- Vostochny Report, Part 1: All the Right People
- Nanodust Particles in the Interplanetary Medium
- Latest MESSENGER Data Delivery Includes New Targeted Mosaics of Mercury
- Arianespace Wins SES-15 Launch Contract
- Exorings on the Horizon
- NanoRacks Completes Historic Third Round of Space Station CubeSat Deployments
- Subaru Telescope Observes Rapid Changes in a Comet's Plasma Tail
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Posted: 07 Mar 2015 03:36 PM PST
Clear skies, snowy terrain and never-ending freezing cold - the winter scenery is where all the space launch action will take place. But now, only a white helicopter lands near the missile assembly complex. "You will need all the resources, all that you have - human, material, financial!" yells the man who has just disembarked the chopper. He doesn’t seem to be interested in how the desired supplies will be collected, focusing only on the end result. “I want to make sure personally that all the key people are here,” he says vigorously. “All decisions will be taken only here and also executed here.” In fact, Moscow seems like a faraway land, thousands of miles away from here.
Russian Deputy Prime Minister Dmitry Rogozin arrives at Vostochny cosmodrome construction site every month. On Feb. 27, as usual, he went to inspect the facilities, and then held a working meeting with representatives of the Russian Federal Space Agency Roscosmos and Federal Agency for Special Construction Spetsstroy.
The visits to the Vostochny cosmodrome construction site in Russia’s Far East Amur region are to assure the government that work continues amid many disruptive obstacles. The country’s new window to space is expected to reduce Russia’s dependency on the Baikonur cosmodrome in Kazakhstan, which is on lease from the Kazakh government until 2050.
Rogozin oversees Russia's space sector and is very active in the Vostochny project. In 2011, he was appointed as Deputy Prime Minister, in charge of defense and space industry. Last year, cameras had been installed throughout the construction site and linked to his office in Moscow so that he could monitor the workflow and root out “slackers.” He often shares pictures of his visits to the cosmodrome on his Facebook page. Now, the live stream from Vostochny is also available to the public on the Roscosmos website, allowing people to watch the facility being constructed.
“This is the people's construction, and I want cameras to broadcast not only on my computer in Moscow,” Rogozin said in January. “I believe that it will allow people to monitor what is happening on the construction site.”
Vostochny is estimated to be two to three months behind schedule. While visiting the construction site in February, Rogozin put all the blame for the delays on Spetsstroy.
"I remind you that the start of construction works at the Vostochny cosmodrome was the order of the President of the Russian Federation, according to which the sole executor of this works is Spetsstroy Russia, not “Dalspetsstroy" neither any other daughter nor granddaughter companies,” Rogozin said. “Therefore, Spetsstroy bears full responsibility for the execution of all works."
Alexander Mordovets, the Deputy Director of Spetsstroy, was defending his company by claiming that the bureaucracy is slowing down the progress. He complained about the large amount of documentation that has to be completed by the workers.
Then Rogozin warned that if the orders are not executed the company will be punished with “the most severe penalties” as he described it.
Thankfully, the compromise has been reached as Rogozin agreed to assign more manpower to the construction site and to send more staff to complete all the necessary paperwork. He also gave Mordovets the full authority to organize the work at Vostochny.
"There must be complete unity of command. We have agreed to that today,” Rogozin said. “Alexander Alexandrovich Mordovets received full power, all the rights, and responsibilities for the organization of all activities to fully overcome the lag.”
The right people on the right place are important for Vostochny to allow the first launch which is now planned on Dec. 25, 2015. "As of today, the launch date is set for December 25. The date may later change insignificantly," Russian news agency TASS reports. The race is now on to install the metal structures of the launch pad and the myriad of systems supporting launch operations. The internal outfitting had actually started during 2014, however the bulk of this work would have to be completed in the first half of 2015.
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Posted: 07 Mar 2015 02:33 PM PST
Dust particles smaller than about a wavelength of light are abundant in our solar system, created by collisions between asteroids and from the evaporation of comets. As they scatter sunlight, these particles produce the zodiacal light, the glow in the night sky that stretches along the zodiac. The zodiacal light is most easily seen after sunset or before sunrise, though it is faint enough that even moonlight can mask it. Nanodust particles are about ten times smaller than normal dust -- too small to efficiently scatter sunlight. They can be sensed by spacecraft, however, because when they impact the spacecraft they generate puffs of ionized gas and electrical pulses that instruments can detect.
The Solar TErrestrial RElations Observatory (STEREO) spacecraft has been detecting nanodust pulses since its launch in 2007, and previous studies of these events have confirmed the general picture that these tiny particles are an important constituent of the solar system.
The corona of the Sun, the hot (over a million kelvin), gaseous outer region of its atmosphere, is threaded by intense magnetic fields. The fields loop and twist, stirred by the motions of the hot gas in the underlying atmosphere. When these loops snap, they eject energetic charged particles into the solar wind in events called coronal mass ejections.
Nanodust particles carry a slight electric charge, and because of that, the solar wind should be able to redistribute them as it blows toward Earth through interplanetary space.
CfA (Harvard-Smithsonian Center for Astrophysics) astronomer Gaetan Le Chat and his colleagues have analyzed seven years of data on nanodust obtained from the STEREO spacecraft and found that coronal mass ejections do indeed appear to accelerate and concentrate nanodust particles, leading to increased rates of impact on the spacecraft during periods of solar activity.
The scientists also noted longer-term, regular variations in the rate of nanodust impacts, and propose from the periodic behavior that the gravitational influences of Mercury and Venus are responsible, perhaps by perturbing the tails of comets that have passed through the inner solar system, leading to a higher production of nanodust.
Credit: cfa.harvard.edu
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Posted: 07 Mar 2015 02:14 PM PST
NASA's Planetary Data System (PDS) on Friday released data collected from the MErcury Surface, Space ENvironment, GEochemistry, and Ranging (MESSENGER) mission during its 37th through 42nd months in orbit about Mercury. NASA requires that all of its planetary missions archive their data in the PDS, which makes available documented, peer-reviewed data to the research community. This 13th delivery from the MESSENGER team includes formatted raw and calibrated data collected through 17 September 2014 by the spacecraft's seven science instruments and the Radio Science investigation. Spacecraft, planet, instrument, camera-matrix, and events (SPICE) metadata from launch through the period of this release are also available.
The delivery includes new advanced products created from data acquired through March 17, 2014, encompassing the first six full Mercury solar days of MESSENGER orbital operations. Now available are global high-incidence east- and west-illumination maps and high-resolution regional targeted mosaics acquired by the Mercury Dual Imaging System (MDIS),
"Images for the global high-incidence maps were acquired when the Sun was very low on the horizon, which accentuates our view of surface topography because even small geologic features catch the Sun and cast long shadows," explained Brett Denevi, a planetary geologist at the Johns Hopkins University Applied Physics Laboratory (APL), in Laurel, Md., and the Deputy Instrument Scientist for MDIS. "MDIS took images just after dawn and just before dusk, because asymmetrical features, such as thrust faults, are likely more visible in one illumination direction than the other. Moreover, crater walls and features that appear in shadow in one map will be illuminated in the other."
Creating the global maps, as with the high-incidence mosaics, requires a compromise, she explained. "In order to obtain coverage as close to global as possible, we have to sacrifice image resolution in many areas. These global maps are complemented by the regional targeted mosaics, which provide high-resolution images of selected sites of high scientific interest."
"The targets were chosen by the science team as areas for further investigation, and they have provided some of our most spectacular views of small-scale features such as hollows, fresh impact craters, and volcanic vents," she said. "In some cases these views are monochrome images acquired with the narrow-angle camera, and in others we opted for images acquired using the color filters of the slightly lower-resolution wide-angle camera."
This PDS also includes viewing normalizations, flux maps, and two-dimensional pitch-angle products from the Fast Imaging Plasma Spectrometer (FIPS) on the Energetic Particle and Plasma Spectrometer (EPPS) instrument.
"The new FIPS PDS data products simultaneously provide users with the most often used two-dimensional and three-dimensional data products, as well as the tools needed to create their own," explained Jim Raines, a space plasma physicist at the University of Michigan and FIPS Instrument Scientist. "The new angular flux maps provide the best visualization of the direction that plasma ions are traveling in Mercury's space environment, which is a key quantity for understanding the behavior of the system. The new energy-resolved pitch-angle distributions give this information relative to the local magnetic field, which can be useful for identifying ions that are expected to impact Mercury's surface and cause space weathering."
"The viewing normalizations product contains the time-dependent rotation matrices needed for users to form their own versions of these and other multi-dimensional products, with arbitrary time accumulations," he added.
The ACT-REACT QuickMap interactive Web interface to MESSENGER data has been updated to incorporate orbital data from this release from the MDIS instrument and the Mercury Atmospheric and Surface Composition Spectrometer (MASCS) instrument's Visible and Infrared Spectrograph (VIRS). QuickMap can be accessed via links on the MESSENGER websites at http://messenger.jhuapl.edu/ and http://www.nasa.gov/
The data for this release are available online at http://pds.nasa.gov/
Credit: messenger.jhuapl.edu
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Posted: 07 Mar 2015 01:32 PM PST
SES has chosen Arianespace to launch its new, all-electric telecommunications satellite, SES-15. The launch service contract was signed by Karim Michel Sabbagh, Chairman and CEO of SES, and Stéphane Israël, Chairman and CEO of Arianespace, and marks Arianespace's 41st contract with SES. The contract signing ceremony was held on Mar. 6 at SES headquarters in Betzdorf, Luxembourg. It was attended by French President François Hollande, His Royal Highness Henri, Grand Duke of Luxembourg, and Xavier Bettel, Prime Minister of Luxembourg. "I would like to personally thank SES for reenergizing our long-standing partnership, reaching back over a quarter of a century, with this 41st contract between our companies. We are especially proud to be able to announce this contract in a ceremony attended by the French and Luxembourg highest authorities," Israël said.
SES-15 will be launched by an Ariane 5 during the second quarter of 2017 from the Guiana Space Center, Europe's Spaceport in Kourou, French Guiana.
Arianespace and SES have developed an exceptional partnership that reaches back more than 25 years. SES-15 marks the 41st launch contract signed by Arianespace with the SES group (Euronext Paris and Luxembourg bourse: SESG). SES-15 is also the second SES satellite with all-electric propulsion to call on an Arianespace launch, following SES- 12 in January 2015.
Martin Halliwell, CTO of SES, stated: "For more than twenty-five years, Arianespace and SES have developed an exceptional partnership. Not only is SES-15 the 41st launch service contract signed with Arianespace, but it is also the second all-electrical satellite to be launched by Arianespace, following the announcement of the award of the launch contract of SES-12 in January 2015. The contracts with Arianespace and Airbus Defence and Space clearly demonstrate the important roles played for us by the European aerospace industry and French industry, with a view to realising our strategy and achieving our growth targets across all markets and sectors."
Weighing 2,300 kg at launch, SES-15 will be located at 129° West, a new orbital position enabling SES to provide services to North America. SES-15 will carry a hybrid payload, with additional Ku-band wide beams and Ku- band as well as Ka-band High Throughput Satellite (HTS) capability. The satellite will be equipped with an electric propulsion system for orbit raising and in-orbit maneuvers. Offering a design life of 15 years, this multi-application satellite will also provide extended capacity and coverage over the main airline routes across the continent, as well as other traffic intensive data applications, such as governments, VSAT networks and the maritime sector.
"SES has chosen Arianespace for the second time since the beginning of the year to launch one of its satellites. These contracts include both fleet renewal, with the SES-12, and fleet expansion, with the SES-15. These two all-electric satellites, the first in the SES fleet, confirm the technology trend now shaping the telecom satellite sector. SES's continued trust in Arianespace also shows that Ariane 5 addresses the resulting requirements," Israël said.
Credit: arianespace.com
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Posted: 07 Mar 2015 12:45 PM PST
Astronomers from the Harvard-Smithsonian Center for Astrophysics and the University of Antioquia (Medellin-Colombia), have devised a novel method for identifying rings around extrasolar planets (exorings). The method is relatively simple and can be used to rapidly analyze large photometric database and to find a list of exoring candidates deserving further analysis. Exoplanetary science is one of the most prolific sources of astronomical discoveries since the invention of telescopes. Once you get used to a suprising finding, such as the discovery of an Earth-twin, another exciting discovery beckons, capturing the imagination of scientists and non-scientists. Although we cannot predict the next exoplanetary discovery, several breakthroughs, such as the discovery of the first exomoon or the direct image of an Earth-like planet, have been in the line for years. Exorings are also one of these long-awaited discoveries.
Recently, a group of astronomers lead by Matt Kenworthy of the Leiden Observatory and Erik Mamajek of the Rochester University, announced the discovery of a huge disk orbiting the "Super-Jupiter" J1407b. Beside the initial excitement, the actual nature of the object and its "rings" is still debated. The planet could actually be a brown-dwarf and the rings a version in miniature of a protoplanetary disk.
Rings are common in the Solar System. Jupiter, Saturn, Uranus and Neptune have rings of different sizes. Even smaller objects, such as asteroids and cometary nuclei, could have their own rings. Searching for ringed planets beyond the Solar System is as natural as searching for moons and magnetic fields, two other common phenomena associated with planets.
Jorge I. Zuluaga, Associate Professor in the Institute of Physics of the University of Antioquia and Visitor Scholar of the Harvard-Smithsonian Center for Astrophysics (CfA), David Kipping, Menzel Fellow in the CfA and leading expert in exoplanetary research, and two of their undergraduate and undergraduate students, Mario Sucerquia and Jaime Andrés Alvarado, have discovered a fast and novel method for identifying exorings in large photometric databases. The method could pave the way for the discovery of the first exorings in the very near future. Their ideas has been accepted for publication in a forecoming issue of Astrophysical Journal Letters. An eprint version of the paper is already available in the arXiv repository.
One of the most exciting aspect of the new method is its simplicity: a ringed-planet will produce a "deeper" and longer transit than that produced by a non-ringed twin.
But, how can a "deeper" and longer transit of a ringed planet be distinguished from the same effect caused by a larger one?. If a Jupiter-sized planet have a ring, Astronomers on Earth, studying the transit of the planet in front of its host star, will think the object is much larger than it actually is. Finding planet much larger than jupiter is not common. Only brown dwarf and small stars are that big. In photometric survey, such as that of the Kepler Space Telescope, objects that appear bigger than expected, are normally tagged as "false positives". According to Zuluaga and Kipping, we should start looking carefully on these false positives. True "ringed jewels" could be hidden among this apparent "trash".
A second idea exploits the so-called "Asterodensity-profiling effect". Planetary transits have a wealth of information, not only about the planet, but about the star itself. If we combine the transit depth (that depends on the size of the star) and the duration of the transit (that depends on orbital velocity and hence on the stellar mass) we can estimate the density of the star. This transit-based stellar density could be then compared with the density measured independently with another method (asteroseismology for example). If they do not coincide, something is really wrong with our assumptions about the planet or its orbit. Zuluaga, Kipping et al. have demonstrated that the presence of Rings leads to a systematic underestimation of stellar density. This effect is called the "Photo-ring effect".
The identification of rings with this novel method is not enough to claim the discovery and confirmation of an exoring. Once a list of suitable candidates be selected, a battery of powerful and efficient methods must be used to actually confirm the existence of exorings around some of those candidates. Even in that case, the new method has the potential to provide the statistical distribution of exorings properties, well before we discover a significant number of them.
Credit: astronomia-udea.co
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Posted: 07 Mar 2015 12:26 PM PST
NanoRacks, the Go-To CubeSat Deployment Company, has announced the successful completion of it’s third full round of CubeSat deployments from the International Space Station. Deployed from the NanoRacks CubeSat Deployer were 16 CubeSats since the February 27, 2015 deployment window opened. Included were 12 Planet Labs Doves (10 Flock-1B, 2 Flock-1D’), Spaceflight Services & MIT’s MicroMAS, San Jose University and Greece’s LambdaSat, NASA Ames’ TechEdSat-4, and the GEARRSat CubeSat. “We are delighted to show once again that the International Space Station is an ideal deployment platform for satellites,” said NanoRacks CEO Jeffrey Manber. “And we thank our friends at NASA and JAXA for working to make this program a reality.”
The latest deployment cycle was made possible only by a historic on-orbit repair of hardware that had earlier not performed. It involved close coordination between the NanoRacks team and officials from the ISS space agencies.
The NanoRacks CubeSat Deployer (NRCSD) began deployments in January 2014. In just 13 months, NanoRacks has established itself as the ‘go-to CubeSat’ company. As the market leader, NanoRacks has deployed 61 CubeSats, with over 170 in the future pipeline. NanoRacks shows everyday that the promise of ISS utilization is being realized now.
NanoRacks External Payloads Manager, Kirk Woellert, added: “We are beyond thrilled to see the NRCSD back in action after on-orbit repairs. Every single CubeSat from this round of deployments has made contact with ground control, and we are celebrating side by side with our customers.”
NanoRacks Chief Technology Officer Michael D. Johnson concludes that “Space is now more agile, affordable, accessible, and we are using innovative technology to make efficient ISS services.”
NanoRacks LLC was formed in 2009 to provide commercial hardware and services for the U.S. National Laboratory onboard the International Space Station via a Space Act Agreement with NASA. NanoRacks’ main office is in Houston, Texas, right alongside the NASA Johnson Space Center. The Business Development office is in Washington, DC., and NanoRacks’ now has a new office in Silicon Valley, California. The Company has grown into the Operating System for Space Utilization by having the tools, the hardware and the services to allow other companies, organizations and governments to realize their own space plans.
To date over 200 payloads have been deployed by the Company on the International Space Station and our customer base includes the European Space Agency (ESA) the German Space Agency (DLR), NASA, US Government Agencies, Planet Labs, Urthecast, Space Florida, NCESSE, Virgin Galactic, pharmaceutical drug companies, and organizations in Vietnam, UK, Romania and Israel. Our customer base has propelled NanoRacks into a leadership position in understanding the emerging commercial market for low-earth orbit utilization.
Credit: nanoracks.com
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Posted: 07 Mar 2015 12:02 PM PST
Images from a December 2013 observation of the comet C/2013 R1 (Lovejoy) reveal clear details about rapidly changing activity in that comet's plasma tail. To get this image, astronomers used Subaru Telescope's wide-field prime-focus Suprime-Cam to zero in on 0.8 million kilometers of the comet's plasma tail, which resulted in gaining precious knowledge regarding the extreme activity in that tail as the comet neared the Sun. Their results are reported this week in a paper in the March 2015 edition of the Astronomical Journal. Team of researchers from National Astronomical Observatory of Japan, Stony Brook University (The State University of New York) and Tsuru University reported highly resolved find details of this comet captured in B-band in 2013 (Subaru Telescope's Image Captures the Intricacy of Comet Lovejoy's Tail). They used I-band filter which includes H2O+ line emissions and the V-band filter which includes CO+ and H2O+ line emissions.
During the observations, the comet exhibited very rapid changes in its tail in the course of only 20 minutes. Such extreme short-term changes are the result of the comet's interactions with the solar wind, which consists of charged particles constantly sweeping out from the Sun. The reason for the rapidity of these changes is not well understood.
Dr. Jin Koda, the principal investigator of these nights, says "My research is on galaxies and cosmology, so I rarely observe comets. But Lovejoy was up in the sky after my targets were gone on our observing nights, and we started taking images for educational and outreach purposes. The single image from the previous night revealed such delicate details along the tail it inspired us further to take a series of images on the following night. As we analyzed the images, we realized that the tail was displaying rapid motion in a matter of only a few minutes! It was just incredible!"
The plasma tail of a comet forms when gas molecules and atoms coming out from the comet encounter the solar wind. Changes and disturbances in the solar wind can affect the behavior and appearance of this plasma tail, causing it to form clumps of ionized material. The material in the plasma tail departs from the comet's coma and floats away on the solar wind. At these times, the plasma tail can take on a "kinked" or twisted look.
A good candidate for a detailed study of activity in the plasma tail must be a bright comet with an orbit that takes it close enough to the Sun to form such a tail. In addition, the best viewing angles for astronomers to capture views of plasma tail changes occur when the comet also approaches close to Earth. As a result, comets that allow good viewing of the plasma tail are relatively rare - about one or two per year. During its passage, Comet Lovejoy's plasma tail was almost perpendicular (83.5 degrees) to the line of sight from Earth. That made it a prime candidate for close-up observations of its plasma tail structure using Suprime-Cam.
Another discovery is that clumps located in the plasma tail at about 300 thousand kilometers from the nucleus moved at a fairly slow speed -- about 20 - 25 kilometers per second. That is much slower than reported in other comets, such as P/Halley, which gave off clumps that moved as fast as 58 kilometers per second or the value 44 +/- 11 kilometers per second as derived from several bright comets in the past.
The speed of the solar wind ranges from 300 to 700 kilometers per second and the wind intensity and velocity that the comet encounters depends on where it is located with respect to the Sun. The solar wind helps to accelerate the clumps in the tail out away from the Sun. Eventually the clumps in the comet's tail reach this high speed. The observation team thinks they witnessed the beginning of the acceleration of the clumps by the solar wind.
It is still under study how these ion clumps form and what parameters determine the initial speed of them. Dr. Masafumi Yagi, the first author of the paper noted "Comets are often observable only during the twilight as they come near the Sun. On the other hand, it becomes difficult to observe faint objects like galaxies during the twilight hours because of the brighter sky background. Well-designed telescope scheduling like this case makes an effective use of the Subaru Telescope's time and will enable us to collect more data of comets when the opportunity arises in the future."
The team's research paper titled “Initial Speed of Knots in the Plasma Tail of C/2013 R1 (Lovejoy) is published in Astronomical Journal in its March 2015 issue.
Credit: subarutelescope.org
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