Archive for the ‘Space News’ Category
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January 3rd, 2017
New White House document deals with the threat of Near Earth Objects (NEOs).
Credit: NASA
The White House has released a National Near-Earth Object Preparedness Strategy – a document developed by the Interagency Working Group (IWG) for Detecting and Mitigating the Impact of Earth-bound Near-Earth Objects (NEOs) (DAMIEN).
According to the strategy document it “seeks to improve our Nation’s preparedness to address the hazard of near-Earth object (NEO) impacts by enhancing the integration of existing national and international assets and adding important capabilities that are currently lacking.”
The Strategy builds on efforts at the National Aeronautics and Space Administration (NASA) to better detect and characterize the NEO population as well as recent efforts at the Department of Homeland Security (DHS) to prepare for and respond to a NEO impact.
Credit: OSTP
The document was published by White House Office of Science and Technology Policy.
Seven strategic goals
As detailed in the strategy, there are seven strategic goals that underpin the effort to enhance the Nation’s preparedness to NEO impacts:
Enhance NEO Detection, Tracking, and Characterization Capabilities. Objectives include: developing a capability roadmap to inform a strategy for investing in both U.S. and foreign abilities for detection, tracking, and characterization; improving observation capabilities for more complete and rapid observation of the entire population of NEOs; and updating existing observatories with capabilities to improve characterization assessments.
Develop Methods for NEO Deflection and Disruption. Objectives include: developing capabilities for fast-response focused reconnaissance and characterization; researching deflection and disruption capabilities for NEOs of varying size, mass, composition, and impact warning times; and researching technologies required for deflection and disruption concepts.
Improve Modeling, Predictions, and Information Integration. Objectives include: ensuring that adequate modeling capabilities are developed for each topical need, especially for modeling NEO trajectories to reduce orbit uncertainties and predicted impact effects; determining what outputs are required by whom; and establishing an organizational construct to coordinate the development and dissemination of modeling results.
Develop Emergency Procedures for NEO Impact Scenarios. Objectives include: promoting a collaborative national approach to defend against, mitigate, respond to, and recover from a NEO impact event; and developing coherent national and international communication strategies to facilitate NEO impact preparations.
Establish NEO Impact Response and Recovery Procedures. Objectives include: establishing national and international protocols to efficiently respond to a NEO impact, whether in deep ocean, coastal regions, or on land; and facilitating international cooperation and planning to recover from a NEO impact in a timely manner with minimal disruption.
Leverage and Support International Cooperation. Objectives include: building international support and policies for acknowledging and addressing the potential Earth impact of a NEO as a global challenge; fostering consultation, coordination, and cooperation channels and efforts for the planning for, impact emergency preparedness before, and response to a NEO impact; increasing engagement with the international community on observation infrastructure, data sharing, numerical modeling, and scientific research; strengthening international coordination and cooperation on NEO data and National Near-Earth Object Preparedness Strategy analyses; and promoting a collaborative international approach to preparedness for NEO events.
Establish Coordination and Communications Protocols and Thresholds for Taking Action. Objectives include: coordinating the communication of detected impact threats within the U.S. Government, as well as with other governments, media, and the public; developing a set of thresholds to aid U.S. decisions in whether to implement deflection or disruption missions; developing decision flowcharts for NEO hazard scenarios incorporating bench-marks and decision thresholds; and developing protocols for international interactions regarding NEO impacts outside of U.S. territory.
These seven high-level goals and associated objectives outlined in the Strategy are intended to support a collaborative and Federally-coordinated approach to developing effective policies, practices, and procedures for decreasing the Nation’s vulnerabilities associated with the NEO impact hazard.
Credit: OSTP
Significant and complex challenge
In a concluded statement, the Strategy document notes that, as with other low-probability, high-consequence hazards “potential NEO impacts pose a significant and complex challenge.”
The Strategy is seen as “a step in addressing the myriad challenges of managing and reducing the risks posed by both large and small NEOs.”
To read the full document, National Near-Earth Object Preparedness Strategy, go to:
Posted in 
Credit: CCTV-Plus
The first Moon-sample return to Earth mission in over four decades is being readied for launch by China.
Chinese engineers are completing work on the Chang’e-5 lunar mission for a launch later this year. If successful, this robotic spacecraft would attempt the first lunar sample return to Earth in over 40 years.
Historical notes
The former Soviet Union successfully executed three robotic sample return missions: Luna 16 returned a small sample (101 grams) from Mare Fecunditatis in September of 1970; February 1972, Luna 20 returned 55 grams of soil from the Apollonius highlands region; Luna 24 retrieved 170.1 grams of lunar samples from the Moon’s Mare Crisium (Sea of Crisis) for return to Earth in August 1976.
Ascender
According to Chinese news services, Chang’e-5 is comprised of four parts including the orbiter, ascender, lander, and Earth reentry module.
China’s Chang’e 3 Moon lander, imaged by Yutu lunar rover.
“The lander and ascender form a combination that will land on the Moon to conduct unmanned sample collection mission,” said Ruan Jianhua, deputy chief designer of China’s Chang’e-5. The lunar samples will be shot back to the Earth contained within the mission’s reentry module.
“We will later conduct research of Mars and other asteroids. We expect to go further in the exploration of deep space,” said Ruan via a CCTV-Plus interview.
Endless exploration
The first stage of China’s lunar expedition program was achieved by sending Chang’e 1, a circumlunar satellite, in 2007. China landed its first lunar probe Chang’e 3 on the surface of the moon in 2013.
China’s robotic circumlunar test flight snapped this image of the Moon with Earth in the distance.
Credit: Chinese Academy of Sciences
Last year, Tian Yulong, chief engineer of the State Administration of Science, Technology and Industry for National Defense (SASTIND) noted that “lunar exploration is endless.”
Tian said the Chang’e 5 is headed for finishing the third step of “going around, landing and returning.”
“But it doesn’t mean the exploration will cease,” Tian said.
Far side next
Space officials in China are also planning to be the first country to land on the far side of the Moon.
That mission is to be carried out by Chang’e-4, a backup for China’s Chang’e-3 spacecraft, and is due for launch in 2018.
“Our exploration has purposes and goals,” Tian said.
Following a circumlunar voyage in 2014, a return capsule parachuted to Earth. This test was a prelude to China’s Chang’e-5 lunar mission being readied for its return sample mission later this year.
Courtesy: China Space
Long-term path
According to Tian: “We have preliminarily conducted the demonstration of medium-to-long term development path of the Moon-probing system and also proposed to carry out a series of activities with distinctive features including the exploration of the Moon’s north and south poles after special tasks are completed.”
Tian said that China is in discussion with the European Space Agency and other countries “to build bases and carry out scientific investigations on the Moon, which will lay a technology and material foundation for human beings’ landing on the Moon in the future.”
For a behind-the-scenes look at getting China’s Chang’e-5 ready for its lunar mission, go to this CCTV-Plus video:
http://cd-pv.news.cctvplus.com/2016/1231/8039831_Preview_1806.mp4
Credit: NASA
This week there’s an impressive gathering of astronomers at the 229th meeting of the American Astronomical Society (AAS). The celestial confab is taking place January 3-7 in Grapevine, Texas.
Along with a host of papers and speakers is a special AAS session on “Geoengineering the Atmosphere to Fight Climate Change: Should Astronomers Worry about It?”
Growing concern
The session is hosted by the AAS Sustainability Committee on the issue that may be of growing concern to astronomers.
As defined by the committee, “geoengineering” — or large-scale engineering plans to modify the atmosphere in an attempt to offset the effects of global warming, such as by injecting aerosols globally to reflect sunlight.
Credit: AAS Sustainability Committee
Several researchers studying geoengineering, including astronomers, will present widely divergent views on the merits and risks of geoengineering and other climate interventions, both for ground-based astronomy, which of course must gaze through the atmosphere, and for the long-term stability of the Earth’s climate system.
Environmental impact
The mission of the AAS Sustainability Committee is “to inform and support AAS members in matters relating to the environmental impact of our work and provide facts, information and recommendations to its members for engaging in dialogue with students, colleagues and the broader world community.”
For more information on the overall AAS meeting, go to:
https://aas.org/meetings/aas229
For additional information on the AAS Sustainability Committee, go to:
Features called recurring slope lineae (RSL) have been spotted on some Martian slopes in warmer months. Some scientists think RSL could be seasonal flows of salty water. Red arrows point out one 0.75-mile-long (2 kilometers) RSL in this image taken by NASA’s Mars Reconnaissance Orbiter.
Credit: NASA/JPL-Caltech/Univ. of Arizona
A major Mars finding in recent years has been discovery of recurring slope lineae in certain areas of the Red Planet. These dark fingers of mystery – RSL in Mars shorthand — emerge from steep, rocky exposures. They incrementally grow, fade, and reform on a seasonal basis.
What RSL truly represent is debatable, but some researchers say they are suggestive that liquid water occurs on or near the surface of Mars today.
Question: Do RSL make noise?
Listen up
NASA’s 2020 Mars rover is to carry special cameras and microphones to capture stunning views and sounds, and not just its barnstorming entry and descent toward the Red Planet.
If the robot achieves a safe touchdown, the rover’s onboard microphones could put an ear to Mars, adding to the ambience of exploration.
The listening robot. New computer generated image of Mars 2020 rover.
Credit: NASA/JPL/Caltech
The future rover’s landing site has yet to be chosen…and given the gift of hearing, just what could its microphones pick up?
In an interview I did last year with Matthew Wallace, Mars 2020 rover deputy project manager at NASA’s Jet Propulsion Laboratory in Pasadena, California, he said the sounds of rover wheels trekking across the planet, the drill drilling, and rover’s mast moving are likely to be heard. High-speed wind bursts too.
From a distance
Any hope of hearing RSL?
“Probably not much…like grain flows, maybe some faint hissing or popping sounds?”
That’s the response from Alfred McEwen, a planetary geologist and director of the Planetary Image Research Laboratory at the University of Arizona in Tucson. He is the principal investigator of the High Resolution Imaging Science Experiment (HiRISE) for NASA’s Mars Reconnaissance Orbiter.
HiRISE has been the major tool in stimulating an “outpouring” of interest in RSL.
While HiRISE observations of RSL have been interpreted as present-day, seasonally variable liquid water flows, Mars-orbiting spectroscopy of the features has not confirmed the presence of liquid water, only hydrated salts.
Candidate RSL near the potential SW Melas Mars 2020 rover landing site – one of eight now under review.
Credit: D.E. Stillman et al.
Planetary protection
Whatever they are, say a rover is safely positioned near RSL activity, what’s the chance of hearing and seeing RSL in action?
Such a circumstance is moot as a rover won’t go near any candidate RSL due to NASA planetary protection rules. Where there is water, so too there may be microbial life.
“They probably make a little bit of noise, but the Mars 2020 probably could not hear it as it would be too far away,” said David Stillman, senior research scientist at the Southwest Research Institute in Boulder, Colorado.
Atmospherics
Adds John Rummel, a senior scientist at the SETI Institute with a distinguished track record in astrobiology and planetary protection issues:
“My guess is that you could get noise produced by a group of RSL,” Rummel said, “much the way that you can hear water running under a group of aspen in a small copse in the mountains in spring, even though it is hard to identify exactly where the noise is coming from.”
A copse is a thicket of bushes or a small stand of trees.
NASA Mars Reconnaissance Orbiter’s HiRISE image of recurring slope lineae in Melas Chasma, Valles Marineris. Arrows point out tops and bottoms of a few lineae.
Credit: NASA/JPL-Caltech/University of Arizona
But how far that noise could be received with such a small amount of atmosphere on Mars, “remains to be heard,” Rummel told Inside Outer Space.
“I would guess that you wouldn’t hear anything much, even if the noise were being produced right next to you. There is just not enough atmosphere to carry the sound,” Rummel added. “Sales figures for picnic boom-boxes on Mars will be slow, at first!”
All ears, eyes
For more information on how the Mars robot will be “all ears and eyes,” go to my Space.com story:
Mic’d Up on Mars! 2020 Rover Will Capture Sounds of Red Planet
August 4, 2016 07:00am ET
http://www.space.com/33637-nasa-mars-2020-rover-microphone.html
Curiosity Front Hazcam Left B image taken on Sol 1566, January 1, 2017.
Credit: NASA/JPL-Caltech
NASA’s Curiosity Mars rover is nearing Sol 1567, landing on the planet in August 2012.
As the robot wheels toward its fifth year of operations on the Red Planet in 2017, the rover is finding patterns of change in rock composition at higher, younger layers of a mountain.
Curiosity Navcam Left B image taken on Sol 1566, January 1, 2017.
Credit: NASA/JPL-Caltech
A factor favorable for possible life, Curiosity has surveyed ancient Mars sedimentary basins with groundwater finding them chemically active.
Late in 2016, scientists reported that Curiosity has found boron on Mars, a first for this very soluble element. Boron has ended up in calcium sulfate veins found within mudstone layers of the Murray formation on Mars’ lower Mount Sharp.
Image Credit: NASA/JPL-CALTECH
Curiosity ChemCam Remote Micro-Imager photo taken on Sol 1566, January 1, 2017.
Credit: NASA/JPL-Caltech/LANL
Curiosity Rear Hazcam Left B image acquired on Sol 1566, December, 31, 2016.
Credit: NASA/JPL-Caltech
Types of satellites based on mass, compared to Earth-bound objects.
Credit: CRS
A fact-filled new Congressional Research Service (CRS) report spotlights today’s status of the commercial space industry.
The report — Commercial Space Industry Launches a New Phase – is authored by Bill Canis, a CRS specialist in industrial organization and business.
Changing face
This document explains that the face of the U.S. space industry is changing with a government shift toward use of fixed price contracts for commercial services, new entrants with new launch products, and an increase in the use of smaller satellites.
NASA’s commercial cargo program and other federal contracts are supporting the growth of the commercial launch industry, with less expensive rockets, some of which are planned to be reusable. Many of the new space-related companies are attracting rising levels of venture capital.
Aggressive pricing by U.S. entrants is cutting into the international launch market once dominated by foreign providers.
A renewed interest in low-cost satellites, some of which are small enough to be held in one hand, is prompting a range of start-ups and providing new accessibility to space by educational institutions, small businesses, and individual researchers.
Factoids
Flagged in the report are these factoids: At the end of June 2016, 1,419 satellites were in operation, with 55% in low Earth orbit, 36% in geosynchronous orbit, 7% in middle Earth orbit, and the remainder in high Earth orbit.
Credit: CRS
Of these, 576 are U.S. satellites, 140 Russian, 181 Chinese, and 522 from other countries.
Of the U.S. satellites, 286 are commercial, 146 military, 132 government, and 12 civil.
Policy issues
In terms of policy issues for Congress, the CRS report concludes that there are three overarching issues will affect the development of commercial space in the future.
- how the industry is regulated by diverse federal agencies
- the effects of new export control laws and regulations that seek to increase U.S. space industry competitiveness
- the allocation of spectrum for satellite use
Resource
The CRS report — Commercial Space Industry Launches a New Phase – is available here:
Credit: White House/Souza
As the administration of President-elect Donald Trump kicks into high-gear, just how the country’s civil and military space agenda will be treated is on the table. For space advocates is there a move on to burst the Washington, D.C. space bubble?
Late in the 2016 Trump campaign, the idea of re-launching a National Space Council was aired. To be established within the Executive Office of the President of the United States, this organization would likely be chaired by Vice President-elect Mike Pence.
What’s ahead for this idea?
Take a look at my new Space.com story at:
Playing the Space Trump Card: Relaunching a National Space Council
December 29, 2016 12:00pm ET
http://www.space.com/35163-trump-administration-national-space-council.html
Credit: gov.cn
China’s Information Office of the State Council on December 27 released an expansive white paper on that country’s space activities in 2016, and projected looks at its space agenda in coming years.
In an associated press conference marking the release of the white paper, vice administrator of the China National Space Administration, Wu Yanhua, stated that China plans to develop a new generation of heavy-lift carrier rocket, the “Changzheng-9” or “Long March-9.”
That booster is intended for future manned lunar landing and deep space exploration missions, according to a report by CRIENGLISH.com.
Vice administrator of China National Space Administration, Wu Yanhua, speaks at Dec. 27 briefing unveiling a white paper on Chinese space development 2016.
Credit: gov.cn
Wu said during the press conference: “There is an old saying in aerospace industry, ‘If you want to develop space industry, you need to work on space rockets first; and if you want to develop space rockets, you need to work on its engines first’. So now we need to make progress in the heavy-lift carrier rocket’s engine first, to create conditions for the whole project. It is planned that the heavy-lift carrier rocket’s maiden flight will be held around 2030.”
Wide-ranging white paper
In the wide-ranging white paper, China’s space program purposes, vision and principles of development are spotlighted, including major developments since 2011, as well as major tasks for the next five years.
The document also includes policies and measures for development and the role of international exchanges and cooperation.
In terms of deep-space exploration, the white paper explains that China will continue its lunar exploration project, and strive to attain the automated extraterrestrial sampling and returning technology by space explorers.
China’s Moon program intends to support a lunar sample return in 2017.
Credit: Chinese Academy of Sciences
Three strategic steps
“We plan to fulfill the three strategic steps of ‘orbiting, landing and returning’ for the lunar exploration project by launching the Chang’ e-5 lunar probe by the end of 2017 and realizing regional soft landing, sampling and return. We will launch the Chang’e-4 lunar probe around 2018 to achieve mankind’s first soft landing on the far side of the moon, and conduct in situ and roving detection and relay communications at earth-moon L2 point.”
Also, noted is that through China’s lunar exploration project, topographic and geological surveys will be implemented and laboratory research conducted on lunar samples; geological survey and research as well as low-frequency radio astronomy observation and research will be carried out targeting the landing area on the far side of the Moon for a better understanding of the formation and evolution of the Moon.
A Chinese Service Module practiced steps needed for the Chang’e 5 mission, slated for 2017 – a multi-module spacecraft that would land, collect, and return to Earth lunar samples.
Credit: China Space Website
Next lunar probe
At the press conference hosted by the State Council Information Office, Wu also detailed work underway on Chang’e-5, targeted for liftoff at the end of 2017.
“We will take samples from the surface of the moon as well as different depths of the moon rocks after drilling, and the samples will be used by scientists for scientific research,” Wu said.
Wu added that work related to Chang’e-5 is going smoothly.
Mars and beyond
Explained in the white paper is that China intends to execute its first Mars exploration operation, and grasp key technologies for orbiting, landing and roving exploration.
China plans to launch this Mars probe by 2020 to carry out orbiting and roving exploration.
Credit: CCTV/China Spaceflight.com
“It will conduct further studies and key technological research on the bringing back of samples from Mars, asteroid exploration, exploration of the Jupiter system and planet fly-by exploration. When conditions allow, related projects will be implemented to conduct research into major scientific questions such as the origin and evolution of the solar system, and search for extraterrestrial life,” the paper explains.
Raising human spaceflight capacity
In the category of human spaceflight, the white paper notes that China plans to launch the Tianzhou-1 cargo spacecraft to dock with the now Earth-orbiting Tiangong-2 space laboratory, “and research and master key technologies for cargo transport and replenishment to accumulate experience in building and operating a space station.”
“We strive to acquire key technologies and conduct experiments on such technologies,” the paper continues, “to raise our manned spaceflight capacity, laying a foundation for exploring and developing cislunar space.”
China’s 60-ton medium-size space station is depicted in this artwork.
Credit: CNSA
Launch site network
In June 2016 the Wenchang Launch Site held its first launch, marking a new-generation launch site designed and built by China. Renovations have also been accomplished in the Jiuquan, Taiyuan and Xichang launch sites, “forming a launch site network covering both coastal and inland areas, high and low altitudes, and various trajectories to satisfy the launch needs of manned spaceships, space laboratory core modules, deep space probes and all kinds of satellites,” the document explains. “The integrated capacities and functions of space launch sites will be enhanced and exploited to meet various needs.”
Historical starting line
The white paper concludes by noting that the country is “standing at a new historical starting line,” with China “determined to quicken the pace of developing its space industry, and actively carry out international space exchanges and cooperation.”
Since 2011 China has signed 43 space cooperation agreements or memoranda of understanding with 29 countries, space agencies and international organizations.
For the full, multi-part white paper — China’s Space Activities in 2016 — go to:
http://www.globaltimes.cn/content/1025885.shtml
To view CCTV-Plus videos of the press event and release of the white paper, go to:
http://pv.news.cctvplus.com/2016/1227/8039508_Preview_3124.mp4
http://pv.news.cctvplus.com/2016/1227/8039556_Preview_1482843796001.mp4
Credit: Aeon
When we look for aliens, why do we always find ourselves staring back?
Narrated by the British science writer Philip Ball, an Aeon original video argues that, in order to stand a chance of succeeding, the modern scientific search for aliens needs to ditch science fiction’s frequently simplistic and solipsistic views in favor of a truly bold approach to imagining extraterrestrial life.
Human-inflected conception
Humans have long imagined beings in other worlds or on other planets whose emotions, motivations and physiologies closely mirror our own. Science fiction in its many forms tends toward a human-inflected conception of non-human life out in the Universe.
Graphic above by Danielle Futselaar is the famous Drake Equation, representing the full spectrum of science undertaken at the SETI Institute. Wherever you are on Earth, the Drake Equation represents all explorations of our lives, and life beyond our home planet.
Credit: Danielle Futselaar/SETI Institute
The view of aliens as rather like us is fine for ancient myths and Hollywood blockbusters, but even modern scientists can’t seem to shake the notion that extraterrestrials’ decisions and behavior would follow logic and patterns akin to our own.
Many of the major scientific projects seeking life elsewhere in the cosmos still rely on assumptions that reflect, above all, ideas about how we would do something if we were aliens.
To view this thought-provoking video, go to:
Space Traffic Management – New Report Calls for Civil Government Agency to Deal with Orbital Clutter
Credit: SAIC
A recently released report has taken a hard look at “traffic management” of the space domain – an environment increasingly cluttered by orbiting space debris.
The study – Orbital Traffic Management Study: Final Report – Report on Space Traffic Management Assessments, Frameworks and Recommendations was issued November 21 by Science Applications International Corporation (SAIC).
The report was done for NASA as required by the Commercial Space Launch Competitiveness Act.
Current framework
As noted by Marcia Smith’s SpacePolicyOnline.com: “SAIC is recommending that a civil government agency take responsibility for orbital traffic management, but it does not specify which agency that should be.”
Clutter in the cosmos.
Credit: Used with permission: Melrae Pictures/Space Junk 3D
Smith explains that the Federal Aviation Administration (FAA) and its parent, the Department of Transportation (DOT), are often the center of attention in orbital — or space — traffic management discussions, but SAIC explained that the terms of reference for its study did not ask for such a recommendation.
“SAIC concluded that the current framework — where DOD [Department of Defense] tracks space objects and provides conjunction analyses to other U.S. government as well as commercial and foreign entities — is insufficient and a ‘holistic approach’ is needed, led by a civil government agency,” SpacePolicyOnline.com observes.
In the report, no assumptions or recommendations are made as to which specific civil agency could or should be designated – such a recommendation was not specified by Congress as a report product.
Alternate frameworks
Smith notes that the study lays out five alternative frameworks:
- Private space traffic monitoring and coordination,
- DOD-based space traffic safety monitoring and data sharing (status quo),
- Civil-based space traffic safety monitoring and facilitation
- Civil-based space traffic safety monitoring and coordination
- Civil-based space traffic management.
It compares them in terms of three objectives:
- Ensure safety of the space domain
- Protect and enhance national security space interests
- Ensure the economic vitality of the space domain and space industrial base
Organizational evolution
One author of the report, David Finkleman of SkySentry, LLC, told Inside Outer Space that the space traffic management (STM) study recommends an “organizational evolution” for STM.
“This was the charge from Congress. It recognizes that STM is global, not achievable by the U.S. alone. Any satellite owner or operator who declines collaboration is a threat to all and is himself at risk,” Finkleman explains.
“The state of satellite traffic is a serious environmental concern but not a catastrophe,” Finkleman notes.
“Action recommended by the STM report will make catastrophe much less likely,” adding that this is his personal opinion, not the position of SAIC, NASA, the U.S. Government, or any organization with a stake in STM.
International problem
Similar in view, and another author of the SAIC report, is Theresa Hitchens of the Center for International and Security Studies at Maryland at the University of Maryland in College Park. “This is an international problem, and requires an international solution. A U.S. system must be coordinated with other space-faring and space-using nations,” Hitchens told Inside Outer Space.
“This also means that however a U.S. civil agency is designed,” Hitchens advised, “it must be able to relatively freely share orbital positioning data with other nations, as well as integrate data from outside the U.S. military. That is…Space Situational Awareness (SSA) must become multi-stakeholder. Otherwise, a U.S. civil agency on top of a U.S. military controlled data pool becomes only another layer of bureaucracy that industry must pass through, and does nothing much to improve the space traffic situation,” she said, also noting her views are her own, not on behalf of SAIC or NASA.
Orbital debris is a space environmental problem.
Credit: Lockheed Martin
Trackable space objects
The nearly 120-page SAIC report offers a number of interesting perspectives, such as spotlighting the likelihood of space traffic safety incidents. It is predicted that about one collision will occur per year between tracked non-maneuvering space objects and debris greater than one centime-size in the low Earth orbit (LEO) region.
The overwhelming majority of trackable space objects are categorized as orbital debris, states the SAIC study.
“Of the approximately 23,000 cataloged space objects (all greater in size than 10 cm), only about six percent are (operational) spacecraft. A little more than about one quarter of all (operational) spacecraft are U.S. private owned and operated. This is two percent of all cataloged space objects. Not all of the (U.S.) private spacecraft can be maneuvered propulsively (especially CubeSats).”
Credit: SAIC
Star-crossed constellations
The report notes that some proposed new large constellations of small satellites could add thousands more spacecraft to the space catalog over a few years. Also, it is estimated that once the new “Space Fence” satellite situational awareness radar system becomes operational, the number of space objects in the space catalog could increase by approximately 60,000.
“This estimated increase will add complexity to the current conjunction assessment process, although the additional burden may be offset by a beneficial reduction in space object orbit uncertainty used to determine probability of collisions,” the report explains.
As flagged in the report, “there are no explicit or implicit national or international–level requirements for space traffic management (STM) under treaties and other legally-binding international agreements, to which the United States is a party.”
In-orbit explosions can be related to the mixing of residual fuel that remain in tanks or fuel lines once a rocket stage or satellite is discarded in Earth orbit. The resulting explosion can destroy the object and spread its mass across numerous fragments with a wide spectrum of masses and imparted speeds.
Credit: ESA
Debris-producing events
The SAIC study compiled a list of the top worst debris-producing events, noting:
- The Iridium/Cosmos collision is the only debris-producing incident on the list known to be caused by an unintentional collision.
- The China anti-satellite (ASAT) test of 2007 ranks as the event causing the largest number of pieces of debris.
- Six of the remaining seven events on the compiled list were the result of orbital breakup (explosions), and in the remaining incident, the cause is unknown.
- The likelihood of orbital breakup is very much a function of the spacecraft design features and the physical behavior of the satellite’s systems that contain energy (propellant tanks, pressurant tanks, batteries, and momentum wheels). The recent orbital breakups of three DOD Defense Meteorological Satellite Program (DMSP) satellites caused by battery-associated events are a good example of such debris generating events (this satellite series was designed and approved before orbital debris mitigation requirements were established in the United States).
- A recent example of an orbital breakup that was somewhat unusual is Japan’s Hitomi X-ray observatory. Because of a design error, this satellite literally spun itself out of control with such a rate of rotation that it came apart.
Credit: SAIC
Space station concerns
The SAIC report includes a look at the International Space Station and the threat of orbital debris hits to the orbiting complex.
As debris populations grow in LEO, the odds of Micrometeoroids and Orbital Debris (MMOD) root cause events on ISS will become higher (i.e. worsen); but, the SAIC study did not find any analysis that quantified this increased risk.
Chunk of junk zips by the International Space Station.
Credit: NASA
Recent analysis by the Aerospace Corporation on new large LEO constellations, the SAIC study observes, found that such constellations could increase the number of collision warnings with ISS six-fold, for example, as the decommissioned spacecraft in those constellations decay through the ISS orbit. This result does not correspond to a direct increase in the odds of a MM/OD root cause event, “but does show that risk can go up,” the SAIC report explains.
Resources
To access the SAIC report on Space Traffic Management Assessments, Frameworks and Recommendations, go to:
For the informative review of the study by Marcia Smith’s SpacePolicyOnline.com, go to:
