Artist's impression (not to scale) of the Rosetta orbiter deploying the Philae lander to comet 67P/Churyumov–Gerasimenko. Credit: ESA–C. Carreau/ATG medialab.
What price do you put on scientific discovery? From the way Twitter lit up last week when the Philae spacecraft touched down on Comet 67P/Churyumov–Gerasimenko — it was a top-trending topic for a while — it appears there’s a lot of discussion going on about the Rosetta mission and its value to humanity.
A recent infographic (which you can see below) points out that the Rosetta mission, which included the now-hibernating Philae lander, cost as much as about four Airbus 380 jetliners. Is US$1.75 billion (€1.4 billion) a bargain for letting us explore further into the universe, or could the money have been better-served elsewhere?
This is a question often brought up about the value of space exploration, or what is called “blue-sky” research in general. The first developers of lasers, for example, could not have predicted how consumers would use them millions of times over to watch DVDs and Blu-Rays. Or in a more practical use, how medical lasers are used today for surgeries.
An infographic of Rosetta spacecraft spending. Credit: Scienceogram.org (infographic), ESA/Rosetta/NAVCAM (comet image), ESA (Rosetta graphic), ESA/Airbus (data), Scienceogram.org (other data).
“Like a lot of blue-skies science, it’s very hard to put a value on the mission,” wrote Scienceogram.org, the organization that produced the infographic. “First, there are the immediate spin-offs like engineering know-how; then, the knowledge accrued, which could inform our understanding of our cosmic origins, amongst other things; and finally, the inspirational value of this audacious feat in which we can all share, including the next generation of scientists.”
To put the value of the Rosetta mission in more everyday terms, Scienceogram points out that the comet landing cost (per European citizen and per year between 1996 and 2015) was less than half the ticket price for Interstellar. That said, it appears that figure does not take into account inflation, so the actual cost per year may be higher.
The Rosetta spacecraft is still working well and is expected to observe its target comet through 2015. The Philae lander did perform the incredible feat of landing on 67P on Wednesday, but it ended up in a shadowy spot that prevented it from gathering sunlight to stay awake. The lander is now in hibernation, perhaps permanently, but scientists have reams of data from the lander mission to pore over.
It’s been said that Rosetta, in following 67P as it gets closer to the Sun, will teach us more about cometary behavior and the origins of our Solar System. Is the mission and its social-media-sensation pictures worth the price? Let us know in the comments. More information on the infographic (and the spreadsheet of data) are available here.
A still of the Philae spacecraft bouncing off Comet 67P/Churyumov–Gerasimenko in an animation of Rosetta spacecraft images. The image was taken Nov. 12, 2014 at 10:35 a.m. EDT (3:35 p.m. UTC). Credit: ESA/Rosetta/NAVCAM; pre-processed by Mikel Canania
When the Philae lander arrived at its target comet last week, the little spacecraft landed three times in two hours before coming to a rest. While controllers could see this information from data coming in, they didn’t have any photographic proof — until now.
Here’s another cool thing about these images — some of the credit to Philae’s discovery comes through crowdsourcing! This is what the European Space Agency’s Rosetta blog said about who found this:
Credit for the first discovery goes to Gabriele Bellei, from the interplanetary division of Flight Dynamics, who spent hours searching the NAVCAM images for evidence of the landing.
Once the images were published, blog reader John Broughton posted a comment to report that he had spotted the lander in them (thank you, John). There was also quite some speculation by Rosetta blog readers in the comments section, wondering which features might be attributable to the lander. Martin Esser, Henning, and Kasuha in particular were among the first to make insightful observations on the topic, although many others have since joined in.
Last but not least, a careful independent review of the images was made by Mikel Catania from the earth observation division of Flight Dynamics, with the same conclusion. He also made the annotated animation shown here.
This goes to show you that while there is disappointment that Philae is in a long (perhaps permanent) sleep sooner than scientists hoped, data from the spacecraft will continue to be analyzed in the coming months and years. And don’t forget that the orbiting Rosetta spacecraft is in good health and will continue to return data on 67P as it draws closer to the Sun through 2015.
A still of the Philae spacecraft bouncing off Comet 67P/Churyumov–Gerasimenko in an animation of Rosetta spacecraft images. The image was taken Nov. 12, 2014 at 10:35 a.m. EDT (3:35 p.m. UTC). Credit: SA/Rosetta/NAVCAM; pre-processed by Mikel Catania
The Philae that could! The lander photographed during its descent by Rosetta. Credit: ESA/Rosetta/MPS for Rosetta Team/
I was twelve years old when Columbia disintegrated. Space exploration was not even a particular interest of mine at the time, but I remember exactly where I was when the news came. My dad and I were sitting in the living room of my childhood home, listening to NPR. I don’t really recall how I felt when they broke into our program with the news, but I remember well the two emotions that seemed to permeate the coverage that soon become constant: confusion and sadness. As I watched the almost surreal saga of ESA’s Philae this week, I found my mind wandering back to that day eleven years ago. That confusion rang out was hardly surprising; after all, things weren’t going right and we didn’t know why. But it was the sadness, I think, that drew my mind into the past. Many of the countless people watching Philae’s distress unfold before us weren’t merely disappointed that a decades-in-the-making experiment wasn’t going as planned. The word heartbroken kept springing to mind.
Let me be unequivocal: the loss of a machine, no matter how valuable or beloved, pales in comparison to the forfeit of human life. The astronauts lost on Columbia, like those snatched from us before and since, left behind families, friends, and a grateful world. But, why, then, did it seem to feel so similar to so many people?
“This is legitimately upsetting” a friend and colleague texted me on Friday as it became clear that the tiny lander’s batteries were beginning to run dry. She was far from alone in her sentiment. Across Twitter, people from around the world seemed to be lashing out against the helplessness of the situation.
Oh, wow. My head knows the mission is successful, and data is safe. My heart…wanted a different ending. #cometlanding
And, in conversations I had with other scientists at the 46th annual Division for Planetary Sciences meeting in Tucson, AZ this week, people seemed almost mournful at the prospect of the lander’s loss. These same researchers had laughed and cheered just days earlier when shown the crater made by NASA’s LADEE spacecraft upon its crash into the lunar surface.
The questions in my mind are numerous. What’s the cause of this inequity? Why do we seem to latch onto certain spacecraft and blithely ignore others? What is it that makes us become emotionally attached to machines in the first place?
In part, I think, our attachment comes from the unprecedented view offered to us by social media. In 1990, an event not so dissimilar from this one beset NASA’s Galileo spacecraft. Flying by the Earth on its way to Jupiter, Galileo had just attempted to unfurl its main antenna, a maneuver critical to the mission’s success. In mission control, they received the bad news: the antenna was stuck. But, the world did not break down in despair. In the days to come, stories would appear in newspapers and on the nightly news, but a world where even email was in its infancy lacked a means for the average citizen to follow along with every detail.
Nineteen years later, this would not be the case. As soon as it became clear to those in ESA headquarters that something had gone very wrong during Philae’s descent, we all knew. And, as data began to trickle in about one bounce off the surface and then another, we all cringed. When the last power drained from the lander’s batteries, we followed along, one volt after another. Philae may have been the pride of the ESA scientists and engineers who designed it, but it felt like it was ours.
But, it didn’t feel like ours in the way that a car or a plane or even a space station does. It felt like our friend. No doubt, this can be directly linked to the first person point of view employed for its Twitter account. Instead of the @Phillae2014 account reporting “the Ptolemy instrument has made a measurement,” we get “I just completed a @Philae_Ptolemy measurement!!” It seems like a small change, but it opens up a whole new world of connection with this distant traveler. At no time was this clearer than when things started to go wrong.
Hello! An update on life on #67P – Yesterday was exhausting! I actually performed 3 landings,15:33, 17:26 & 17:33 UTC. Stay tuned for more
How poignant is that? Two travelers talking to one another from across the solar system. But, as Philae’s time began to wind down, the messages tugged even more urgently on our heartstrings.
And, it all pales in comparison to the way China’s Yutu rover signed off when it looked like a malfunction might cause it to freeze to death on the Moon (original Chinese, CNN translation):
… my masters discovered something abnormal with my mechanical control system. …I’m aware that I might not survive this lunar night…
The sun has fallen, and the temperature is dropping so quickly… to tell you all a secret, I don’t feel that sad. I was just in my own adventure story – and like every hero, I encountered a small problem.
Goodnight, Earth. Goodnight, humanity.
Talk about heartbreaking.
This personal point of view combines particularly effectively with landers and rovers. These craft seem more human than ships like Cassini or Galileo, with their silent glide through deep space. When something goes wrong with a surface explorer, as it did with Philae or Yutu, it plays on our deepest fears. Every time we’re lost, the little voice of panic begins to creep into our thoughts: “what if this is the time that I can’t get back?” Reading the “thoughts” of a tiny spacecraft, lost and alone and confused, puts us right there ourselves. As mission controllers edged towards desperation in their attempts to save the stricken explorer, we knew how that delirious urgency felt. Our attachment becomes almost unavoidable.
So, what does this all mean? I think it’s a clear signal that people are engaged by the exploration of space. When it comes to us in the right way, on our terms, it’s a big hit. By anthropomorphizing these robots, we humanize the science that they do. Suddenly a machine more than 500 million kilometers away becomes more relatable than the scientists next door who control it. Perhaps ESA, NASA, and other space agencies can extend this relationship even further. Rather than springing to “life” upon liftoff, spacecraft can share with us their view of the entire process, starting not from space, but from the first drawings on an engineer’s blackboard.
One thing’s for sure, though. A relationship like that won’t make times like these any easier to handle.
Left Panel: SNR1987A as seen by the Hubble Space Telescope in 2010.Middle Panel: SNR1987A as seen by the Australia Telescope Compact Array (ATCA) in New South Wales and the Atacama Large Millimeter/submillimeter Array (ALMA) in Chile. Right Panel: A computer generated visualisation of the remnant showing the possible location of a Pulsar. Credit: ATCA & ALMA Observations & data - G. Zanardo et al. / HST Image: NASA, ESA, K. France (University of Colorado, Boulder), P. Challis and R. Kirshner (Harvard-Smithsonian Center for Astrophysics)
A team of Australian astronomers has been busy utilizing some of the world’s leading radio telescopes located in both Australia and Chile to carve away at the layered remains of a relatively new supernova. Designated as SN1987A, the 28 year-old stellar cataclysm came to Southern Hemisphere observer’s attention when it sprang into action at the edge of the Large Magellanic Cloud some two and a half decades ago. Since then, it has provided researchers around the world with a ongoing source of information about one of the Universe’s “most extreme events”.
Representing the University of Western Australia node of the International Centre for Radio Astronomy Research, PhD Candidate Giovanna Zanardo led the team focusing on the supernova with the Australia Telescope Compact Array (ATCA) in New South Wales. Their observations took in the wavelengths spanning the radio to the far infrared.
“By combining observations from the two telescopes we’ve been able to distinguish radiation being emitted by the supernova’s expanding shock wave from the radiation caused by dust forming in the inner regions of the remnant,” said Giovanna Zanardo of the International Centre for Radio Astronomy Research (ICRAR) in Perth, Western Australia.
“This is important because it means we’re able to separate out the different types of emission we’re seeing and look for signs of a new object which may have formed when the star’s core collapsed. It’s like doing a forensic investigation into the death of a star.”
“Our observations with the ATCA and ALMA radio telescopes have shown signs of something never seen before, located at the centre or the remnant. It could be a pulsar wind nebula, driven by the spinning neutron star, or pulsar, which astronomers have been searching for since 1987. It’s amazing that only now, with large telescopes like ALMA and the upgraded ATCA, we can peek through the bulk of debris ejected when the star exploded and see what’s hiding underneath.”
A video compilation showing Supernova Remnant 1987A as seen by the Hubble Space Telescope in 2010, and by radio telescopes located in Australia and Chile in 2012. The piece ends with a computer generated visualization of the remnant showing the possible location of a Pulsar. Credit: Dr Toby Potter, ICRAR-UWA, Dr Rick Newton, ICRAR-UWA
But, there is more. Not long ago, researchers published another paper which appeared in the Astrophysical Journal. Here they made an effort to solve another unanswered riddle about SN1987A. Since 1992 the supernova appears to be “brighter” on one side than it does the other! Dr. Toby Potter, another researcher from ICRAR’s UWA node took on this curiosity by creating a three-dimensional simulation of the expanding supernova shockwave.
“By introducing asymmetry into the explosion and adjusting the gas properties of the surrounding environment, we were able to reproduce a number of observed features from the real supernova such as the persistent one-sidedness in the radio images”, said Dr. Toby Potter.
So what’s going on? By creating a model which spans over a length of time, researchers were able to emulate an expanding shock front along the eastern edge of the supernova remnant. This region moves away more quickly than its counterpart and generates more radio emissions. When it encounters the equatorial ring – as observed by the Hubble Space Telescope – the effect becomes even more pronounced.
A visualization showing how Supernova1987A evolves between May of 1989 and July of 2014. Credit: Dr Toby Potter, ICRAR-UWA, Dr Rick Newton, ICRAR-UWA
“Our simulation predicts that over time the faster shock will move beyond the ring first. When this happens, the lop-sidedness of radio asymmetry is expected to be reduced and may even swap sides.”
“The fact that the model matches the observations so well means that we now have a good handle on the physics of the expanding remnant and are beginning to understand the composition of the environment surrounding the supernova – which is a big piece of the puzzle solved in terms of how the remnant of SN1987A formed.”
New research suggests that Dark Matter may exist in clumps distributed throughout our universe. Credit: Max-Planck Institute for Astrophysics
We know dark matter exists. We know this because without it and dark energy, our Universe would be missing 95.4% of its mass. What’s more, scientists would be hard pressed to explain what accounts for the gravitational effects they routinely see at work in the cosmos.
For decades, scientists have sought to prove its existence by smashing protons together in the Large Hadron Collider. Unfortunately, these efforts have not provided any concrete evidence.
Hence, it might be time to rethink dark matter. And physicists David M. Jacobs, Glenn D. Starkman, and Bryan Lynn of Case Western Reserve University have a theory that does just that, even if it does sound a bit strange.
In their new study, they argue that instead of dark matter consisting of elementary particles that are invisible and do not emit or absorb light and electromagnetic radiation, it takes the form of chunks of matter that vary widely in terms of mass and size.
As it stands, there are many leading candidates for what dark matter could be, which range from Weakly-Interacting Massive Particles (aka WIMPs) to axions. These candidates are attractive, particularly WIMPs, because the existence of such particles might help confirm supersymmetry theory – which in turn could help lead to a working Theory of Everything (ToE).
According to supersymmetry, dark-matter particles known as neutralinos (aka WIMPs) annihilate each other, creating a cascade of particles and radiation. Credit: Sky & Telescope / Gregg Dinderman.
But so far, no evidence has been obtained that definitively proves the existence of either. Beyond being necessary in order for General Relativity to work, this invisible mass seems content to remain invisible to detection.
According to Jacobs, Starkman, and Lynn, this could indicate that dark matter exists within the realm of normal matter. In particular, they consider the possibility that dark matter consists of macroscopic objects – which they dub “Macros” – that can be characterized in units of grams and square centimeters respectively.
Macros are not only significantly larger than WIMPS and axions, but could potentially be assembled out of particles in the Standard Model of particle physics – such as quarks and leptons from the early universe – instead of requiring new physics to explain their existence. WIMPS and axions remain possible candidates for dark matter, but Jacobs and Starkman argue that there’s a reason to search elsewhere.
“The possibility that dark matter could be macroscopic and even emerge from the Standard Model is an old but exciting one,” Starkman told Universe Today, via email. “It is the most economical possibility, and in the face of our failure so far to find dark matter candidates in our dark matter detectors, or to make them in our accelerators, it is one that deserves our renewed attention.”
After eliminating most ordinary matter – including failed Jupiters, white dwarfs, neutron stars, stellar black holes, the black holes in centers of galaxies, and neutrinos with a lot of mass – as possible candidates, physicists turned their focus on the exotics.
Ongoing experiments at the Large Hadron Collider have so far failed to produce evidence of WIMPs. Credit: CERN/LHC/GridPP
Nevertheless, matter that was somewhere in between ordinary and exotic – relatives of neutron stars or large nuclei – was left on the table, Starkman said. “We say relatives because they probably have a considerable admixture of strange quarks, which are made in accelerators and ordinarily have extremely short lives,” he said.
Although strange quarks are highly unstable, Starkman points out that neutrons are also highly unstable. But in helium, bound with stable protons, neutrons remain stable.
“That opens the possibility that stable strange nuclear matter was made in the early Universe and dark matter is nothing more than chunks of strange nuclear matter or other bound states of quarks, or of baryons, which are themselves made of quarks,” said Starkman.
Such dark matter would fit the Standard Model.
This is perhaps the most appealing aspect of the Macros theory: the notion that dark matter, which our cosmological model of the Universe depends upon, can be proven without the need for additional particles.
Still, the idea that the universe is filled with a chunky, invisible mass rather than countless invisible particles does make the universe seem a bit stranger, doesn’t it?
The animated image below provides strong evidence that Philae touched down for the first time almost precisely where intended. The animation comprises images recorded by Rosetta's navigation camera as the orbiter flew over the (intended) Philae landing site on November 12th. The dark area is probably dust raised by the craft on touchdown. The boulder to the right of the circle is seen in detail in the photo below. Credit: ESA/Rosetta/NAVCAM – CC BY-SA IGO 3.0
Contact with the Philae lander was lost at 6:36 p.m. (CST) this evening, November 14th, before the normal loss of signal when Rosetta orbits below the lander’s horizon. Without sunlight to juice up its solar panels and recharge the its batteries, the craft will remain in “idle mode” – maybe for a long time. All its instruments and most systems on board have been shut down.
“Prior to falling silent, the lander was able to transmit all science data gathered during the First Science Sequence,” says DLR’s Stephan Ulamec, Lander manager. All of the science instruments were deployed, including the instruments that required mechanical movement, such as APXS, MUPUS, and the drill, which is designed to deliver samples to the PTOLEMY and COSAC instruments inside the lander.
This image was taken by Philae’s down-looking descent ROLIS imager when it was about 131 feet (40 meters) above the surface of the comet. The surface is covered by dust and debris ranging from millimeter to meter sizes. The large block in the top right corner is 16.4 feet (5 m) in size. In the same corner the structure of the Philae landing gear is visible. Credit: ESA/Rosetta/Philae/ROLIS/DLR
No contact will be possible unless maneuvers by controllers on the ground nudge Philae back into a sunnier spot. On its third and final landing, it unfortunately came to rest in the shadow of one of the comet’s many cliffs. Contrary to earlier reports (or speculations), Valentina Lommatsch from the German Aerospace Center explained that all three of Philae’s legs are on the ground. But the lander appears to be tipped up at an angle because one of the scenes from the panorama (below) shows mostly sky.
Jagged cliffs and prominent boulders are visible in this photo taken by OSIRIS on September 5, 2014 from a distance of 38.5 miles (62 km) and processed/colorized by Marco Faccin and Elisabetta Bonora. Credit: ESA/Rosetta/MPS for OSIRIS team
This evening, mission controllers sent commands to rotate the lander’s main body to which the solar panels are fixed. This may have exposed more panel area to sunlight, but we won’t know until Saturday morning (Nov. 15) at 4 a.m. (CST) when the Rosetta orbiter has another opportunity to listen for Philae’s signal.
Our last panorama from Philae? This image was taken with the CIVA camera; at center Philae has been added to show its orientation on the surface. Credit: ESA
The batteries were designed to power the probe for about 55 hours. Had Philae landed upright in the targeted region, its solar panels would have been out in the open and soaking up the sunlight needed for multiple recharges. There’s also the possibility that months from now, as seasons progress and illumination changes on the comet, that the Sun will rise again over the probe.
We may hear from the lander again or not. But if not, all the science instruments were deployed in the first two days of landing and data has been received.
* Update 7 a.m. (CST) November 15: A bit of good news! Rosetta has regained contact with Philae during the overnight communication pass, confirming that the lander still has power. The bad news is that the batteries will be completely drained sometime today.
Deputy flight director Elsa Montagnon watches data flow from Philae on the surface of comet 67P/C-G Credit: ESAScience data transmitted by Philae on November 14th. Credit: ESA
Orion flight test profile for the Exploration Flight Test-1 (EFT-1) launching on Dec. 4, 2014. Credit: NASA
After moving out to the launch pad earlier this week, NASA’s first Orion spacecraft was hoisted atop the most powerful rocket in the world and awaits blastoff from Cape Canaveral, Florida, in early December on a critical test flight that will pave the way for human missions to deep space for the first time in more than four decades since NASA’s Apollo moon landing missions ended in 1972.
NASA’s cool new set of infographics above and below explain 8 key events on Orion’s Exploration Flight Test-1 (EFT-1) mission and its first trip to orbit and back.
Orion will lift off on a Delta IV Heavy rocket on its inaugural test flight to space on the uncrewed EFT-1 mission at 7:05 a.m. EST on December 4, 2014, from Space Launch Complex 37 (SLC-37) at Cape Canaveral Air Force Station in Florida.
The two-orbit, four and a half hour Orion EFT-1 flight around Earth will lift the Orion spacecraft and its attached second stage to an orbital altitude of 3,600 miles, about 15 times higher than the International Space Station (ISS) – and farther than any human spacecraft has journeyed in 40 years.
Launch – It’s going to be loud. It’s going to be bright. It’s going to be smoky. Engines are fired, the countdown ends, and Orion lifts off into space atop the United Launch Alliance Delta IV Heavy rocket from the launch pad at Cape Canaveral in Florida. Credit: NASA
EFT-1 will test the rocket, second stage, jettison mechanisms, as well as avionics, attitude control, computers, and electronic systems inside the Orion spacecraft.
Then the spacecraft will carry out a high speed re-entry through the atmosphere at speeds approaching 20,000 mph and scorching temperatures near 4,000 degrees Fahrenheit to test the heat shield, before splashing down for a parachute assisted landing in the Pacific Ocean.
Exposure – It’s time to fly! The protective panels surrounding the service module are jettisoned and the launch abort system separates from the spacecraft. Credit: NASARe-ignition – Orbit 1 is complete! The upper stage will now fire up again to propel Orion to an altitude of 3,600 miles during its second trip around Earth. Credit: NASASeparation – It’s now time to prepare for reentry. The service module and upper stage separate so that only the crew module will return to Earth. Credit: NASAOrientation – Orion’s first flight will be uncrewed, but that doesn’t mean we can allow Orion to return to Earth upside down. This test flight will help us test the control jets to ensure that they can orient the capsule in the correct reentry position. Credit: NASAHeating – Things are heating up as Orion slams into the atmosphere at almost 20,000 mph and encounters temperatures near 4,000 degrees F. Credit: NASADeploy – After initial air friction slows the capsule from 20,000 mph, Orion will still be descending at 300 mph—too fast for a safe splashdown. A sequence of parachute deployments will create drag to further slow the spacecraft to a comfortable 20 mph. Credit: NASALanding – Orion will splashdown in the Pacific Ocean off the coast of Baja California, where it will be recovered with help from the United States Navy. Credit: NASA
Here’s what Orion’s ocean splashdown and recovery by Navy divers will look like:
US Navy divers on four boats attached tow lines to the Orion test capsule and guide it to the well deck on the USS Arlington during Aug. 15, 2013, recovery test at Norfolk Naval Base, VA. Credit: Ken Kremer/kenkremer.com
Orion is NASA’s next generation human rated vehicle that will carry America’s astronauts beyond Earth on voyages venturing farther into deep space than ever before – beyond the Moon to Asteroids, Mars, and other destinations in our Solar System.
The United Launch Alliance Delta IV Heavy rocket is the world’s most powerful rocket. The triple barreled Delta IV Heavy booster is the only rocket sufficiently powerful to launch the 50,000 pound Orion EFT-1 spacecraft to orbit.
The first stage of the mammoth Delta IV Heavy generates some 2 million pounds of liftoff thrust.
Watch for Ken’s Orion coverage, and he’ll be at KSC for the historic launch on Dec. 4.
Stay tuned here for Ken’s continuing Orion and Earth and planetary science and human spaceflight news.
Does the atmosphere of Venus possess upper atmospheric phenomena similar to the Earth, such as aurora or nightglow?
Now, a recent announcement out of the American Astronomical Society’s 46th annual meeting of the Division of Planetary Science being held this week in Tucson, Arizona has shed new light on the dilemma.
The discovery was announced on Wednesday, November 12th at the 46th AAS meeting and was made as a collaborative effort by researchers from New Mexico State University at Las Cruces, the Stanford Research Institute (SRI) International, the University of Colorado at Boulder, the University of Koln and University of Munich, Germany, the European Space and Technology Center in the Netherlands and the Institut de Recherche en Astrophysique et Planétologie, in France.
For the study, researchers observed Venus from December 2010 to July 2012 using the Astrophysical Research Consortium (ARC)Echelle Spectrograph and the ARC 3.5 metre telescope located at Apache Point near Sunspot, New Mexico.
Timing was crucial, as the Sun was coming off of a profound deep minimum through 2009 and just beginning to become active with the start of solar cycle #24. Observers were looking for activity along the 5577.3 angstrom wavelength known as the “oxygen green line.” Activity had not been seen at this wavelength on the nighttime side of Venus since 2004.
The altitude drop in the Venusian atmosphere measured in the study. Credit : Credit: DPS press release/C. Gray/New Mexico State University.
“These are intriguing results, suggesting that it is possible to have aurora on non-magnetic planets,” said Candace Gray, Astronomer and NASA Earth and Space Science Fellow at Las Cruces and lead researcher in the study. “On Venus, this green line has been seen only intermittently.”
Earth is the oddball among the terrestrial planets in the inner solar system with its robust magnetic field. On Earth, aurorae occur when said field captures charged particles ejected from the Sun and funnels them in towards the poles. Events seen in the study tended to drop 140 to 120 kilometres in altitude in the Venusian atmosphere, highly suggestive of auroral activity seen in the ionosphere of Earth.
Researchers were fortunate during one of the recent runs at Apache Point that the Sun kicked off a coronal mass ejection that headed Venus’s way. During the July 2012 solar storm, the team detected one of the brightest green line emissions that had ever been detected by observers on Earth.
The 3.5 metre telescope at Apache Point, in this case, being used for lunar ranging experiments. Credit: M3long/Wikimedia Commons image.
This demonstrates that perhaps, a magnetic field is optional when it comes to auroral activity, at least in the case of the planet Venus. Located only 0.7 astronomical units (108.5 million kilometres) from the Sun, our tempestuous star actually wraps the planet with its very own magnetotail.
Researchers are also looking to compare their results with observations from the European Space Agency’s Venus Express orbiter which arrived at the planet on April 2006.
“Currently, we are using observations from VIRTIS on Venus Express to try and detect the green line,” Gray told Universe Today. “We had coordinated ground based observations with them this past February, and we detected the green line from the ground when they were observing the night side limb. Additionally, we are using the Electron Spectrometer and ASPERA-4 to observe how the electron energy and density changes in the atmosphere after coronal mass ejection impacts.”
This also raises the interesting possibility that NASA’s MAVEN spacecraft — which recently arrived in orbit around Mars — might just detect similar activity in the tenuous Martian atmosphere as well. Like Venus, the Red Planet also lacks a global magnetic field.
Could this glow be connected with spurious sightings of the “Ashen Light of Venus” that have cropped up over the centuries?
Of course, ashen light, also known as Earthshine on the dark limb of the Moon, is easily explained as sunlight reflected back from the Earth. Moonless Venus, however, should be ashen light free.
“The green line emission that we see is brightest on the limb (edge) of the planet,” Gray told Universe Today. “We’re sure that there is emission all along the nightside, but because of the optical depth, it appears much brighter on the limb of the planet. I think it would be too faint to detect with the naked eye.”
Nightglow has been a leading suspect for ashen light on the Venusian nightside, and a similar green line emission detection rivaling the 2012 event was made by Tom Slanger using the Keck I telescope 1999.
Other proposed suspects over the centuries for ashen light on Venus include lightning, volcanism, light pollution (!) from Venusian cities, or just plain old observer error.
Certainly, future observations are needed to cinch the solar activity connection.
“We will likely observe Venus again from Apache Point the next time Venus is visible to us in June 2015,” Gray told Universe Today. “We will continue looking at Venus Express observations until the craft dies in the atmosphere.”
Venus turns its night time back towards us during the 2012 transit of the Sun, as seen from NASA’s Solar Dynamics Observatory (Credit: NASA/SDO).
Venus can currently be seen crossing through the field of view of SOHO’s LASCO C3 camera. After spending most of 2014 in the dawn sky, Venus will emerge from behind the Sun low in the dusk to head towards greatest elongation in the evening sky on June 6th, 2015. And from there, Venus will once again slender towards a crescent, presenting its nightside towards Earth, and just perhaps, continuing to present a lingering mystery of modern astronomy.
NASA’s Orion Program manager Mark Geyer discusses Orion EFT-1 mission. Credit: Ken Kremer - kenkremer.com
A ride into space, a high-speed re-entry and a safe parachute deployment. That’s what NASA is hoping for when the Orion vehicle soars into space for a planned flight test next month. Eventually, this spacecraft will carry humans on journeys around the solar system, if all goes to plan.
The dramatic video above shows some of the testing Orion has passed so far, culminating in an animation showing the plans for the flight test. For more details on what to expect, check out Universe Today’s Ken Kremer’s article from a few days ago. Below is a gallery of Orion images from over the past couple of years.
NASA’s completed Orion EFT 1 crew module loaded on wheeled transporter during move to the Payload Hazardous Servicing Facility (PHFS) on Sept. 11, 2014 at the Kennedy Space Center, FL. Credit: Ken Kremer – kenkremer.comNASA Administrator Charles Bolden discusses NASA’s human spaceflight initiatives backdropped by the service module for the Orion crew capsule being assembled at the Kennedy Space Center. Credit: Ken Kremer/kenkremer.comDive teams attach tow lines to Orion test capsule during Aug. 15 recovery test at Norfolk Naval Base, VA. Credit: Ken Kremer/kenkremer.comOrion EFT-1 crew cabin and full scale mural showing Orion Crew Module atop Service Module inside the O & C Building at the Kennedy Space Center, Florida. Credit: Ken Kremer/kenkremer.com
