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NASA Plans to Capture Asteroid In Moon’s Orbit

Photo credit: NASA/AMA

Photo credit: NASA/AMA

As part of the Asteroid Redirect Mission (ARM), NASA and cooperative scientists have been searching for a suitable asteroid to capture and redirect into the moon’s orbit for continual research. The ARM spacecraft is proposed to launch in 2019. Once set in orbit, the hands-on examination of the asteroid will begin in the 2020s. The mission has two main focuses: to develop the expertise needed for deep space travel to Mars and beyond, as well as providing an opportunity to test technologies that will keep Earth safe from any possible future asteroid impacts.

There are two concepts set for NASA’s ARM operation: “The first is to fully capture a very small asteroid in open space, and the second is to collect a boulder-sized sample off of a much larger asteroid. Both concepts would require redirecting an asteroid less than 32 feet (10 meters) in size into the moon’s orbit. The agency will choose between these two concepts in late 2014 and further refine the mission’s design.”

Recently a $4.9 million award has been offered for concept studies that will lead to the ARM’s success. Starting in July, a six-month research period will begin that addresses the issues of the mission. During this time the technologies, mechanics and resources needed for the mission will be perfected.

As of now, only nine asteroids have been identified that meet the criteria for possible mission nominees. Using NASA’s Spitzer Space Telescope, the most recent asteroid candidate has been identified. The telescope’s “warm” mission began in 2009 once its coolant ran out as planned, and since then Spitzer has been used for more long term and targeted observations. In particular this makes asteroid observation easier as infrared detection is the best way to study less luminous objects.

The recognition of the latest contending asteroid, named 2011 MD, for possible capture as part of the Asteroid Redirect Mission, was published June 19th, 2014 in the Astrophysical Journal Letters. Lead author of the study, Michael Mommert of Northern Arizona University says, “From its perch up in space, Spitzer can use its heat-sensitive infrared vision to spy asteroids and get better estimates of their sizes.” To be deemed valid, the asteroid must be both the right size and mass, but also the rotation rate must be considered to make its capture feasible.

2011 MD is one of the lucky asteroids that has met all necessary criteria for redirection. It has a diameter of about three to six meters (10-20 feet) with a density similar to water, this suggests that the asteroid is mostly empty space, as solid rock is usually at least three times denser than water. 2011 MD may either be a singular solid rock with a halo of particles surrounding it or a collection of smaller space rocks held in tandem by gravity. Only further observation will conclude indefinitely what its composition is.

The idea of capturing an asteroid and setting it in orbit around the moon is truly exciting! It will be the first time that humans have achieved such a massive cosmic endeavor. Building a stellar environment that fits our research needs almost seems more science fiction that reality; however, if we wish to take humans into deep space it is a necessary leap to make. Not only is the Asteroid Redirect Mission awesome in its concept, it will prove to be incredibly valuable in a scientific standpoint as well. John Grunsfeld, associate administrator for NASA’s Science Mission Directorate, says, “Observing these elusive remnants that may date from the formation of our solar system as they come close to Earth, is expanding our understanding of our world and the space it resides in.”

Sources:

NASA, Spitzer Spies an Odd, Tiny Asteroid

NASA, NASA Announces Latest Progress, Upcoming Milestones in Hunt for Asteroids

This article was originally written for and published by From Quarks to Quasars.

Giving Birth to the Serpent’s Stars

Serpens Nebula in infrared. Some of the youngest stars in the Milky Way are seen in yellow and red, in this recent image taken by NASA’s Spitzer Space Telescope. Image credit: NASA/JPL-Caltech/2MASS

Serpens Nebula in infrared. Some of the youngest stars in the Milky Way are seen in yellow and red, in this recent image taken by NASA’s Spitzer Space Telescope. Image credit: NASA/JPL-Caltech/2MASS

Revealed in this recent image taken by NASA’s Spitzer Space Telescope and the Two Micron All Sky Survey (2MASS) is the star-forming region called the Serpens Cloud Core. The cluster shown contains stars that are among the youngest found in our galaxy! Using infrared technology the telescopes captured details from within the stellar breeding ground that were previously unavailable.

By assigning visible colors to the infrared light within the structure, astronomers are able to peer through the fog of gas and dust to observe emerging stars taking shape. “They appear as red, orange and yellow points clustered near the center of the image. Other red features include jets of material ejected from these young stars” (NASA). The nebula’s central cloud, which is chock-full of star birthing ingredients, is colored blue.

Located 750 light-years away in the Serpens (Serpent’s) constellation, this region of space is lacking the existence of super luminous stars. “The core contains a dense, very young, low mass stellar cluster with more than 300 objects in all evolutionary phases, from collapsing gaseous condensations to pre-main sequence stars” (The Serpens Molecular Cloud). Stars, located in the foreground and background of the Serpent, provide most of the pinpricks of light seen in the picture. The formation itself consists of low to moderately sized stars, which appear dimmer in the night sky.

It took an over 16 hours of observation and a compilation of 82 individual photographs to construct the image above. Although the use of light filters makes it possible to examine portions of space that would normally be invisible to us, there is still a region within the Serpens Cloud Core, located to the left, which is too thick for even the infrared filter to penetrate.

By continuing to study such stellar nurseries in detail, scientists can begin to unravel the mystery of how stars with varying masses form within nebulae. It also allows us to understand in, further detail, how chemical composition contributes to the fusion process of star’s lifetime. The evolutionary actions that occur with nebulae contain a wealth of information that can then be applied to future examinations of the cosmos.

 

Written for From Quarks to Quasars, June 12, 2014. For more science news articles check them out!

NASA’s New Technology Captures First High Resolution Images of Coronal Mass Ejection

NASA’s Interface Region Imaging Spectrograph (IRIS) has taken its first images of a huge coronal mass ejection (CME). The spacecraft was launched with the hopes of studying the Sun in exquisite detail. The new technology, which was launched a year ago in June 2013, has the ability to gaze deeper into the atmosphere of the Sun, then ever before.

In images captured on May 9th 2014, scientists were able view a CME that blasted out of a Sun at 1.5 million miles per hour. NASA has compiled a video of the amazing footage. “The field of view [seen in this video] is about five Earths wide and about seven-and-a-half Earths tall” (NASA).

The original version of the video can be found here and is courtesy of NASA.

Though they are similar, coronal mass ejections occur in different atmospheric altitudes than solar flares. They are the result of magnetic fields being violently twisted within the Sun’s outermost atmosphere, the corona. During such ejections an immense amount of plasma, upwards of a billion tons, can be thrown out into the solar system.

It is interesting to note that it may take one to four days before the CME reaches us, and extremely energized particles being pushed by the shock front can reach Earth within an hour. As Earth’s magnetic field attempts to shield us from the harmful radiation, the opportunity to view aurorae arises.

The exact mechanisms of CMEs are not yet known, and since these surges are responsible for a great deal of our solar system’s weather, it is an important piece of information to pin down.

The Interface Region Imaging Spectrograph is a Small Explorer Mission launched by NASA to improve our knowledge of solar material. It has the ability to measure in high-resolution, the temperature, velocity, and energy of substances moving through the inner layers of the Sun’s atmosphere.

A number of NASA affiliates work with the Lockheed Martin Solar & Astrophysics Laboratory on IRIS technology. They are committed to continually pushing the boundary of what we know about the Sun and its ferocious outbursts.

 

Additional sources:

Windows To The UniverseCoronal Mass Ejections.

Encyclopaedia Britannica

NASAIRIS Mission Overview


This article was originally published for From Quarks to Quasars. I highly recommend you check out their website if you not yet familiar with them!


 

Verifying the Expected: Saturn’s Dancing Aurorae

A view of Saturn's aurora (Credit: NASA/JPL/University of Arizona/University of Leicester)

A view of Saturn’s aurora (Credit: NASA/JPL/University of Arizona/University of Leicester)

Just as anticipated, scientists have confirmed that Saturn’s elaborate aurora displays are caused by the fluctuations of its magnetosphere. The findings are not necessarily surprising; in fact, they reiterate what was already expected to be the case. Nonetheless, a recent collaboration between the Hubble Telescope and the Cassini–Huygens spacecraft has increased our knowledge of planetary light shows.

 

PROTECTIVE SHIELDS

Saturn’s core produces a magnetosphere that helps protect it from the Sun’s assailing high-energy particles. Fortunately, this field stops its atmosphere from being blown away by solar winds; perhaps even more fortunate for us, it also allows for the spectacular sight of aurorae!

A labeled diagram of a magnetosphere (Credit: ESA)

A labeled diagram of a magnetosphere (Credit: ESA)

The Earth and Saturn are both planets that produce magnetic field lines; collectively, these lines are called a magnetosphere. Think of it as a bubble surrounding the planet; though instead of it being spherical, the bubble is compressed on the side closest to the sun and an elongated tail is produced at the opposite end, this is called the magnetotail. The Sun’s wind is comprised of plasma- ionized particles that are affected by magnetism. Large amounts of solar energy cause the field lines to stretch and twist; like pulling on one end of a rubber band, eventually the magnetotail becomes so extended that it must snap back and reconnect to the planet. This causes the solar energy trapped within the field lines to discharge into the atmosphere at the poles. On Earth, we see the majority of aurorae as green, but this doesn’t mean that solar energy itself is green in any way. In fact, what it means is that energized particles (electrons and protons) are colliding with gases in the atmosphere and this interaction produces the release of light. It is the atmospheric gases involved that determine which colors are visible; we mostly see green aurorae on Earth because oxygen atoms are being excited.

 

SATURN’S LIGHT SHOWS

But what about Saturn? What colors are produced by its aurorae? By examining the planet in April and May of 2013, scientists were able to capture the twirling images of the light from all angles of the planet, and indeed, they were impressive! Saturn’s intense winds helped amplify the effect; clocking in at an impressive 1,120 mph. Some would even travel three times faster than the rotation of planet.

Several images of an aurora on Saturn’s north pole taken in April and May 2013 by the Hubble Space Telescope. Credit: NASA/ESA, Acknowledgement: J. Nichols (University of Leicester)

Several new images of an aurora brewing on Saturn’s north pole (these were taken by Hubblein April and May 2013) (Credit: NASA/ESA, Acknowledgement: J. Nichols (University of Leicester)

Cassini, which has been orbiting Saturn since 2004, took photographs of the aurorae, but because the atmosphere is primarily made of hydrogen and helium, the light emitted is bluish-red and violet. Perhaps most alluring are the images taken by Hubble using its “Advanced Camera for Surveys.” This instrument allow us to see what is normally not visible to the human eye, a majestic display of ultraviolet light. These findings have recently been accepted for publication in the Geophysical Research Letters.

 

References:

 

This article was written by me, Cassidi Schambre and originally published by From Quarks To Quasars
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Supercooled Water and Bacteria’s Bag of Tricks

Ice crystals have the potential to rupture cells, killing plants. Image source

Ice crystals have the potential to rupture cells, killing plants. Image source

It may seem intuitive to think water freezes at 0°C (32°F) and boils at 100°C (212°F), but unfortunately you’d be wrong. Supercooling is when water can be lowered well past its freezing point without it turning to a solid. Normally water is liquid at room temperature. This means that water molecules are passing freely through each other. Once water turns to solid ice the molecules can no longer move past one another. They are not completely still mind you, they still vibrate; however, the molecule is held in place and cannot escape.

Phase transition refers to changing from one form of matter into another (liquid, solid, gas). These changes are dependent on both temperature and pressure. Here on Earth, we are accustomed to the weight of 14.7 pounds of pressure per square inch (at sea level). Trillions of air molecules in our atmosphere provide this weight, and this affects the phase transitions of substances. By now you may be curious, if water can be supercooled then what else is needed to freeze it other than adequate temperature and pressure? The answer might shock you, it has to do with nucleation and that is where bacteria come into play!

 FREEZING WATER IS HARDER THAN YOU MIGHT THINK

Water generally won’t freeze without the aid of microscopic particles. A nuclei, nucleator, or seed, (all different ways of saying the same thing) is needed to jump start the transition of water into ice. If the sample is pure, meaning free of all particles except the water molecules themselves, it may exist as a liquid much lower than freezing. Theoretically, water can get to -55°C before solidifying, and astonishingly, scientists have discovered liquid water in clouds at -40°C (The Naked Scientists, Cambridge University).

The term heterogeneous ice nucleation is just a fancy way of saying that an impurity is used to start the seeding of ice crystals. As you may know, a lot of stuff is floating around in the atmosphere; pollen, dust, soot, aerosols, algae, sand, and spores are just to name a few, these can all be used as nuclei to freeze water. In general terms, the water molecules form a cage around these particles. This allows the substance to take the approximate shape of an ice crystal. That crystal is now the platform needed to form more crystals, changing the sample from a liquid to a solid as it freezes. It is exciting to realize that every snowflake caught on your tongue contains a seed.

 BACTERIA’S BAG OF TRICKS

Now we can get to those ever so evolutionarily clever microbes. Not every microscopic particle will nucleate water at the same rate. We can thank bacteria for their most amazing ability to freeze water at relatively high temperatures (-8°C to -2°C). Some of the most affective ice nucleators are found in the types of bacteria: Erwinia, Pseudomonas and Xanthomonas (Nature). But why would these bacteria be so efficient at freezing water?

It is thought that bacteria use this skill for mobility. If they’re able to freeze the water around them, for instance while in a cloud, they can then be carried back to Earth in the search for food as hale or snowflakes. These unique plant pathogenic microbes can now use their talented freezing ability for a second time. Once the microbe lands on a leaf it uses a special protein on its outer membrane to mimic the shape of ice crystals.

Pseudomonas syringae shown using SEM. Source: Gordon Vrdoljak, Electron Microscopy Laboratory, U.C. Berkeley

Pseudomonas syringae shown using SEM. Source: Gordon Vrdoljak, Electron Microscopy Laboratory, U.C. Berkeley

Once ice is introduced into a plant cell the membrane bursts. It is the same way for water that gets into cracks in the road, once frozen the concrete ruptures. Now that the bacterium has cracked the shell it can feast on the rich intercellular nutrients.

One of the most amazing things to consider is that scientists estimate 40% of the nuclei floating in the atmosphere are organic in composition. It was also found that cross sections of hale could contain a thousand viable bacteria per milliliter. Without organic material and other microscopic particles, ice would be harder to come by. The ability for water to be supercooled is a fascinating aspect of chemistry. And bacterial nucleators have real world applications in food science, medicine and possible weather modification. So the next time you fill your glass with ice think about the creatures contained within that made that ice possible!