from the Moon on August 23, 1966 while on its 16th lunar orbit. Hanging almost stationary in the sky when viewed from the lunar surface, Earth appears to be setting beyond the rugged lunar horizon from the perspective of the orbiting spacecraft. Two years later, the Apollo 8 crew would record a more famous scene in color: Earthrise from lunar orbit. via NASA http://ift.tt/2chQLuW

Closest Star has Potentially Habitable Planet Closest Star has Potentially Habitable Planet

The star closest to the Sun has a planet similar to the Earth. As announced yesterday, recent observations confirmed that this planet not only exists but inhabits a zone where its surface temperature could allow liquid water, a key ingredient for life on Earth. It is not yet known if this planet, Proxima b, has any life. Even if not, its potential ability to sustain liquid water might make it a good first hop for humanity's future trips out into the Milky Way Galaxy. Although the planet's parent star, Proxima Centauri, is cooler and redder than our Sun, one of the other two stars in the Alpha Centauri star system is very similar to our Sun. The featured image shows the sky location of Proxima Centauri in southern skies behind the telescope that made many of the discovery observations: ESO's 3.6-meter telescope in La Silla, Chile. The discovered planet orbits close in -- so close one year there takes only 11 days on Earth. The planet was discovered by the ESO's Pale Red Dot collaboration. Although seemingly unlikely, if Proxima b does have intelligent life, at 4.25 light years distance it is close enough to Earth for two-way communication. via NASA http://ift.tt/2carMtC

Curiosity at Murray Buttes on Mars Curiosity at Murray Buttes on Mars

What are these unusual lumps on Mars? As NASA's robotic Curiosity rover continues rolling across Mars, it is now approaching Murray Buttes. Several of the 15-meter high buttes are visible ahead in this horizontally compressed 360-degree across image taken inside Gale Crater earlier this month. The buttes are thought similar to Earth buttes in that they are capped with dense rock that is relatively resistant to erosion. In the image center is Curiosity's "arm" and "hand" used to examine rocks up close, drill into rocks, and collect samples. Curiosity has reached its four year anniversary on Mars and has been cleared to spend the next two years further exploring the slopes of Mount Sharp, the peak of which is the distant light-colored structure visible on the far left. via NASA http://ift.tt/2bglGC5

Tutulemma: Solar Eclipse Analemma Tutulemma: Solar Eclipse Analemma

If you went outside at exactly the same time every day and took a picture that included the Sun, how would the Sun's position change? With great planning and effort, such a series of images can be taken. The figure-8 path the Sun follows over the course of a year is called an analemma. At the Winter Solstice in Earth's northern hemisphere, the Sun appears at the bottom of the analemma. Analemmas created from different latitudes appear at least slightly different, as well as analemmas created at a different time each day. With even greater planning and effort, the series can include a total eclipse of the Sun as one of the images. Pictured is such a total solar eclipse analemma or Tutulemma - a term coined by the photographers based on the Turkish word for eclipse. The featured composite image sequence was recorded from Turkey starting in 2005. The base image for the sequence is from the total phase of a solar eclipse as viewed from Side, Turkey on 2006 March 29. Venus was also visible during totality, toward the lower right. If you want to create your own USA-based tutulemma ending at next August's total solar eclipse, now would be good time to start. via NASA http://ift.tt/2bwzRrA

Map of Total Solar Eclipse Path in 2017 August Map of Total Solar Eclipse Path in 2017 August

Would you like to see a total eclipse of the Sun? If so, do any friends or relatives live near the path of next summer's eclipse? If yes again, then you might want to arrange a visit for one year from today. Next year on this exact date, the path of a total solar eclipse will cut right across the center of the contiguous USA. All of North America and part of South America will experience, at the least, a partial solar eclipse. Featured here is a map of the path of totality, computed by eclipse expert Fred Espenak of NASA's GSFC. Many people who have seen a total solar eclipse tell stories about it for the rest of their lives. The last path of solar totality that included any part of the contiguous USA was in 1979, and the next two will be in 2024 and 2044. via NASA http://ift.tt/2bdhxQS

Perseid Fireball at Sunset Crater Perseid Fireball at Sunset Crater

On the night of August 12, this bright Perseid meteor flashed above volcanic Sunset Crater National Monument, Arizona, USA, planet Earth. Streaking along the summer Milky Way, its initial color is likely due to the shower meteor's characteristically high speed. Entering at 60 kilometers per second, Perseid meteors are capable of exciting green emission from oxygen atoms while passing through the tenuous atmosphere at high altitudes. Also characteristic of bright meteors, this Perseid left a visibly glowing persistent train. Its evolution is seen over a three minute sequence (left to right) spanning the bottom of the frame. The camera ultimately captured a dramatic timelapse video of the twisting, drifting train. via NASA http://ift.tt/2byQIpz

Five Planets and the Moon over Australia Five Planets and the Moon over Australia

It is not a coincidence that planets line up. That's because all of the planets orbit the Sun in (nearly) a single sheet called the plane of the ecliptic. When viewed from inside that plane -- as Earth dwellers are likely to do -- the planets all appear confined to a single band. It is a coincidence, though, when several of the brightest planets all appear in nearly the same direction. Such a coincidence was captured just last week. Featured above, six planets and Earth's Moon were all imaged together last week, just before sunset, from Mornington Peninsula in Victoria, Australia. A second band is visible across the top of this tall image -- the central band of our Milky Way Galaxy. via NASA http://ift.tt/2bClNx6

Human as Spaceship Human as Spaceship

You are a spaceship soaring through the universe. So is your dog. We all carry with us trillions of microorganisms as we go through life. These multitudes of bacteria, fungi, and archaea have different DNA than you. Collectively called your microbiome, your shipmates outnumber your own cells. Your crew members form communities, help digest food, engage in battles against intruders, and sometimes commute on a liquid superhighway from one end of your body to the other. Much of what your microbiome does, however, remains unknown. You are the captain, but being nice to your crew may allow you to explore more of your local cosmos. via NASA http://ift.tt/2aW739w