Gas Outflow From Sculptor Galaxy (NGC 253) Hints At Scarcity Of High Mass Galaxies

This comparison picture of the nearby bright spiral galaxy NGC 253, also known as the Sculptor Galaxy, shows the infrared view from ESO’s VISTA Telescope (left) and a detailed new view of the cool gas outflows at millimetre wavelengths from ALMA (right).
Credit:ESO/ALMA (ESO/NAOJ/NRAO)/J. Emerson/VISTA

The Atacama Large Millimeter/submillimeter Array (ALMA) have observed massive molecular gas outflows ejected by the Sculptor Galaxy (NGC 253). This may explain how starburst galaxies behave and why there is a scarcity of very massive galaxies in the Universe.

Starburst galaxies are galaxies that have a very high rate of star formation compared to regular galaxies. They produce stars so fast that their available gas content is depleted in a shorter time span. Starburst galaxies like the Sculptor Galaxy are defined by the rate at which they convert gas into stars, the available quantity of gas available, and the timescale on which SFR (star formation rate) will consume the available gas with the age or rotation period of the galaxy.

With the available data supplied by ALMA, scientist can study and explain why there are so few massive galaxies around. And if the ejected gas theory holds true for most of these galaxies, they also want to find out what ultimately happens to to these gas outflows.

Black Hole Outflow From Galaxy NGC 3783 Surprises Observers

The VLTI (Very Large Telescope Interferometer) of the European Southern Observatory has observed that dust around a black hole at the NGC 3783 galaxy forms a cool wind that streams out from the black hole. This observation have surprised scientists since dust surrounding black holes have been observed to reach 700 to 1000 degrees Celsius.

The dust can be found at the torus of the black hole. The torus, which resembles a three dimensional donut (as seen on the image on the left), surrounds the black hole and is believed to be the source of high energy objects called active galactic nuclei (AGN). The supermassive black hole pulls in material from the surrounding region but it seems that the resulting radiation and energy that this produces also blows it away.

The hotter dust was mapped using the AMBER VLTI instrument at near-infrared wavelengths and the newer observations reported here used the MIDI instrument at wavelengths between 8 and 13 microns in the mid-infrared.

Black holes are regions in space where gravity is so strong that even light cannot escape its pull. Black holes are formed from stars that have exploded into a supernova and collapses into itself.

Black holes vary in size with some being 20 times more massive that the sun. Supermassive Black holes can reach a mass more than a million times than that of the Sun. Each galaxy has a supermassive black hole in its center.

The VLTI used to observe the black hole is made up of a combination of four VLT Unit Telescopes and four moveable 1.8-metre VLT Auxiliary Telescopes. It combines the light from several of these telescopes to form one observation through a process called interferometry. This process does not actually produce images but the generated measurements can be used to increase the level of detail of resulting observations.

Galaxy Sized Cloud of Hydrogen Gas Discovered in Supposedly Empty Region of Space

Hydrogen clouds the size of a dwarf galaxy have been discovered by the Green Bank Telescope between two galaxies (Andromeda -M31 and Triangulum -M33). M31 is at the upper right while M33 is at the bottom left. This high resolution image was captured by the GBT and combined with the image of two galaxies to give it some perspective.
Credit: Bill Saxton, NRAO/AUI/NSF

Astronomers at the Green Bank Telescope (GBT) have discovered a huge cloud of hydrogen gas in a region of space that is supposedly empty of matter. Scientists are studying the object as the source of the gas is still unknown.

The cloud is unusual since the size is as big as a small dwarf galaxy and is moving at a speed comparable to its two nearest galaxy neighbors, Andromeda (M31) and Triangulum (M33). It is also believed that a dark matter filament is responsible for giving the cloud a gravitational structure that keeps it together.

Dark matter is a type of matter that is believed to account for 84.5% of the total matter in the universe. Dark matter cannot be seen or observed directly as it does not absorb light or any other type of radiation.

Although it is too early to tell if this cloud is a new object or feature, clouds of gas and dust in space are called nebulas. Nebulas are regions in space where stars are formed from the gas and clouds. The discovered cloud of hydrogen gas is not a star forming region.

It is theorized that the gas may one day fall into either of the two galaxies and initiate the process of forming new stars.

Star Forming Molecular Cloud Lupus 3 Captured In Amazing Detail

Most interstellar clouds of dust and gas are where stars are formed. The surrounding matter start to form large masses which will eventually become stars. Planets and other objects are also formed within these regions. Clouds like Lupus 3 are called 'dark clouds' or 'molecular clouds'.

A molecular cloud is a type of star forming region where molecules, most commonly molecular hydrogen (H₂), are formed. The stars formed in the image are called Herbig Ae/Be stars (named after astronomer George Howard Herbig).

Herbig Ae/Be stars are still in their star forming space and are not yet burning hydrogen for fuel. Instead, they shine by converting gravitational potential energy into heat as they contract.

Study Finds Sleep Patterns And Neurobehavioral Effects As A Concern On Manned Mission To Mars

Researchers analyzing data on the the sleep, performance, and mood behavioral impact of deep space travel to astronauts find that sleep patterns and neurobehavioral effects on the crew members must be addressed for successful adaption to prolonged space missions.

For quite some time, Mars has been a hot topic when it comes to sending humans into outer space. Just recently, NASA's Mars Curiosity Rover landed on Mars and have been taking tests of the surface of the planet. It has even picked up what might possibly be evidence of water on Mars.

Travelling to Mars takes lots of preparation. For one, there are only four windows of opportunity that cycles every fifteen years to require the least amount of energy to transfer from an Earth orbit to the Mars orbit.

The next window for a low energy orbit transfer would occur in 2018.

It would take roughly 250 days to travel from the Earth to Mars. During the trip, astronauts are exposed to dangerous cosmic radiation, space debris, a zero gravity environment and even psychological effects from prolonged isolation.

The United States delayed its plan to send astronauts to Mars by 2020. Instead, the plan is to send a manned mission to an asteroid in 2025 and plan for a Mars trip by 2030.

Mars One, a private endeavor to set up a human colony on Mars led by Dutch entrepreneur, Bas Lansdorp, was announced on June 2012. The project's plan is to land humans on Mars to establish a permanent settlement in 2023. A new set of four astronauts would then arrive every two years.

Mars One is set up to be a one way trip to Mars for the astronauts.

Space Food 101 - Spirulina

Ever wonder what astronauts eat when they’re hovering thousands of miles above the Earth?

In space, there are no fast food burger joints, deli shops, or even a side street hotdog stand. Although enjoying a gourmet meal in outer space with the Earth as a backdrop sounds exciting, it isn’t possible.

Before you think of space food as being eaten out of toothpaste tubes or little bouillon cubes, think again. We’re in the 21st century now. Astronauts have a very discriminating palette.

The space shuttles do not have refrigerators so food must be safe to store at room temperature for a year and should last around a year and a half. To adjust to these conditions, food is dehydrated, vacuum packed and freeze dried. Just add water, wait a few minutes, and it’s good to go.

Aside from allaying hunger, space food’s main priority is to provide the correct and proper nutrition a growing astronaut needs.

One major supplement is Spirulina. NASA and ESA have both proposed cultivating it as one of the primary foods for deep space travel and long-term space missions.

Spirulina are free-floating filamentous cyanobacteria characterized by cylindrical, multi-cellular trichomes in an open left-hand helix. In layman’s terms, Spirulina is an algae. A blue green moss found near lakes and under rocks.

Spirulina contains 3 to 4 times rich vegetable protein than fish or beef. It also has a high volume of beta-carotene for cell protection, gamma-Linolein acid to prevent cholesterol and prevent heart disease, and a good dose of multi vitamins and minerals.

Wired Science Presents Best Space Photos of 2012

The Flame Nebula

For the past year, Wired has been featuring amazing and breathtaking photographs of space and everything in it. Wired Science Space Photo of the Day has shown around 240 pictures since it started the section in February 2012.

Now, Wired has chosen 18 photographs and named it the best space photographs from the collection. The photographs features amazing epic photographs like the The Flame Nebula (pictured above) to the Cookie Monster crater in Mercury and even the Blue Dunes of Mars.

The space images have been sourced from space organizations like NASA, ESO, and ESA, and the quality and resolution are absolutely top notch. Some of the images have even been shown here in Quantum Day since Quantum Day is recognized as Press for ESO, ESA, and Hubble Space Telescope.

Check out the link below to visit the site.

ESO Installs Supercomputer At ALMA Facility - The ALMA Correlator

The ALMA correlator

One of the fastest supercomuter, the ALMA correlator, has been fully installed and tested at the ALMA astronomical facility in Chile. With over 134 million processors and performance up to 17 quadrillion operations per second, the ALMA correlator is one of the fastest supercomputers in existence today.

The Atacama Large Millimeter /submillimeter Array (ALMA) is a space telescope located on the Chajnantor plateau in the Chilean Andes. It has 66 high-precision antennas, spread over distances of up to 16 kilometres. The facility is partially operational and will be fully completed by March 2013.

ALMA studies light emitted by some of the coldest objects in space. Since these objects emit light that is hardly detected, the ALMA looks at wavelengths between infrared light and radio waves. This is known as millimeter and submillimeter radiation. The telescope can detect light emitted by objects that are a few degrees above absolute zero.

The space telescope can help astronomers study the chemical and physical conditions in molecular clouds where stars are produced. These clouds are made up of dense gas and dust which are dark and obscured in visible light, much like clouds in the sky are. By detecting the light emitted in near infrared, ALMA can detect and collect data from these objects.

With the installation of the ALMA correlator, it will increase the sensitivity and image quality of its observation of outer space.

Planet Floating Freely Through Space Without An Orbit Discovered

The Very Large Telescope (VLT) of the European Southern Observatory (ESO) and the Canada-France-Hawaii Telescope have discovered a planet that is freely wandering through space. It has no orbit nor a star attached to it. This planet free-floating planet is labeled CFBDSIR2149 and also referred to as CFBDSIR J214947.2-040308.9.

Free-floating planets are objects in space that are not paired up or connected to a star. They roam the universe without a predetermined orbit since there is no star to supply the gravity to put them in their place.

Defending The Earth Against Incoming Asteroids Using Paintballs

An MIT graduate student proposes covering Earth bound asteroids with paint using paint pellets and paint balls to deflect its trajectory from hitting our planet.

The Earth has always been in danger of being hit by large space objects such as comets and asteroids. The extinction of the dinosaurs 65 million years ago, is said to have been caused by an asteroid ten to fifteen kilometers wide hitting the Earth.

According to Nick Bostrom who did a study on human extinction scenarios and its related hazards, every 500,000 years, an asteroid 1km in diameter strikes the earth and a 5km asteroid every ten million years. To get an idea on how powerful asteroids of this size are, a five to ten meter asteroid packs as much power as an atomic bomb.

Apophis

Asteroid 2004 MN4 known as Apophis has a diameter of 270 meters and weighs around 27 gigatons. One gigaton is one billion tons (1x10⁹). According to its present trajectory, Apophis will have a close call with the Earth on Friday, 13 April 2029.

NASA Spacecraft New Horizons May Be In Peril As It Nears Pluto

The Kuiper belt is a is a region of the Solar System beyond the planets, extending from the orbit of Neptune at 30 Astronomical Units (AU) to approximately 50 AU from the Sun. 1 AU is exactly 149,597,870,700 meters (92,955,807.273 miles). This is the distance from the Earth to the Sun.

The Kuiper belt is similar to the asteroid belt although 20 times widers and twenty to two hundred times more massive. Within the belt are small bodies and left overs from when the Solar system was forming. Kuiper belt objects are composed largely of frozen volatiles (termed "ices"), such as methane, ammonia and water.

Within the belt lies the newly reclassified dwarf planet, Pluto. Pluto is composed primarily of rock and ice. It is about approximately one-sixth the mass of the Earth's Moon and one-third its volume. Five moons have been discovered orbiting the dwarf planet.

Scientists Believe Super-Earth Planet 55 Cancri e May Be Covered With Diamonds

On August 30, 2004, astronomers discovered a planet 40 light years away orbiting a sun-like star.

The planet, named 55 Cancri e has half the mass of Neptune, almost 8 times more of the Earth. It is twice the width of the Earth classifying it as the first discovered Super-Earth.

Super Earth planets are more massive than the Earth but lighter than gas giants like Neptune. They can be made up of gas, rock or both. To date, there are around 70 discovered super-earth like planets with hundreds more waiting to be classified.

The planet, 55 Cancri e, orbits the star 55 Cancri A. It is the innermost planet in its planetary system, orbiting 55 Cancri A twenty-six times closer than that of Mercury to the Sun. It takes the planet eighteen hours for it to orbit the star.

Because of the proximity of 55 Cancri e to 55 Cancri A, temperatures of the planet when facing the star reaches more than 2,000 Kelvin or 3,140 Fahrenheit. This is hot enough to melt metal.

Several theories abound on the composition of the planet. An observation by the Spitzer Space Telescope suggests that 20% of the planet may be comprised of light elements and compounds, including water.

They believe that the water exists in both liquid and gas called a supercritical state. And that the whole planet is blanketed by steam. Since hydrogen has yet to be observed from the planet, it could be that instead of water, the compound could be made up of carbon dioxide.

Nearby super-Earth likely a diamond planet

New research led by Yale University scientists suggests that a rocky planet twice Earth's size orbiting a nearby star is a diamond planet.

"This is our first glimpse of a rocky world with a fundamentally different chemistry from Earth," said lead researcher Nikku Madhusudhan, a Yale postdoctoral researcher in physics and astronomy. "The surface of this planet is likely covered in graphite and diamond rather than water and granite."

ESO News: Two Contests To Commemorate 50th Anniversary of ESO - Choose What The VLT Observes Or Visit The VLT

ESO builds and operates some of the most advanced telescopes on Earth including the Very Large Telescope (VLT) at the Paranal Observatory. These huge machines have made many fascinating discoveries about the Universe. Now, for the first time in its history, you can decide what to observe with the VLT, or even win an amazing trip to Chile’s breathtaking Atacama Desert to help make the observations yourself.

The first of our two anniversary competitions is called Choose What the VLT Observes.

Usually, astronomers have to prepare a detailed plan long in advance, describing why they want to use the VLT, and only a small fraction of them are given the chance. But for you, it’s going to be rather easier.

ESO has already pre-selected some interesting celestial objects that are visible in the sky on the 50th anniversary of ESO — 5 October 2012 — and fit in VLT’s field of view [1]. All you need to do is cast your vote for the object you like most. The one that gets the most votes will be observed using the VLT on the 50th anniversary day.

We will draw a winner and ten runners up from among those who voted (you do not have to have voted for the winning object). The winner will receive one of the latest iPads and the runners up will receive ESO products including books, DVDs and other goodies.

Next, what about visiting the VLT to help make the observations of the winning object yourself?

Carbonaceous chondrites and Asteroids Most Likely Source of the Earth's Water

The Allende meteorite is the largest carbonaceous chondrite ever found on Earth.

Chondrites are meteorites that have not been tampered or modified due to melting or differentiation of the parent body. These type of meteorites form when various types of dust and small grains that were present in the early solar system gradually accumulate to form primitive asteroids.

Chondrites should not be confused with Chondrodite which is a rare nesosilicate mineral.

A class of chondritic meteorites are Carbonaceous chondrites or C chondrites. These comprise at least 7 known groups of meteorites and other ungrouped meteorites. Only 4.6% of meteorite falling to Earth are Carbonaceous chondrites

Solar system ice: Source of Earth's water

Scientists have long believed that comets and, or a type of very primitive meteorite called carbonaceous chondrites were the sources of early Earth's volatile elements—which include hydrogen, nitrogen, and carbon—and possibly organic material, too. Understanding where these volatiles came from is crucial for determining the origins of both water and life on the planet. New research led by Carnegie's Conel Alexander focuses on frozen water that was distributed throughout much of the early Solar System, but probably not in the materials that aggregated to initially form Earth.

The evidence for this ice is now preserved in objects like comets and water-bearing carbonaceous chondrites. The team's findings contradict prevailing theories about the relationship between these two types of bodies and suggest that meteorites, and their parent asteroids, are the most-likely sources of the Earth's water. Their work is published July 12 by Science Express.

Looking at the ratio of hydrogen to its heavy isotope deuterium in frozen water (H2O), scientists can get an idea of the relative distance from the Sun at which objects containing the water were formed. Objects that formed farther out should generally have higher deuterium content in their ice than objects that formed closer to the Sun, and objects that formed in the same regions should have similar hydrogen isotopic compositions. Therefore, by comparing the deuterium content of water in carbonaceous chondrites to the deuterium content of comets, it is possible to tell if they formed in similar reaches of the Solar System.

Possible Visual Evidence of a Dark Galaxy Spotted By VLT

A dark galaxy is believed to be an invisible galaxy composed of dark matter. The existence of a dark galaxy is still a hypothesis.

The theory of the existence of a dark galaxy came up upon observing galaxy NGC 4254. It was observed that this galaxy collided with another galaxy because of the presence of gas being siphoned away into a tenuous stream, and one of its spiral arms is being stretched out. There is no evidence of another galaxy involved in the collision which brought up the theory of dark galaxies.

Dark galaxies have no detectable stars and are believed to be invisible to the known visual spectrums. There is experimental evidence to support the existence of dark galaxies, although scientists have no conclusive evidence and continue their research. Scientists have proposed a means to track down the dark dwarf galaxies that should be orbiting the Milky Way, saying they have now found evidence of one.

For the first time, dark galaxies — an early phase of galaxy formation, predicted by theory but unobserved until now — may have been spotted. These objects are essentially gas-rich galaxies without stars. Using ESO’s Very Large Telescope, an international team thinks they have detected these elusive objects by observing them glowing as they are illuminated by a quasar.

Dark Galaxies of the Early Universe Spotted for the First Time

Dark galaxies are small, gas-rich galaxies in the early Universe that are very inefficient at forming stars. They are predicted by theories of galaxy formation and are thought to be the building blocks of today’s bright, star-filled galaxies. Astronomers think that they may have fed large galaxies with much of the gas that later formed into the stars that exist today.

Because they are essentially devoid of stars, these dark galaxies don’t emit much light, making them very hard to detect. For years astronomers have been trying to develop new techniques that could confirm the existence of these galaxies. Small absorption dips in the spectra of background sources of light have hinted at their existence. However, this new study marks the first time that such objects have been seen directly.

“Our approach to the problem of detecting a dark galaxy was simply to shine a bright light on it.” explains Simon Lilly (ETH Zurich, Switzerland), co-author of the paper. “We searched for the fluorescent glow of the gas in dark galaxies when they are illuminated by the ultraviolet light from a nearby and very bright quasar. The light from the quasar makes the dark galaxies light up in a process similar to how white clothes are illuminated by ultraviolet lamps in a night club.”^[1]

Astronomers Can Now Study Atmosphere of Exoplanet Tau Boötis b

Wide-field view of the parent star (Tau Boötis) of exoplanet Tau Boötis b

With billions of stars out in the Universe, the chances of a planet orbiting a star just like the Earth orbiting the Sun is very high. Some astronomers believe that 50% of stars similar to the sun harbor at least one orbiting planet.

In a 2012 study by the Paris Institute of Astrophysics, they suggest that each star of the 100 billion or so in our Milky Way galaxy is estimated to host "on average ... at least 1.6 planets." This translates to at least 160 billion star bound exoplanets just in the Milky Way Galaxy alone.

A planet that is located outside of the Solar System is called an extrasolar planet. It is more popularly called an exoplanet. There are currently over 3000 discovered exoplanets in deep space. 779 of these have already been identified. The remaining exoplanets are still being observed by the astronomers and scientists for exoplanet confirmation.

New Way of Probing Exoplanet Atmospheres

The planet Tau Boötis b^[1] was one of the first exoplanets to be discovered back in 1996, and it is still one of the closest exoplanets known. Although its parent star is easily visible with the naked eye, the planet itself certainly is not, and up to now it could only be detected by its gravitational effects on the star. Tau Boötis b is a large “hot Jupiter” planet orbiting very close to its parent star.

For the first time a clever new technique has allowed astronomers to study the atmosphere of an exoplanet in detail — even though it does not pass in front of its parent star. An international team has used ESO’s Very Large Telescope to directly catch the faint glow from the planet Tau Boötis b. They have studied the planet’s atmosphere and measured its orbit and mass precisely for the first time — in the process solving a 15-year old problem. Surprisingly, the team also finds that the planet’s atmosphere seems to be cooler higher up, the opposite of what was expected. The results will be published in the 28 June 2012 issue of the journal Nature.

Like most exoplanets, this planet does not transit the disc of its star (like the recent transit of Venus). Up to now such transits were essential to allow the study of hot Jupiter atmospheres: when a planet passes in front of its star it imprints the properties of the atmosphere onto the starlight. As no starlight shines through Tau Boötis b’s atmosphere towards us, this means the planet’s atmosphere could not be studied before.

But now, after 15 years of attempting to study the faint glow that is emitted from hot Jupiter exoplanets, astronomers have finally succeeded in reliably probing the structure of the atmosphere of Tau Boötis b and deducing its mass accurately for the first time. The team used the CRIRES^[2] instrument on the Very Large Telescope (VLT) at ESO’s Paranal Observatory in Chile. They combined high quality infrared observations (at wavelengths around 2.3 microns)^[3] with a clever new trick to tease out the weak signal of the planet from the much stronger one from the parent star^[4].

Lead author of the study Matteo Brogi (Leiden Observatory, the Netherlands) explains: “Thanks to the high quality observations provided by the VLT and CRIRES we were able to study the spectrum of the system in much more detail than has been possible before. Only about 0.01% of the light we see comes from the planet, and the rest from the star, so this was not easy”.

Astrophysicist Researches Into The Requirements of Planetary Formation

New research shows that planets up to four times the size of the Earth can form around very different stars -- including stars that are poorer in heavy elements.
Credit: MediaFarm / Niels Bohr Institute

There are billions of stars in the Universe. And the probability of a planet orbiting one just like the Earth orbiting the Sun is very high. There are suggestions that 50% of stars similar to the sun harbor at least one orbiting planet.

A planet that is located outside of the Solar System is called an extrasolar planet or exoplanet. To date, there are over 3000 discovered exoplanets, 779 of these have been identified. The remaining 2300+ are being observed by the Kepler space telescope for confirmation.

In a 2012 study by the Paris Institute of Astrophysics, they suggest that each star of the 100 billion or so in our Milky Way galaxy is estimated to host "on average ... at least 1.6 planets." This translates to at least 160 billion star bound exoplanets just in the Milky Way Galaxy alone.

Planets can form around different types of stars

It had previously been thought that planets were more likely to form around a star if the star had a high content of heavier elements. But new research from the University of Copenhagen, among others, shows that small planets can form around very different types of stars – also stars that are relatively poor in heavy elements. This significantly increases the likelihood that Earth-like planets are widespread in the universe. The results have been published in the prestigious scientific journal, Nature.

3,000 exoplanets, i.e. planets orbiting a star other than the Sun, have now been discovered. 2,300 of these potential planets are being observed with the Kepler Satellite by measuring the brightness of the host stars. If a planet moves in front of its star, there is a small decrease in the brightness and if this happens repeatedly, it could be a planet orbiting the star and dimming its light.

The Reflection Nova Messier 78 and the Atacama Pathfinder Experiment telescope (APEX)

APEX Telescope in Chile

The Atacama Pathfinder Experiment telescope (APEX) is a 12 meter diameter telescope. Operated by the European Southern Observatory (ESO), the telescope operates at millimeter and sub-millimeter wavelengths which are wavelengths between infrared light and radio waves.

The APEX telescope is situated at the Chajnantor plateau in the Atacama region of Chile. With an elevation of 5100 meters (3.17 miles), it is one of the highest observatory sites on Earth.

APEX is a 12-metre diameter telescope, operating at millimetre and submillimetre wavelengths — between infrared light and radio waves. Submillimetre astronomy opens a window into the cold, dusty and distant Universe, but the faint signals from space are heavily absorbed by water vapour in the Earth's atmosphere. Chajnantor is an ideal location for such a telescope, as the region is one of the driest on the planet and is more than 750 m higher than the observatories on Mauna Kea, and 2400 m higher than the Very Large Telescope (VLT) on Cerro Paranal.

APEX is a collaboration between the Max Planck Institute for Radio Astronomy (MPIfR), the Onsala Space Observatory (OSO) and ESO. Operation of APEX at Chajnantor is entrusted to ESO. APEX is a pathfinder for the next-generation submillimetre telescope, the Atacama Large Millimeter/submillimeter Array (ALMA), which is being built and operated on the same plateau.

Messier 78

In the constellation of Orion, 1350 light years away, lies the reflection nebula, Messier 78. Reflection nebulas (nebulae) are clouds of dust which reflect the light of a nearby star or stars. Messier 78 is a fine example of a reflection nebula.

The nebula Messier 78 takes centre stage in this image taken with the Wide Field Imager on the MPG/ESO 2.2-metre telescope at the La Silla Observatory in Chile, while the stars powering the bright display take a backseat. The brilliant starlight ricochets off dust particles in the nebula, illuminating it with scattered blue light. Igor Chekalin was the overall winner of ESO’s Hidden Treasures 2010 astrophotography competition with his image of this stunning object.
Photo: ESO

NASA Flight Surgeons - Ensuring the Health and Safety of Astronauts

Astronauts on space missions have lots of responsibility. They are tasked to work with million dollar equipment and do complicated scientific experiments.

They have to make sure that they are alert and healthy facing the rigors of space.

An astronaut cannot afford being sick during a space mission. When an astronaut faces health concerns, he or she may be reassigned somewhere else or even "grounded". And in space, even the slightest health concern may jeopardize the mission and the whole crew.

NASA Flight surgeons are there to ensure that this happens as rarely as possible or not at all. Astronauts are a very rare breed and a prime specimen. They go to rigorous and extensive training, taught highly specialized skills, and have millions invested in their expertise, and it is in NASA's best interest not to replace them.

Sean Roden, NASA Flight Surgeon explains, "It's the job of the flight surgeons to keep everyone on flight status," he said. "We have such a unique patient population with such unique skills. We try to keep everybody flying. We just don't ground very many people..."

In the video, NASA Flight Surgeon Ed Powers discusses how flight doctors work with crew members on board the station to keep the astronauts healthy. Powers also discusses the complications in diagnosing patients from far away in space as well as the effect of space medicine to life here on earth.

Studying The Gravitational Field of Mars Moon Phobos

The Mars moon, Phobos is of interest to astronomers. The Potato-shaped moon is thought to be an asteroid that got caught by the gravity of Mars. Some think that it may be a collection of rocks that formed around Mars after its formation.

It is one of two moons at Mars (the other being Deimos) and has an extremely low density may mean that it has many interior voids.

Phobos is the larger and closer of the two natural satellites of Mars. Despite decades of Martian exploration, little is known about Phobos. Many fundamental properties of this small potato-shaped body stay vague, for example, its gravitational field. SHI Xian and coauthors from Shanghai Astronomical Observatory and Technical University Berlin recently updated working models for the gravitational field of Phobos. Their work, entitled "Working models for the gravitational field of Phobos", was published in SCIENCE CHINA Physics, Mechanics & Astronomy, 2012, Vol 55(2).

Mars has two natural satellites, Phobos and Deimos. Unlike the Earth's Moon, the Martian moons are relatively small in size and irregularly shaped. Different scenarios have been suggested for the origin of these two bodies, such as captured asteroids or reaccreted ejectas from an impact event on Mars. However, none of the origin theories has yet been confirmed. To unveil the mysteries of the Martian moons, scientists need more detailed understandings of their physical properties, among which the gravitational field is of great importance. Existing gravitational field models of Phobos are all based on early shape models with relatively low resolution and precision. Since 2003, ESA's Mars Express (MEX) probe has been orbiting Mars in an elliptical polar orbit. This special orbit allows it to perform regular flybys of Phobos, during which plenty of high-quality imaging data are accumulated. These data have helped establish a new, high-resolution shape model of Phobos. This provides a good opportunity to improve the gravitational field model.