September 14, 2015

Carnival of Space 423

1. Planetaria - New study helps answer mystery of what happened to Mars’ early atmosphere

Mars used to have a thicker atmosphere and water on its surface, but what happened to that atmosphere has been a mystery. New research may finally help answer that question. Image Credit: M. Kornmesser/ESO

A new analysis of the largest known deposit of carbonate minerals on Mars suggests that the original Martian atmosphere may have already lost most of its carbon dioxide by the era of valley network formation.

"The biggest carbonate deposit on Mars has, at most, twice as much carbon in it as the current Mars atmosphere," said Bethany Ehlmann of the California Institute of Technology and NASA Jet Propulsion Laboratory, both in Pasadena. "Even if you combined all known carbon reservoirs together, it is still nowhere near enough to sequester the thick atmosphere that has been proposed for the time when there were rivers flowing on the Martian surface."

This view combines information from two instruments on a NASA Mars orbiter to map color-coded composition over the shape of the ground within the Nili Fossae plains region of Mars. Image credit: NASA/JPL-Caltech/JHUAPL/Univ. of Arizona

2. Universe Today - The (Possible) Dwarf Planet 2007 OR10

2007 OR10 is a Trans-Neptunian Object (TNO) located within the scattered disc that at one time went by the nicknames of “the seventh dwarf” and “Snow White”. Approximately the same size as Haumea, it is believed to be a dwarf planet, and is currently the largest object in the Solar System that does not have a name.

It was the seventh object to be discovered by Michael Brown’s team (after Quaoar in 2002, Sedna in 2003, Haumea and Orcus in 2004, and Makemake and Eris in 2005).


An artist’s conception of 2007 OR10, nicknamed Snow White. Astronomers suspect that its rosy color is due to the presence of irradiated methane. Credit: NASA





3. Planetaria - Onward!: NASA selects next destination for New Horizons in Kuiper Belt


4. Universe Today - Looking for a Challenge? Design a Way to Keep Increasingly Crowded Airspace Safe

5. Nextbigfuture - DE-STAR, or Directed Energy System for Targeting of Asteroids and exploRation, is the brainchild of UC Santa Barbara physicist Philip Lubin and Gary B. Hughes. DE-STAR initial objective is to deflect asteroids.

The DE-STAR system could be leveraged for many other uses, such as stopping the rotation of a spinning asteroid and achieving relativistic propulsion.

Tests simulated space conditions. Using basalt — the composition of which is similar to known asteroids — they directed a laser onto the basalt target until it glowed white hot — a process called laser ablation, which erodes material from the sample. This changes the object’s mass and produces a “rocket engine” using the asteroid itself as the propellant. In space, this would be powerful enough to alter its course.

Lab measurements have shown that in terms of thrust, the conversion of laser energy to force through this method is about 100 micronewtons per watt, which works out to 10 kilowatts per newton


6. Nextbigfuture - The impossible task of traveling 25.6 trillion miles to Alpha Centauri, our closest star, is now possible. Using a Directed Energy System for Targeting of Asteroids and exploRation (DE-STAR), a versatile, scalable phased-array laser system, it can be reached in a short 16 years. Our project entails carrying out both computational and experimental studies of specific uses of DE-STAR to investigate photon recycling and spacecraft propulsion. Photon recycling is a unique term used to describe a form of energy conservation relative to this project. This effect will greatly improve the efficiency of spacecraft making interstellar flight more plausible. What lies beyond our solar system is one of the biggest mysteries of mankind and it finally has the potential to be solved.

The DESTAR interstellar laser propulsion system is modular, scalable and on a very rapid development path. It lends itself to a roadmap.

There has been a game change in directed energy technology whose consequences are profound for many applications including photon driven propulsion. This allows for a completely modular and scalable technology without "dead ends".

Laser efficiencies are near 50%. The rise in efficiency will not be one of the enabling elements along the road map but free space phase control over large distances during the acceleration phase will be. This will require understanding the optics, phase noise and systematic effects of our combined on-board metrology and off-board phase servo feedback.

Reflector stability during acceleration will also be on the critical path as will increasing the TRL of the amplifiers for space use. For convenience we break the roadmap into several steps. One of the critical development items for space deployment is greatly lowering the mass of the radiators. While this sounds like a decidedly low tech item to work on, it turns out to be one of the critical mass drivers for space deployment. Current radiators have a mass to radiated power of 25 kg/kw, for radiated temperatures near 300K. This is an area where some new ideas are needed. With our current Yb fiber baseline laser amplifier mass to power of 5kg/kw (with a likely 5 year roadmap to 1 kg/kw) and current space photovoltaics of less than 7 kg/kw, the radiators are a serious issue for large scale space deployment.

The same basic system can be used for many purposes including both stand-on and stand-off planetary defense from virtually all threats with rapid response, orbital debris mitigation, orbital boosting from LEO to GEO for example, future ground to LEO laser assisted launchers, standoff composition analysis of distant object through molecular line absorption, active illumination of asteroids and other solar system bodies, beamed power to distant spacecraft among others. The same system can also be used for beaming power down to the Earth via micro or mm waves for selected applications. This technology will give us transformative options that are not possible now and allows us to go far beyond our existing chemical propulsion systems.

Consider a 1 gram payload attached to a 0.7 meter diameter sail. Image Adrian Mann


Operational Maturation and Steps:

Step 1 - Ground based - Small phased array, beam targeting and stability tests - 10 kw
Step II – Ground based - Target levitation and lab scale beam line acceleration tests - 10 kw
Step III – Ground based - Beam formation at large array spacing –
Step IV – Ground based - Scale to 100 kW with arrays sizes in the 1-3 m size –
Step V – Ground based - Scale to 1 MW with 10 m optics –
Step VI – Orbital testing with small 1-3 class arrays and 10-100kw power – ISS possibility
Step VII – Orbital array assembly tests in 10 m class array
Step VIII – Orbital assembly with sparse array at 100 m level –
Step IX – Orbital filled 100 m array
Step X – Orbital sparse 1km array
Step XI – Orbital filled 1 km array
Step XII – Orbital sparse 10 km array
Step XIII – Orbital filled 10 km array

7. Nextbigfuture - Elon Musk told Stephen Colbert, Spacex will be ready for human passengers within two to three years.

Mars is "a fixer upper of a planet," Musk says, but it can be made to be more like Earth if it can be made hotter. When it comes to turning on the planetary furnace, there's a slow way and fast way, he explained.

The slow way is to release greenhouse gases, the same process being blamed for global warming on Earth. The fast way is to drop nuclear weapons over Mars' poles.

Musk says his rocket firm, Space Exploration Technologies, or SpaceX, will be capable of ferrying astronauts to the International Space Station in two or three years. At present, SpaceX' Falcon rockets deliver cargo to the ISS.


8. Nextbigfuture - Spacex is showing off the inside of the manned Dragon space vehicle. It clearly shows that Elon Musk is reusing some of the Tesla Luxury electric car design. It is not just pretty but it is highly functional with new emergency escape systems and rockets for propulsive landing.


Crew Dragon features an advanced emergency escape system (which was tested earlier this year) to swiftly carry astronauts to safety if something were to go wrong, experiencing about the same G-forces as a ride at Disneyland.

Форма для связи

Name

Email *

Message *