Search This Blog


Tuesday, June 28, 2011

Missed again

Near-Earth asteroid 2011 MD passed only 12,300 kilometers (7,600 miles) above the Earth's surface on Monday June 27 at about 1:00 PM EDT. The asteroid was discovered by the LINEAR near-Earth object discovery team observing from Socorro, New Mexico.

The diagram shows the trajectory of 2011 MD projected onto the Earth's orbital plane over a four-day interval. This small asteroid, only 5-20 meters in diameter, is in a very Earth-like orbit about the Sun. The incoming trajectory leg passed several thousand kilometers outside the geosynchronous ring of satellites and the outgoing leg passed well inside the ring.

Saturday, June 18, 2011

Dawn's Early Light

NASA's Dawn spacecraft is beginning to send back low-resolution photos of the asteroid Vesta. This is presently for navigational purposes, to help better steer Dawn toward its rendezvous with the asteroid. Once it gets close enough to start sending higher resolution images, I'll be posting about it here.

Almost as important as Dawn's mission is Dawn's means of accomplishing its mission. Dawn is not a traditional chemical rocket, but rather a prototype of an ion engine, which is about ten times more efficient. This is likely the next important step in propulsion systems for travel within our solar system.

Yesterday NASA announced new mission concept studies of solar electric propulsion, which is basically a solar-powered ion drive. Good on NASA; in this time of massive budgetary constraint, it's good to see them moving forward on this.

NASA Issues Announcement For Solar Electric Propulsion Studies

CLEVELAND -- NASA issued a Broad Agency Announcement (BAA) seeking proposals for mission concept studies of a solar electric propulsion system demonstration to test and validate key capabilities and technologies for future exploration missions.

Multiple studies have shown the advantages of using solar electric propulsion to efficiently transport heavy payloads from low Earth orbit to higher orbits. This concept enables the delivery of payloads to low Earth orbit via conventional chemical rockets. The use of solar electric propulsion could then spiral payloads out to higher energy orbits, including Lagrange point one, a potential assembly point in space between Earth and the moon. This approach could facilitate missions to near Earth asteroids and other destinations in deep space.

Science missions could use solar electric propulsion to reach distant regions of the solar system, and commercial missions could use solar electric propulsion tugs to place, service, resupply, reposition and salvage space assets. NASA's strategic roadmaps for exploration, science and advanced technology all consider solar electric propulsion a vital and necessary future capability.

NASA is examining potential mission concepts for a high-power solar electric propulsion system demonstration. Flying a demonstration mission on a representative trajectory through the Van Allen radiation belts and operating in actual space environments could reveal unknown systems-level and operational issues. Mission data will lower the technical and cost risk associated with future solar electric propulsion spacecraft. The flight demonstration mission would test and validate key capabilities and technologies required for future exploration elements such as a 300 kilowatt solar electric transfer vehicle.

This Solar Electric Propulsion Demonstration Mission Concept Studies announcement is open to all non-government United States institutions, academia, industry and nonprofit organizations. NASA anticipates making multiple firm-fixed-priced awards with a total value up to $2 million. The deadline for submitting proposals is July 18.

Thursday, June 16, 2011

Deep thoughts from a shallow mind

The Inside Passage runs northwest from the Northwest to Southeast, and southeast from Southeast to the Northwest.

I only flag this for the benefit of my navigation students, who often have great difficulty with the fact that the "Western Rivers" are all in the east.

I think I really need sleep.

Monday, June 13, 2011

Send your name to Mars!

Only a few hours left! Very cool.

Rocks and Buggys

The best direct evidence we have to date of extraterrestrial life is in the form of microscopic inclusions in a small number of carbonaceous meteorites, which have the appearance of being fossilized prokaryotes. By far the best known of these is ALH 84001, the martian meteorite found in Allan Hills Antarctica in 1984.

Earlier this year NASAjavascript:void(0)/Huntsville scientist Richard Hoover announced that a number of non-martian meteorites also contain possible fossil prokaryotes. Below is both his abstract and a link to the entire paper in Journal of Cosmology.

Okay. So, I happen to like JoC. It's one of the many links from this blog, and I really like their philosophy of ensuring that all of the papers they publish are available to anyone free of charge. Most similar outlets only publish the abstracts free of charge. So, good on them for this. And good on them for maintaining some semblance of a peer-review process.

The bad news with JoC is that they have a very openly anti-scientific agenda, which tends to lead to the occasional publication of some really, really shoddy research. Regarding Hoover's work, they state that "Hoover's paper is further evidence that life is pervasive in this galaxy and exists on astral bodies other than Earth. The alternative view is life exists only on Earth, and originated on Earth, as described in the Jewish and Christian Bible and which is the official position at NASA. We believe the choice is simple: Religion vs Science. The Journal of Cosmology is devoted to promoting science."

This philosophy steers many of the papers published in JoC. Up to and including denying the Big Bang, not on the basis of any solid evidence but rather on the basis that it looks a little bit like Genesis and that Georges Lemaître happened to be a Catholic priest. Really. Presumably gene theory is also not "science" as JoC imagines that, because Gregor Mendel was an Augustinian monk.

JoC is in no way unique in this. Capital "S" Science, like capital "A" Atheism, is simply another fundamentalist religion, with its own canon world-views and orthodoxies and hence necessary heresies. It has adopted the old fundamentalist Christian mantra of "don't open your mind, your brains might leak out"; I consider "Science" to be one of the greatest threats to rational critical thought, and legitimate science, in our culture today.

Just because the Bible says something doesn't mean that it's categorically true. Just because the Bible says something also doesn't mean that it's categorically untrue. It's just a freaking book.

I'm not sure why Richard Hoover, a respected NASA scientist, did not publish his research through NASA, and instead published through the Journal of Cosmology. It doesn't exactly help his credibility. For the record, I think he's mostly right, and that NASA would have published his work, so I can only assume that his decision not to was political rather than scientific.

In any event, here is his paper. The entire thing is linked at the bottom.


Fossils of Cyanobacteria in CI1 Carbonaceous Meteorites:
Implications to Life on Comets, Europa, and Enceladus

Richard B. Hoover,
Space Science Office, Mail Code 62, NASA/Marshall Space Flight Center, Huntsville, AL 35812

Environmental (ESEM) and Field Emission Scanning Electron Microscopy (FESEM) investigations of the internal surfaces of the CI1 Carbonaceous Meteorites have yielded images of large complex filaments. The filaments have been observed to be embedded in freshly fractured internal surfaces of the stones. They exhibit features (e.g., the size and size ranges of the internal cells and their location and arrangement within sheaths) that are diagnostic of known genera and species of trichomic cyanobacteria and other trichomic prokaryotes such as the filamentous sulfur bacteria. ESEM and FESEM studies of living and fossil cyanobacteria show similar features in uniseriate and multiseriate, branched or unbranched, isodiametric or tapered, polarized or unpolarized filaments with trichomes encased within thin or thick external sheaths. Filaments found in the CI1 meteorites have also been detected that exhibit structures consistent with the specialized cells and structures used by cyanobacteria for reproduction (baeocytes, akinetes and hormogonia), nitrogen fixation (basal, intercalary or apical heterocysts) and attachment or motility (fimbriae). Energy dispersive X-ray Spectroscopy (EDS) studies indicate that the meteorite filaments are typically carbon rich sheaths infilled with magnesium sulfate and other minerals characteristic of the CI1 carbonaceous meteorites. The size, structure, detailed morphological characteristics and chemical compositions of the meteorite filaments are not consistent with known species of minerals. The nitrogen content of the meteorite filaments are almost always below the detection limit of the EDS detector. EDS analysis of terrestrial minerals and biological materials (e.g., fibrous epsomite, filamentous cyanobacteria; mummy and mammoth hair/tissues, and fossils of cyanobacteria, trilobites, insects in amber) indicate that nitrogen remains detectable in biological materials for thousands of years but is undetectable in the ancient fossils. These studies have led to the conclusion that the filaments found in the CI1 carbonaceous meteorites are indigenous fossils rather than modern terrestrial biological contaminants that entered the meteorites after arrival on Earth. The δ13C and D/H content of amino acids and other organics found in these stones are shown to be consistent with the interpretation that comets represent the parent bodies of the CI1 carbonaceous meteorites. The implications of the detection of fossils of cyanobacteria in the CI1 meteorites to the possibility of life on comets, Europa and Enceladus are discussed. Keywords: Origins of life, CI1 meteorites, Orgueil, Alais Ivuna, microfossils, cyanobacteria, comets, Europa, Enceladus

Saturday, June 11, 2011

ISS and Endeavor

European Space Agency--
This image of the International Space Station with the docked Europe's ATV Johannes Kepler and Space Shuttle Endeavour was taken by Expedition 27 crew member Paolo Nespoli from the Soyuz TMA-20 following its undocking on 24 May 2011. The pictures are the first taken of a shuttle docked to the ISS from the perspective of a Russian Soyuz spacecraft. Onboard the Soyuz were Russian cosmonaut and Expedition 27 commander Dmitry Kondratyev, ESA's Paolo Nespoli and NASA astronaut Cady Coleman. Coleman and Nespoli were both flight engineers. The three landed in Kazakhstan later that day, completing 159 days in space.

Credits: ESA/NASA

Full Resolution:

Monday, June 6, 2011

Commander Mark

A very cool thing happened last night.

The Irish band U2 played in Seattle. Not altogether unusual, Seattle gets good bands all the time. But the band did something kind of unusual, which they had apparently been planning long before it would have had quite the significance that it did. One of their "guests" was a live feed from the International Space Station, intended to raise awareness of NASA's ongoing mission and the importance of our continued presence in space. This has been an ongoing part of U2's tour this year. That would have been cool enough.

But the astronaut who spoke to the crowd last night was Commander Mark Kelly, husband of congresswoman Gabby Giffords.

Kelly finished his piece with "Tell my wife I love her very much...she knows". I can't imagine that there was a dry eye in Qwest Field. I hope David Bowie was listening.

I was five years old when Neil Armstrong, Buzz Aldrin and Michael Collins became the first humans to voyage to another world. When I was five years old, astronauts were my heroes.

They still are. I just have a deeper understanding now of what heroism is.

Thursday, June 2, 2011


The question of how life originally arose on earth is of particular significance both to those searching for extraterrestrial life and to those searching for habitable worlds which are devoid of life.

Mythology withstanding, there are four likely possibilities of how life first arose on earth.

The first is anomalous abiogenesis, meaning that life arose from non-life in a single instance, and that all life on earth descended from that unique prototypical life form.

The second is non-anomalous abiogenesis, meaning that when the conditions are correct life tends to occur spontaneously and ubiquitously. In this case, the two existing domains of prokaryotes (bacteria and archae) were of completely different abiogenetic origin, and presumably other independent forms of prokaryotic life existed at one time but were out-competed early in earth's prehistory.

The third and fourth are anomalous and non-anomalous panspermia. This is the idea that prokaryotic life arrived on earth from space, likely ensconced in meteorites. There is a substantial amount of material support for this theory, which this series will explore in some detail. Panspermia does not answer the the question of how life originated in the first place, but for our purposes that concern is frankly secondary.

It is also of course possible that terrestrial life arose both on earth and from space. But determining which contemporary organisms are native and which are descended from aliens may not be knowable until we have unequivocally extraterrestrial organisms to compare them to.

The essence of this question is simply this: how rare or ubiquitous is life in our solar system and beyond? And if life beyond our atmosphere is not rare, how exotic or mundane is that life? We are now, possibly, starting to have some answers to these questions. These answers, and their implications, will be the subject of the next several posts.


Regarding the next week or so of posting, I will be out of the state and away from any real computer for much of the next week. Will post as much as possible via Android phone; many apologies in advance for the typos. There will be many.

Wednesday, June 1, 2011

Ready about

So, here's where things stand with the discussion of Orion, DARPA's "100 year starship".

We currently have the technology to build a ship which could reach Alpha Centauri in 88 years.

In the context of this series on outmigration, our primary purpose in doing so is to migrate some small portion of the human gene pool off-world, to enhance the possibility of our continued survival as a species. This seems to be one of DARPA's purposes as well.

In order for Alpha Centauri to actually warrant traveling to it, we would need to know beforehand that a world exists in that system which is significantly more hospitable than Mars or other locations in our solar system, but devoid of life.

We will likely have the ability to determine this with some confidence in the coming decade. The existence or non-existence of an earth-sized world with a significant amount of liquid water on its surface will probably be known within the next few years, assuming that the Exo-Earth Imager telescope is completed.

If no such world is found, then the search would shift to Barnard's Star. If Barnard's Star proved similarly devoid of habitable worlds, Orion will almost certainly not be built. At least, not the interstellar version of Orion. There would simply be no point.

Assuming that a suitable world is found, determining the existence of life will prove more challenging, but high concentrations of atmospheric oxygen or methane on a temperate world would be a pretty good first clue. If we should find conclusive evidence of life on such a world, that would immediately shift the focus away from colonization toward very cautious exploration. Because a war of the worlds, even unintentional and even on a microbial scale, is likely to end badly for everyone involved.

If our hypothetical "goldilocks world" should prove mostly habitable but uninhabited, the first priority of the new colonists will be terraforming it from "mostly habitable" to truly earth-like. By definition, any world worthy of traveling four lightyears to terraform should be pretty quick and simple to terraform. A need for much more than simple oxygenation of the atmosphere (by photosynthetic or chemical means) would tip the balance back in favor of Mars or Europa for permanent colonization. But we cannot begin to estimate what steps would be necessary for terraformation until we have a pretty good understanding of the world as it currently exists. And until we know those steps, and what resources we can hope to find on that world to help accomplish those steps, we have no way of determining how much of the cargo space of the Orion vessel would be committed to carrying either materiel for terraformation, or equipment for surviving on a non-terraformed world.

This brings us to something of an impasse. We have the technology and resources to build the working parts of Orion. But we do not yet have the knowledge to determine what to carry in it, and for a one-way sojourn to the nearest stars, we cannot leave that to guesswork. Until the Exo-Earth Imager is operational, and we have real data about the planetary systems of Alpha Centauri and Barnard's Star, we cannot proceed much further on this tack.

The good news is, if all goes well we may have the answers we need much sooner than we would realistically begin building Orion.

In the mean time, we have left an enormous question unanswered which is critical for human colonization not only of the stars, but of the other worlds within our own solar system. Our quest for a habitable-but-uninhabited world raises the question of how in fact life arises on a world, and how common this process actually is. So I want to take this discussion on a different tack for a bit, and look at how life arose on earth, and how likely it is that life has arisen elsewhere. For the next several posts I'm going to look at abiogenesis, panspermia, and exobiology generally.

Helm's a lee.