Fluffy, with a core of density. That’s what the interior of the asteroid 87 Sylvia likely looks like, astronomers say. The neatest thing about that observation? It didn’t require a drill or even a spacecraft visit. That came from watching the orbits of the asteroid’s two moons, Romulus and Remus.
The discovery illustrates the power of amateur and professional astronomers working together, the team said. On Jan. 6, dozens of small telescopes across France, Greece and Italy were set up to watch a celestial show: watching Sylvia move in front of an eleventh-magnitude star. The professionals received assistance from European Asteroidal Occultations (EURASTER), a group of professional and amateur observers, for this event.
“Observers at different locations see different parts of the asteroid, or its moons, passing in front of the star,” the team stated in a press release. “Such occultations allow exquisitely precise measurements of the relative positions and sizes of the occulting objects.”
Of the 50 observers watching the show, twelve of them saw the occultation, which lasted anywhere from four to 10 seconds depending on where the observers were.
Subsequently, the professional astronomers determined how Sylvia is shaped by using that information and combining it with other data, such as recordings of the asteroid’s light variations that happened as it spun, and some direct images using adaptive optics. The team noted that Romulus and Remus don’t seem to change in their paths in space due to Sylvia’s non-circular shape, making them conclude that it has an interior of different materials.
All told, there were 66 adaptive optics observations of the asteroids using 8 to 10 meter telescopes at the W. M. Keck Observatory, the European Southern Observatory, and Gemini North. Calculations of the system came from the Institute of Celestial Mechanics and Ephemerides Calculations (IMCCE) of the Paris Observatory.
“Four observers detected a two-second eclipse of the star caused by Romulus, the outermost moon, at a relative position close to our prediction. This result confirmed the accuracy of our model and provided a rare opportunity to directly measure the size and shape of the moon,” stated Jérôme Berthier, an IMCCE astronomer.
“Combined observations from small and large telescopes provide a unique opportunity to understand the nature of this complex and enigmatic triple asteroid system,” added Francis Marchis, a senior research scientist at the Carl Sagan Center of the SETI Institute, who led the research. “Thanks to the presence of these moons, we can constrain the density and interior of an asteroid, without the need for a spacecraft’s visit. Knowledge of the internal structure of asteroids is key to understanding how the planets of our solar system formed.”
The results were presented yesterday (Oct. 7) at the American Astronomical Society’s division of planetary sciences meeting in Denver.
Can’t find asteroid 2010 QW1 in the Minor Planet Database? No, the “Men in Black” didn’t secretly remove this Earth-orbiting asteroid from the listing… but recent top-notch detective work by astronomers did.
The mystery of this object all started back on August 23rd of this year, when the PanSTARRS sky survey based on the summit of Haleakala on the island of Maui in Hawai’i spotted an asteroid that was given the provisional designation of 2013 QW1.
The object was in a wide-ranging orbit around the Earth, leading astronomers to wonder if it was a naturally captured asteroid or perhaps space debris from a previous launch. Either solution to the dilemma would be fascinating. Our large Moon keeps the Earth pretty well swept clear of debris, though a “second Moon,” however small, would be an interesting find. And if 2013 QW1 were to prove artificial, it just might be a piece of history.
The European Space Agency’s NEO Coordination Centre decided to take up the challenge. A call went out to track and observe the 2013 QW1, and a team led by Elisabetta Dotto of INAF-Observatorio di Roma & Maria Barucci & Davide Perna of the Observatoire de Paris managed to get time on the Italian Telescopio Nazaionale Galileo based at La Palma to obtain a spectrum of the object.
“It was a bit of a challenge, because the object was moving fast with respect to a typical NEO,” said Dr. Perna in a recent ESA press release.
The team used an instrument known as DOLORES to make the crucial measurements. DOLORES stands for the Device Optimized for LOw RESolution. The spectrum obtained in the early morning hours of August 25th shows something much brighter than your typical asteroid, but is characteristic of a painted metallic object.
And thus, 2013 QW1 was removed from the ledger of NEO asteroids maintained by the IAU Minor Planet Center (MPEC). And the leading suspect? The third stage booster of a Chinese Long March 3C rocket that launched the Chang’e 2 spacecraft from Xichang, China on October 1st, 2010.
Chang’e-2 entered lunar orbit 8 days after launch, and departed on June 8th of the following year after studying and mapping the Moon. Chang’e-2 then went on to become the first spacecraft to directly reach the L2 Lagrange point 1.5 million kilometres beyond Earth from lunar orbit. The spacecraft also made the first flyby of NEO asteroid 4179 Toutatis on December 13th of last year. The probe is estimated to continue functioning into 2014, and will be used to hone China’s ability to track objects in deep space.
The NORAD tracking identification assigned to the 3rd stage booster that launched Chan’ge-2 is 2010-50B.
This sort of discovery is not without precedent.
On September 3rd, 2002, amateur astronomer Bill Yeung discovered an asteroid tentatively designated J002E3. Subsequent studies revealed that the asteroid had a spectrum consistent with that of titanium oxide paint, a decidedly unasteroid-like coating for a space rock to sport. This was, however, a common veneer in use during the Apollo era, and it is now known that J002E3 is the S-IVB third stage booster that launched the second mission to land men on the Moon on November 14th, 1969. Unlike other boosters, such as the one that launched Apollo 14, the Apollo 12 3rd stage did not impact the Moon as part of seismic experiments. After a brief period as a “pseudo-moon” of the Earth, J002E3 was kicked out into solar orbit in June 2003 and may return to our neighborhood once again in the 2040s.
NASA’s Lunar Reconnaissance Orbiter has documented the lunar crash sites of these historic boosters. It’s of note that the Apollo 10 Lunar Module Snoopy remains discarded out in solar orbit as well, having been used as a dress rehearsal for the historic Apollo 11 landing. Apollo 10 never landed on the Moon. Efforts have been made by UK astronomer Nick Howes to recover it as well.
And there are more relics of the Space Age awaiting discovery. One of the first things we always check in the case of a pass by a newly discovered NEO closer than the Moon to the Earth is its history, to see if it matches up with any launches headed out beyond Earth orbit in the past.
And the upcoming Mars launches of MAVEN and India’s Mars Orbiter Mission in October & November will be the first to depart Earth orbit since 2011. These will give future generations of asteroid hunters new human-made space hardware to ponder.
The B612 Foundation’s asteroid-hunting Sentinel Space Telescope will also “up the game,” scouting for asteroids from a vantage point interior to the Earth’s orbit. Sentinel is slated for launch in 2016 atop a SpaceX Falcon 9 rocket.
And no, the fabled “Black Knight” satellite of UFO conspiracy buffs’ dreams is nowhere to be found.
What other fascinating relics of the Space Age lie are out there in the solar system, waiting to tell their tale?
It’s a case of mistaken identity: a near-Earth asteroid with a peculiar orbit turns out not to be an asteroid at all, but a comet… and not some Sun-dried burnt-out briquette either but an actual active comet containing rock and dust as well as CO2 and water ice. The discovery not only realizes the true nature of one particular NEO but could also shed new light on the origins of water here on Earth.
Designated 3552 Don Quixote, the 19-km-wide object is the third largest near-Earth object — mostly rocky asteroids that orbit the Sun in the vicinity of Earth.
According to the IAU, an asteroid is coined a near-Earth object (NEO) when its trajectory brings it within 1.3 AU from the Sun and within 0.3 AU of Earth’s orbit.
About 5 percent of near-Earth asteroids are thought to actually be dead comets. Today an international team including Joshua Emery, assistant professor of earth and planetary sciences at the University of Tennessee, have announced that Don Quixote is neither.
“Don Quixote has always been recognized as an oddball,” said Emery. “Its orbit brings it close to Earth, but also takes it way out past Jupiter. Such a vast orbit is similar to a comet’s, not an asteroid’s, which tend to be more circular — so people thought it was one that had shed all its ice deposits.”
Using the NASA/JPL Spitzer Space Telescope, the team — led by Michael Mommert of Northern Arizona University — reexamined images of Don Quixote from 2009 when it was at perihelion and found it had a coma and a faint tail.
Emery also reexamined images from 2004, when Quixote was at its farthest distance from the Sun, and determined that the surface is composed of silicate dust, which is similar to comet dust. He also determined that Don Quixote did not have a coma or tail at this distance, which is common for comets because they need the sun’s radiation to form the coma and the sun’s charged particles to form the tail.
The researchers also confirmed Don Quixote’s size and the low, comet-like reflectivity of its surface.
“The power of the Spitzer telescope allowed us to spot the coma and tail, which was not possible using optical telescopes on the ground,” said Emery. “We now think this body contains a lot of ice, including carbon dioxide and/or carbon monoxide ice, rather than just being rocky.”
This discovery implies that carbon dioxide and water ice might be present within other near-Earth asteroids and may also have implications for the origins of water on Earth, as comets are thought to be the source of at least some of it.
The amount of water on Don Quixote is estimated to be about 100 billion tons — roughly the same amount in Lake Tahoe.
“Our observations clearly show the presence of a coma and a tail which we identify as molecular line emission from CO2 and thermal emission from dust. Our discovery indicates that more NEOs may harbor volatiles than previously expected.”
– Mommert et al., “Cometary Activity in Near–Earth Asteroid (3552) Don Quixote “
The findings were presented Sept. 10 at the European Planetary Science Congress 2013 in London.
3552 Quixote isn’t the only asteroid found to exhibit comet-like behavior either — check out Elizabeth Howell’s recent article, “Asteroid vs. Comet: What the Heck is 3200 Phaethon?” for a look at another NEA with cometary aspirations.
Sometimes, putting things into categories difficult. Witness how many members of the general public are still unhappy that Pluto was reclassified as a dwarf planet, a decision made by the International Astronomical Union more than seven years ago.
And now we have 3200 Phaethon, an asteroid that is actually behaving like a comet. Scientists found dust that is streaming from this space rock as it gets close to the sun — similarly to how ices melt and form a tail as comets zoom by our closest stellar neighbor.
Phaethon’s orbit puts it in the same originating region as other asteroids (between Mars and Jupiter), but its dust stream is much closer to actions performed by a comet — an object that typically comes from an icy region way beyond Neptune. So far, therefore, the research team is calling Phaethon a “rock comet.” And after first proposing a theory a few years ago, they now have observations as to what may be going on.
Phaethon is not only an asteroid, but also a source of a prominent meteor shower called the Geminids. This shower happens every year around December when the Earth plows into the cloud of debris that Phaethon leaves in its wake. Astronomers have known about the Geminids’ source for a generation, but for decades could not catch the asteroid in the act of shedding its stuff.
That finally came with images of NASA’s twin sun-gazing Solar TErrestrial RElations Observatory (STEREO) spacecraft that were taken between 2009 and 2012. The researchers saw a “comet-like tail” extending from the 3.1-mile (five kilometer) asteroid. “The tail gives incontrovertible evidence that Phaethon ejects dust,” stated David Jewitt, an astronomer at the University of California, Los Angeles who led the research. “That still leaves the question: why?”
The answer lies in just how close Phaethon whizzes past the sun. At perihelion, its closest approach to the sun, it only appears eight degrees (16 solar diameters) away from the sun in Earth’s sky. This close distance makes it all but impossible to study the asteroid without special equipment, which is why STEREO came in so handy.
When Phaethon reaches its closest approach of 0.14 Earth-sun distances, surface temperatures rise above an estimated 1,300 degrees Fahrenheit (700 degrees Celsius). It’ s way too hot for ice, as what happens with a comet. In fact, it’s probably hot enough to make the rocks crack and break apart. The researchers publicly hypothesized this was happening at least as far back as 2010, but this finding provided more evidence to support that theory.
“The team believes that thermal fracture and desiccation fracture (formed like mud cracks in a dry lake bed) may be launching small dust particles that are then picked up by sunlight and pushed into the tail,” a statement from the research team read.
“While this is the first time that thermal disintegration has been found to play an important role in the solar system,” they added, “astronomers have already detected unexpected amounts of hot dust around some nearby stars that might have been similarly produced.”
The results were presented at the European Planetary Science Congress on Tuesday. By the way, STEREO also caught Mercury behaving somewhat like a comet in results released in 2010, although that find was related to the planet’s escaping sodium atmosphere.
Read more about the research in the June 26 issue of Astrophysical Letters. A preprint version is also available on Arxiv.
This week offers a fine chance to catch sight of a unique asteroid.
324 Bamberga reaches opposition this week in the constellation Pisces on (friggatriskaidekaphobics take note) Friday the 13th at 7AM EDT/11:00 Universal Time.
About 230 kilometres in size, 324 Bamberga reaches 0.81 astronomical units from the Earth this week. No other asteroid so large gets so close.
Discovered on February 25th, 1892 by Johann Palisa, 324 Bamberga only reaches a favorable opposition once every 22 years.
Shining at magnitude +8.1, 324 Bamberga is also one of the highest numbered asteroids visible with binoculars. Earth-crossing asteroids 433 Eros, which made a close pass last year, and 4179 Toutatis are two of the very few asteroids that possess a larger number designations that can regularly reach +10th magnitude.
So, why did it take so long for 324 Bamberga to be uncovered? One factor is its high orbital eccentricity of 0.34. This means that most of the oppositions of the asteroid aren’t favorable. 324 Bamberga orbits the Sun once every 4.395 years and only comes around to an opposition that lands near perihelion once every 22 Earth years. Perihelion this year occurs only 45 days after opposition on October 27th.
The resonance between 324 Bamberga and Earth is nearly five Earth orbits for every one circuit of the Sun for the asteroid and is offset by only 9 days, meaning that the 22 year window to see the asteroid will actually become less favorable in centuries to come. 324 Bamberga made its last favorable appearance on September 15th, 1991 and won’t surpass +10th magnitude again until September 2035.
Observing asteroids requires patience and the ability to pick out a slowly moving object amidst the starry background. 324 Bamberga spends September west of the circlet of Pisces, drifting two degrees a week, or just over 17’ a day, to cross over into the constellation Pegasus in early October.
324 Bamberga will be moving too slow to pick up any motion in real time, but you can spy it by either sketching the field on successive nights or photographing the region and noting if the asteroid can be seen changing position against the background of fixed stars. Start hunting for 324 Bamberga tonight, as the Full Harvest Moon will be visiting Pisces later next week on the 19th.
324 Bamberga is also unique as the brightest C-type asteroid that is ever visible from Earth. The runner up in this category is asteroid 10 Hygiea, which can shine a full magnitude fainter at opposition.
It’s also remarkable that Palisa actually managed to discover 324 Bamberga while it was at 12th magnitude! Palisa was one of the most prolific visual hunters of asteroids ever, discovering 121 asteroids from 1874 to 1923. He accomplished this feat first with the use of a 6” refractor while based at the Austrian Naval Observatory in Pola (now the Croatian town of Pula) and later using the Vienna observatory’s 27” inch refractor.
324 Bamberga itself takes its name from the town of Bamberg in Bavaria, the site of the 1896 meeting of the Astronomische Gesellschraft.
An occultation of a star by 324 Bamberga on December 8th, 1987 allowed astronomers to pin down its approximate size. Searches have also been carried out during occultations for any possible moons of this asteroid, though thus far, none have been discovered.
It’s interesting to note that 324 Bamberga will also actually occult the star 2UCAC 3361042 tonight in the early morning hours at 8:59-9:10 UT for observers spanning a path from Florida to Oregon. The magnitude drop will, however, be very slight, as the star is actually 3 full magnitudes fainter than the asteroid itself. Dave Gee caught a fine occultation of a 7.4 magnitude star in the constellation Corvus by 324 Bamberga in 2007.
There’s also something special about this time of year and the region that 324 Bamberga is crossing. More visual discoveries of asteroids have been historically made in the month of September than any other calendar month. In fact, 344 of the first 1,940 numbered asteroids were found in September, more than twice the average. Palisa’s own track record bears this out, though 324 Bamberga was discovered in February.
One of the primary reasons for a September surge in discoveries is viewing direction. Astronomers of yore typically hunted for asteroids approaching opposition in the anti-sunward direction, which in September lies in the relatively star poor fields of Pisces. In December and June —the months with the lowest numbers of visual discoveries at only 75 and 65 for the “first 1,940” respectively —the anti-sunward point lies in the star-rich regions of Sagittarius and Gemini. And by the way, the meteor that exploded over the city of Chelyabinsk on February 15th was sneaking up on the Earth from the sunward direction.
Be sure to catch a glimpse of this unique asteroid through either binoculars or a telescope over the coming weeks. The next chance to observe 324 Bamberga won’t roll around again until September 2035… it’ll be great to compare notes of the 2013 apparition on that far off date!
NASA is really getting into this crowd-sourcing thing. The space agency asked and the public responded with hundreds of ideas of what missions could be done with asteroids in regards to protecting Earth from these space rocks and finding an asteroid humans can explore. NASA received over 400 responses to their “Asteroid Initiative Request For Information” request, hearing from the space industry, universities, and the general public.
Now, after looking at all the responses, NASA has chosen 96 ideas it regards as most promising, ranging from asteroid observation plans to asteroid redirection, deflection or capture systems, to creating crowd sourcing and citizen science opportunities.
Next, NASA will host an Asteroid Initiative Idea Synthesis Workshop where NASA personnel and the space community will discuss and further these 96 ideas to narrow them down even further to help with its planning activities and future missions.
The 96 ideas were chosen by a team of NASA scientists, engineers, and mission planners who evaluated the proposed ideas. The evaluation team rated the responses for relevance to the RFI objectives, innovativeness of the idea, maturity of the development approach, and potential to improve mission affordability.
This is the first time NASA has used this type of crowd-sourcing and discussion method to look at possible future missions.
NASA said the ideas proposed “provide the agency with fresh insight into how best to identify, capture and relocate a near-Earth asteroid for closer study and respond to asteroid threats.” Ideas included pointers on how to decrease an asteroid’s spin, nudge it away from a path toward Earth, take samples to return to Earth and create activities to heighten public awareness of not only the threat asteroids pose, but the valuable resources and scientific benefits they may offer.
“This rich set of innovative ideas gathered from all over the world provides us with a great deal of information to factor into our plans moving forward,” said Robert Lightfoot, Associate Administrator for NASA. “We’re making great progress on formulating this mission, and we look forward to discussing further the responses we received to the RFI.”
The upcoming public workshop will be held on Sept. 30 – Oct. 2 and onsite participation is limited to just the presenters, but it appears the workshop will be webcast (more info later), as NASA said they will release information on virtual participation options as the workshop nears.
It’s easy to take the International Space Station for granted. It’s been planned, under construction and/or operated for decades. Humans have occupied it continuously for 4,684 days (close to 13 years) as of today. According to two space policy experts, however, NASA should already be thinking of what it’s going to do next after the station’s current agreement expires in 2020.
Ignoring the deadline, they said, could lead to consequences such as (in one scenario) the end of U.S. government spaceflight altogether.
Below are edited excerpts from two officials from George Washington University’s Elliott School of International Affairs. Scott Pace is its director, and John M. Logsdon is a professor emeritus. They spoke with reporters Thursday (Aug. 29) about the coming NASA budget decision and their views on the agency’s future.
We’d also like to get your feedback on their ideas, so please leave your thoughts in the comments.
Pace: In my view, the House numbers are complying with the Budget Control Act in terms of sequestration numbers. In the Senate, the numbers were not in line with the Budget Control Act, but reflected what the priorities of the authorization committee were … I would argue, and we’ll see if others agree, that the Senate has marginalized themselves in this discussion. The appropriations staff will have the larger say in that, but on the House side, the authorizors and the appropriators will be together because they have discussed what their priorities were.”
Where NASA’s direction comes from:
Logsdon: It’s a residual of 40 years of failure to reach consensus of what the U.S. should be doing in space and particularly, human spaceflight. In the first year and a half of the Nixon administration, he was faced with what to do after Apollo and basically punted. He said, “Let’s develop means, rather than set goals.” The means was the shuttle … The lack of leadership of this administration, which is not much different than most presidents since Nixon and including Nixon, have put us in a situation that is unfortunate, and, as Scott [Pace] says, leads to a lot of drift and lack of sense of purpose.
Pace: [One goal for NASA often is to implement] priorities of decadal surveys from the National Academy of Sciences. Things like the asteroid redirect mission, which will burden portions of the human and science programs, have no decadal survey mention or no larger contribution to the science. It’s another capability-driven-evolution sort of project, with some very basic flaws to it in terms of not providing that long-term sense of strategic purpose.
Logsdon: There’s not enough money to have a robust space exploration program and to use the space station at a $3 billion a year level in 2028. None of the current partners — with a possible exception of Canada — but certainly, Europe and Japan are not enthusiastic about spending money on space station post-2020. They really had to be dragged, their governments had to be dragged, to commit the funds for the extension to 2020. It’s not clear, if there is a decision to go beyond, whether the United States will have its early partners [committed.]
Pace: What happens with other major scientific facilities that NASA has, like the Hubble Space Telescope, is you have a senior review. After you’ve met the initial requirements [of the mission], you ask what is the facility costing me, what am I getting out of it, and make a decision whether to continue. You will see, in anticipation of 2020, you will see the beginnings of a senior review to see what will be in the NASA 2020 budget. It is dependent upon data being created now — the scientific and technical benefits — and where will the benefits flow for plans beyond space station. If there are no plans for human flight beyond space station … the default option is to do the station as long as it is technically capable, but eventually it will be deorbited. And there will be an end to U.S. government spaceflight.
If government-funded human spaceflight could end in the United States:
Pace: I can imagine a President presiding over the end of human spaceflight, not as a conscious decision but as an unfortunate accident. Drift is the most dangerous thing for NASA.
Logsdon: Would any President be willing to be that person to end the government-sponsored spaceflight program? I’m not sure the answer is no. It could be that a future President could say we’ve done it and there’s no future reasoning to continue at fairly high expense to continue to do it. But I would speculate the more likely answer, given the industrial and regional interests, is some sort of limping through human spaceflight. It’s more similar than different for the past four decades.
What NASA needs right now:
Logsdon: I’m taking less about the NASA leadership than I am the White House and Congressional leadership. What’s missing is a sense of strategic purpose of the organization, what should it be doing, and that is the job of a national leader. It is enunciating for NASA, as well as other government agencies, for what its long-term and even midterm strategic purpose is in terms of the natinoal interest ought to be.
Pace: [The United States must determine] what is the role of international leadership in space for the United States and to what extent are we willing to make plans for beyond the station. 2020 is not that far away. The focus on NASA right now, with ISS, is utilization. The station has been a great diplomatic success, great technical success, but it’s not clear if it will be a great scientific success.
Are Earthlings really Martians ?
Did life arise on Mars first and then journey on rocks to our planet and populate Earth billions of years ago? Earth and Mars are compared in size as they look today. NASA’s upcoming MAVEN Mars orbiter is aimed at answering key questions related to the habitability of Mars, its ancient atmosphere and where did all the water go. Story updated[/caption]
That’s the controversial theory proposed today (Aug. 29) by respected American chemist Professor Steven Benner during a presentation at the annual Goldschmidt Conference of geochemists being held in Florence, Italy. It’s based on new evidence uncovered by his research team and is sure to spark heated debate on the origin of life question.
Benner said the new scientific evidence “supports the long-debated theory that life on Earth may have started on Mars,” in a statement. Universe Today contacted Benner for further details and enlightenment.
“We have chemistry that (at least at the level of hypothesis) makes RNA prebiotically,” Benner told Universe Today. “AND IF you think that life began with RNA, THEN you place life’s origins on Mars.” Benner said he has experimental data as well.
First- How did ancient Mars life, if it ever even existed, reach Earth?
On rocks violently flung up from the Red Planet’s surface during mammoth collisions with asteroids or comets that then traveled millions of miles (kilometers) across interplanetary space to Earth – melting, heating and exploding violently before the remnants crashed into the solid or liquid surface.
“The evidence seems to be building that we are actually all Martians; that life started on Mars and came to Earth on a rock,” says Benner, of The Westheimer Institute of Science and Technology in Florida. That theory is generally known as panspermia.
To date, about 120 Martian meteorites have been discovered on Earth.
And Benner explained that one needs to distinguish between habitability and the origin of life.
“The distinction is being made between habitability (where can life live) and origins (where might life have originated).”
NASA’s new Curiosity Mars rover was expressly dispatched to search for environmental conditions favorable to life and has already discovered a habitable zone on the Red Planet’s surface rocks barely half a year after touchdown inside Gale Crater.
Furthermore, NASA’s next Mars orbiter- named MAVEN – launches later this year and seeks to determine when Mars lost its atmosphere and water- key questions in the Origin of Life debate.
Of course the proposed chemistry leading to life is exceedingly complex and life has never been created from non-life in the lab.
The key new points here are that Benner believes the origin of life involves “deserts” and oxidized forms of the elements Boron (B) and Molybdenum (Mo), namely “borate and molybdate,” Benner told me.
“Life originated some 4 billion years ago ± 0.5 billon,” Benner stated.
He says that there are two paradoxes which make it difficult for scientists to understand how life could have started on Earth – involving organic tars and water.
Life as we know it is based on organic molecules, the chemistry of carbon and its compounds.
But just discovering the presence of organic compounds is not the equivalent of finding life. Nor is it sufficient for the creation of life.
And simply mixing organic compounds aimlessly in the lab and heating them leads to globs of useless tars, as every organic chemist and lab student knows.
Benner dubs that the ‘tar paradox’.
Although Curiosity has not yet discovered organic molecules on Mars, she is now speeding towards a towering 3 mile (5 km) high Martian mountain known as Mount Sharp.
Upon arrival sometime next spring or summer, scientists will target the state of the art robot to investigate the lower sedimentary layers of Mount Sharp in search of clues to habitability and preserved organics that could shed light on the origin of life question and the presence of borates and molybdates.
It’s clear that many different catalysts were required for the origin of life. How much and their identity is a big part of Benner’s research focus.
“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,” says Benner in a statement. “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. He says that there was too much water covering the early Earth’s surface, thereby causing a struggle for life to survive. Not exactly the conventional wisdom.
“Not only would this have prevented sufficient concentrations of boron forming – it’s currently only found in very dry places like Death Valley – but water 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.”
I asked Benner to add some context on the beneficial effects of deserts and oxidized boron and molybdenum.
“We have chemistry that (at least at the level of hypothesis) makes RNA prebiotically,” Benner explained to Universe Today.
“We require mineral species like borate (to capture organic species before they devolve to tar), molybdate (to arrange that material to give ribose), and deserts (to dry things out, to avoid the water problem).”
“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,” Benner elaborated.
“The assembly of RNA building blocks is thermodynamically disfavored in water. We want a desert to get rid of the water intermittently.”
I asked Benner whether his lab has run experiments in support of his hypothesis and how much borate and molybdate are required.
“Yes, we have run many lab experiments. The borate is stoichiometric [meaning roughly equivalent to organics on a molar basis]; The molybdate is catalytic,” Benner responded.
“And borate has now been found in meteorites from Mars, that was reported about three months ago.
At his talk, Benner outlined some of the chemical reactions involved.
Although some scientists have invoked water, minerals and organics brought to ancient Earth by comets as a potential pathway to the origin of life, Benner thinks differently about the role of comets.
“Not comets, because comets do not have deserts, borate and molybdate,” Benner told Universe Today.
Benner has developed a logic tree outlining his proposal that life on Earth may have started on Mars.
“It explains how you get to the conclusion that life originated on Mars. As you can see from the tree, you can escape that conclusion by diverging from the logic path.”
Finally, Benner is not one who blindly accepts controversial proposals himself.
He was an early skeptic of the claims concerning arsenic based life announced a few years back at a NASA sponsored press conference, and also of the claims of Mars life discovered in the famous Mars meteorite known as ALH 84001.
“I am afraid that what we thought were fossils in ALH 84001 are not.”
The debate on whether Earthlings are really Martians will continue as science research progresses and until definitive proof is discovered and accepted by a consensus of the science community of Earthlings – whatever our origin.
On Nov. 18, NASA will launch its next mission to Mars – the MAVEN orbiter. Its aimed at studying the upper Martian atmosphere for the first time.
“MAVENS’s goal is determining the composition of the ancient Martian atmosphere and when it was lost, where did all the water go and how and when was it lost,” said Bruce Jakosky to Universe Today at a MAVEN conference at the University of Colorado- Boulder. Jakosky, of CU-Boulder, is the MAVEN Principal Investigator.
MAVEN will shed light on the habitability of Mars billions of years ago and provide insight on the origin of life questions and chemistry raised by Benner and others.
…………….
Learn more about Mars, the Origin of Life, LADEE, Cygnus, Antares, MAVEN, Orion, Mars rovers and more at Ken’s upcoming presentations
Sep 5/6/16/17: “LADEE Lunar & Antares/Cygnus ISS Rocket Launches from Virginia”; Rodeway Inn, Chincoteague, VA, 8 PM
Oct 3: “Curiosity, MAVEN and the Search for Life on Mars – (3-D)”, STAR Astronomy Club, Brookdale Community College & Monmouth Museum, Lincroft, NJ, 8 PM
Oct 9: “LADEE Lunar & Antares/Cygnus ISS Rocket Launches from Virginia”; Princeton University, Amateur Astronomers Assoc of Princeton (AAAP), Princeton, NJ, 8 PM
What’s new in the outer reaches of our solar system? Try the discovery of a Trojan asteroid orbiting Uranus. While a plethora of puns exist for this simple fact, the reality check is that this means there are far more of these objects out there than astronomers expected. The new Trojan even has a name – 2011 QF99!
A Trojan asteroid is a transient space rock which is temporarily captured by the gravity of a giant planet. It shares the planet’s orbital path, locked into a specific position known as a Lagrange point. What makes 2011 QF99 unusual is its presence in the outer solar system. Researchers found the scenario a bit unlikely. Why? The answer is simply because of planet size. According to theory, the strong gravitational pull of the larger neighboring planets should have destabilized any captured asteroid’s orbit and shot Uranian Trojans out of the neighborhood long ago.
So just how did this 60 kilometer-wide conglomeration of ice and rock end up circling Uranus? Astronomers turned towards computer modeling for the answer. The research team, including UBC astronomers Brett Gladman, Sarah Greenstreet and colleagues at the National Research Council of Canada and Observatoire de Besancon in France, did a simulation of the solar system and its co-orbital objects – including Trojan asteroids. A short-term animation showing the motion of 2011 QF99, as seen from above the north pole of the solar system can be found here.
“Surprisingly, our model predicts that at any given time three percent of scattered objects between Jupiter and Neptune should be co-orbitals of Uranus or Neptune,” says Mike Alexandersen, lead author of the study to be published tomorrow in the journal Science.
Until now, no one had made any estimates on the percentage of possible outer solar system Trojans. Unexpectedly, the amount ended up being far greater than earlier estimates. Just over the last 10 years, several temporary Trojans and co-orbitals have been cataloged and 2011 QF99 is one of them. It made its home around Uranus within the last few hundred thousand years and will eventually – in about a million years – escape Uranus’ gravity.
“This tells us something about the current evolution of the solar system,” says Alexandersen. “By studying the process by which Trojans become temporarily captured, one can better understand how objects migrate into the planetary region of the solar system.”
NASA has released some new photos and video animations outlining the concept of how their planned asteroid capture mission will work. The plan is to find, capture, redirect a near-Earth asteroid to a stable point near the Moon in order to explore and study it. As we’ve said previously, it’s still unclear if NASA will receive Congressional funding or authorization to do an asteroid retrieval mission, but the agency is moving ahead with its planning work for now.
NASA recently did a mission formulation review to look at some internal studies on the mission, as well as taking a look at over 400 ideas the space community submitted concerning the mission.
The new images show crew operations including the Orion spacecraft’s trip to and rendezvous with the relocated asteroid, as well as astronauts maneuvering through a spacewalk to collect samples from the asteroid.
You can watch the video and see more images below.
NASA is also looking at new technologies like a Solar Electric Propulsion System is an essential part of future missions into deep space with larger payloads. The use of advanced SEP offers more mission flexibility, NASA said.
If you’d like to get involved or add your input, NASA will host a technical workshop at the Lunar and Planetary Institute in Houston from Sept. 30 to Oct. 2 to discuss potential ideas. Virtual participation will be available to the public, and when the details of how to participate become available, Universe Today will post an update.