November 22, 2017

Astronomy Video of the Week: Astrophe

Yearning to break the surly bonds…

(photo by author).

It’s a feeling that every lover of space has sometimes.

Exploration of the cosmos is truly a final frontier, a place that often seems to be our logical destiny. But sometimes, there’s a persistent nagging at the back of our primate brains, a feeling that, just maybe, the learning curve is too steep, and maybe space is too hard… perhaps, this still unquiet voice says, the true reason that we never hear from alien civilizations is that this final crucible of leaving the planetary cradle is just too tough. [Read more...]

Review: Packing for Mars by Mary Roach.

Consider our bags packed!

Behind every modern day manned mission to space is a fascinating tale of how we got there and what it’s truly like to live and work in such a bizarre and hostile environment. If the average American does bother to watch NASA TV, they rarely stop to think of what amount of planning and preparation goes in to putting humans into space. [Read more...]

26.05.11: Farewell, Spirit…

Spirit: A self-portrait. (Credit: NASA/JPL).

This week, amid news of distant gamma ray bursts, daring spacewalks, and spacecraft redesigns, a small story came our way of the end of an era; earlier this week, NASA announced that it would no longer attempt to hail the Spirit Lander on the surface of Mars. [Read more...]

17.03.11- Mercury: At Last!

Brave New World: Mercury as seen from Messenger during 2nd flyby departure.

 (Credit: NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington) 

Tonight marks a pivotal moment in solar system exploration. At 12:45 AM UTC on March 18th, NASA’s Mercury Messenger spacecraft will burn its engines for approximately 15 minutes to enter an elliptical orbit around the planet Mercury. Since its launch from Cape Canaveral on August 3rd, 2004, Messenger has flown by the Earth once and Venus twice for a gravitational assist, swung by the innermost world three times, sampled the near solar environment, searched for Vulcanoids, and even done a wide field pan for any tiny Mercury moonlets that may have been missed. [Read more...]

10.03.11: A Planetary Exploration Wish List.

What extra cool orbiters or landers would you like to see funded? Earlier this week, the National Research Council’s Space Studies Board unveiled its exhaustive 400 page report that outlines a vision for unmanned space exploration of the solar system from 2013 through 2022. This was presented at the ongoing Lunar & Planetary Science Conference, and as suspected there were big winners, a few potential losers, and a lot of maybes that have to whittle down their budget-busting prices a bit.

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02.03.11: Rise of the Robonauts.

The International Space Station (ISS) has a new permanent resident, one that will assist astronauts and become a valued member of the space station team. Robonaut 2 (R2) arrived at the ISS this week, delivered by STS-133 on the final flight of the Space Shuttle Discovery. Initially, Robonaut 2 will be a stationary resident, to be installed in the Unity Node until it can perform more complex mobile tasks.

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Near Earth Objects: Mitigating the Threat.

(Editor’s Note: What follows is a scenario/article along with an original lesson plan re-written for a blog format).

Arizona Meteor Crater… x100=a bad day for the Earth? (Photo by Author).

Eventually, it had to happen. With scant warning, the announcement is made that a large space rock is inbound to strike Earth and is only weeks away. The news largely takes the public by surprise; this is the big one, an extinction class event. People are exasperated to learn that little can be done to deflect the large impactor; all that remains is for scientists to predict the precise impact location and for world organizations to attempt evacuations so that some of humanity might survive… [Read more...]

27.05.10: A New Resident for the ISS.

 

Introducing...Robonaut 2. (Credit: NASA/JSFC).

Introducing...Robonaut 2. (Credit: NASA/JSFC).

 

    The final flight of shuttle Discovery STS-133 will carry a new permanent resident to the station; a robotic assistant known as Robonaut 2.  A joint NASA-General Motors design, Robonaut 2 looks like a life-sized Micronaut and will carry out routine tasks around the International Space Station. Currently undergoing testing at the Johnson Space flight center, Robonaut 2 will initially be tethered to the Destiny module aboard the ISS, although it (he?) will eventually receive more autonomy as proficiency increases. Robonaut 2 will perform such routine maintenance tasks as cleaning, housekeeping and setting up experiments. No word has been given if Robonaut will do any external station work, but of course, such a hazardous environment would be well suited to it. Arrival of Robonaut 2 aboard the ISS will be followed by a lengthy checkout in zero-g. Robonaut 2 may have a humanoid appearing upper torso, but will be able to interchange (Transformers fans take note) with a variety of lower bodies; the ISS version will perhaps sport one anchoring leg, but wheeled planetary rover bodies are envisioned. “R2” (we can hear the bad late night jokes now!) will have a 40 lb payload capacity, and a grasp of 5 lbs per finger. And before you comment that “objects don’t have weight in space,” let me remind you that they still have inertia. (Bazzinga!)

So, what will the astronauts think of this “robo-butler?” Will they name it, pose for pictures with it, and/or play chess with it? NASA has no official plans to make the robot interactive, although Robonaut Project Manager Ron Diftler says this would be relatively easy to do. And it would also provide good PR for NASA, at least until folks start worrying that their Roombas and Blue-ray players might rise up. Still, instead of a showdown scenario such as the one with Hal 9000 portrayed in 2001, Robonaut may prove to be an astronauts’ greatest ally, such as in last years’ indie flick Moon.  Versions of Robonaut may be common place and even mandatory residents in the spacecraft of the future, as we move beyond Low Earth Orbit and out into the solar system… can’t you just hear the call, “R2, try and increase the power…”

Review: How to Build a Habitable Planet by James Kasting.

Some years ago, a book entitled Rare Earth was published amid much controversy. The central thesis of this work was that events that led to the eventual habitability and diversity of life and intelligence on Earth were so improbable, as be near to impossible to replicate elsewhere in our galaxy. The book marked a sort of change in thinking in the realm of exobiology, one from “intelligent civilizations are everywhere” championed by the late Carl Sagan to the concept that we may be the only ones, if not the first.

Out now from Princeton Press!
Out now from Princeton Press!


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27.04.10-Does Planetary Gravity “Stir up” Asteroids?

(Credit: Hayabusa/JAXA).

(Credit: Hayabusa/JAXA).

 The bizzare world of Itokawa as seen from Hayabusa.

   Asteroids are probably the most intriguing bodies in our solar system. More than just errant chucks of rock, these tiny worlds may hold the key to early planetary accretion. Several mysteries about these bodies persist; are they single slabs of rock, or loosely held together rubble piles? The question may be more than just an academic one, especially if we want to move one of these celestial missiles headed our way. Now, researcher Rick Binzel of MIT has noted a curious factor about many Near Earth Asteroids (NEA’s); nearly all which have experienced close passages near the Earth have seemed to undergo a spectral change. Specifically, the study looked at simulations of the orbits of 95 NEAs. Most are of the S-type, showing a reddish, sun burnt spectrum indicative of solar wind blasting for several million years. About 20, however, show a Q-type resurfacing, as if they had been “freshened up” somehow. Q-type asteroids are of the same spectral class as ordinary chondrite meteorites found on Earth, and are almost never observed in the main asteroid belt. Tracing back their orbits, all 20 show evidence of passages closer to the Earth than our Moon sometime in their history. Scientist Pierre Vernazza of the European Space Agency estimates that asteroids can be reddened by solar wind exposure in about one million years. Looking at asteroids such as 25143 Itokawa imaged by the Japanese Space Agencies’ Hayabusa spacecraft, one can easily imagine such a loose collection of rock experiencing massive landslides as it passes the massive Earth. Such an event may even splinter the main body, as happened to comet Shoemaker-Levy 9 in 1992 when it was torn apart and ultimately impacted Jupiter. And we have an unprecedented opportunity to study an NEA in 2029, when asteroid 99942 Apophis swings by Earth at a distance of about 20,000 miles above our surface. “My vision is that we would have (Apophis) all wired up and monitored so that we can listen to it creak and groan as it flies by,” says Binzel. Knowing what kind of shifting terrain they face might also be of vital importance to future visiting astronauts. A mission to such a body was stated by president Obama in a recent address given at the Kennedy Space Center. Clearly, these bodies are of unparalleled interest… all eyes will be on the Australian desert on June 13th of this year as Hayabusa returns to Earth. Did it successfully grab a sample of an NEA? Researchers won’t know for sure until they have the sample return canister in hand!

26.04.10-Amateurs Scour the Solar System.

marshorizon_opportunity

A stunning Martian panorama! (Credit:NASA/JPL Image Processing by Michael Howard & Glen Nagle).

   A quiet sort of revolution has been brewing online. Amateur astronomers have taken to the web on cloudy, light polluted nights and turned newly found computing power normally reserved for gaming and Second Life into something truly productive and phenomenal; the reprocessing of planetary images. This link includes more examples than you can shake a robotic camera arm at; the data is culled not only from the raw image archives of older spacecraft such as Mariner 10 and Voyager 2, but newer generation spacecraft such as the Cassini orbiter around Saturn and the Mars Exploration Rover Opportunity pictured above. These images frequently circulate the web and are processed and discussed long before even NASA engineers get to them. And with the mounting number of new missions out there and the transparency and access to public data increasing, the trend is likely to continue. But beyond just pretty pictures, the images dug up often have real scientific merit and value as well; for example, Philosophy professor Ted Stryk actually caught Neptune’s tiny moon Despina in the act of transiting as he sifted through old Voyager data! This makes one wonder; what else might engineers and scientists have missed? Emily Lakdawalla, web editor for the Planetary Society has contributed extensively to this growing revolution of online citizen scientists, taking advantage of Cassini’s equinox mission to produce some stunning images. So give it a try; put that ultimate power sitting idle on your desk to work doing something useful and productive… you just might spot that unknown moon or monolith!

neptune_despina_transit_combo_despinabrightened

A sight never before seen from Earth; the transit of Neptune’s moon Despina! (Credit: NASA/JPL Image processing & Copyright: Ted Stryk).

22.04.10-The Exotic World of Prometheus.

(Credit: NASA/ESA/Cassini).

(Credit: NASA/ESA/Cassini).

 The tiny shepherd world of Prometheus.

    The moons of Saturn continue to astound. The count now stands at 61, and one by one, NASA’s Cassini orbiter is giving us a close up look at these unique worlds, some for the first time. Last year, Cassini passed within 36,000 miles of Prometheus just the day after Christmas. Discovered by Voyager 1 in 1980, this shepherd moon dips within the F-ring once every 15 hour orbit. This fact is apparent as the oblong cratered surface on the 74 mile long moon is coated with a fine layer of dust, giving it a smooth appearance. The constant “plowing” of these moons through Saturn’s rings cause the grooves that we see, and also confines the F-ring. These images are especially satisfying to Carolyn Porco, lead scientist of the Cassini research team who was also on hand for the tiny moon’s initial discovery by Voyager in 1980. It’s likely that we won’t get another look at this bizarre shepherd moon for some years to come!

14.04.10: Milankovitch Cycles…On Titan?

 

(Credit: NASA/JPL/University of Arizona).

(Credit: NASA/JPL/University of Arizona).

An amazing sight; sunlight reflected off the Kraken Mare caught by Cassini! 

   NASA’s Cassini spacecraft has revealed an elusive mystery on the surface of Titan; namely, why does the northern hemisphere of the large moon contain numerous lake basins, while in the south they’re relatively scarce? Now, scientists at Caltech working with JPL think they may have an answer. These lakes show up as bright (empty) and dark (filled) patches as the Cassini spacecraft pings them with its Synthetic Aperture Radar (SAR). Of course, on Titan, the hydrologic chemical of choice is liquid ethane and methane, and it is thought that some transport mechanism results in a net flow imbalance between the two hemispheres. Seasons on Titan last roughly 15 years as it dances around Saturn in its 29.5 year orbit about the Sun. But simple seasonal drainage of about a meter per year couldn’t empty the 100 meter-plus deep basins in a single season. This also doesn’t account for the overall disparity in number of basins seen, both filled and unfilled. Instead, scientists point towards the eccentricity of Saturn’s orbit as the possible cause. Saturn’s eccentricity is 0.055, or a little over 5% deviation from a perfect circle. This would make for periodic inequalities in the seasons, much like what occurs on Earth. For example, the perihelion of Earth actually occurs in northern hemisphere winter, somewhat ameliorating the severity of the seasons. But the variation of eccentricity coupled with the obliquity of the planetary spin axis and the precession of the equinoxes can vary over geologic time scales, causing variations in the climate. This is known as the Milankovitch cycle, and is thought to be a major contributing factor to the onset of Ice Ages. On Titan, a similar process is thought to occur, resulting in a net imbalance over thousands of years in the methane flow cycles between the two hemispheres. We may now simply be observing Titan during an epoch when seasonal methane pooling favors the northern hemisphere. Whatever the case, Titan is proving to be a fascinating and changing world deserving of further scrutiny.

04.03.10: A Close Flyby of Phobos.

401-20080729-5851-6-na-1b-Phobos-Flyby_H1
Phobos on a pass of Mars Express last July. (Credit: ESA/DLR/FU Berlin/G. Neukum).

  

 The European Space Agencies’ (ESA) Mars Express orbiter completed the closest ever flyby of the misshapen Martian moon, Phobos, but don’t expect to see any mind blowing pictures…yet. Part of a series of 12 flybys, last nights’ pass skimmed to worldlet by 67 km, allowing its feeble gravity to deflect the space probe by a tiny but perceptible amount. This will allow engineers on the ground to get an idea of the internal density and composition of Phobos. But to do so, all instruments must be silent, so scientists can isolate minute oscillations on the probes carrier signal via the Doppler Effect. But take heart; Mars Express will further probe the moon on future passes via its MARIS radar, and will have its cameras switched on during next weeks’ March 7th pass…expect more cool pics soon!

Hailing Phoenix.

This week, engineers at NASA’s Jet Propulsion Laboratory will begin listening for a very special phone call; that of the Phoenix Lander on the northern polar region of Mars. Spring is in the air on the northern hemisphere of Mars, and bets are on as to whether the Lander survived the bleak Martian winter. Already, the outlook isn’t stellar; Phoenix has more than likely been encased in CO2 ice for several months; and don’t forget, the Martian year and seasons are roughly twice as long as here on Earth! Add to the fact the Mars is close to aphelion in its relatively eccentric orbit, and the odds don’t look good.  To phone home, Phoenix will need to recharge its spent batteries to a point where its automated broadcasting can kick in; the solar angle is currently about the same as when scientists lost contact last year. If it does start transmitting, Mars Odyssey currently in orbit will be listening. Odyssey passes over the landing site about 10 times a day, and will listen in over the next few months.  The sixth successful landing on the Red Planet and only the third successful soft landing, Phoenix returned some first rate science, and gave us concrete evidence of water ice lurking just below the Martian soil. Now approaching opposition, Mars is rising low in the east just after dusk; more on that next week! For now, Let’s hope that Phoenix lives up to its namesake and rises from the dead!

18.10.09:It’s…SPACE PORCH!!!

NASA astronauts recently completed the installation of an interstellar deck that’s out of this world. Installed on STS mission -127, the Japanese Exposed Facility, or JEF, isn’t your ordinary lawn deck. This terrace-like attachment to the International Space Station (ISS) will host up to nine experiments at a time and make lengthy space walks to swap out experiments or gather data unnecessary. Installed on July 23rd of this year, the JEF is fully accessible to the Kibo robotic arm and will house experiments that require a complete vacuum or temperatures only found in space. It will also enable the burgeoning ISS to get down to what its highly criticized for; performing real science. JEF is now open for business and already houses four experiments: SEDA-AP, the Space Environment Data Acquisition equipment Attached Payload, designed to gauge radiation in the near Earth environment; MAXI, the Monitor & All-sky X-ray Imager, that will scan the entire sky at X-ray wavelengths and alert astronomers to X-ray bursts within 30 seconds of their detection; SMILES, a monitor for sub-millimeter wave emissions in the high stratosphere; and HREP, an experimental payload of hyper-spectral senors designed to conduct the most comprehensive survey of Earth’s ionosphere in years and described as “Landsat on steroids”. Another experiment, dubbed CALET, the CALorimetric Electron Telescope, will study high energy cosmic rays and is slated for installation by 2012. Clearly the JEF is not your suburban weekend warrior “project porch”…we here at Astroguyz are curious; did they have to host a kegger at the ISS to get the shuttle to stop by?

14.10.09: The Earth-Moon System as viewed by HiRISE.

The image above floated through our tweet-o-sphere yesterday, thus prompting today’s news post. HiRISE, NASA’s High Resolution Imaging Science Experiment aboard the Mars Reconnaissance Orbiter(MRO) is the spacecraft that you’re probably not following, but should be. In orbit about the Red Planet since early 2006, its been transmitting some pretty mind blowing images, all definitely worth a daily peek! Housing a 0.5 meter reflecting telescope which would be the envy of any backyard astronomer, its the first true “spy satellite” quality orbiter that we’ve fielded about Mars. Able to resolve targets about 0.3 meters across, some of the highlights have included stunning views of the polar caps and dunes, snapshots of the Opportunity and Spirit landing sites, and even catching the Phoenix Lander in descent! In fact, eagle-eyed desktop amateurs may even prove successful it divining the fate of the many (more than half!) errant Mars-bound landers over the years. But as is often the case with space exploration, we travel millions of miles to find…ourselves. Some of the most memorable images are actually those of the Earth, whether its “Earth-rise” aboard Apollo 8 or the “Pale Blue Dot” as viewed from Voyager 1, images such as these and the HiRISE pic above of our tiny home remind us how special our place is. Snapped back in 2007, it shows us that the Earth is not only a pretty, but dynamic place were things are happening. Mars is tiny and cratered, and through a backyard telescope, generally yields little detail. Venus, although dazzling, is perpetually shrouded in sulfurous cloud. Not so with the Earth. Cloud cover changes, the surface shows a variation in sea, land, and seasonal growth, and at night, an experienced telescopic eye might just pick out the lights of cities, evidence of human activity. Views like this always remind me of Arthur C. Clarke’s little known but classic short story Report on Planet Three, where Martian scientists argue that life couldn’t exist on Earth! Clarke wryly points out that life elsewhere may not be remotely Earth-like. I personally can’t wait to spread my telescope tripod legs out under a night under Martian skies; and without a doubt, the slender crescent Earth-Moon duo will be my first astronomical target!