News from Space: Rosetta Maps Comet Surface

Rosetta_and_Philae_at_cometLast month, the European Space Agency Rosetta’s space probe arrived at the comet known as 67P/Churyumov–Gerasimenko, thus becoming the first spacecraft to ever rendezvous with a comet. As it continues on its way to the Inner Solar System, Rosetta’s sensing instruments have been studying the surface in detail in advance of the attempted landing of it’s Philae probe.

Because of this, Rosetta has been able to render a map of the various areas on the surface of the comet, showing that it is composed of several different regions created by a range of forces acting upon the object. Images of the comet’s surface were captured by OSIRIS, the scientific imaging system aboard the Rosetta spacecraft, and scientists analyzing them have divided the comet into several distinct regions, each characterized by different classes of features.

rosettamap-1All told, areas containing cliffs, trenches, impact craters, rocks, boulders and parallel grooves have been identified and mapped by the probe. Some of the areas that have been mapped appear to be caused by aspects of the activity occurring in and around the nucleus of the comet, such as where particles from below the surface are carried up by escaping gas and vapor and strewn around the surface in the surrounding area.

So detailed are these images that many have been captured at a resolution of one pixel being equal to an area of 194 square centimeters (30 square inches) on the comet surface. Dr. Holger Sierks, OSIRIS’ Principal Investigator from the Max Planck Institute for Solar System Science, puts it into perspective:

Never before have we seen a cometary surface in such detail. It is a historic moment – we have an unprecedented resolution to map a comet… This first map is, of course, only the beginning of our work. At this point, nobody truly understands how the surface variations we are currently witnessing came to be.

Rosetta_and_Philae_at_comet_node_full_imageThe newly-generated comet maps and images captured by the instruments on Rosetta will now provide a range of detail on which to finalize possible landing sites for the Philae probe to be launched to the surface . As such, the Rosetta team will meet in Toulouse, France, on September 13 and 14 to allocate primary and backup landing sites (from a list of sites previously selected) with much greater confidence.

At the same time, Rosetta has revealed quite a bit about the outward appearance of the comet, and it aint pretty! More often than not, comets are described as “dirty snowballs” to describe their peculiar composition of ice and dust. But Rosetta’s Alice instrument, which was installed by NASA, has sent back preliminary scientific data that shows that the comet is more akin to a lump of coal.

Rosetta_Artist_Impression_Far_625x469Alice is one of eleven instruments carried aboard Rosetta and one of three instrument packages supplied by NASA for the unmanned orbiter. Essentially, it’s a miniature UV imaging spectrograph that looks for thermal markers in the far ultraviolet part of the spectrum in order to learn more about the comet’s composition and history. It does this by looking specifically for the markers associated with noble gases, such as helium, neon, argon, and krypton.

The upshot of all this high-tech imaging is the surprising discovery of what 67P/Churyumov-Gerasimenko looks like. According to NASA, the comet is darker than charcoal. And though Alice has detected oxygen and hydrogen in the comet’s coma, the patches of barren ice that NASA scientists had expected aren’t there. Apparently, this is because 67P/Churyumov-Gerasimenko is too far away from the warmth of the sun to turn the ice into water vapor.

rosetta-1Alan Stern, Alice principal investigator at the Southwest Research Institute in Boulder, Colorado, had this to say about the revelation:

We’re a bit surprised at just how unreflective the comet’s surface is and how little evidence of exposed water-ice it shows.

Launched in 2004, Rosetta reached 67P/Churyumov-Gerasimenko by a circuitous route involving three flybys of Earth, one of Mars, and a long detour out beyond Jupiter as it built up enough speed to catch up to the comet. Over the coming months, as the Rosetta spacecraft and comet 67P move further into the solar system and approach the sun, the OSIRIS team and other instruments on the payload will continue to observe the comet’s surface for any changes.

alice-first-findings-3Hence why this mission is of such historic importance. Not only does it involve a spacecraft getting closer to a comet than at time in our history, it also presents a chance to examine what happens to a comet as it approaches our sun. And if indeed it does begin to melt and breakdown, we will get a chance to peer inside, which will be nothing less than a chance to look back in time, to a point when our Solar System was still forming.

Sources: gizmag, (2), jpl.nasa.gov, nasa.gov

News from Space: Coming Comet Flyby of Mars

Mars_comet_flybyEarth’s neighbor is once again making the news, but not for the usual reasons. Rather than groundbreaking discoveries or updates being provided by the small army of rovers or satellites, the NASA has now got its eyes firmly fixed on the Red Planet because of an incoming comet. And in the coming months, NASA is taking every precaution to make sure its orbiting spacecraft are out of the way.

Known as C/2013 A1 Siding Spring, the comet’s icy nucleus is predicted to flyby Mars on Oct. 19th, and will miss the planet by just 132,000 km (82,000 miles). That’s 17 times closer than the closest recorded Earth-approaching comet, Lexell’s Comet, which skittered by our world in 1770. And while this is certainly a record-breaking event, no one is concerned about it damaging anything on the Martian surface.

Mars_comet_sidingspringIn fact, it the dust particles embedded in the comet’s vaporizing ice that concerns NASA planners. As dust spreads into a broad tail that could potentially brush Mars’ upper atmosphere, it could also play havoc with or even strike an orbiter. While tiny particles are hardly a hazard on their own, when they are traveling at 56 km (35 miles) per second relative to a spacecraft, a single impact could spell disaster.

Rich Zurek, chief scientist for the Mars Exploration Program at NASA’s Jet Propulsion Laboratory in Pasadena, California, explains:

Three expert teams have modeled this comet for NASA and provided forecasts for its flyby of Mars. The hazard is not an impact of the comet nucleus, but the trail of debris coming from it. Using constraints provided by Earth-based observations, the modeling results indicate that the hazard is not as great as first anticipated. Mars will be right at the edge of the debris cloud, so it might encounter some of the particles — or it might not.

mars-comet-NASAHence why NASA is looking to get its hardware out of the way. The agency currently operates the Mars Reconnaissance Orbiter (MRO) and Mars Odyssey spacecraft with a third orbiter, MAVEN, currently on its way to the planet and expected to settle into orbit a month before the comet flyby. Teams operating the orbiters plan to have all spacecraft positioned on the opposite side of Mars when the comet is most likely to pass by.

Already, mission planners tweaked MRO’s orbit on July 2 to move it toward a safe position with a second maneuver to follow on August 27. A similar adjustment is planned for Mars Odyssey on August 5 and October 9 for the Mars Atmosphere and Volatile Evolution (MAVEN) probe. The time of greatest risk to the spacecraft is brief – about 20 minutes – when the widest part of the comet’s tail passes closest to the planet.

MARS-COMET-surfaceAs for the rovers on the surface, there really isn’t much to worry about there. Similar to what happens with meteor showers here on Earth, Mars’ atmosphere is thick enough that cometary dust particles will incinerate before they reach the surface. And its expected that rover cameras may be used to photograph the comet before the flyby and to capture meteors during the comet’s closest approach.

Despite concerns about dust, NASA knows a good opportunity when it sees one. In the days before and after the flyby, all three orbiters will conduct studies on the comet. According to a recent NASA press release, instruments on MRO and Odyssey will examine the nucleus, coma and tail and possible effects on the Martian atmosphere:

Odyssey will study thermal and spectral properties of the comet’s coma and tail. MRO will monitor Mars’ atmosphere for possible temperature increases and cloud formation, as well as changes in electron density at high altitudes and MAVEN will study gases coming off the comet’s nucleus as it’s warmed by the sun. The team anticipates this event will yield detailed views of the comet’s nucleus and potentially reveal its rotation rate and surface features.

This is Comet Siding Spring’s first trip to the inner solar system, so we can expect plenty of news and updates as it passes Mars. And the icy vapor and dust it leaves behind, which has been in a state of deep freeze since the time the planets were formed, will make for some pretty interest research as well! And be sure to check out this Solar System Scope simulation of the comet’s path as it makes it way through our Solar System past Mars.

Source: universetoday.com, solarsystemscope.com

News From Space: Rosetta Starts, Orion in the Wings

 Quick Note: This is my 1700th post!
Yaaaaaay, happy dance!

Rosetta_Artist_Impression_Far_625x469Space exploration is a booming industry these days. Between NASA, the ESA, Roscosmos, the CSA, and the federal space agencies of India and China, there’s just no shortage of exciting missions aimed at improving our understanding of our Solar System or the universe at large. In recent months, two such missions have been making the news; one of which (led by the ESA) is now underway, while the other (belonging to NASA) is fast-approaching.

In the first instance, we have the ESA’s Rosetta spacecraft, which is currently on its way to rendezvous with the comet 67P/Churyumov-Gerasimenko at the edge of our Solar System. After awaking from a 957 day hibernation back in January, it has just conducted its first instruments observations. Included in these instruments are three NASA science packages, all of which have started sending science data back to Earth.

Rosetta_and_Philae_at_cometSince leaving Earth in March 2004, the Rosetta spacecraft has traveled more than 6 billion km (3.7 billion miles) in an attempt to be the first spacecraft to successfully rendezvous with a comet. It is presently nearing the main asteroid belt between Jupiter and Mars – some 500,000 km (300,000 miles) from its destination. And until August, it will executing a series of 10 orbit correction maneuvers to line it self up to meet with 67P, which will take place on August 6th.

Rosetta will then continue to follow the comet around the Sun as it moves back out toward the orbit of Jupiter. By November of 2014, Rosetta’s mission will then to launch its Philae space probe to the comet, which will provide the first analysis of a comet’s composition by drilling directly into the surface. This will provide scientists with the first-ever interior view of a comet, and provide them with a window in what the early Solar System looked like.

rosetta-1The three NASA instruments include the MIRO, Alice, and IES. The MIRO (or Microwave Instrument for Rosetta Orbiter) comes in two parts – the microwave section and the spectrometer. The first is designed to measure the comet’s surface temperatures to provide information on the mechanisms that cause gas and dust to pull away from it and form the coma and tail. The other part, a spectrometer, will measure the gaseous coma for water, carbon monoxide, ammonia, and methanol.

Alice (not an acronym, just a nickname) is a UV spectrometer designed to determine the gases present in the comet and gauge its history. It will also be used to measure the rate at which the comet releases water, CO and CO2, which will provide details of the composition of the comet’s nucleus. IES (or Ion and Electron Sensor) is one of five plasma analyzing instruments that make up the Rosetta Plasma Consortium (RPC) suite. This instrument will measure the charged particles as the comet draws nearer to the sun and the solar wind increases.

oriontestflightNamed in honor of the Rosetta Stone – the a basalt slab that helped linguists crack ancient Egyptian – Rosetta is expected to provide the most detailed information about what comets look like up close (as well as inside and out). Similarly, the lander, Philae, is named after the island in the Nile where the stone was discovered. Together, they will help scientists shed light on the early history of our Solar System by examining one of its oldest inhabitants.

Next up, there’s the next-generation Orion spacecraft, which NASA plans to use to send astronauts to Mars (and beyond) in the not too distant future. And with its launch date (Dec. 4th, 2014) approaching fast, NASA scientists have set out what they hope to learn from its maiden launch. The test flight, dubbed EFT-1 is the first of three proving missions set to trial many of the in-flight systems essential to the success of any manned mission to Mars, or the outer Solar System.

orionheatshield-1EFT-1 will take the form of an unmanned test flight, with the Orion spacecraft being controlled entirely by a flight control team from NASA’s Kennedy Space Center located in Florida. One vital component to be tested is the Launch Abort System (LAS), which in essence is a fail-safe required to protect astronauts should anything go wrong during the initial launch phase. Designed to encapsulate the crew module in the event of a failure on the launch pad, the LAS thrusters will fire and carry the Orion away from danger.

Orion’s computer systems – which are 400 times faster than those used aboard the space shuttle and have the ability to process 480 million instructions per second- will also be tested throughout the test flight. However, they must also demonstrate the ability to survive the radiation and extreme cold of deep space followed by the fiery conditions of re-entry, specifically in the context of prolonged human exposure to this dangerous form of energy.

oriontestflight-1Whilst all systems aboard Orion will be put through extreme conditions during EFT-1, none are tested as stringently as those required for re-entry. The entire proving mission is designed around duplicating the kind of pressures that a potential manned mission to Mars will have to endure on its return to Earth, and so naturally the results of the performance of these systems will be the most eagerly anticipated by NASA scientists waiting impatiently in the Kennedy Space Center.

Hence the Orion’s heat shield, a new design comprised of a 41mm (1.6-inch) thick slab of Avcoat ablator, the same material that protected the crew of Apollo-era missions. As re-entry is expected to exceed speeds of 32,187 km/h (20,000 mph), this shield must protect the crew from temperatures of around 2,204 ºC (4,000 ºF). Upon contact with the atmosphere, the heat shield is designed to slowly degrade, drawing the intense heat of re-entry away from the crew module in the process.

orionheatshield-2The final aspect of EFT-1 will be the observation of the parachute deployment system. Assuming the LAS has successfully jettisoned from the crew module following launch, the majority of Orion’s stopping power will be provided by the deploying of two drogue parachutes, followed shortly thereafter by three enormous primary parachutes, with the combined effect of slowing the spacecraft to 1/1000th of its initial re-entry speed.

Previous testing of the parachute deployment system has proven that the Orion spacecraft could safely land under only one parachute. However, these tests could not simulate the extremes that the system will have to endure during EFT-1 prior to deployment. The Orion spacecraft, once recovered from the Pacific Ocean, is set to be used for further testing of the ascent abort system in 2018. Data collected from EFT-1 will be invaluable in informing future testing, moving towards a crewed Orion mission some time in 2021.

oriontestflight-2NASA staff on the ground will be nervously monitoring several key aspects of the proving mission, with the help of 1,200 additional sensors geared towards detecting vibration and temperature stress, while taking detailed measurements of event timing. Furthermore, cameras are set to be mounted aboard Orion to capture the action at key separation points, as well as views out of the windows of the capsule, and a live shot of the parachutes as they deploy (hopefully).

The launch promises to be a historic occasion, representing a significant milestone on mankind’s journey to Mars. Orion, the product of more than 50 years of experience, will be the first human-rated spacecraft to be constructed in over 30 years. The Orion will be launch is expected to last four hours and 25 minute, during which time a Delta-2 Heavy rocket will bring it to an altitude of 5,794 km (3,600 miles) with the objective of creating intense re-entry pressures caused by a return from a deep space mission.

And be sure to check out this animation of the Orion Exploration Flight Test-1:

Sources: gizmag.com, (2)

BIG News From Space: Alien Matter Found?

Alien OrganismsIts been an exciting 48 hours for the scientific community. It began when a team of British scientists floated a balloon up into the stratosphere, more than 25 km (16 miles) up, and when it came down they found it was carrying tiny organisms. The scientists claimed that there is no way that such organisms could have come from Earth and found their way into the stratosphere, so they must have come from space.

Specifically, they must have come from a comet, given their particular characteristics, and they could even be evidence that all life on Earth really did originate in the stars. This theory is known as Exogenesis (or Panspermia), and contends that this is how organisms are spread throughout the universe – spawning in certain environments, but flourishing on worlds where they are deposited and conditions are just right.

Alien Organisms1According to Professor Milton Wainwright of the Department of Molecular Biology and Biotechnology at the University of Sheffield, they are “about 95 percent convinced” of that fact, though he admits that it’s hard to be absolutely certainty. But apart from the height of the organisms, which would make it hard to imagine them being from Earth, Wainwright and his team also noted that they bear no physical signs of ever being earthbound.

As Wainwright said in the course of announcing the team’s findings:

There is no known mechanism by which these life forms can achieve that height. As far as we can tell from known physics, they must be incoming. The particles are very clean. They don’t have any dust attached to them, which again suggests they’re not coming to earth. Similarly, cosmic dust isn’t stuck to them, so we think they came from an aquatic environment, and the most obvious aquatic environment in space is a comet.

In addition, the science team ruled out the possibility that the particles were originally from Earth and were blasted into the stratosphere by a volcano, noting that it’s been too long since the last volcanic eruption on Earth for the particles to have maintained such a height. So the tentative conclusion remains, that the organisms were placed in orbit by a passing comet.

DNA-1What’s even more exciting is the prospect that the organisms, though they are all likely dead at this point, are likely to contain alien DNA. If this proves to be true, it could further the idea that life on Earth may have had its beginnings in cosmos. Next month, the team plans to try the balloon test again to see if they can both confirm their results and find new organisms in upcoming meteor shower tied to Halley’s Comet.

Exciting prospects indeed. But almost immediately after the announcement been made, dissenting voices began to come forward to poke holes in the team’s theory. One such person is Phil Plait, an astronomer who upon reading the findings in the Journal of Cosmology, raised a number of concerns and criticisms about the team’s research.

First, Plait notes, one member of the research team, Chandra Wickramasinghe, has claimed numerous times that he’s discovered diatoms – a type of phytoplankton found in meteorites – and this particular paper also includes similar diatom findings. Wickramsinghe also, according to Plait, has a long history of making dubious claims about extraterrestrial life, using less-than-thorough research.

PanspermiaPlait also noted that the Journal of Cosmology, where the paper was published, has a less-than-spotless reputation. In the past, the quality of peer review at the journal has been questioned, and they have also been accused of promoting fringe and speculative viewpoints on astrobiology, astrophysics, and quantum physics. Of particular concern is the journal’s apparent bias that the theory of Panspermia is established fact, which remains a theory.

But as to the scientific findings themselves, there’s the question of whether the diatom really came from space or became attached to the balloon as it transited from the surface into orbit. While the team claims that precautions were taken and the sample was too clean, extended testing may prove this conclusion to be wrong, and possibly premature.

Second, Plait disputes the conclusion that the diatom could not have been put up in the atmosphere by a volcanic eruption. Specifically, he noted that the researchers didn’t seem to take into account things like turbulence in the stratosphere that could have kept objects previously hurled up there by volcanoes floating around for quite some time.

panspermia1Then there’s the claim that evidence points that the organisms came from a comet. The fact that it was “remarkably clean and free of soil or other solid material,” works against this conclusion, according to Plait. If indeed it came embedded in rock, there would surely be samples of soil, dust, ice or minerals attached to it, as these are things commonly found in a comet.

And finally, there’s the theory the researchers developed that these organisms are evidence that life actually began somewhere in space, then came to Earth. While Panspermia is a good theory, Plait claims that the scientists are going about arguing it in a way that is not strictly scientific:

Panspermia is worth investigating, but it’s worth investigating correctly. Outrageous claims on thin evidence with huge conclusion-jumping don’t comprise the best way to do it. Stories like this one are sexy and sure bait for an unskeptical media, of course. But at the very least they don’t help the public understand science and the scientific process, and I know some scientists take an even dimmer view of it.

But of course, the announcement was just made and there’s still plenty of checking to do. In the meantime, we can all certainly speculate, and I would like to hear from the people out there. What do you think? Does this discovery constitute a scientific breakthrough, or is it an elaborate hoax or a case of eager scientists jumping to conclusions?

Mars_Earth_Comparison-580x356And let’s not forget, this announcement comes not long after Professor Steven Benner’s similar announcement that new evidence connects the origin of life on Earth to life on Mars. No reason why Exogenesis and the Martian hypothesis can’t coexist now is there?

Sources: blastr.com, (2)

News From Space: We Come From Mars!

Mars_Earth_Comparison-580x356Men are from Mars, women are… also from Mars? That is the controversial theory that was proposed yesterday at the annual Goldschmidt Conference of geochemists being held in Florence, Italy. The proposal was made by Professor Steven Benner of the Westheimer Institute of Science and Technology in Florida and is the result of new evidence uncovered by his research team.

The theory that life on Earth originated on Mars has been argued before, but has remained contentious amongst the scientific community. However, Benner claims that new evidence supports the conclusion that the Red Planet really is our ancestral home by demonstrating that the elements for life here could only form on Mars, and came here via a Martian meteorite.

Asteroid-Impacts-MarsAccording to the theory, rocks violently flung up from the Red Planet’s surface during mammoth collisions with asteroids or comets then traveled millions of kilometers across interplanetary space to Earth. Once they reached Earth’s atmosphere. they melted, heated and exploded violently before the remnants crashed into the solid or liquid surface.

All that would be needed is for a few of those space born rocks to contain microbes from Mars surface. These building blocks of life would have to survive the journey through space and the impact on Earth to make this happen. But research into Exogenesis – the possibility that life was transplanted on Earth by meteorites – has already shown that this is possible.

curiosity_sol-177-1What’s more, NASA’s Curiosity Rover was expressly created to search for the the environmental conditions that would support life. Less than half a year into its mission it accomplished just that, locating proof of the existence of water and a habitable zone. Between it and the Opportunity Rover, the search to determine if life still exists – in the form of organic molecules – continues and is expected to yield results very soon.

But of course, Benner was quick to point out that there is a difference between habitability (i.e. where can life live) and origins (where might life have originated). The presence organic molecules alone is not enough when it comes to the mystery of life’s creation, and when it comes to making the great leap between having the necessarily elements and the existence of living organisms, scientists remain hung up on two paradoxes.

These are known as the tar paradox and the water paradox, respectively. The former paradox addresses how life as we know it comes down to the presence of organic molecules, which are produced by the chemistry of carbon and its compounds. However, the presence of these compounds does not ensure the creation of life, and laboratory experiments to combine and heat them has only ever produced tar.

mars_lifeAs he puts it, the origin of life involves “deserts” and oxidized forms of the elements Boron (B) and Molybdenum (Mo) – namely borate and molybdate. Essentially, these elements are the difference between the formation of tar and RNA, the very building block of life:

Certain elements seem able to control the propensity of organic materials to turn into tar, particularly boron and molybdenum, so we believe that minerals containing both were fundamental to life first starting. Analysis of a Martian meteorite recently showed that there was boron on Mars; we now believe that the oxidized form of molybdenum was there too.

The second paradox relates to water, which is believed to be intrinsic for life to flourish, but can be also hazardous to its formation. According to modern research, RNA forms prebiotically, requiring mineral species like borate to capture organic elements before they devolve into tar and molybdate to arrange the material to give it ribose – organic sugars, also intrinsic to life.

Mars-snow-header-640x353This can only occur in deserts, he claims, because water is detrimental to RNA and inhibits the formation of borates and molybdates. And from a geological standpoint, there was simply too much water covering the early Earth’s surface to allow for this creation process to take place:

[W]ater is corrosive to RNA, which scientists believe was the first genetic molecule to appear. Although there was water on Mars, it covered much smaller areas than on early Earth. Various geologists will not let us have these [borates and molybdates] on early Earth, but they will let us have them on Mars. So IF you believe what the geologists are telling you about the structure of early Earth, AND you think that you need our chemistry to get RNA, AND IF you think that life began with RNA, THEN you place life’s origins on Mars,

All of this has served to throw the previously-held theory – that life came to Earth through water, minerals and organics being transported by comets – into disarray. Based on this new theory, comets are a bad candidate for organic life since they lack the hot, dry conditions for borate and molybdate formation.

Living-Mars.2If the new theory is to be believed, Mars boasted the proper conditions to create the elements for life, while Earth possessed the water to help it flourish. If such a partnership is needed for the creation of organic life, then scientists will need to reevaluate the likelihood of finding it elsewhere in the universe. Between the existence of water and hot dry environments, life would seem to require more specialized conditions than previously though.

But of course, the debate on whether Earthlings are really Martians will continue as scientific research progresses and definitive proof is discovered and accepted by the majority of the scientific community. In the meantime, Curiosity is expected to rendezvous with Mount Sharp sometime next spring or summer, where it will determine if organic molecules and elements like Boron and Molybdenum exist there.

And on Nov. 18th, NASA will launch its next mission to Mars – the MAVEN orbiter – which will begin studying the upper Martian atmosphere for the first time, determining its previous composition, and where all the water went and when was it lost. So we can expect plenty more news to come to us from our neighboring Red Planet. Wait and see!

Source: universetoday.com