 |
Science Fiction
Dictionary
A B C D E F G H I J K L M N O P Q R S T U V W X Y Z
|
 |
Can 'Dimers' Be Used For Star Trek's Long Range Sensors?
As much as I loved Star Trek in the 1960's, there were some elements of the series' pseudoscience that made me wince. One of them was the idea of a long range sensor that could detect life readings on distant planets. How could you possibly detect life at a distance of light years?
It turns out that it might be possible after all.
Astronomers have found a way to determine the atmospheric pressure of far away worlds using "dimers", molecules that couple to form larger, more complex molecules. In particular, two oxygen molecules.
We present a new method to probe atmospheric pressure on Earth-like planets using (O2-O2) dimers in the near-infrared. We also show that dimer features could be the most readily detectable biosignatures for Earth-like atmospheres and may even be detectable in transit transmission with the James Webb Space Telescope (JWST). The absorption by dimers changes more rapidly with pressure and density than that of monomers and can therefore provide additional information about atmospheric pressures. By comparing the absorption strengths of rotational and vibrational features to the absorption strengths of dimer features, we show that in some cases it may be possible to estimate the pressure at the reflecting surface of a planet.
This method is demonstrated by using the O2 A band and the 1.06 μm dimer feature, either in transmission or reflected spectra. It works best for planets around M dwarfs with atmospheric pressures between 0.1 and 10 bar and for O2 volume mixing ratios above 50% of Earth's present-day level.
Furthermore, unlike observations of Rayleigh scattering, this method can be used at wavelengths longer than 0.6 μm and is therefore potentially applicable, although challenging, to near-term planet characterization missions such as JWST. We also performed detectability studies for JWST transit transmission spectroscopy and found that the 1.06 and 1.27 μm dimer features could be detectable (SNR>3) for an Earth analogue orbiting an M5V star at a distance of 5 pc.
The detection of these features could provide a constraint on the atmospheric pressure of an exoplanet and serve as biosignatures for oxygenic photosynthesis.
We calculated the required signal-to-noise ratios to detect and characterize O2 monomer and dimer features in direct imaging–reflected spectra and found that signal-to-noise ratios greater than 10 at a spectral resolving power of R=100 would be required.
So, given that this method works (there are others), maybe Spock was right all along.

(Spock long range sensor scan)
From Using Dimers to Measure Biosignatures and Atmospheric Pressure for Terrestrial Exoplanets (pdf) via ScienceMag.
Scroll down for more stories in the same category. (Story submitted 3/13/2014)
Follow this kind of news @Technovelgy.
| Email | RSS | Blog It | Stumble | del.icio.us | Digg | Reddit |
Would
you like to contribute a story tip?
It's easy:
Get the URL of the story, and the related sf author, and add
it here.
Comment/Join discussion ( 1 )
Related News Stories -
("
Space Tech
")
'If Anyone Is Watching Earth...'
'Our study of your race has convinced us that you are not fitted to leave your planet in the present state of your civilization.' - Arthur C. Clarke, 1946.
Cloud Of Space Rubbish From China's Long March Rocket
'Within seconds the material was spread out over fifty yards, in a matter of hours it might occupy several cubic miles of space...'
ESA's Draco To Study Heat Of Reentry
'...a synthetic which air-friction would erode.' - EE Doc Smith, 1934.
The United States Space Academy Is Official
'Is our orbit to Space Academy clear?' - Carey Rockwell
Technovelgy (that's tech-novel-gee!)
is devoted to the creative science inventions and ideas of sf authors. Look for
the Invention Category that interests
you, the Glossary, the Invention
Timeline, or see what's New.
|
 |
Science Fiction
Timeline
1600-1899
1900-1939
1940's 1950's
1960's 1970's
1980's 1990's
2000's 2010's
Current News
'If Anyone Is Watching Earth...'
'Our study of your race has convinced us that you are not fitted to leave your planet in the present state of your civilization.'
Epirus High-Power Microwave Defeats Drones
'...the spreading beam of the deranging ray struck them, and Then one toppled and fell. Then another.'
Cloud Of Space Rubbish From China's Long March Rocket
'Within seconds the material was spread out over fifty yards, in a matter of hours it might occupy several cubic miles of space...'
Biomimetic Tendons From Rochu Robotics
'... the curious parallelism to animal motions.'
Living Human Neuron Biological Compute Rack
'The men are dead, but their acquired wisdom lives on and I am the beneficiary.'
Martha Stewart Approves Ojai 'Living Room On Wheels'
'Young people found the driverless car admirable for petting.'
ESA's Draco To Study Heat Of Reentry
'...a synthetic which air-friction would erode.'
Buy A Galaxy? Maybe Start Smaller
'The sky is the limit' just got higher.
The United States Space Academy Is Official
'Is our orbit to Space Academy clear?'
Is There A Global Problem With Who Is Having Children?
'After twenty generations of shillyshallying...'
You Will Eat The Cookies Made From Plastic...
'Our planes are going to start bringing in bales of discarded plastics...'
It's A Giant Robot! You Reporters Have Been Warned!
'... completely forgetting the ship at sight of the awesome figure and great head of the giant Gaut...'
Birds Learn To Sing Pictures ala Frank Herbert's Distrans
'We will fight in the time of fighting.'
ElectionSim: China's 'Ender's Game' Battle Sim, Or Lem's 'Kingdom In A Box'?
'So, Ender, we will now begin your education.'
Tactile Skin Supplier Map
'What strange sensitivity! What an amazing development of science was manifested in every move and act and word of this Robot!'
Flock Stymied By 'Adversarial Fashion'
'Forget the head atop it, the legs below, feet, arms, hands. It compels erasure.'
More SF in the News Stories
More Beyond Technovelgy science news stories
|
 |