August 28, 2014

Neutral Particle Beam Magsails for fast interplanetary delivery of small cargos

At Centauri Dreams, James Benford looks more closely at particle beam driven magsails. He has found a problem for interstellar missions but promise for interplanetary missions and an interplanetary infrastructure.

The first column shows a fast interplanetary probe, with high interplanetary-scale velocity, acceleration 100 m/sec2, 10 gees, which a nonhuman cargo can sustain. Time required to reach this velocity is 27 minutes, at which time the sail has flown to 135,000 km. The power required for the accelerator is 24GW. If the particle energy is 50MeV, well within state-of-the-art, then the required current is 490A. How long would an interplanetary trip take? If we take the average distance to Mars as 1.5 AU, the probe will be there in 8.7 days. Therefore this qualifies as a Mars Fast Track accelerator.

An advanced probe, at 100 gees acceleration, requires 0.78 TW power and the current is 15 kA. It takes only 34 hours to reach Mars. At such speeds the outer solar system is accessible in a matter of weeks. For example, Saturn can be reached by a direct ascent in the time as short as 43 days.

A very advanced probe, an Interstellar Precursor, at 1000 gees acceleration, reaches 0.8% of light speed. It has a power requirement 34 TW and the current is 676 kA. It takes only 8 hours to reach Mars. At such speeds the outer solar system is accessible in a matter of days. For example, Saturn can be reached by a direct ascent in the time as short as a day. The Oort Cloud at 2,000 AU, can be reached in 6 years.

James Benford replied to some of the Centauri Dream commenters in another Centauri Dream article.

Google Lunar Xprize has big Milestones through October 2014 and for the grand prize in late 2015

To win the grand prize of the Google Lunar Xprize ($20 million), private teams (with no more than 10% in government funding) must:

* Land a robot safely on the Moon
* Move 500 meters on, above, or below the Moon’s surface; and
* Send back HDTV Mooncasts for everyone to enjoy

….And this must all be completed before the December 31st, 2015 deadline! There are other prizes, too, for missions like surviving the lunar night and visiting an Apollo site.

XPRIZE and Google have incorporated Milestone Prizes into the Google Lunar XPRIZE in order to reward teams who achieve key milestones on their way to ready their subsystems for launch.

The Milestone Prizes, totalling US$6 million, are for demonstrating (via actual testing and analysis) robust hardware and software to overcome key technical risks in the areas of imaging, mobility and lander systems — all three being necessary to achieve a successful Google Lunar XPRIZE mission. Milestone Prizes are available in each of those three categories and the prize value and maximum number of winning teams for each are summarized below.

There are still 16 active teams. There are five leading teams who are finalists for at least one of the milestone prizes.

Astrobotic and Moon Express would be considered the leaders are they are finalists in all three milestone prizes. Astrobotic also has booked a rocket launch on a Spacex Falcon 9 for October 2015. They are the primary payload and have sold secondary payload space to defray costs. If Astrobotic and Moon Express succeed they plan to perform lunar missions for NASA and other space agencies.

In April 2011, Astrobotic received a $599,000 two-year contract to develop a scalable gravity offload device for testing rover mobility in simulated lunar gravity under NASA's Small Business Technology Transfer Program (STTR).

On April 30, 2014 NASA announced that Astrobotic Technologies was one of the three companies selected for the Lunar CATALYST initiative. NASA is negotiating a 3 year no-funds-exchanged Space Act Agreement (SAA). The Griffin Lander may be involved

Astrobotic plans on further robotic missions to the moon and Mars.
Astrobotic Griffin Lander

Moon Express is working with Autodesk Moon Express will send a series of robotic spacecraft to the Moon for ongoing exploration and commercial development. The opportunity is simply driven by advances in technology. What used to require the unlimited budgets of a superpower, are now within reach of private enterprise.

On June 30, 2011, the company held its first successful test flight of a prototype lunar lander system called the Lander Test Vehicle (LTV) that was developed in partnership with NASA.

In mid-2012, Moon Express announced that it will work with International Lunar Observatory Association (ILOA) to put a shoebox-sized astronomical telescope on the Moon. Additional details were released in July 2013, including that there would be two telescopes: a 2 meters (6 ft 7 in) radio telescope as well as an optical telescope. The preferred location is 5 kilometers (3.1 mi)-high Malapert crater, with current plans to land the mission no earlier than 2018.

As of November 2012, MoonEx has 20 employees, plans to stage a public demonstration in the fall of 2013, and has announced that they will be ready to land on the Moon by early 2015.

In December 2013, MoonEx unveiled the MX-1 lunar lander, a toroidal robotic lander that uses high-test hydrogen peroxide as its rocket propellant to support vertical landing on the Lunar surface.

On April 30, 2014 NASA announced that Moon Express Inc. was one of the three companies selected for the Lunar CATALYST initiative. NASA is negotiating a 3 year no-funds-exchanged Space Act Agreement (SAA)

Moon Express MX-1 Lunar Lander

Undersea tunnels and high speed rail will bring people and freight to mostly 8 hours trips or less from Beijing within China

Construction of an extraordinary underwater high-speed rail tunnel in China’s Bohai Strait is likely to start some time after 2016, Chinese media report.

The proposed undersea link would stretch more than 100km under Bohai Bay to become the world’s longest undersea tunnel, connecting the cities of Dalian and Yantai.

Experts say it will put the two cities within a 40-minute train ride of each other, where now a ferry-ride takes eight hours, while driving around Bohai Bay is a 1,400km road trip.

Wang Mengshu, the rail expert, said all provincial capitals will be linked to Beijing via high-speed rail, and that travelling times will be reduced to eight hours, except on routes between Beijing, Urumqi and Lhasa.

Any two of these provincial capitals will also be linked by high speed rail, he added.

Wang pointed out the coastal railway stretching from northeast China via 11 provincial regions to south China's Hainan province, covering a length of 5700 kilometres, as a crown achievement.

The coastal railway will traverse Bohai and Qiongzhou straits via an underwater channel. Once complete, it will become a main route for energy transportation, he added.

China is also mulling a railway that stretches from China to Singapore via Thailand and Malaysia

August 27, 2014

US oil production again reaches a new post mid-1980s record

US total all liquids oil and crude oil daily production again reached new post mid-1980s peaks. Crude oil production was at 8.63 million barrels per day. It is about 320,000 barrels per day from passing the mid-1980s peak. The overall US peak production was in 1970 at about 9.6 million barrels per day.

North Dakota oil 1.09 million barrels in June 2014. North Dakota oil production is believed to be about 1.2 million barrels per day in August.

North Dakota and Texas oil production is driving the increases in US oil production.

New Cray GPU supercomputer will provide a petaflop of power in 4 Cabinets

[HPCWire] The new Cray CS-Storm, which offers up to 8 NVIDIA K40s per 2U server and a peak performance of 11 teraflops per Ivy Bridge-outfitted node, is set to push key applications that require more GPU scalability to new heights.

The system, which is based on the Cray CS300 super, is designed to keep the accelerators cool enough to operate at full speed. The 48U standard rack can accommodate 22 of the 2U nodes, which means that with 2 Ivy Bridges and the GPUs, users are looking at around 250 teraflops per rack or a petaflop of performance for a 4-cabinet purchase. Cray’s Barry Bolding told us that the company will release more information on future Intel generations for the host processor.

It’s not just about adding GPUs into the dense mix with this system, however. Cray has tuned the GPU workloads they’re targeting for maximum bandwidth and accelerator performance on the cooling and data movement fronts with a couple of notable features.

While these are air-cooled systems, as the graphic below shows, the emphasis is on cooling through front to back airflow to keep the GPUs humming without overheating or without having to run them at reduced wattage. In addition to airflow, this allows for expandability options since it will be possible to add future generations of accelerators into the box while still allowing the desired density and the ability to cool all 8 of the GPUs at the same time.

Cruising at Mach 3 or a bit more with a supercativation submarine

What power is needed to get to mach 3 constant velocity for a supercativating submarine ? A Supercativating submarine could in theory achieve about 3600 miles per hour but powering the propulsion is a technical challenge.

Goatguy provides the energy for water displaced, times its density, times ½, times its outward radial velocity squared would be the amount of energy invested every second in the slipstream bubble's frontal profile. Maybe more, but this is kind of a minimum. The drag for supercativiation is 200,000 times less so the water displacement is an approximation.

The 1,000 meter per second bullet with a 20° cone uses 1,500,000 J/s (watts) of energy to perpetually keep its 1000 m/s velocity. That is due entirely to the displaced water, and its outward radial velocity dependent on the angle-of-attack of the frontal cone. There's no provision for invested-energy recycling (allowing the collapse of the bubble to propel the tail, to whatever degree water dynamics allows such action), but I'm betting the situation isn't much better at that end, either. Maybe what, get back 70% of the energy? That'd be nice. So, maybe 500,000 W to keep the bullet flying.

And that's a bullet with a cross section of π × 0.0045² m². Now wait a moment: here's the bad news … at the cross-section of a useful human scale sub (5 meters across, which is pretty cramped, considering all that nuclear reactor equipment and such needs also to be on board), the ratio is (D/d)² or (5 ÷ 0.0045)² = 300,000× larger. 300,000 × 500,000 W = 150 billion watts. Assuming that you get back 70% of the invested displacement energy.

German Type VII U-boat submarines were 4.7 meter across at the beam for their pressurized hull

The longest submarine was the USS Triton which were 136 meters long.

A MUCH pointier cone (4°, it only requires 4 gigawatts of motive energy. Well, at 1°, where the ship is 100× longer than it is wide (500 meters long, for a 5 meter wide ship.), you're still looking at 500 megawatts of energy to keep the thing chugging along at Mach3.

I do not think the 1° submarine is unreasonable.

August 26, 2014

DARPA 5 beyond GPS technologies for position, navigation and timing

As revolutionary as GPS has been, however, it has its limitations. GPS signals cannot be received underground or underwater and can be significantly degraded or unavailable during solar storms. More worrisome is that adversaries can jam signals. GPS continues to be vital, but its limitations in some environments could make it an Achilles’ heel if warfighters rely on it as their sole source of PNT information. To address this problem, several DARPA programs are exploring innovative technologies and approaches that could eventually provide reliable, highly accurate PNT capabilities when GPS capabilities are degraded or unavailable.

DARPA’s current PNT portfolio includes five programs, focused wholly or in part on PNT-related technology:

1. Adaptable Navigation Systems (ANS) is developing new algorithms and architectures for rapid plug-and-play integration of PNT sensors across multiple platforms, with the intent to reduce development costs and shrink deployment time from months to days. ANS aims to create better inertial measurement devices by using cold-atom interferometry, which measures the relative acceleration and rotation of a cloud of atoms stored within a sensor. The goal is to leverage quantum physical properties to create extremely accurate inertial measurement devices that can operate for long periods without needing external data to determine time and position. Additionally, ANS seeks to exploit non-navigational electromagnetic signals--including commercial satellite, radio and television signals and even lightning strikes--to provide additional points of reference for PNT. In combination, these various sources are much more abundant and have stronger signals than GPS, and so could provide position information in both GPS-denied and GPS-degraded environments.

DARPA is pioneering the next-generation of PNT capabilities beyond GPS, which includes using miniaturization, pulsed lasers, quantum physics and even lightning strikes for external navigational fixes.