Print 25 comment(s) - last by 91TTZ.. on Nov 16 at 4:33 PM

Dragon may eventually provide solace to U.S. manned space efforts

While highly anecdotal, an example of the arguably shifting balance of global power can be observed in the fact that China is now regularly sending astronauts into space, while the U.S. is, for the most part, grounded in terms of manned space flight.

I. China Continues Manned Flight Progress

China is planning a fifth manned space mission.  Slotted for June 2013, the mission will test an upgraded capsule-type spacecraft, which will be replacing the proven 3-passenger Shenzhou 9.

While crude by space-plane standards, the Shenzhou 9 performed remarkably well, safely ferrying Chinese astronauts (aka "taikonauts") into orbit.  In June, China sent its first female Taikonaut -- Liu Yang -- into space.  She helped the Shenzhou 9 spacecraft manually dock with an orbiting spacelab, which launched in 2011.

China will send more Taikonauts into space in 2013 as it moves towards making its own space station. [Image Source: NPR]

China is also mastering the art of unmanned space flight. In June, its Shenzhou 8 automated capsule-orbiter successfully docked with the Tiangong-1 space lab, a Chinese orbiting laboratory that is performing zero gravity experiments on live fish, plants, worms, bacteria, and human cancer cells.

China has plans for an orbiting space station, which will go operation by 2020, and longer term plans of establishing a moon colony.  China initially considered joining the International Space Station (ISS) effort, but amidst trade tensions with the U.S., is currently pursuing plans for its own private rival station.  

The Chinese space station is expected to weigh around 60 tons, versus the much larger 400-ton ISS.  One major difference in the concept art sketches of the upcoming station, is a reduced solar panel footprint, this hints that the Chinese station may feature less power electronics.

China space station
The Chinese space station will be smaller than the iSS with less solar panels.
[Image Source: BBC News]

The unnamed upcoming station will feature two lab modules, a 20-ton central habitation module, and a pair of ports to allow a robotic supply capsule and a manned capsule to simultaneously be docked.

II. Shenzhou vs. Dragon vs. Soyuz vs. Apollo D-2 

The Shenzhou capsules are similar to the General Electric Comp.'s (GE) Apollo mission proposal (D-2), which was similar to the later Russian Soyuz capsule.  It should be noted that GE's D-2, Russia's Soyuz, and China's Shenzhou all have slightly different dimensions, suggesting that while they share a common design direction, none of the capsules is a direct "clone" or "copy" of the other [sourcesource].

Manned spacecraft
China's Shenzhou is similar to Soyuz in general design. [Image Source: Wikimedia Commons]

America is currently ferrying astronauts to and from the ISS in Soyuz capsules.  It is finally expected to regain its own domestic launch capability sometime between 2015 and 2017, when SpaceX (Space Exploration Technologies Comp.) -- Elon Musk's private startup -- finishes its human-rated variant of the Dragon capsule.

With both China and the U.S. pursuing capsule-based designs, it's interesting to compare and contrast the differences.  The main difference is that the Dragon lacks a forward orbital module; limiting the amount of time the crew can spending in orbit.  The orbital and reentry modules cumulatively have 14 cubic meters of habitable space (8 in the unshielded orbital module, 6 from the shielded reentry module), versus approximately 10 cubic meters for the Dragon in the single shielded reentry module.
A manned version of the SpaceX Dragon (pictured version is unmanned) will be finished in the new few years. [Image Source: SpaceX/NASA]

The manned variant of the Dragon will be carried aboard a SpaceX Falcon 9 v1.1 rocket (a refreshed version of the current Falcon 9 v1.0) with 5.88 Mega-Newtons of initial thrust.  Comparatively the Shenzhou capsules are delivered aboard a Long March 2F rocket, which provides 5.923 Mega-Newtons of thrust (reportedly) upon takeoff.

It's interesting to observe how that despite the differences in design, the final amount of thrust delivered by the rockets is quite similar.

Comments     Threshold

This article is over a month old, voting and posting comments is disabled

RE: Launch Center location?
By JasonMick on 11/12/2012 4:57:21 PM , Rating: 2
I'm surprised that the Chinese Launch Center is so far to the North. I wonder why they didn't build it closer to the Equator like most other nations.
Interesting point.

This explains in good layman terms why the equatorial launch is favorable:

According to Google, the Chinese center is located at 39.7667° N.

That's nearly 10 degrees further north than the U.S. site, but it's also further south than the Russian site -- the Baikonur Cosmodrome in Kazakhstan @ 45.6° N.

I would guess the Chinese space program started by examining the Soyuz rocket designs from old decommissioned hardware, hence its thrust profile matched Soyuz, hence they wanted to position their launch center as far north as possible, such that it was close latitude-wise to the Russian launch center.

As rockets launch east, Soyuz rocket modules may well have crash-landed in China. While the damage would likely be great, the Chinese may have gleaned clues on their rocket building from Soyuz, nonetheless.

Also, launching further North helps distance the launches from India, who has a rival space program of its own.

Just some hypotheses, but those could be couple of reasons for the positioning.

RE: Launch Center location?
By Solandri on 11/12/2012 6:30:48 PM , Rating: 3
The equatorial orbit launched from the equator requires the least energy, but you're stuck flying over the equator. These are ideal for geostationary (not just geosynchronous) satellites.

If you want greater coverage of the earth's surface, like a spy satellite, you want a more inclined orbit. For equal coverage of 100% of the earth's surface, you need a completely polar orbit (flies over the poles). For a polar orbit, the eastward velocity of an equatorial launch is actually undesirable (you have to burn additional fuel to get rid of it).

But the North and South poles aren't very interesting, and the most effective orbit for coverage is highly inclined but not quite polar. Most of the places people live are about midway between the poles and equator, and a launch from slightly north of that region puts you into an inclined orbit with the greatest loiter time over this region, for the least amount of launch energy.

Other considerations are what's downrange from your launch site. The U.S. does its highly inclined orbit launches from Vandenberb AFB, just northwest of Los Angeles. Launches are to the south, over the Pacific Ocean, which is where debris will fall if the launch fails. There's a NASA Landsat satellite which is supposed to be launched there from an Atlas V in February which I'm planning to go watch.

Equator = launching cheaply
Far north (or south) = spying or surveillance

RE: Launch Center location?
By DanNeely on 11/12/2012 6:40:28 PM , Rating: 2
I think it's more likely that location started out as an IRBM/ICBM test location and space research was a tacked on extra added at a later date. For hitting Soviet/American locations a northerly location is preferred; and the Long March rockets China's currently using for space travel are closely related to the ICBM's they're derived from. This was a deal killer for IIS participation; the level of technical data the US demanded to prove the rockets were safe enough to service the station was well in excess of what China was (or could reasonably be expected to be) willing to reveal about a strategic weapon system.

RE: Launch Center location?
By delphinus100 on 11/12/2012 8:44:39 PM , Rating: 3
As rockets launch east, Soyuz rocket modules may well have crash-landed in China. While the damage would likely be great, the Chinese may have gleaned clues on their rocket building from Soyuz, nonetheless.

Unlikely. Aside from the fact that China would take quite unkindly to having lower stages dropped on them, the Russians have always taken a performance hit by flying trajectories out of Tyuratam that don't overfly China.

Soyuz-18a in 1975 suffered a staging problem of some kind while ascending to orbit to rendezvous with Salyut-4, and had to abort to an emergency landing. The crew had to be reassured several times that they would not descend into Chinese territory, knowing they were not very far north of it...

"I mean, if you wanna break down someone's door, why don't you start with AT&T, for God sakes? They make your amazing phone unusable as a phone!" -- Jon Stewart on Apple and the iPhone

Most Popular Articles5 Cases for iPhone 7 and 7 iPhone Plus
September 18, 2016, 10:08 AM
Laptop or Tablet - Which Do You Prefer?
September 20, 2016, 6:32 AM
Update: Samsung Exchange Program Now in Progress
September 20, 2016, 5:30 AM
Smartphone Screen Protectors – What To Look For
September 21, 2016, 9:33 AM
Walmart may get "Robot Shopping Carts?"
September 17, 2016, 6:01 AM

Copyright 2016 DailyTech LLC. - RSS Feed | Advertise | About Us | Ethics | FAQ | Terms, Conditions & Privacy Information | Kristopher Kubicki