On Monday, I appeared on RT America’s live news broadcast to talk exoplanets — particularly the three small (possibly rocky) worlds that orbit the stars Kepler-62 and Kepler-69. It was a lot of fun discussing ‘Goldilocks Zones’ and the possibilities of extraterrestrials. Enjoy!
Discovery News coverage of Kepler-62:
Apollo 11 Commander Neil Armstrong inside the lunar module “Eagle” after his first moonwalk. Credit: NASA
“The important achievement of Apollo was demonstrating that humanity is not forever chained to this planet and our visions go rather further than that and our opportunities are unlimited.” –Neil Armstrong
Discovery News:
BIG PIC: Neil Armstrong, Apollo Legend, Has Died
PHOTOS: Remembering Neil Armstrong: Humanity’s Hero
The magnetic loop containing hydrogen and nitrogen plasma evolves over 4 micro-seconds. Credit: Bellan & Stenson, 2012
There’s no better method to understand how something works than to build it yourself. Although computer simulations can help you avoid blowing up a city block when trying to understand the physics behind a supernova, it’s sometimes just nice to physically model space phenomena in the lab.
So, two Caltech researchers have done just that in an attempt to understand a beautifully elegant, yet frightfully violent, solar phenomenon: coronal loops. These loops of magnetism and plasma dominate the lower corona and are particularly visible during periods of intense solar activity (like, now). Although they may look nice and decorative from a distance, these loops are wonderfully dynamic and are often the sites of some of the most energetic eruptions in our Solar System. Coronal loops spawn solar flares and solar flares can really mess with our hi-tech civilization.
A coronal loop as seen by NASA’s Transition Region and Coronal Explorer (TRACE). Credit: NASA
In an attempt to understand the large-scale dynamics of a coronal loop, Paul Bellan, professor of applied physics at Caltech, and graduate student Eve Stenson built a dinky “coronal loop” of their own (pictured top). Inside a vacuum chamber, the duo hooked up an electromagnet (to create the magnetic “loop”) and then injected hydrogen and nitrogen gas into the two “footpoints” of the loop. Then, they zapped the whole thing with a high-voltage current and voila! a plasma loop — a coronal loop analog — was born.
Although coronal loops on the sun can last hours or even days, this lab-made plasma loop lasted a fraction of a second. But by using a high-speed camera and color filters, the researchers were able to observe the rapid expansion of the magnetic loop and watch the plasma race from one footpoint to the other. Interestingly, the two types of plasma flowed in opposite directions, passing through each other.
The simulation was over in a flash, but they were able to deduce some of the physics behind their plasma loop: “One force expands the arch radius and so lengthens the loop while the other continuously injects plasma from both ends into the loop,” Bellan explained. “This latter force injects just the right amount of plasma to keep the density in the loop constant as it lengthens.” It is hoped that experiments like these will ultimately aid the development of space weather models — after all, it would be useful if we could deduce which coronal loops are ripe to erupt while others live out a quiescent existence.
It’s practical experiments like these that excite me. During my PhD research, my research group simulated steady-state coronal loops in the hope of explaining some of the characteristics of these fascinating solar structures. Of particular interest was to understand how magnetohydrodynamic waves interact with the plasma contained within the huge loops of magnetism. But all my research was based on lines of code to simulate our best ideas on the physical mechanisms at work inside these loops. Although modelling space phenomena is a critical component of science, it’s nice to compare results with experiments that aim to create analogs of large-scale phenomena.
The next test for Bellan and Stenson is to create two plasma loops inside their vacuum chamber to see how they interact. It would be awesome to see if they can initiate reconnection between the loops to see how the plasma contained within reacts. That is, after all, the fundamental trigger of explosive events on the Sun.
Read more in my Discovery News article: “Precursors to Solar Eruptions Created in the Lab“
Hi-res self-portrait of Curiosity — taken with the mast-mounted Navcams. Debris can be seen scattered across the deck. Credit: NASA/JPL-Caltech
During Mars rover Curiosity’s dramatic landing on Aug. 5, the rocket-powered sky crane blasted debris onto the rover’s deck. The first question that came to mind concerned the safety of exposed and potentially vulnerable instrumentation. I was in the very fortunate position to raise my concerns during the Aug. 9 NASA news briefing. The response from MSL mission manager Mike Watkins was cautious optimism that little to no damage was caused by the unexpected ejection of material from the ground.
Alas, it would seem that some damage was sustained.
“It does appear that some small rocks became lofted in the winds that were generated by the plumes during landing and probably just fell upon the rover deck,” said Curiosity deputy project scientist Ashwin Vasavada, with NASA’s Jet Propulsion Laboratory in Pasadena, Calif., during a conference call on Tuesday (Aug. 21).
“Some of these rocks may have fallen on these exposed circuit boards and damaged the wires. That’s just one potential cause. We don’t know for sure and we don’t really have a way of assessing that at this point any further,” he added.
It appears that one of the booms on the Mars Science Laboratory’s Rover Environmental Monitoring Station (REMS) — located on the rover’s mast — may have been the hardware that got sandblasted or smashed by Mars rocks. REMS now only has one (of two) booms operational. The booms’ purpose is to take measurements of wind speed on the Martian surface. Although this is a setback (and, so far, the ONLY setback), mission scientists are confident they’ll find a workaround.
“We’ll have to work a little harder to understand when the wind may be coming from a direction that would be masked by (Curiosity’s) mast … but we think we can work around that,” Vasavada said.
So, it would appear that Mars shot first… but Curiosity shot back. (Thanks @absolutspacegrl and @ArchLundy!)
@astroengine Mars shot first?#pewpew— Holly (@absolutspacegrl) August 22, 2012
@astroengine So actually the rocks shot first.— Arch Lundy (@ArchLundy) August 22, 2012
Just in case you have no idea what we’re referring to:
M104, “The Sombrero Galaxy” as seen through the DCT. Credit: Lowell Observatory/DCT
Since I started working as Space Producer at Discovery News in 2009, there’s always been a major project humming in the background. But on Saturday, that hum evolved into a monster roar when astronaut legend Neil Armstrong spoke at Lowell Observatory, near Flagstaff, Ariz., to introduce the $53 million 4.3-meter Discovery Channel Telescope. Seeing photographs of the ‘scope and its “first light” observations gave me goosebumps.
But this is only the beginning. As the fifth largest optical telescope in the continental USA, the DCT has a packed science schedule and I am in a very privileged position to report on the exciting discoveries that will be made by “our” telescope.
Congratulations to everyone at Lowell Observatory on a job well done!
More:
BIG PICS: The DCT First Light Gallery.
PHOTOS: Get a behind-the-scenes tour of the Discovery Channel Telescope.
INTERVIEW: Unlocking dwarf galaxy mysteries with the DCT — Discovery News talks with Lowell Observatory astronomer Deidre Hunter.
WHAT OTHERS ARE SAYING:
Cosmic Log — Alan Boyle — Telescope opens a brand new window on Discovery
Bad Astronomy — Phil Plait — Discovery Channel telescope sees first light!
This video has been doing the rounds, so I posted it on Discovery News on Tuesday. My favorite comment from a reader was: “I need a clean pair of shorts.” That means only one thing; it’s time for some epic NASA-created CGI of the entry, descent and landing (a.k.a. “EDL”) of the Mars Science Laboratory “Curiosity” set for landing on the Red Planet on August 5 at 9:30 p.m. (PST). To be honest, the video speaks for itself, so I’ll hand over to EDL Engineer Adam Stelzner (who really needs his own TV show — love his monolog).
A menagerie of strange divots (NASA/HiRISE/Univ. of Arizona)
As 2011 draws to a close, it’s time to reflect on my absenteeism from Astroengine. But it’s not my fault, I’ve been typing like a madman for these guys.
But that’s enough excuses, 2012 promises to be a huge year for space, and if I get my time management skills back up to scratch, there will be a whole lot more of the blogging thing going on over here too. So to kick things off I thought I’d share a cool slide show I’ve been working on for Discovery News with Ari Espinoza of the High-Resolution Imaging Science Experiment (HiRISE) — the awesome camera currently orbiting Mars aboard NASA’s Mars Reconnaissance Orbiter (MRO).
With the help of Ari, we managed to collect some weird-looking Mars craters (for the hell of it) and create a slide show with some of the strangest. Below are a few of my favorites, but be sure to check out the full slide show for more oddities!
Some galaxies undergo a rapid star formation phase, losing stellar gases to intergalactic space, others choose to recycle, thereby extending their star forming lifespans (NASA, ESA, and A. Feild (STScI))
It sounds like an over-hyped public service announcement: If you don’t recycle, you’ll die a premature death.
But in the case of galaxies, according to three new Science papers based on Hubble Space Telescope data, this is a reality. Should a galaxy “go green,” reusing waste stellar gas contained within huge halos situated outside their visible disks, they will fuel future star-birth cycles, prolonging their lifespans.
Sadly for “starburst” galaxies — galaxies that undergo rapid star generation over very short time periods — they care little for recycling, resulting in an untimely death.
Using data from Hubble’s Cosmic Origins Spectrograph (COS), three teams studied 40 galaxies (including the Milky Way) and discovered vast halos of waste stellar gases. Contained within these spherical reservoirs — extending up to 450,000 light-years from their bright disks of stars — light elements such as hydrogen and helium were found to be laced with heavier elements like carbon, oxygen, nitrogen and neon. There’s only one place these heavy elements could have come from: fusion processes in the cores of stars and supernovae.
Interestingly, the quantity of heavy elements contained within the newly-discovered halos is similar to what is contained in the interstellar gases within the galaxies themselves.
“There’s as much heavy elements out in the halos of the galaxies as there is in their interstellar medium, that is what shocked us.” said Jason Tumlinson, an astronomer for the Space Telescope Science Institute in Baltimore, Md., in an interview for my Discovery News article “Galaxies That Don’t Recycle Live Hard, Die Young.”
But these heavy elements are stored in halos outside the galaxies; how the heck did it get there?
According to the researchers, powerful stellar winds jetting into intergalactic space have been observed, transporting the heavy elements with them. But there’s a catch. If the outflow is too strong, waste stellar gases are ejected from the galaxies completely. Unfortunately for one sub-set of galaxies, powerful stellar outflows come naturally.
Starburst galaxies rapidly generate stars, ejecting speedy streams of stellar waste gas. Some of these streams have been clocked traveling at 2 million miles per hour, escaping from the galaxy forever. In the case of a starbust galaxy, a “recycling halo” cannot be re-supplied — future star birth is therefore killed off.
“We found the James Dean or Amy Winehouse of that population, you know, the galaxies that lived fast and died young,” Tumlinson pointed out. “(Todd) Tripp’s team studied that in their paper.”
“That paper used a galaxy that is known as a ‘post-star burst galaxy’ and its spectrum showed that it had a very robust star burst (phase),” he continued. “It was one of those live fast, die young galaxies.”
Although fascinating, one idea struck me the hardest. On asking Tumlinson to speculate on how galactic recycling of stellar material may impact us, he said:
“Your body is 70 percent water and every water molecule has an oxygen atom in it. The theorists say the recycling time (in the Milky Way’s halo) is approximately a billion years, so that means — potentially — that some of the material (oxygen) inside your body has cycled in and out of the galaxy ten times in the history of the galaxy. At least once, maybe up to ten times.”
As Carl Sagan famously said: “We’re made of star stuff;” perhaps this should be rephrased to: “We’re made of recycled star stuff.”
Publications:
"That's no sunspot."
Assuming Star Trek‘s Borg Collective went into overdrive and decided to build a huge cube a few thousand miles wide, then yes, the exoplanet-hunting Kepler space telescope should be able to spot it. But how could Kepler distinguish a cube from a nice spherical exoplanet?
With the help of Ray Villard over at Discovery News, he did some digging and found a paper dating back to 2005 — long before Kepler was launched. However, researcher Luc Arnold, of the Observatoire de Haute-Provence in Paris, did have the space telescope in mind when he studied what it would take to distinguish different hypothetical shapes as they passed in front of his theoretical stars.
The big assumption when looking for exoplanets that drift between distant stars and the Earth — events known as “transits” — is that the only shape these detectable exoplanets come in are spheres. Obvious really.
As a world passes in front of its parent star, a circular shadow will form. However, from Earth, we’d detect a slight dimming of the star’s “light curve” during the transit, allowing astronomers to deduce the exoplanet’s orbital period and size.
The transit method has been used to confirm the presence of hundreds of exoplanets so far, and Kepler has found over 1,200 additional exoplanet candidates. But say if astronomers paid closer attention to the shape of the received light curve; spherical objects have a distinct signature, but say if something looked different in the transiting “planet’s” light curve? Well, it could mean that something non-spherical has passed in front of a star. And what does that mean? Well, that would be a pretty convincing argument for the presence of a huge planet-sized artificial structure orbiting another star. Artifical structure = super-advanced alien civilization.
Arnold tested his theory that all manner of shapes could be detected by Kepler, assuming the transiting structure was on the scale of a few thousand miles wide. In this case, Arnold was testing his hypothesis to see whether we could detect an advanced civilization’s “shadow play.” Perhaps, rather than beaming messages by radio waves, an advanced civilization might want to signal their presence — SETI style — by blocking their sun’s light with vast sheets of lightweight material. As the shape passes in front of the star, the slight dimming of starlight would reveal an artificial presence in orbit.
By putting a series of these shapes into orbit, the aliens could create a kind of interstellar Morse code.
Of course, this is a rather “out there” idea, but I find it fascinating that Kepler could detect an alien artifact orbiting a star tens or hundreds of light-years away. Although this research is only considering orbital “billboards,” I quite like the idea that Kepler might also be able to detect a large structure like… I don’t know… a big Borg mothership. Having advanced warning of the presence of an aggressive alien race sitting on our cosmic doorstep — especially ones of the variety that like to assimilate — would be pretty handy.
Publication: Transit Lightcurve Signatures of Artificial Objects, L. Arnold, 2005. arXiv:astro-ph/0503580v1
"Dad?" A scene from War of the Worlds.
This rather outlandish, sci-fi notion comes straight from the fertile minds of researchers from MIT, the Massachusetts General Hospital and Harvard University who are proposing a biology experiment that could be sent on a future Mars surface mission. If their hypothesis is proven, we wouldn’t only have an answer for the age old question: Are we alone? but we’d also have an answer for the not-so-age-old question: Did life from Mars spawn life on Earth?
The idea goes like this: countless tons of material from Mars has landed on Earth. We know this to be true; meteorites have been discovered on Earth that originate from the Red Planet. These rocks were blasted from the Martian surface after eons of asteroid impacts, and the rocks then drifted to Earth.
If there was once life on Mars — a concept that isn’t that far-fetched, considering Mars used to boast liquid water in abundance on its surface — then perhaps some tiny organisms (not dislike the hardy cyanobacteria that is thought to have been one of the earliest forms of life to evolve on our planet) hitched a ride on these rocks. If some of these organisms survived the harsh conditions during transit from Mars to Earth and made it though the searing heat as the meteorite fell through our atmosphere, then perhaps (perhaps!) that is what sparked life on Earth.
You may have heard a few variations of this mechanism, it is of course the “panspermia” hypothesis. Panspermia assumes that life isn’t exclusive to just one rocky body like Earth, perhaps life has the ability to hop from one planet to the next, helped on its way by asteroid impacts. Not only that, but perhaps (perhaps!) tiny microorganisms could drift, encased in interstellar dust, akin to pollen drifting in the wind, seeding distant star systems.
Naturally, when considering the distance between the planets (let alone the light-years between the stars!), one might be a little skeptical of panspermia. But it certainly would help us understand how life first appeared on Earth. After all, it’s not as if the solar system has a natural quarantine system in place — if Mars had (or has) bacteria on its surface, perhaps they have been spread to Earth, like an interplanetary flu bug. Also, as experiments are showing us, microorganisms have an uncanny ability to survive in space for extended periods of time.
So, according to my esteemed Discovery News colleague Ray Villard, the MIT team led by Christopher Carr and Maria Zuber and Gary Ruvkun, a molecular biologist at the Massachusetts General Hospital and Harvard University, are proposing to build an instrument to send to Mars. But this instrument won’t be looking for signs of life, it will be testing the hypothetical Martian DNA and RNA. Should this interplanetary paternity test prove positive, proving a relationship between Earth Brand™ Life and Mars Brand™ Life, then this could be proof of some extraterrestrial cross-pollination.
Although this is complete conjecture at this time, as there is no proof that life has ever existed on Mars (despite what research in dodgy research journals tell us), it is certainly an interesting idea that would not only test the hypothesis of panspermia, but also give us a clue about the potential human colonization of Mars.
This could give us pause about sending humans to a germ-laden alien world. It would be an ironic twist on the H.G. Wells classic 1898 novel “The War of the Worlds,” where invading Martians succumb to the common cold from Earth microbes.
See, Wells’ Martian warriors should have done genome testing first.
