Sometimes you can do science by watching patiently, and sometimes you’ve just got to get your hands dirty with an experiment or two. These two methods have their advantages and disadvantages for revealing Nature’s secrets. Let’s talk about how and why scientists choose which path to go down.
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The first photo of the lunar far side taken by the Soviet (Russian) spacecraft Luna 3 on Oct. 7, 1959. The right three-quarters of the disk is the far side. A = Mare Moscoviense, B = Tsiolkovsky Crater with central peak, C = Mare Smythii (on the near side-far side border) and D = Mare Crisium (near side). This is the wide-angle view. Credit: Roscosmos
For millennia, human eyes have seen only one face of the moon. Put a dude from the Iron Age in a time machine and whisk him to 2013 and he’d see the same pattern of light lunar highlands punctuated by dark grey spots you see. Night after night after night.
Telephoto view of the far side with Mare Smythii (Sea of Smyth) at left and bright crater Giordano Bruno at center. Credit: Roscosmos
That all changed 54 years ago today when the Soviet Union’s Luna 3 probe opened its camera shutter and snapped the first pictures of the lunar far side. Though blurry and banded with electronic noise, everyone who saw them sat up in surprise. The backside barely resembled the front. It lacked in the familiar lunar maria, the dark spots that we instinctively patch together to form the face of the “man in the moon”.
Telephoto image of Mare Moscoviense is at upper right with Tsiolkovsky and its bright central peak at lower right. You can begin to see vague outlines of many more craters in this picture. Click for more historic photos. Credit: Roscosmos
Only two dark ovals were seen, Mare Moscoviense (Sea of Moscow) and the lava-filled floor of the crater Tsiolkovsky, named for Konstantin Tsiolkovksy, the Russian rocket pioneer. The rest, which looks like dried paste, is jammed with craters and related the near side’s light-toned, cratered highlands. Both are remnants of the original lunar crust that solidified as the moon cooled after formation.
The dramatic difference between near side and far side shows up in this much more recent global map of the map made by Clementine Mission in 1994. The map is centered on the near side with its many lunar “seas” or maria. The far side trails off to the left and right of center. Mare Moscoviense is at upper right. Credit: NASA
Darker areas or “seas” are more recent basaltic lavas that welled up to fill huge impact scars left by colliding asteroids. They contain iron-rich minerals from deep beneath the crust which make them less reflective, hence darker in comparison to the highlands.
Tidal locking results in the moon rotating about its axis in about the same time it takes to orbit the Earth (left side). If the Moon didn’t spin at all, then it would alternately show its near and far sides to the Earth while moving around our planet in orbit, as shown in the figure on the right. Credit: Wikipedia
The moon hides its back or far side through a neat trick – it rotates at the same rate as it revolves around the Earth. Normally, rotation would bring new features into view, but every little bit it turns, it moves an equal amount along its orbit, hiding what would otherwise be exposed. It’s called synchronous rotation or tidal locking. Most of the larger moons in the solar system are tidally locked to their planets. Jupiter’s four biggest and brightest moons are a great example.
Luna 3 probe sent to the moon by the then Soviet Union. It held two cameras and its own film processing lab. Credit: NASA
Equipped with both wide angle (200 mm) and telephoto (500 mm) lenses, Luna 3 took 29 pictures covering about 70 percent of the far side during its loop around the moon. The first picture was shot from 39,500 miles away (63,500 km), the last taken 40 minutes later from 41,445 miles (66,700 km) distant. After the photo session was done, the probe passed over the moon’s north pole and headed back toward Earth.
Temperature and radiation-resistant film used for the photos was automatically moved to an onboard processor where it was developed, fixed and dried. A cathode ray tube then shot a beam of light through the film and onto a photoelectric multiplier, a light-sensitive device that converted the different gradations of tone into electric signals which were then transmitted to Earth. Almost sounds like a fire brigade, but hey it worked!
High resolution photo map of the moon’s far side imaged by NASA’s Lunar Reconnaissance Orbiter. Mare Moscoviense lies at upper left and Tsiolkovsky at lower left. Click for a hi res image. Credit: NASA
So what’s the reason for the moon’s split personality? We know the far side crust is 50 miles (80 km) thick versus 37 miles (60 km) for the near side. A thicker far side crust may have prevented magma from reaching and flooding the surface as they did on the near side. Heat released by the decay of radioactive elements also may play a role. NASA’s Lunar Prospector probe found more on the near side, where they may have encouraged the formation of hot magmas that eventually found their way to the surface.
What caused the fascinating asymmetry is unknown, but it may have to do with the slowing of the moon’s rotation into its present tidally-locked state under the heavy hand of Earth’s dominating gravitational influence.
A global view of Mercury, as seen by MESSENGER. Credit: NASA
Three to two. That’s the ratio of the time it takes Mercury to go around the sun (88 days) in relation to its rotation (58 days). This is likely due to the influence of the Sun’s immense gravity on the planet. A new study confirms that finding, while stating something even more interesting: other star systems could see the same type of resonance.
Hundreds of confirmed exoplanets have been found so far, many of them in very tight configurations, the authors said. “Mercury-like states should be common among the hundreds of discovered and confirmed exoplanets, including potentially habitable super-Earths orbiting M-dwarf [red dwarf] stars,” they added. “The results of this investigation provide additional insight into the possibilities of known exoplanets to support extraterrestrial life.”
Habitability, of course, depends on many metrics. What kind of star is in the system, and how stable is it? How far away are the planets from the star? What is the atmosphere of the planet like? And as this study points out, what about if one side of the planet is tidally locked to its star and spends most or all of its time with one side facing the starshine?
Additionally, the study came up with an explanation as to why Mercury remains in a 3:2 orbit in opposition to, say, the Moon, which always has one side facing the Earth. The study took into account factors such as internal friction and a tidal “bulge” that makes Mercury appear slightly misshapen (and which could slow it down even further.) Basically, it has to do with Mercury’s early history.
From Orbit, Looking toward Mercury’s Horizon. Credit: NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington
“Among the implications of the released study are, to name a few, a fast tidal spin-down, a relatively cold (i.e., not fully molten) state of the planet at the early stages of its life, and a possibility that the internal segregation and formation of the massive liquid core happened after Mercury’s capture into the resonance,” the press release added.
The results were presented today (Oct. 7) at the American Astronomical Society department of planetary sciences meeting held in Denver. A press release did not make clear if the study has been submitted for peer review or published.
Artist’s impression of the deep blue planet HD 189733b, based on observations from the Hubble Space Telescope. Credit: NASA/ESA.
Finding Earth 2.0, in the words of noted SETI researcher Jill Tarter, is something a lot of exoplanet searchers are hoping for one day. They’re trying not to narrow down their search to Sun-like stars, but also examine stars that are smaller, like red dwarfs.
A new study, however, cautions that the X-ray environment of these dwarfs may give us false positives. They looked at Earth-mass planets in the neighborhood of four stars, such as GJ 667 (which has three planets that could be habitable), and concluded it’s possible for oxygen to reside in these planets even in the absence of life.
The work builds on a published paper in the Astrophysical Journal that argues that GJ 876, studied by the Hubble Space Telescope, could allow a hypothetical planet to have plenty of oxygen in its atmosphere, even without the presence of life.
This artist’s conception shows the newly discovered super-Earth GJ 1214b, which orbits a red dwarf star 40 light-years from our Earth. Credit: Credit: David A. Aguilar, CfA
The researchers themselves, however, caution that the results are preliminary and there is a lot more to study before coming to a definitive conclusion.
For example: “The effects of stellar flares on the atmosphere of the hypothetical Earth-like planet around GJ 876 have not been considered in this work,” stated Kevin France, who is with the University of Colorado at Boulder and also a co-author.
“At this point, we do not have a sufficient understanding of the amplitude and frequency of such flares on older, low-mass exoplanet host stars to make predictions about their impact on the production of biomarker signatures.”
The report was presented at the American Astronomical Society division for planetary sciences meeting in Denver today (Oct. 7). It was not immediately clear from a press release if the newer study has been submitted for peer review.
"Cavenauts" exploring an underground lake. Credit: ESA/V. Crobu
A few weeks ago, a bunch of astronauts went underground in Italy in the name of science and better finessing the techniques of running a space mission. A movie-style “preview” of their work plays in the video above.
You can see how jazzed the astronauts are about the mission. “It was like being on Mars,” one says. Another says this is inspiration to explore the solar system, because then you get to possibly see beautiful things such as what is right in front of them.
Another wonderful Virtual Star Party, this time with 6 astronomers broadcasting their view of the night sky live. We had amazing views of Saturn, the Ring Nebula, M27, and M17 the Swan Nebula (also known as the Lobster or Horseshoe Nebula). We also caught great views of NGC-896, NGC-869, and the M56 Cluster. Then we got some beautiful views of the Veil Nebula and discussed the benefits of image-stabilized binoculars.
This was also the first time were joined by Scott Ferguson, who delighted us with his dark sky views from the west coast of Florida. His views of the Pelican Nebula (NGC-6996) were gorgeous and unique. Continue reading “Virtual Star Party – October 6, 2013”
Photo taken by ESA astronaut Luca Parmitano on Sept. 5, 2013 (ESA/NASA)
Italian astronaut Luca Parmitano shares a lot of fantastic photos taken from his privileged position 260 miles up aboard the Space Station, orbiting the planet 16 times a day. This is his latest, a stunning view of nighttime city lights spread out beneath a glowing dome of ghostly airglow and shimmering aurorae, with a backdrop of brightly shining stars. The dark silhouette of a solar array is in the foreground at right.
And in case you were wondering, yes, astronauts certainly can see stars while in space. A lot of them, in fact. (Except up there, they don’t twinkle… but they’re no less beautiful!)
“Every time we look into the sky and we admire the same stars, we share the same experience with all those who still know how to dream.”
– Luca Parmitano
Luca Parmitano is the first of ESA’s new generation of astronauts to fly into space. The current mission, Volare, is ESA’s fifth long-duration Space Station mission. During his six-month-long stay aboard the ISS, Luca has been conducting research for ESA and international partners as well as taken many photographs of our planet, sharing them on Twitter, Flickr, and the Volare mission blog.
NASA’s LADEE lunar orbiter will firing its main engine on Oct. 6 to enter lunar orbit in the midst of the US government shutdown. Credit: NASA
NASA’s LADEE lunar orbiter will fire its main engine on Oct. 6 to enter lunar orbit in the midst of the US government shutdown. Credit: NASA
See the orbit insertion animation below[/caption]
Update Oct 6: LADEE fired its main engine this morning (Oct. 6) at 6:57 a.m. EDT and successfully achieved lunar orbit. Headline/story revised.
NASA’s trailblazing LADEE lunar spacecraft is set to ignite its main engine and enter lunar orbit on Sunday morning, Oct. 6 – if all goes well – following the spectacular Sept. 6 night launch from NASA’s Virginia spaceport.
And in a happenstance no one could have foreseen, the critical engine firing comes smack in the midst of the political chaos reigning in Washington D.C. that has shut down the US government, furloughed 97% of NASA’s employees, and temporarily threatened the upcoming launch of NASA’s next mission to Mars – the MAVEN orbiter.
But there will be virtually a complete news blackout and little public information released due to the legal requirements of the shutdown.
NASA websites, which are amongst the most heavily trafficked, as well as NASA TV have been shuttered during the shutdown and the press office is likewise furloughed.
So it was do or die for LADEE with the four minute long braking thruster firing set to start on Oct. 6 at 6:57 a.m. EDT (10:57 UTC), so that the couch sized spacecraft is captured by the Moon’s gravity.
Fortunately, LADEE was deemed “essential” and a small team of engineers is working right now at mission control at NASA’s Ames Research Center in California.
If the had burn failed, LADEE will swing by the moon with no hope of returning. And this is being accomplished with a skeleton crew thanks to the government shutdown.
Here’s a video animation of orbital capture at the moon:
Video caption: This video shows the LADEE lunar orbit capture scheduled to take place at 10:57 UTC on 6 Oct. 2013. The main view is an Earth centered perspective showing the effect of the Moon’s gravity on the orbit and then how a Lunar orbit looks from the Earth. The inset view shows the same trajectory from the perspective of the Moon.
Dubbed LOI-1 (Lunar Orbit Insertion burn 1),it is designed to begin with LADEE’s arrival at the Moon after three and a half orbits of the Earth. It will change the spacecrafts velocity by 329.8 meters/sec.
LOI-1 is the first of three main engine maneuvers and will place LADEE into a 24 hour retrograde orbit, with a periselene altitude of 590 km (369 mi).
LOI-2 follows on Oct. 9 to place LADEE into a 4 hour orbit with a 250 km (156 mi) periselene altitude.
Finally LOI-3 on Oct. 12 places LADEE into a roughly circular 250 km (156 mi) orbit that initiates a 30 day commissioning phase as well as experiments using the on-board Lunar Laser Communications Experiment (LLCD) before the start of the missions science phase.
LADEE thundered to space atop the maiden launch of the five stage Minotaur V rocket on Sept. 6, blazing a spectacular trail to orbit from a beachside launch pad at NASA’s Wallops Flight Facility in Virginia.
This magnificent view of NASA’s LADEE lunar orbiter launched on Friday night Sept 6, on the maiden flight of the Minotaur V rocket from Virginia was captured by space photographer Ben Cooper perched atop Rockefeller Center in New York City. Credit: Ben Cooper/Launchphotography.com
The blastoff was easily visible to tens of millions of thrilled spectators up and down the eastern seaboard stretching from Maine to the Carolinas as a result of crystal clear skies and the night time liftoff.
The LADEE liftoff at 11:27 p.m. EDT marked the first space probe of any kind ever launched beyond Earth orbit from NASA Wallops, as well as being the first planetary science mission ever launched from Wallops.
Launch of NASA’s LADEE lunar orbiter on Friday night Sept. 6, at 11:27 p.m. EDT on the maiden flight of the Minotaur V rocket from NASA Wallops, Virginia, viewing site 2 miles away. Antares rocket launch pad at left. Credit: Ken Kremer/kenkremer.com
Eventually the spacecraft will fly in a very low equatorial science orbit of about 50 kilometers (31 mi) altitude above the moon that will require considerable fuel to maintain. The science mission duration is approximately 100 days, limited by the amount of maneuvering fuel.
The 844 pound (383 kg) robot explorer was assembled at NASA’s Ames Research Center, Moffett Field, Calif., and is a cooperative project with NASA Goddard Spaceflight Center in Maryland.
It is equipped with a trio of science instruments whose purpose is to collect data that will inform scientists in unprecedented detail about the ultra thin lunar atmosphere, environmental influences on lunar dust and conditions near the surface.
The goal of the $280 Million mission is to gain a thorough understanding of long-standing unknowns about the tenuous atmosphere, dust and surface interactions that will help scientists understand other planetary bodies as well.
The probe is built on a revolutionary ‘modular common spacecraft bus’, or body, that could dramatically cut the cost of exploring space and also be utilized on space probes to explore a wide variety of inviting targets in the solar system.
“LADEE is the first in a new class of interplanetary exploration missions,” NASA Ames Director Pete Worden told Universe Today in an interview. “It will study the pristine moon to study significant questions.”
“This is probably our last best chance to study the pristine Moon before there is a lot of human activity there changing things.”
The Very Large Array, one of the world's premier astronomical radio observatories, consists of 27 radio antennas in a Y-shaped configuration 50 miles west of Socorro, New Mexico. Each antenna is 82 feet (25 m) in diameter. The data from the antennas is combined electronically to give the resolution of an antenna 22 miles (36 km) across. Image courtesy of NRAO/AUI and NRAO
While some of you will no doubt be heading to the theaters to see the new release of “Gravity,” for those that want to stay in for the weekend, here’s the perfect short film. The National Radio Astronomy Observatory (NRAO) has released a new 24-minute film about the recently renovated Karl G. Jansky Very Large Array (VLA) radio telescope. The film is narrated by Academy Award-winning actress Jodie Foster, star of the 1997 Warner Brothers film, “Contact,” which was filmed in part at the VLA.
“In ‘Contact,’ I played the role of an astronomer using the VLA,” Foster said. “In narrating this new film for the VLA Visitor Center, I have the privilege of introducing tomorrow’s scientists, technicians, and engineers to the amazing complexities of this great telescope, and to the wonders of the universe that it reveals.”
Titled “Beyond the Visible,” the film tells the behind-the-scenes story of the operation and scientific achievements of the VLA, which has been at the forefront of astrophysical research since its dedication in 1980. Spectacular ground and aerial footage of the iconic radio telescope is augmented by first-person interviews with staffers who keep the telescope working and scientists who use it to discover exciting new facts about the universe. The film also depicts many of the technical tasks needed to keep the array functioning at the forefront of science.
“Since the last film for the Visitor Center was produced in 2002, we’ve completed a massive technological upgrade that turned the VLA into a completely new and vastly more powerful tool for cutting-edge science,” said Dale Frail, NRAO’s Director for New Mexico Operations. “It was time to update the story we tell our visitors,” he added.
The film replaces an earlier video that ran at the VLA Visitor Center auditorium, which is visited by some 20,000 people annually. You can’t currently go to the Visitor Center to see the new film at the moment, however, because of the US federal government shutdown. So, watch it here. Hopefully the shutdown will be resolved soon so that people can resume their visits to the VLA.
Virgin Galactic's WhiteKnightTwo and SpaceShipTwo. Think you could fly them? Credit: Virgin Galactic.
Call it Space Survivor. Thirteen years after that now-classic desert island nightmare premiered on NBC, the executive producer behind Survivor is planning to host another reality competition that will land the winner a rocket trip to space.
We don’t know yet what feats of strength, endurance, intelligence or teamwork (or is that backstabbing?) will be needed to score a trip with Virgin Galactic. A press release simply promises a “groundbreaking, elimination competition series where everyday people compete for the ultimate prize”, but we sure hope a lot of the individual contests are space-related.
“For the past 10 years I have relentlessly pursued my dream of using a TV show to give an everyday person the chance to experience the black sky of space and look down upon mother Earth,” stated executive producer Mark Burnett, who heads One Three Media. Burnett seems to have chosen the Richard Branson-backed SpaceShipTwo (now doing powered flight tests) as the best chance of getting competitors into space in the near future.
Sir Richard Branson hugs designer Burt Rutan as they are surrounded by employees of Virgin Galactic, The SpaceShip Company and Scaled Composites watch as Virgin Galactic’s SpaceShip2 streaks across the sky under rocket power, its first ever since the program began in 2005. Burt’s wife Tonya Rutan is at right taking their photo. The spacecraft was dropped from its “mothership”, WhiteKnight2 over the Mojave, CA area, April 29, 2013 at high altitude before firing its hybrid power motor. Virgin Galactic hopes to become the first commercial space venture to bring multiple passengers into space on a regular basis.
“Last year, I spent time in New Mexico at the state-of-the-art facility and last week [I] spent time in the Mojave desert with Sir Richard and his impressive team. We got to see the spaceship up close and hear of Sir Richard’s incredible vision of how Virgin Galactic is the future of private space travel. I am thrilled to be part of a series that will give the everyday person a chance to see space, and that NBC has come on board too so that viewers at home will have a first-class seat.”
Virgin says its first spaceflight with SpaceShipTwo will be in 2014, and soon after it will open the manifest to the more than 600 folks who have purchased tickets.
As for when we’ll expect to see Space Race hit the airwaves, let’s just caution that this is just an agreement so far and nothing firm has been decided.
Recall that in 2000, Burnett announced another deal with NBC to host a space reality show (Destination Mir), with the winner visiting the Russian space station Mir. That idea fell apart when the cash-strapped Russian Federal Space Agency elected to deorbit the aging station in 2001 and focus its resources on the International Space Station.
Burnett subsequently proposed another show that would have brought ‘N Sync guitarist Lance Bass to the International Space Station, but that idea never got off the ground.
