Astronomy.com blog : Daniel Pendick, spacecraft

August 2009 web extras for magazine subscribers

Karri Ferron — Tue, 23 Jun 2009 21:30:00 GMT

Now that the August 2009 issue of Astronomy is in the mail or already in hand, we’ve updated Astronomy.com with our newest web extras to give subscribers exclusive complementary information to this special issue about our return to the Moon.

Take a sneak peek inside the August 2009 Astronomy magazine.

If you subscribe to Astronomy, make sure you’re registered with Astronomy.com so you can access these great extras.

Here are this issue's highlights:

Senior Editor Richard Talcott shares a NASA video animation preview of the Constellation program that will put humans back on lunar soil in “Return to the Moon.”

Associate Editor Daniel Pendick explores the opinions on NASA’s concept of “Moon first, then Mars” in “Should we go to the Moon first?”

Pendick also explains the uncertain effects of long-term exposure to space radiation and low gravity in “What are the health risks of a Mars mission?”

Senior Editor Michael E. Bakich offers an in-depth preview of the LRO and LCROSS missions that jointly launched June 18 in “NASA's next Moon mission.”

Pendick answers the “Ask Astro” question: “How warm does it get on Mars?”

And I’ve included a few more Q&As with Frank Shu and Joan Najita in “Astro Confidential: Extending the conversations.”

Of course, we’ve also posted “Bob Berman’s Strange Universe,” “Glenn Chaple’s Observing Basics,” “Stephen James O’Meara’s Secret Sky,” and “David Levy’s Evening Stars.” There are also August’s “The Sky this Month” and five “Ask Astro” questions.

Related:

Astronomy.com's Lunar Reconnaissance Orbiter mission page

LRO scientist Michael Wyatt blogs for Astronomy

Daniel Pendick — Tue, 16 Jun 2009 19:39:00 GMT

If all goes as planned, the Lunar Reconnaissance Orbiter (LRO) will launch from Cape Canaveral either Thursday or Friday, depending on the launch of space shuttle Endeavour. Brown University professor and LRO researcher Michael Wyatt is at the launch site, and starting today, Wyatt will share his impressions of this historic mission — the opening maneuver in the United States return to the Moon — with all of you. Thanks, Michael!

We'll post Michael's updates to this article in our news section, "Exclusive: Lunar Reconnaissance Orbiter updates from mission scientist."

Your Mars questions, Dr. C answers

Daniel Pendick — Fri, 05 Jun 2009 15:33:00 GMT

The Jet Propulsion Laboratory’s Mars Exploration Program web site has a fun new feature — Ask Dr. C, “your personal Mars expert.” You can type in a simple question — the simpler, the better — and get a pretty good answer. A computer program tries to match your question with an extensive database of responses.

The real Dr. C is Phil Christensen, a planetary scientist at Arizona State University. Christensen is the Principal Investigator for the 2001 Mars Odyssey Thermal Emission Imaging System (THEMIS) instrument, and the Thermal Emission System instrument on Mars Global Surveyor.

I decided to put the virtual Dr. C through a few paces. Here’s the result.

Dr. C: Hello ... it is a great day to learn about Mars! Please feel free to ask me any questions you would like about Mars ... or even about myself.

Pendick: Does NASA really have enough money to replace the shuttle by 2014, or should we just rename the Russian space program "NASA Moscow"?

Dr. C: I am sorry, I am not sure what you are asking. You might want to try rephrasing your question, searching for it on the Internet, or visiting http://mars.jpl.nasa.gov.

Pendick: OK, fine. I’ll stick to Mars questions then. Anti-global-warming bloggers say that because the martian south pole is currently in a warming trend, this means rising global temperatures on Earth are also "natural" and not manmade. Is it just me, Dr. C, or is that the stupidest thing you ever heard?

Dr. C: I am sorry, I am not sure what you are asking. You might want to try rephrasing your question, searching for it on the Internet, or visiting http://mars.jpl.nasa.gov.

Pendick: OK! OK! I’ll throw you a bone. Here’s an easy one. Why is Mars red?

Dr. C: Mars looks red due to a combination of the fact that its surface is comprised of iron-rich minerals that essentially rust (or oxidize) and that the dust made of these minerals is kicked up into the atmosphere, giving the atmosphere a reddish hue. The Martian surface is not all rust-colored, however, because depending on the oxidation process, the minerals can be a range of colors from butterscotch to rust.

Pendick: Nice answer! So, what is the warmest it ever gets on Mars?

Dr. C: Did you mean to ask "What is it like on Mars?" or "What is Mars?"?

Pendick: No, I am asking you how warm it gets on Mars.

Dr. C: If you were asking: How warm is Mars?, the answer is: Sometimes people think Mars is hot because it is red but, due to its distance from the sun, Mars is actually very cold (its average temperature is minus 81 degrees Fahrenheit!). However, the temperature on Mars may reach a high of about 70 degrees Fahrenheit (20 degrees Celsius) at noon, at the equator in the summer.

Pendick: Just one more question for now. Do you know of an aerospace stock that will rise, say, 40 percent over the next 6 months? I need to buy a new telescope.

Dr. C: I am sorry, I am not sure what you are asking. You might want to try rephrasing your question, searching for it on the Internet, or visiting http://mars.jpl.nasa.gov.

WorldWide Telescope adds Mars Reconnaissance Orbiter images

Daniel Pendick — Wed, 25 Mar 2009 21:41:00 GMT

Megacorps are practically lining up for the privilege of disseminating fantastic volumes of astronomical images to you, John and Jane Q. Public.

Recently Google added a “Live from Mars” function to its 3-D visualization of Mars within Google Earth. The feature allows you to see images from the Mars Odyssey spacecraft.

Now Microsoft says it will let you explore images from the Mars Reconnaissance Orbiter (MRO, pictured at right) within its web-based astronomy application, WorldWide Telescope (WWT).

More than 100 terabytes (1 terabyte equals 1 trillion bytes) of NASA data, including images from MRO that has been studying the planet since 2006, will be incorporated into WWT later this year, according to Microsoft. Images from a camera aboard NASA’s Lunar Reconnaissance Orbiter set to launch in May will also be made available.

The inherent coolness of “Live from Mars” is that you can see new images from Odyssey’s THEMIS camera nearly as soon as scientists themselves — within a day or so, usually.

The unprocessed THEMIS images themselves are not exactly works of art. They are detailed, but in grayscale. The instrument that takes them works in infrared.

I am not aware of any plan to post MRO images “live” on WWT. But it would indeed be very cool if they did. MRO’s HiRISE camera takes stunning images.

It would be a win for us astro fans if a little healthy rivalry between Google and Microsoft spurred them to make even more NASA data available for us to explore in a user-friendly way, either in Google Earth or WWT.

Mars in Google Earth works in Windows, Macintosh, and Linux operating systems. The full-feature downloaded version of WWT works only on Windows machines right now. But WWT has recently made available a web-based version with all the major functions, and it runs beautifully on a Mac. No matter what operating system you run, you will be able to use the web version of WWT to look at the new MRO images, once they are available. (Note: To use the web-based WWT, you have to install a small plug-in called Microsoft Silverlight.)

If you are a true Marsaholic like me, you may also appreciate the Mars Express “web cam” that shows images of the Red Planet. It recently came back online after the craft emerged from behind the Sun. Check out the Mars Express Visual Monitoring Camera blog.

Exclusive: Q&A with Europa expert Richard Greenberg

Daniel Pendick — Thu, 19 Feb 2009 21:57:00 GMT

Richard Greenberg, a professor of planetary sciences at the University of Arizona's Lunar and Planetary Laboratory, is an expert in celestial mechanics and carries out NASA-sponsored investigations of solar system evolution and planet formation. He is also author of the current book Unmasking Europa.

After NASA and the European Space Agency chose Jupiter’s moons — including Europa — as the next destination for a major planetary exploration mission, Greenberg answered a few questions about the upcoming missions and his book about Europa, “an active oceanic world that just might be the most likely site for our first encounter with extraterrestrial life.”

Pendick: Are you surprised at all by NASA and ESA’s decision to go to Jupiter’s moons before going to Saturn’s moon Titan?

Greenberg: I think both proposed missions are exciting and both Europa and Titan are fantastic satellites to explore. As far as the competition for the next flagship in line, it is not a surprise that Europa was selected. It has been a top priority since the Galileo mission provided evidence for the global ocean. And the prospect for it being the place where we will most likely first find extraterrestrial life makes it an objective of almost existential significance!

That said, the discoveries about the Saturn system from the Cassini mission have shown us what active and exciting places Enceladus and Titan are. And the Titan Science Definition Team did a great job of developing a model mission that is really imaginative and spectacular.

In many ways the Titan mission is at least as appealing as the Europa one. So it is interesting that NASA did not simply make an either/or decision between the two missions — as was originally expected — but instead they made the announcement a prioritization, which leaves the door open to including the Titan mission as future budgetary and policy issues are addressed.

While I personally love Europa, for all the reasons I describe in my book Unmasking Europa, I am a big fan of the Titan mission as well.

Pendick: If you had to choose a few major points, what would you say the Europa orbiter will most likely tell us — and not tell us? For example, will the mission confirm the existence of Europa’s global ocean and perhaps how deep it is, but NOT tell us whether anything lives in it?

Greenberg: I personally believe that we already confirmed the existence of the ocean with our work on explaining the cycloidal crack patterns in terms of tidal stress and also with the Galileo magnetometer evidence. The new mission will have a laser altimeter to measure the height of Europa’s tides, and the radio tracking will also measure the gravitational effect of the tides. That information about the tides will further confirm the existence of the ocean. Contrary to some reports I have read, though, I do not believe the radio and altimeter information about the tides will tell us how thick the ice is.

There will also be an ice-penetrating radar that will tell us a lot — I hope — about the structure within the icy crust, which will help us understand the dynamics of the crust and the transport of materials between the ocean and the surface, which is critical for life, as I emphasize in my book.

The spacecraft will have a narrow-angle camera for super high-resolution imaging of Europa’s surface, in addition to wider-angle cameras. I hope the folks who plan the imaging will favor the narrow-angle camera, so we can really get a handle on the active processes that must be continually resurfacing Europa.

Other remote sensing will include an infrared spectrometer to identify the critical substances mixed in with the ice and a thermal instrument to map the heat distribution.

Naturally, if I were the king of NASA, I would order a lander to plop down selectively on a site where ocean material has recently been exposed. I could imagine finding marine organisms without needing to drill down very deep. But that is evidently something saved for a distant future mission.

Pendick: Too bad we all have to wait until 2026 to find out if you are right about Europa! But that leaves 17 years for us to read all about it in your book, Unmasking Europa. Tell us why you wrote the book and what we can learn about Europa by reading it.

Greenberg: I wanted to write this book because I knew several great parallel stories that would be fun to tell. The first was a fantastic science story about a satellite with an ocean containing twice the liquid water of all Earth’s oceans and an icy crust that is continually renewed by tectonic and thermal processing that links the ocean to the surface. Most of this information was in fragmentary form in the scientific literature, so I wanted to integrate it and make it accessible to any thoughtful reader.

Also, there had been a great deal of speculation about life perhaps being possible at imaginary volcanic vents on the ocean’s floor, but no one else was talking or writing about how the openings through the ice could really enhance the prospects for life in the ocean and that the biosphere of Europa, if any, would well extend right up to the surface.

There are also policy implications that had been under-appreciated. We may not need to drill down through the ice to reach life. It could lie very near the surface. That is the good news for exploration. The bad news, of course, is that we need to be very careful to avoid contaminating such a vulnerable place.

I also wanted to tell the story of how my own interdisciplinary research group had come to assemble this picture of a permeable ice layer by interpreting images of the surface in terms of our understanding of tides, and in the context of the wonderful scientific contributions of many other colleagues from other places.

And finally I wanted to tell the story of what I learned about the place of science in the framework of a large space mission. I wanted people to get an idea of how science really works. Like any creative human endeavor, it has its glorious aspects and its ugly ones. But it was always interesting and often hilarious. I just had to tell about it. These several story lines were interwoven and seemed to me inseparable, so that is how I wrote the book.

Europa vs. Titan: Which will NASA explore in its next flagship mission?

Daniel Pendick — Wed, 11 Feb 2009 18:11:00 GMT

“There is an ocean beneath the icy crust of Jupiter’s moon Europa [pictured at right]. Strange creatures could be swimming in these alien waters, but so far no missions have been sent there to investigate this possibility.”

So begins, "Hoping for Europa," an article by Astrobiology magazine Editor Leslie Mullen. Squids from outer space — who could resist?

Or will it be a balloon ride over the windblown surface of a hydrocarbon lake on Titan [pictured at lower left]?

“A hot air balloon drifts gently in the breeze, gliding over mountain ranges and vast lakes,” Mullen writes in another article, "Titan Triple Threat."

“Thick clouds extend over the entire horizon, threatening rain. The meager light that filters through illuminates one side of the balloon, making it look like a giant question mark in the sky.”

Later this week, NASA is expected to announce which moon of the outer solar system will be the target of a future $2 billion-plus “flagship mission.” It would likely be carried out as a partnership with the European Space Agency, along the lines of the Cassini-Huygens mission to Saturn.

The prospect of studying an alien ocean beckons. So does getting a closer look at Titan’s geologically active surface. The consensus seems to be that we are much more likely to find alien life on Europa than in the methane/ethane lakes of Titan. But who knows?

Either way, be patient. These missions would not launch before 2020 or so. If Titan gets the nod, expect a travel time of 9 years.

As soon as NASA decides, we’ll get back to you with some expert commentary.

Bail to the chief

Daniel Pendick — Thu, 22 Jan 2009 22:13:00 GMT

With all the talk of financial bailouts in these, shall we say, fiscally distressed times, I can’t be the only one wondering how NASA will fare in the new administration.

When I saw the photo of the lunar rover rolling past the Presidential bandstand in the inaugural parade, I couldn’t help but wonder if the driver was sitting there with his fingers crossed, fervently mumbling, “Oh, please please please keep those NASA greenbacks flowing, Mr. President.”

It seems unlikely President Obama will pull the plug on the Constellation Program, which is now designing and building the post-space shuttle generation of launch vehicles. Being able to send our own people into space without hitchhiking rides with the Russians seems essential.

But what about the plan — former President Bush’s plan — to return to the Moon by 2020? We’re talking some serious money, here — counted in increments of hundreds of billions.

I personally wouldn’t even venture a guess. But going to the Moon could prove an easy target in a time when millions of jobs are evaporating before our collective eyes.

Not to be a pessimist, but consider what it could mean that Obama’s science advisor is John P. Holdren, a professor of environmental policy at Harvard. He might perhaps think that climate change research and mitigation — not putting more American boots on the lunar maria — should be the priority.

Of course, budgets aren't as simple as robbing from NASA Peter to pay environmental Paul. NASA gets a single pot of money, and from that must come the money for human spaceflight as well as climate-change research, not to mention flinging rovers and orbiters at the planets.

New details on Columbia crew’s final moments

Daniel Pendick — Wed, 31 Dec 2008 16:59:00 GMT

A NASA panel has just released a detailed report revealing the last moments of the space shuttle Columbia and its seven-member crew, lost February 1, 2003, on reentry. You can download the 400-page report, “Columbia Crew Survival Investigation Report."

The cause of the accident has been clear since soon after the disaster: A piece of insulating foam struck the leading edge of one of the orbiter’s wings. During reentry, searing hot gases entered the breach, ultimately causing the breakup of the craft at an altitude of 200,000 feet. [report]

One thing is clear from the report: Except for preventing the wing damage in the first place, nothing could have saved the crew.

The crew — Michael Anderson, David Brown, Kalpana Chawla, Laurel Clark, Rick Husband, William McCool, and Ilan Ramon — knew for about 40 seconds that they had lost control of the orbiter. The report says they apparently tried everything they could to regain control.

Their efforts ceased when the crew cabin rapidly depressurized, causing the astronauts to lose consciousness. “The Columbia depressurization event occurred so rapidly that the crew members were incapacitated within seconds, before they could configure the suit for full protection from loss of cabin pressure,” according to the report.

The depressurization was the immediate cause of death. But in this particular case, sealed suits would not have saved the astronauts; They were at too high an altitude. But in a depressurization under different circumstances, it might.

Also, the chest harnesses did not lock when the cabin started to experience abnormal motions. Because the crew members were restrained only at the waist, their torsos would have been whipped around as the cabin separated from the orbiter and spun out of control. Again, in the Columbia accident, the harnesses offered no hope of survival, but in other scenarios they might prevent injuries.

The report’s recommendations suggest that NASA reevaluate crew training, emergency procedures, pressure suits, and onboard safety systems in light of the Columbia accident. There is still time to incorporate the tough lessons learned from this tragedy and possibly prevent future mishaps after NASA rolls out the Ares/Orion launch system that will replace the shuttle after its retirement in 2010.

Enceladus ice tectonics: Cassini’s latest mind-blowing image of another world

Daniel Pendick — Wed, 17 Dec 2008 19:36:00 GMT

Many phases of the Moon ago — more than 200 — I came under the spell of earth science and wrote a lot about it for a number of years. This week, some of that ancient knowledge came back to visit as I gazed at a fantastic 28-image mosaic of Saturn’s moon Enceladus.

You may see crusty cracked ice; I see the outlines of ice continents.

At the American Geophysicial Union meeting in San Francisco this week, the halls are abuzz with talk of plate tectonics on Enceladus.

Using Cassini-based digital maps of the south polar region of Enceladus, Paul Helfenstein of Cornell University in Ithaca, New York, reconstructed a possible history of the famous “tiger stripe” features by working backward in time and progressively snipping away older and older sections of the map. Each time he found that the remaining sections fit together like puzzle pieces. Bottom line: Giant fragments of Enceldus’ crust ARE MOVING.

In the 20th century, earth scientists found evidence for plate tectonics on Earth in part by reassembling puzzle pieces of Earth’s crust delineated by cracks in the seafloor called plate boundaries.

At some boundaries, tectonic plates scrape past each other; at other boundaries, plates nose under a neighbor or crash straight into each other, raising great mountain ranges like the Himalayas.

The same process is happening on Enceladus. This implies that energy is flowing somewhere underneath all that ice — probably heat convection similar to the swirling flow ina boiling pot.

Exobiologists think that where some sort of “energy gradient” exists — a difference between warm and cool, for example — life can develop. In the 1970s, biologists stumbled on diverse ecosystems thriving at plate tectonic boundaries on the seafloor. Hot hydrothermal water and elements like sulfur were all they needed to live in the inky darkness.

Oceans of water lie beneath the crust of Encaladus. The region near its famous geysers is warmer than its surroundings — an energy gradient if ever there was one. And the geyser jets contain organic molecules.

If we could drill beneath the icy continents of Enceladus — like the pilots of the deep-sea submersible Alvin visiting hydrothermal vent ecosystems — what might we find there?

Picture thick mats of bacteria coating cracks and crevices in the hydrothermal systems in Enceldaus crust.

It’s the stuff of science fiction, but could come true in our lifetimes.

One small step for ... Ooops!

Daniel Pendick — Wed, 19 Nov 2008 14:47:00 GMT

I just received a media advisory from James Oberg, a contributor to Astronomy and noted space historian. And I learned something new — something historic. Something I’m a little embarrassed I didn’t know. It appears that many video producers continue to misrepresent Neil Armstrong’s comments the day he stepped onto the Moon (that's Apollo 11 astronaut Buzz Aldrin pictured at right). Oberg explains it best:

The National Geographic Channel is running “Expedition Week” with several space-related stories, including the must-see excellent Five Years on Mars, about the rovers Spirit and Opportunity. It also has a special on Moon exploration, Direct from the Moon, which contains excellent new material from Japanese Moon exploration.
Unfortunately, that Moon program also repeats the single GREATEST bogus piece of Apollo program mis-history — a point that must be made and made over again as we move into the 40th anniversary of the Apollo Moon missions in the months ahead. Don't make this “classic” mistake.
I wrote about the flaw some years ago — for example, in the Wall Street Journal on the 35th anniversary.
Here's what I wrote then, still valid — and still snaring careless producers:
To compress events, Neil Armstrong's comments about making "One small step" have often been matched with video of him dropping down from the Lunar Module ladder. Actually, he landed on one of the vehicle's footpads, made several comments, jumped back up on the ladder to make sure he could, jumped down a second time, discussed his impressions of his surroundings, and only after that did he make the "small step" onto the moondust. So the rearranged video completely misrepresents what he meant by "one small step".
In the National Geographic production, Armstrong is seen on the ladder, and his comment, "I'm going to step off the LM," is voiced over. He then descends straight down, holding the ladder sides, and his voice is heard intoning the “one small step” sequence. This is totally bogus — although even some NASA video productions in the 1990s had the same error.
My 1994 story concludes:
When TV programs pose as ‘true history’ and are presented as documentaries, a higher standard of authenticity should be required. The Apollo-11 anniversary programs showed again that such standards are not universally met. Some programs, such as Discovery's One Giant Leap, were strikingly accurate, showing signs that some producers took the extra trouble to "get it right,” and knew how to do so. But the widespread misrepresentations in other shows are more reminders that people should seek truth where it can be found, and the TV screen, with its need for visual excitement and compressed action, is not an environment always conducive to historical accuracy.

Thanks, Jim! In months to come, we'll be reporting on the true history of Apollo, and be wary of the mythologized versions that have crept into our reportage and even our memories.