Since I was a young child Mars held a special fascination for me. It was so close and yet so faraway. I have never doubted that it once had advanced life and still has remnants of that life now. I am a dedicated member of the Mars Society,Norcal Mars Society National Space Society, Planetary Society, And the SETI Institute. I am a supporter of Explore Mars, Inc. I'm a great admirer of Elon Musk and SpaceX. I have a strong feeling that Space X will send a human to Mars first.
Cassini spacecraft observations indicate Saturn's moon Titan is more Earth-like
Written by Jeanne Rife on 28 Apr 2016
Oceanographers can possibly study alien worlds sooner than thought. NASA's Cassini spacecraft observations have indicated that Saturn's moon Titan is a lot like our planet Earth, with its thick atmosphere, surface filled with lakes and probable wetlands.
NASA said that besides Earth, Titan is the sole known world in the solar system that has a stable liquid on its surface. Cassini has discovered over 620,000 square miles of surface of Titan covered in liquid, nearly 2% of its surface, since 2004. Planetary scientists used to ponder over what elements fill the liquid bodies of Titan, but thanks to Cassini as now they have got the answer.
The current study was conducted between 2007 and 2015 with the help of Cassini’s radar instrument for analyzing the second largest sea of Titan, called Ligeia Mare, and it revealed that the sea was filled with methane.
Published in the ‘Journal of Geophysical Research: Planets’, the study has given confirmation to what planetary scientists used to think about Titan's seas.
According to the news release, with the help of Cassini’s radar instrument for the detection of the echoes from the seafloor of Ligeia Mare, scientists have used the depth-sounding information to examine temperatures, which proved helpful in providing clues regarding their composition.
Study lead author, Alice Le Gall, a Cassini radar team member, said, “Before Cassini, we expected to find that Ligeia Mare would be mostly made up of ethane, which is produced in abundance in the atmosphere when sunlight breaks methane molecules apart. Instead, this sea is predominantly made of pure methane”.
NASA said that the size of Ligeia Mare is about the size of Lake Huron and Lake Michigan together. Thanks to Cassini’s flybys scientists managed to know that the sea was 525 feet deep at a few sites.
"The latest data NASA researchers have been pouring over shows new details about the strange lakes and seas that trickle across Saturn’s frigid moon, Titan. It also draws comparisons between the only other interstellar body found to have similarly liquid lakes and seas on its surface—our very own Earth. Unlike our watery planet, though, Titan’s lakes and seas are made up of pure liquid methane," according to a news report published by Gizmodo.
But how do the seas stay filled up with all that methane? One potential new explanation takes the liquid cycle we see here on Earth, tweaks it slightly to account for Titan’s own conditions, and comes up with something pretty familiar: Rain.
According to a report in CNET by Michelle Starr, "The final mission is, fittingly, called the Grand Finale, and there's a lot more involved than simply falling down. As the probe gets closer and closer to Saturn, it will have an unprecedented opportunity to study its minutiae, as detailed by NASA's Linda Spilker at the European Geosciences Union General Assembly last week."
Don't cry for Cassini, though. Its mission has already been extended twice, far exceeding its four-year expectation, and its running out of fuel. Leaving it in unfueled orbit around the planet risks crashing into Enceladus or Titan, the potentially life-sustaining liquid water on which could be contaminated by microbes that could still be living on Cassini, even after 20 years.
A report published in SpaceDaily informed, "Saturn's largest moon is covered in seas and lakes of liquid hydrocarbons - and one sea has now been found to be filled with pure methane, with a seabed covered by a sludge of organic-rich material, and possibly surrounded by wetlands."
Both Earth and Titan have atmospheres dominated by nitrogen, over 95% in Titan's case. However, unlike Earth, there is little oxygen: the remaining is mostly methane, with a small amount of hydrogen, and trace amounts of other gases such as ethane.
Scientists are getting closer to finding worlds that resemble our own "blue marble" of a planet. NASA's Kepler mission alone has confirmed more than 1,000 planets outside our solar system -- a handful of which are a bit bigger than Earth and orbit in the habitable zones of their stars, where liquid water might exist. Some astronomers think the discovery of Earth's true analogs may be around the corner. What are the next steps to search for life on these potentially habitable worlds?
Scientists and engineers are actively working on two technologies to help with this challenge: the starshade, a giant flower-shaped spacecraft; and coronagraphs, single instruments that fit inside telescopes. Both a starshade and a coronagraph block the light of a star, making it easier for telescopes to pick up the dim light that reflects off planets. This would enable astronomers to take pictures of Earth-like worlds -- and then use other instruments called spectrometers to search the planets' atmospheres for chemical clues about whether life might exist there.
A new JPL "Crazy Engineering" video visits both technologies at NASA's Jet Propulsion Laboratory in Pasadena, California:
"Coronagraphs are like visors in your car -- you use them to block the light of the sun so you can see the road," said Nick Siegler, the program chief technologist for NASA's Exoplanet Exploration Program Office at JPL. "Starshades, on the other hand, are separate spacecraft that fly in front of other telescopes, so they are more like driving behind a big truck in front of you to block the light of the sun." Siegler is featured in the Crazy Engineering video.
The starshade would be a large structure about the size of a baseball diamond that deploys in space and flies in front of a space telescope. To view an animation of the starshade unfurling in space, and footage of a prototype at Northrop Grumman's Astro Aerospace in Carpinteria, California, visit:
Coronagraphs, which use tiny masks to block the light of stars from within a telescope, are also currently in development at JPL, as part of NASA's Wide-Field Infrared Survey Telescope, or WFIRST, mission, led by NASA's Goddard Space Flight Center in Greenbelt, Maryland. A feature story describing how these structures might help glean signs of life on other planets is online at:
University College London (UCL) has released images of the Martian surface with five times the resolution of anything previously sent back from Mars orbit. The images come courtesy of the new Super-Resolution Restoration (SRR) imaging technique developed by a UCL research team, which takes images from spacecraft orbiting Mars and stacks and matches them to create new, more detailed images of the Beagle 2 lander, ancient Martian lake beds, and the tracks of the NASA MER-A rover.
The fleet of orbiters now circling the Red Planet have added a bonanza of data to our knowledge and in four decades have mapped Mars with a detail that took centuries to do for the Earth. Unfortunately, the images they can send back is limited by the size of the telescopes that can be sent with the orbiters. According to UCL, these smaller optics combined with atmospheric interference and restricted bandwidth of Mars-Earth communications limits image resolution to about 25 cm (10 in).
To help overcome this, UCL's SRR takes existing images taken from orbit at different angles and stacks and matches them to produce images that can resolve objects as small as 5 cm (2 in) in diameter. In the recent study, the team took stacks of four to eight 25-cm images from the NASA HiRISE camera, which came back with high enough resolution to zoom in on specific objects like the failed Beagle 2 lander.
close up of Beagle 2 site comparing original and SRR
"Using novel machine vision methods, information from lower resolution images can be extracted to estimate the best possible true scene," says Yu Tao, Research Associate at UCL. "This technique has huge potential to improve our knowledge of a planet's surface from multiple remotely sensed images. In the future, we will be able to recreate rover-scale images anywhere on the surface of Mars and other planets from repeat image stacks."
UCL says that the technique was used on Mars because most features on the Martian surface remain stable for millions of years. As a result, the researchers were able to use images taken over a 10-year period and match them with, in the words of Jan-Peter Muller of the UCL Mullard Space Science Laboratory, "the equivalent of drone-eye vision anywhere on the surface of Mars where there are enough clear repeat pictures."
MER-A rover tracks comparing original and SRR
By contrast, Earth is a very poor candidate because it is so dynamic due to atmospheric turbulence that images can alter dramatically within seconds of one another.
According to UCL, the new images provide new evidence that the landing site of Beagle 2 has been correctly identified and the team hopes that SRR can find not only other failed landings, but also identify safe landing sites for future missions and provide rover-level images from orbit.
"As more pictures are collected, we will see increasing evidence of the kind we have only seen from the three successful rover missions to date," says Muller. "This will be a game-changer and the start of a new era in planetary exploration."
SpaceX, the space launch company founded by Elon Musk, plans to send a spacecraft to Mars as soon as 2018, in the first stage of an audacious plan to establish a human colony on Earth’s nearest neighbour.
News of the plans emerged on Wednesday after Nasa, the US space agency, published details of an agreement under which it would support the voyage of a SpaceX Red Dragon craft to the planet.
The plans — the first interplanetary mission by a commercial company — mark the first stage in the realisation of Mr Musk’s vision to turn humans into a species living on more than one planet. However, the small craft — based on SpaceX’s resupply capsules for the International Space Station — will be uncrewed.
SpaceX confirmed the plans on its Twitter and Facebook accounts. It said the Red Dragon missions would support the technologies needed to “land large payloads propulsively on Mars”. Mr Musk is expected to announce fuller details of his plans for a Mars colony at a conference in Guadalajara, Mexico, in September.
“Red Dragon missions to Mars will help inform the overall Mars colonisation architecture that SpaceX will reveal later this year,” the company said.
The Mars announcement came on the same day that the US Air Force awarded SpaceX its first ever contract to launch a US national security satellite. The company will be paid $87.2m to carry a GPS satellite into orbit next May. The company won the right to launch spy satellites — previously a monopoly of United Launch Alliance — in May last year.
Dava Newman, a Nasa deputy administrator, wrote in a blog post about the agency’s plans for a crewed mission to Mars that the agency was “particularly excited” about the SpaceX project, one of several co-operation deals with private companies.
“In exchange for Martian entry, descent and landing data from SpaceX, Nasa will offer technical support for the firm’s plan to attempt to land an uncrewed Dragon 2 spacecraft on Mars,” Ms Newman wrote.
The agreement commits Nasa to offer SpaceX help with deep space navigation and communications, design of the spacecraft’s trajectory and help with developing the landing system.
The SpaceX mission will use a version of the Dragon spacecraft that currently flies to the International Space Station under SpaceX’s resupply contracts with Nasa. As part of work to develop a version of the capsule that can carry astronauts, SpaceX has developed and tested motors that allow the craft to make a safe landing on earth in the event of an emergency during take-off. SpaceX would adapt that system to allow the craft to touch down on Mars.
SpaceX released a YouTube video of a test of the system on a launch pad in Texas, filmed in November.
The craft would be launched on its journey by SpaceX’s new Falcon Heavy rocket, a heavy-lift version of its existing Falcon 9, which it expects to fly for the first time later this year. Because interplanetary missions require spacecraft to be launched from earth’s surface faster than orbital flights such as missions to the space station, they depend on heavy rockets, usually three standard rockets strapped together.
At present, the US’s only heavy-lift rocket is United Launch Alliance’s expensive Delta IV Heavy. SpaceX expects that the Falcon Heavy will offer a far more economic heavy launch capability.
While SpaceX did not say how long it expected Red Dragon’s trip to take, journey times to Mars for space probes are generally between three and six months, depending on the route taken.
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