Yer a Wizard, Nebula

Located only 8,000 light years away, the Wizard nebula, surrounds developing open star cluster NGC 7380. Visually, the interplay of stars, gas, and dust has created a shape that appears to some like a medieval sorcerer which spans about 100 light years. Astronomers expect that the nebula may only last a few million years, although some of the stars being formed may outlive our Sun.

(Image Credit: J-P Metsavainio)

New Horizons Zooms Past Neptune on 25th Anniversary of Voyager 2

25 years ago today Voyager 2 made the only close approach to Neptune, coming within 3,000 miles of the blue gas giant. At the time of the flyby, the spacecraft captured this incredible image of the planet’s southern hemisphere. Two dark spots are visible: an Earth-sized Great Dark Spot located on the far left, and Dark Spot 2 located near bottom. A bright cloud dubbed “Scooter” accompanies the Great Dark Spot. Recent computer simulations indicate that scooters are methane clouds that might commonly be found near dark spots.

In what one NASA official dubbed as a “cosmic coincidence”, the New Horizons spacecraft passed through Neptune’s orbit today on its way to its intended destination of Pluto. Launched in 2006, New Horizons is the fastest spacecraft ever launched and will be the first probe to reach Pluto. Little is known about the dwarf planet. It’s so dim and far away that the best photos by NASA’s powerful Hubble Space Telescope show Pluto as a blur of pixels. It is scheduled to arrive at Pluto on July 14, 2015 and many incredible discoveries await.


Searching for Life in Our Solar System


Scientists expect that Europa may have more liquid water than in all of Earth’s oceans. It has all the elements thought to be key for the origin of life: water, energy, and organic chemicals, the carbon-containing building blocks of life. Unlike Earth though, Europa’s vast, salty seas lie beneath roughly 10 miles of ice. Not only is it difficult to get a probe beneath this icy armor, but Europa’s oceans are darker than a cave — which means photosynthesis won’t work. However, something down there may subsist on geothermal heat or complex molecules from the surface.

NASA says it’s setting aside $25 million for designing scientific instruments to address questions about the habitability of Europa, an ice-covered moon of Jupiter. A Europa probe that could be launched in the 2020s.

Titan is Saturn’s largest moon and the only world in the solar system (besides Earth) known to sport liquid lakes. These are lakes of ethane and methane — liquid natural gas — endlessly topped up by hydrocarbon rain. Despite the odd ingredients and Titan’s extremely cold temperatures (minus 290 Fahrenheit, or minus 179 Celsius), it is a world where chemistry’s a happening enterprise. It’s so cold that water ice is rock-hard—in fact, the rocks littering the moon’s surface are made from water. Water is everywhere on Titan, but it’s locked in a state that’s inaccessible for life-sustaining chemistries. On Titan, scientists would most likely be looking for bizarre life. Life that, instead of being water-based, uses liquid hydrocarbons as a solvent. Yet if life is found, it could demonstrate a different way in which it could begin and populate the cosmos.

Like its more celebrated neighbor Europa, scientists suggest that Callisto’s interior contains a salty ocean separated by ice layers, with a rocky seafloor underlying everything. The likely presence of an ocean within Callisto leaves open the possibility that it could sustain life. Because of its low radiation levels, Callisto has long been considered a suitable place among the Galilean moons for future exploration.

The largest moon in the solar system, Ganymede, may feature liquid oceans layered between vast sheets of ice. Studies suggest that there may be a layer of salty water directly on top of Ganymede’s rocky core. Chemical interactions between rock and water could lead to the formation of life.

Venus, with its scorching surface temperatures (850 F, or 454 C). The planet is generally assumed to be unlivable but some scientists believe that high in the Venusian atmosphere where temperatures are more tolerable atmospheric sulfur dioxide and carbon monoxide might serve as food for floating microbes.

Mars remains popular for those hunting for otherworldly life. In 2013, scientists identified sulfur, nitrogen, hydrogen, oxygen, phosphorus and carbon - some of the key chemical ingredients for life - in the powder Curiosity drilled out of a sedimentary rock near an ancient stream bed in Gale Crater. Also, particularly intriguing are the dark stripes that appear in the Martian summertime at Horowitz crater. These are likely to be salty meltwater only inches beneath Mars’ dusty top layer.

In 2005, NASA’s Cassini spacecraft photographed geysers of frozen water spewing from cracks in Enceladus’ southern hemisphere. Scientists think reservoirs of liquid water lie beneath the frozen surface and are warmed by gravitational interactions between Enceladus and other moons around Saturn.

(Credit: List compiled from “6 Most Likely Places for Alien Life in the Solar System”)

I Zwicky 18 is a dwarf irregular galaxy located about 59 million light years away. The galaxy’s remote distance has made it difficult for astronomers to detect older, fainter stars within the galaxy which are at the limit of Hubble’s resolution and sensitivity. 

(Image Credit: HST/NASA/ESA)

The Colliding of Cosmic Winds

This is a beautiful and ethereal display of a “bow shock” about a half a light year across in the Orion Nebula. A bow shock is created in space when two streams of gas collide. In this image, the young star L.L. Orionis emits a solar wind ­– a stream of charged particles moving rapidly outward from the star. As the fast stellar wind runs into slow moving gas from the surrounding Orion Nebula a shock front is formed, similar to the bow wave of a boat moving through water or a plane traveling at supersonic speed.

(Image Credit: NASA and The Hubble Heritage Team, C. R. O’Dell, Vanderbilt University)


The photos Cassini has been sending back go beyond science. They are art.

In this image, Titan can be seen behind Saturn’s rings with Enceladus peaking onto the crescent. The bright surrounding ring is atmospheric haze above Titan, gas that is scattering sunlight to a camera operating onboard the robotic Cassini spacecraft. Since the image was taken pointing nearly at the Sun, the surfaces of Titan and Enceladus appear in silhouette, and the rings of Saturn appear similar to a photographic negative.

(Image Credit: Cassini Imaging Team, SSI, JPL, ESA, NASA)

Richard Feynman on the value of science..

"The same thrill, the same awe and mystery, comes again and again when we look at any question deeply enough.  With more knowledge comes a deeper, more wonderful mystery, luring one on to penetrate deeper still.  Never concerned that the answer may prove disappointing, with pleasure and confidence we turn over each new stone to find unimagined strangeness leading on to more wonderful questions and mysteries - certainly a grand adventure!"

Background image credit: Michael Sidonio

"To fly in space is to see the reality of Earth, alone. The experience changed my life and my attitude toward life itself. I am one of the lucky ones." — Astronaut Roberta Bondar

Astronaut Ron Garan was one of the lucky ones when he caught a Perseid meteor from the ISS back in 2011. Orbiting at an altitude of about 380 km, the Perseid meteors streak, swept up dust left from comet Swift-Tuttle. The glowing comet dust grains are traveling at about 60 km per second through the denser atmosphere around 100 km above Earth’s surface.


Astronomy Photo of the Day (APotD): 8/08/14 - The Lagoon Nebula

Here is another spectacular picture of the Lagoon Nebula, a region stretching over 100 light-years across, approximately 4,000 to 5,000 light-years from Earth in the Sagittarius constellation.
This cosmic area is vast and beautiful, with the gas and dust clouds condensing and forming millions of massive newborn stars. The ultraviolet radiation emitted from the stars sculpts the gas and dust into the unusual shape you see in the attached image. The most giant of the embedded stars is responsible for illuminating the brightest part of the nebula, which is in the center of the image. The spiraling funnel-esque shape has its own classification — the Hourglass nebula.


Image Credit: ESO/IDA/Danish 1.5 m/ R. Gendler, U.G. Jørgensen, K. Harpsøe

Close-up of the comet taken on August 6. The image shows the comet’s ‘head’ at the left of the frame, which is casting shadow onto the ‘neck’ and ‘body' at right. Distance to comet: 75 miles.


Satellite Meets Comet In Historic Rendezvous

This is a comet named 67P/Churyumov-Gerasimenko. A satellite called Rosetta rendezvoused with it today, Aug. 6, after traveling 4 billion miles for more than 10 years.

The European Space Agency craft now sits 62 miles from the icy 2.5-mile-long comet (see a visualization of the mission here) about midway between Mars and Jupiter. The two will travel together on the comet’s orbit as it approaches the sun. 

Rosetta, which also includes a number of NASA instruments, will for the first time in history study a comet up close, put a lander on the surface and monitor changes as it approaches the sun. Among other science to be done, the craft’s Philae lander will drill almost 8 inches into 67P, another first. 

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IC 4499: A globular cluster’s age revisited

This new NASA/ESA Hubble Space Telescope image shows the globular cluster IC 4499. Globular clusters are big balls of old stars that orbit around their host galaxy. It has long been believed that all the stars within a globular cluster form at the about same time, a property which can be used to determine the cluster’s age. For more massive globulars however, detailed observations have shown that this is not entirely true — there is evidence that they instead consist of multiple populations of stars born at different times. One of the driving forces behind this behaviour is thought to be gravity: more massive globulars manage to grab more gas and dust, which can then be transformed into new stars.

IC 4499 is a somewhat special case. Its mass lies somewhere between low-mass globulars, which show a single generation build-up, and the more complex and massive globulars which can contain more than one generation of stars. By studying objects like IC 4499 astronomers can therefore explore how mass affects a cluster’s contents. Astronomers found no sign of multiple generations of stars in IC 4499 — supporting the idea that less massive clusters in general only consist of a single stellar generation.

Hubble observations of IC 4499 have also helped to pinpoint the cluster’s age: observations of this cluster from the 1990s suggested a puzzlingly young age when compared to other globular clusters within the Milky Way. However, since those first estimates new Hubble data been obtained, and it has been found to be much more likely that IC 4499 is actually roughly the same age as other Milky Way clusters at approximately 12 billion years old.

Image credit: ESA/Hubble & NASA