sexta-feira, 31 de janeiro de 2014
“If true, the stirring provided by migrating planets may have been essential to bringing those asteroids,” the astronomers stated in a press release. “This raises the question of whether an Earth-like exoplanet would also require a rain of asteroids to bring water and make it habitable. If so, then Earth-like worlds might be rarer than we thought.”
To take this example further, the researchers found that the asteroid belt comes from a mix of locations around the solar system. Well, a model the astronomers cite shows that Jupiter once migrated much closer to the sun, basically at the same distance as where Mars is now.
When Jupiter migrated, it disturbed everything in its wake and possibly removed as much as 99.9 per cent of the original asteroid population. And other planet migrations in general threw in rocks from everywhere into the asteroid belt. This means the origin of water in the belt could be more complicated than previously believed.
You can read more details of the survey in the journal Nature. Data was gathered from the Sloan Digital Sky Survey and the research was led by Francesca DeMeo, a Hubble postdoctoral fellow at the Harvard-Smithsonian Center for Astrophysics.
Read more: http://www.universetoday.com/108762/earths-water-story-gets-a-plot-twist-from-space-rock-search/#ixzz2s0vBTTzi
This equivalence between floating and falling is what Einstein used to develop his theory. In general relativity, gravity is not a force between masses. Instead gravity is an effect of the warping of space and time in the presence of mass. Without a force acting upon it, an object will move in a straight line. If you draw a line on a sheet of paper, and then twist or bend the paper, the line will no longer appear straight. In the same way, the straight path of an object is bent when space and time is bent. This explains why all objects fall at the same rate. The gravity warps spacetime in a particular way, so the straight paths of all objects are bent in the same way near the Earth.
So what kind of experiment could possibly prove that gravity is warped spacetime? One stems from the fact that light can be deflected by a nearby mass. It is often argued that since light has no mass, it shouldn’t be deflected by the gravitational force of a body. This isn’t quite correct. Since light has energy, and by special relativity mass and energy are equivalent, Newton’s gravitational theory predicts that light would be deflected slightly by a nearby mass. The difference is that general relativity predicts it will be deflected twice as much.
The effect was first observed by Arthur Eddington in 1919. Eddington traveled to the island of Principe off the coast of West Africa to photograph a total eclipse. He had taken photos of the same region of the sky sometime earlier. By comparing the eclipse photos and the earlier photos of the same sky, Eddington was able to show the apparent position of stars shifted when the Sun was near. The amount of deflection agreed with Einstein, and not Newton. Since then we’ve seen a similar effect where the light of distant quasars and galaxies are deflected by closer masses. It is often referred to as gravitational lensing, and it has been used to measure the masses of galaxies, and even see the effects of dark matter.
Another piece of evidence is known as the time-delay experiment. The mass of the Sun warps space near it, therefore light passing near the Sun is doesn’t travel in a perfectly straight line. Instead it travels along a slightly curved path that is a bit longer. This means light from a planet on the other side of the solar system from Earth reaches us a tiny bit later than we would otherwise expect. The first measurement of this time delay was in the late 1960s by Irwin Shapiro. Radio signals were bounced off Venus from Earth when the two planets were almost on opposite sides of the sun. The measured delay of the signals’ round trip was about 200 microseconds, just as predicted by general relativity. This effect is now known as the Shapiro time delay, and it means the average speed of light (as determined by the travel time) is slightly slower than the (always constant) instantaneous speed of light.
Read more: http://www.universetoday.com/108740/how-we-know-gravity-is-not-just-a-force/#ixzz2s0tuaUiV
A third effect is gravitational waves. If stars warp space around them, then the motion of stars in a binary system should create ripples in spacetime, similar to the way swirling your finger in water can create ripples on the water’s surface. As the gravity waves radiate away from the stars, they take away some of the energy from the binary system. This means that the two stars gradually move closer together, an effect known as inspiralling. As the two stars inspiral, their orbital period gets shorter because their orbits are getting smaller.
For regular binary stars this effect is so small that we can’t observe it. However in 1974 two astronomers (Hulse and Taylor) discovered an interesting pulsar. Pulsars are rapidly rotating neutron stars that happen to radiate radio pulses in our direction. The pulse rate of pulsars are typically very, very regular. Hulse and Taylor noticed that this particular pulsar’s rate would speed up slightly then slow down slightly at a regular rate. They showed that this variation was due to the motion of the pulsar as it orbited a star. They were able to determine the orbital motion of the pulsar very precisely, calculating its orbital period to within a fraction of a second. As they observed their pulsar over the years, they noticed its orbital period was gradually getting shorter. The pulsar is inspiralling due to the radiation of gravity waves, just as predicted.
Finally there is an effect known as frame dragging. We have seen this effect near Earth itself. Because the Earth is rotating, it not only curves spacetime by its mass, it twists spacetime around it due to its rotation. This twisting of spacetime is known as frame dragging. The effect is not very big near the Earth, but it can be measured through the Lense-Thirring effect. Basically you put a spherical gyroscope in orbit, and see if its axis of rotation changes. If there is no frame dragging, then the orientation of the gyroscope shouldn’t change. If there is frame dragging, then the spiral twist of space and time will cause the gyroscope to precess, and its orientation will slowly change over time.
We’ve actually done this experiment with a satellite known as Gravity Probe B, and you can see the results in the figure here. As you can see, they agree very well.
Each of these experiments show that gravity is not simply a force between masses. Gravity is instead an effect of space and time. Gravity is built into the very shape of the universe.
Think on that the next time you step onto a scale.
Read more: http://www.universetoday.com/108740/how-we-know-gravity-is-not-just-a-force/#ixzz2s0uLKcd1
When we think of gravity, we typically think of it as a force between masses. When you step on a scale, for example, the number on the scale represents the pull of the Earth’s gravity on your mass, giving you weight. It is easy to imagine the gravitational force of the Sun holding the planets in their orbits, or the gravitational pull of a black hole. Forces are easy to understand as pushes and pulls.
But we now understand that gravity as a force is only part of a more complex phenomenon described the the theory of general relativity. While general relativity is an elegant theory, it’s a radical departure from the idea of gravity as a force. As Carl Sagan once said, “Extraordinary claims require extraordinary evidence,” and Einstein’s theory is a very extraordinary claim. But it turns out there are several extraordinary experiments that confirm the curvature of space and time.(...)
Read the rest of How We Know Gravity is Not (Just) a Force (1,197 words)
Read the rest of How We Know Gravity is Not (Just) a Force (1,197 words)
Posted: 30 Jan 2014 09:58 AM PST
The team operating NASA's Mars rover Curiosity is considering a path across a small sand dune to reach a favorable route to science destinations. A favorable route would skirt some terrain with sharp rocks considered more likely to poke holes in the rover's aluminum wheels. While the team has been assessing ways to reduce wear and tear to the wheels, Curiosity has made progress toward a next site for drilling a rock sample and also toward its long-term destination: geological layers exposed on slopes of Mount Sharp. The rover has driven into a mapping quadrant that includes a candidate site for drilling. Meanwhile, testing on Earth is validating capabilities for drilling into rocks on slopes the rover will likely encounter on Mount Sharp.
Curiosity has driven 865 feet (264.7 meters) since Jan. 1, for a total odometry of 3.04 miles (4.89 kilometers) since its August 2012 landing.
Accumulation of punctures and rips in the wheels accelerated in the fourth quarter of 2013. Among the responses to that development, the team now drives the rover with added precautions, thoroughly checks the condition of Curiosity's wheels frequently, and is evaluating routes and driving methods that could avoid some wheel damage.
|This stereo mosaic of images from the Navigation Camera (Navcam) on NASA's Mars rover Curiosity shows the terrain surrounding the rover's position on the 524th Martian day, or sol, of the mission (Jan. 26, 2014). Image Credit: NASA/JPL-Caltech|
A dune about 3 feet (1 meter) high spans the gap between two scarps that might be a gateway to a southwestward route over relatively smooth ground. Curiosity is approaching the site, "Dingo Gap," from the southeast. The team is using images from the rover to assess whether to cross the dune.
"The decision hasn't been made yet, but it is prudent to go check," said Jim Erickson of NASA's Jet Propulsion Laboratory, Pasadena, Calif., project manager for Curiosity. "We'll take a peek over the dune into the valley immediately to the west to see whether the terrain looks as good as the analysis of orbital images implies." The orbital images come from the High Resolution Imaging Science Experiment (HiRISE) camera on NASA's Mars Reconnaissance Orbiter.
|This map shows the route that NASA's Curiosity Mars rover drove inside Gale Crater from its landing in August 2013 through the 524th Martian day, or sol, of the mission (Jan. 26, 2014). Image Credit: NASA/JPL-Caltech/Univ. of Arizona|
Other routes have also been evaluated for getting Curiosity from the rover's current location to a candidate drilling site called "KMS-9." That site lies about half a mile (800 meters) away by straight line, but considerably farther by any of the driving routes assessed. Characteristics seen in orbital imagery of the site appeal to Curiosity's science team. "At KMS-9, we see three terrain types exposed and a relatively dust-free surface," said science team collaborator Katie Stack of the California Institute of Technology, Pasadena.
Before Curiosity's landing inside Gale Crater, the mission's science team used images from orbit to map terrain types in a grid of 140 square quadrants, each about 0.9 mile (1.5 kilometers) wide. Curiosity landed in the "Yellowknife" quadrant and subsequently crossed parts of quadrants called "Mawson" and "Coeymans." This month, it entered the "Kimberley" quadrant, home of KMS-9.
Stack said, "This area is appealing because we can see terrain units unlike any that Curiosity has visited so far. One unit has striations all oriented in a similar direction. Another is smooth, without striations. We don't know yet what they are. The big draw is exploration and seeing new things."
Science investigations have continued along with recent drives. One rock examined on Jan. 15, "Harrison," revealed linear crystals with feldspar-rich composition.
As NASA's Mars rover Curiosity is progressing toward Mount Sharp, researchers are using the rover's instruments to examine soils and rocks in Gale Crater. Image Credit: NASA/JPL Caltech/LANL/CNES/IRAP/LPGNantes/CNRS/IA
To prepare for destinations farther ahead, engineers are using a test rover at JPL to check the rover's ability to tolerate slight slippage on slopes while using its drill. With the drill bit in a rock, tests simulating slips of up to about 2 inches (5 centimeters) have not caused damage.
"These tests are building confidence for operations we are likely to use when Curiosity is on the slopes of Mount Sharp," said JPL's Daniel Limonadi, systems engineering leader for surface sampling with the rover's arm.
Other testing at JPL is evaluating possible driving techniques that might help reduce the rate of wheel punctures, such as driving backwards or using four-wheel drive instead of six-wheel drive. Some of the wheel damage may result from the force of rear wheels pushing middle or front wheels against sharp rocks, rather than simply the weight of the rover driving over the rocks.
"An analogy is when you are rolling your wheeled luggage over a curb, you can feel the difference between trying to push it over the curb or pull it over the curb," said JPL's Richard Rainen, mechanical engineering team leader for Curiosity.
While continuing to evaluate routes and driving techniques, Curiosity's team will add some weekend and evening shifts in February to enable planning more drives than would otherwise be possible.
Posted: 30 Jan 2014 10:24 AM PST
A storm of stars is brewing in the Trifid nebula, as seen in this view from NASA's Wide-field Infrared Survey Explorer, or WISE. The stellar nursery, where baby stars are bursting into being, is the yellow-and-orange object dominating the picture. Yellow bars in the nebula appear to cut a cavity into three sections, hence the name Trifid nebula. Colors in this image represent different wavelengths of infrared light detected by WISE. The main green cloud is made up of hydrogen gas. Within this cloud is the Trifid nebula, where radiation and winds from massive stars have blown a cavity into the surrounding dust and gas, and presumably triggered the birth of new generations of stars. Dust glows in infrared light, so the three lines that make up the Trifid, while appearing dark in visible-light views, are bright when seen by WISE.
The blue stars scattered around the picture are older, and they lie between Earth and the Trifid nebula. The baby stars in the Trifid will eventually look similar to those foreground stars. The red cloud at upper right is gas heated by a group of very young stars.
The Trifid nebula is located 5,400 light-years away in the constellation Sagittarius.
|Radiation and winds from massive stars have blown a cavity into the surrounding dust and gas, creating the Trifid nebula, as seen here in infrared light by NASA's Wide-field Infrared Survey Explorer, or WISE. Image credit: NASA/JPL-Caltech/UCLA|
Blue represents light emitted at 3.4-micron wavelengths, and cyan (blue-green) represents 4.6 microns, both of which come mainly from hot stars. Relatively cooler objects, such as the dust of the nebula, appear green and red. Green represents 12-micron light and red, 22-micron light.
NASA's Jet Propulsion Laboratory, Pasadena, Calif., manages and operates the recently activated NEOWISE asteroid-hunting mission for NASA's Science Mission Directorate. The results presented here are from the WISE all-sky survey mission, which operated before NEOWISE, using the same spacecraft, in 2010 and 2011. WISE was selected competitively under NASA's Explorers Program managed by the agency's Goddard Space Flight Center in Greenbelt, Md. The science instrument was built by the Space Dynamics Laboratory in Logan, Utah. The spacecraft was built by Ball Aerospace & Technologies Corp. in Boulder, Colo. Science operations and data processing take place at the Infrared Processing and Analysis Center at the California Institute of Technology, Pasadena. Caltech manages JPL for NASA.
Posted: 30 Jan 2014 12:05 PM PST
American astronauts will continue to fly to the International Space Station aboard Russian spacecraft through 2017, NASA said Wednesday. “Until a US commercial vehicle is sustained, continued access to Russian crew launch, return, and rescue services is essential for planned ISS operations,” NASA said in a procurement announcement. The agency intends to buy six more seats on Russian Soyuz spacecraft to ferry American astronauts to the ISS in 2017. NASA will also contract with the Russian space agency Roscosmos to have seats available on docked Soyuz craft through spring 2018 in the event of an emergency evacuation of the station.
The cost of the proposed deal was not disclosed, but NASA signed a contract with Roscosmos last spring to pay about $70 million per seat for launch services through early 2017.
The agency, which is funding the development of several manned spacecraft, plans to select a commercial launch provider for missions starting in 2017.
Two NASA-funded private spacecraft – SpaceX’s Dragon and Orbital Sciences Corp.’s Cygnus – have already made unmanned resupply missions to the ISS.
No American vehicle has taken astronauts into orbit since the decommissioning of NASA’s shuttle fleet in 2011. The Soyuz is one of only two operational orbital manned spacecraft in the world, the other being China’s Shenzhou.
Credit: RIA Novosti
Posted: 30 Jan 2014 12:33 PM PST
It has long puzzled scientists that there were enormously massive galaxies that were already old and no longer forming new stars in the very early universe, approx. 3 billion years after the Big Bang. Now new research from the Niels Bohr Institute in Copenhagen, Denmark, among others, shows that these massive galaxies were formed by explosive star formation that was set in motion by the collision of galaxies a few billion years after the Big Bang. The results are published in the scientific journal, Astrophysical Journal. Galaxies are giant collections of stars, gas and dark matter. The smallest galaxies contain a few million stars, while the largest can contain several hundred billion stars. The first stars already emerged in the very early universe approx. 200 million years after the Big Bang from the gases hydrogen and helium.
Gas is the raw material used to form stars. These giant clouds of gas and dust contract and eventually the gas is so compact that the pressure heats the matter so that glowing gas balls are formed, new stars are born. The stars are collected in galaxies, the first of which are a kind of baby galaxies. As long as there is gas in the galaxy, new stars are being formed.
Mysteries in the childhood of the universe
The astronomers’ theory is therefore that the structure of the universe was built by baby galaxies gradually growing larger and more massive by constantly forming new stars and by colliding with neighbouring galaxies to form new, larger galaxies. The largest galaxies in today’s universe were therefore believed to have been under construction throughout the history of the universe.
“That is why it surprised us that we already when the universe was only 3 billion years old, found galaxies that were just as massive as today’s large spiral galaxies and the largest elliptical galaxies, which are the giants in the local universe. Even more surprisingly, the stars in these early galaxies were squeezed into a very small area, so the size of the galaxies were three times smaller than similar mass galaxies today. This means that the density of stars was 10 times greater. Furthermore, the galaxies were already dead, so they were no longer forming new stars. It was a great mystery,” explains Sune Toft, Dark Cosmology Centre at the Niels Bohr Institute at the University of Copenhagen.
The extremely massive and compact galaxies were not flattened spiral galaxies where stars and gas rotate around the centre. Rather, they resembled elliptical galaxies where stars move more hither and thither and where the gas for new star formation has been used up. But how could the galaxies become so massive and so burnt out so early? How were they formed?
Solving the mystery
To find out what happened, Sune Toft had to look even further back in time. Based on the ages of the galaxies, he knew that they had to have formed very early in the history of the universe, but at that point there was simply not enough time for the galaxies to have grown so massive through normal star formation. He had a theory that the massive galaxies were formed by the fusion of smaller galaxies, but that alone could not explain how they had become so massive so quickly and were already dead. The theory was therefore, that there must have been some especially extreme galaxies in the formation process.
“We studied the galaxies that existed when the universe was between 1 and 2 billion years old. My theory that it must have been some galaxies with very specific properties that were part of the formation process made me focus on the special SMG galaxies, which are dominated by intense stare formation hidden under a thick blanket of dust,” explains Sune Toft.
He explains that when such gas-rich galaxies merge, all of the gas is driven into the centre of the system where it ignites an explosion of new star formation. A lot of stars are formed in the centre and the galaxy quickly becomes very compact. But with the explosive star formation, the gas to form new stars is also used up extremely quickly and then you get a dead galaxy.
“I discovered that there was a direct evolutionary link between two of the most extreme galaxy types we have in the universe – the most distant and most intense star forming galaxies which are formed shortly after the Big Bang – and the extremely compact dead galaxies we see 1-2 billion years later,” says Sune Toft. The new research is a breakthrough in discovering the formation process of the enormously massive and dead galaxies in the early universe.
Posted: 30 Jan 2014 01:14 PM PST
Our solar system seems like a neat and orderly place, with small, rocky worlds near the Sun and big, gaseous worlds farther out, all eight planets following orbital paths unchanged since they formed. However, the true history of the solar system is more riotous. Giant planets migrated in and out, tossing interplanetary flotsam and jetsam far and wide. New clues to this tumultuous past come from the asteroid belt. "We found that the giant planets shook up the asteroids like flakes in a snow globe," says lead author Francesca DeMeo, a Hubble postdoctoral fellow at the Harvard-Smithsonian Center for Astrophysics. Millions of asteroids circle the Sun between the orbits of Mars and Jupiter, in a region known as the main asteroid belt. Traditionally, they were viewed as the pieces of a failed planet that was prevented from forming by the influence of Jupiter's powerful gravity. Their compositions seemed to vary methodically from drier to wetter, due to the drop in temperature as you move away from the Sun.
That traditional view changed as astronomers recognized that the current residents of the main asteroid belt weren't all there from the start. In the early history of our solar system the giant planets ran amok, migrating inward and outward substantially. Jupiter may have moved as close to the Sun as Mars is now. In the process, it swept the asteroid belt nearly clean, leaving only a tenth of one percent of its original population.
As the planets migrated, they stirred the contents of the solar system. Objects from as close to the Sun as Mercury, and as far out as Neptune, all collected in the main asteroid belt.
"The asteroid belt is a melting pot of objects arriving from diverse locations and backgrounds," explains DeMeo.
From a trickle to a river
A new map developed by researchers from MIT and the Paris Observatory charts the size, composition, and location of more than 100,000 asteroids throughout the solar system, and shows that rogue asteroids are actually more common than previously thought. Particularly in the solar system’s main asteroid belt — between Mars and Jupiter — the researchers found a compositionally diverse mix of asteroids.
To create a comprehensive asteroid map, the researchers first analyzed data from the Sloan Digital Sky Survey, which uses a large telescope in New Mexico to take in spectral images of hundreds of thousands of galaxies. Included in the survey is data from more than 100,000 asteroids in the solar system. DeMeo grouped these asteroids by size, location, and composition. She defined this last category by asteroids’ origins — whether in a warmer or colder environment — a characteristic that can be determined by whether an asteroid’s surface is more reflective at redder or bluer wavelengths.
The team then had to account for any observational biases. While the survey includes more than 100,000 asteroids, these are the brightest such objects in the sky. Asteroids that are smaller and less reflective are much harder to pick out, meaning that an asteroid map based on observations may unintentionally leave out an entire population of asteroids.
To avoid any bias in their mapping, the researchers determined that the survey most likely includes every asteroid down to a diameter of five kilometers. At this size limit, they were able to produce an accurate picture of the asteroid belt. The researchers grouped the asteroids by size and composition, and mapped them into distinct regions of the solar system where the asteroids were observed.
From their map, they observed that for larger asteroids, the traditional pattern holds true: The further one gets from the sun, the colder the asteroids appear. But for smaller asteroids, this trend seems to break down. Those that look to have formed in warmer environments can be found not just close to the sun, but throughout the solar system — and asteroids that resemble colder bodies beyond Jupiter can also be found in the inner asteroid belt, closer to Mars.
As the team writes in its paper, “the trickle of asteroids discovered in unexpected locations has turned into a river. We now see that all asteroid types exist in every region of the main belt.”
A shifting solar system
The compositional diversity seen in this new asteroid map may add weight to a theory of planetary migration called the Grand Tack model. This model lays out a scenario in which Jupiter, within the first few million years of the solar system’s creation, migrated as close to the sun as Mars is today. During its migration, Jupiter may have moved right through the asteroid belt, scattering its contents and repopulating it with asteroids from both the inner and outer solar system before moving back out to its current position — a picture that is very different from the traditional, static view of a solar system that formed and stayed essentially in place for the past 4.5 billion years.
“That [theory] has been completely turned on its head,” DeMeo says. “Today we think the absolute opposite: Everything’s been moved around a lot and the solar system has been very dynamic.”
Clark Chapman, a senior research scientist at the Southwest Research Institute in Boulder, Colo., says the new map is a welcome update to the asteroid maps he and his colleagues developed in the 1980s, which included only those asteroids measuring 20 kilometers or more in diameter. In the past two decades, he says, scientists have made leaps in their understanding of asteroids’ dynamics and evolutionary history, which DeMeo and Carry have now put into context.
“What they have done is attempted to at least qualitatively describe how the unexpected relationships between asteroid size, distance from the sun, and composition fit into the current dynamical models and other insights from the past two decades,” Chapman says. “I'm very glad that this basic research has been done, and I think it is a most welcome contribution to understanding the solar system.”
DeMeo adds that the early pinballing of asteroids around the solar system may have had big impacts — literally — on Earth. For instance, colder asteroids that formed further out likely contained ice. When they were brought closer in by planetary migrations, they may have collided with Earth, leaving remnants of ice that eventually melted into water.
“The story of what the asteroid belt is telling us also relates to how Earth developed water, and how it stayed in this Goldilocks region of habitability today,” DeMeo says.
The paper describing these findings appears in the January 30, 2014 issue of Nature.
Posted: 30 Jan 2014 02:03 PM PST
A variety of crops have been successfully harvested on board the International Space Station and verified as safe to eat, a Russian scientist said Wednesday. “The experiments with peas have been very promising,” Margarita Levinskikh, a researcher at the Institute of Biomedical Problems told an annual space conference in Moscow. Russian cosmonauts have also grown Japanese leafy greens and a variety of dwarf wheat that has produced seeds of “just extraordinary quality,” she added. Levinskikh said that next year Russian cosmonauts will sow rice, tomatoes and bell peppers after repairing the station’s Lada greenhouse, a cooperative effort between the institute and the Space Dynamics Laboratory at Utah State University.
Researchers have relied so far on analyzing root modules of the crops to verify them as safe to eat. They plan to grow rice and the grass species purple false brome, whose genomes have already been sequenced, in order to look for possible genetic abnormalities after they have grown in space.
Space-based agriculture has long been of interest to scientists, as plants not only scrub carbon dioxide exhaled by astronauts, but could be used to recycle human waste into food.
Currently all food onboard the International Space Station is flown up on periodic resupply missions.
Long-duration deep space missions without agriculture would require many months’ or years’ worth of food, greatly adding to their launch weight.
Astronauts onboard the ISS already drink water distilled from sweat and urine.
Credit: RIA Novosti
quinta-feira, 30 de janeiro de 2014
Posted: 29 Jan 2014 12:23 PM PST
The human path to Mars should lay through consistent development of space technologies on asteroids and on the Moon. This view expressed the President of RSC Energia Vitaly Lopota and head of Lavochkin Association Viktor Khartov at the Korolyov Readings in Bauman Moscow State Technical University on Tuesday. According to Lopota, in the nearest future, Mars would be a priority in terms of colonization and research. The road map of Mars exploration contemplates two scenarios: to reach it through an asteroid and then through the Moon, or vice versa. “The wise way is to create technology designed for Mars, to use the Moon for testing the required technologies, and the asteroids are a challenge that we should always be able to meet in case of threat,” the expert noted.
Lavochkin is in charge of the landing module of the Russian-European ExoMars project, Khartov said.
"We are creating a two-tonne landing module for this mission. It will transport a 3,000-kilogram European rover to the surface of Mars," he said. The mission starts in 2018, Khartov noted.
Khartov believes that first people should learn how to bring soil from Mars and its satellite Phobos. According to the plan announced by the scientist, the Boomerang project should feature the following pattern of bringing soil from Phobos: a space vehicle delivers on the satellite of Mars a lander that takes soil samples and “shoots upwards a capsule with soil”, which is picked up by another space vehicle near Phobos that sends it to Earth.
|ExoMars rover. Credit: ESA|
The scientist added that this scheme is almost the only possible one to solve the issue of bringing Martial soil to Earth.
The implementation of the Boomerang project is planned for approximately 2020. This project is the first stage of a more large-scale plan dubbed Expedition M, which is scheduled for launch in 2024. It is intended to deliver on Mars a fly-back rocket that would put into orbit a capsule with soil to be picked up by another space vehicle and brought to Earth.
Khartov also recalled that up from 2016, Russia would start its Moon program that should result in bringing Moon soil to Earth.
World’s biggest rocket
Russia’s Roscosmos space agency is to seek government approval to build the world’s largest rocket, its head said Tuesday.
“I think that in the near future, within a month, we will make our suggestions to the Military-Industrial Commission,” Oleg Ostapenko said.
Ostapenko, who was appointed head of the agency in October, said the planned launcher would be able to lift 80 metric tons into low Earth orbit.
It could also be upgraded to launch as much as 160 tons, which would be the heaviest payload every lifted by a single rocket into space.
The current record holder, NASA’s Saturn V rocket that was used to launch Apollo astronauts on their journey to the moon, had a maximum capability of 120 metric tons.
Roscosmos formed a working group last year to evaluate proposals for a heavy-lift rocket, including the revival of the Energia launcher, the highest payload rocket ever built in the country.
The Energia, developed in the Soviet Union and launched twice, was cancelled during the economic crisis twenty years ago.
Experts consider such large rockets to be necessary for manned Mars or deep space missions, although they are likely to be uneconomical for commercial payloads that can be launched on existing rockets.
NASA is currently building a new super-heavy rocket, the Space Launch System, that will also come in two variants capable of lifting 70 and 130 tons into orbit. The first test flight of the smaller version is scheduled for 2017.
Russia’s largest existing rocket, the Proton, can launch payloads of up to 20 tons. The modular Angara rocket is also under development and comes in several versions, the largest of which is planned to send up to 40 tons into orbit.
China is reportedly considering construction of its own super-heavy rocket, the Long March 9, for a manned lunar mission.
Roscosmos is also working with aerospace enterprises on the creation of radar spacecraft, which the Russian group currently does not have, Ostapenko said.
"Radar location is a very important and promising area. Unfortunately, we do not have such capabilities in our orbital spacecraft group. we are now actively contacting a number of enterprises to work on this issue," he said.
The negotiations between the Roscosmos administration and representatives of the industry took place several days ago, he said. However, Ostapenko did not name the enterprises with which negotiations are being held on this issue.
Russia could go it alone after ISS closes
According to Lopota, the Russian segment of the International Space Station could live on as a separate facility after the project’s conclusion.
“By the mid-2020s our American colleagues will have exhausted their technical resources and Russia will have a unique opportunity to use the segment, still to be completed, as an orbiting international port,” Lopota said.
He added that the long-delayed Russian Multipurpose Laboratory Module would only be completed in 2018-2020.
Russian officials have in the past suggested their segment could be detached and operated independently of the ISS as the United States had previously considered leaving the project as early as 2016.
But earlier this month US President Barack Obama vowed to keep the American segment operational until 2024.
Lopota said the Russian segment could still be detached at that time, when its first modules will already be more than 20 years old, to serve as a transit point for international missions headed deeper into space.
As to the Venus mission on which Lavochkin is working, Khartov said, "the Venera-D spacecraft will be launched after 2020". A Proton-M launch vehicle will propel the spacecraft to the skies.
|The Venera-D spacecraft approaching clouds-veiled Venus. Shown configuration was only one of several designs envisioned at the conclusion of the project's definition phase in September 2009. Credit: russianspaceweb.com|
Temperatures are high, approximately 500 degrees Celsius, on the surface of Venus, which means "the spacecraft will have to withstand the planetary surface conditions for about 24 hours," he said.
Venera-D's prime purpose is to make radar remote-sensing observations around the planet Venus in a manner similar to that of the Venera 15 and Venera 16 probes in the 1980s or the U.S. Magellan in the 1990s, but with the use of more powerful radar. The spacecraft is also intended to map future landing sites.