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Comment Re:That came in at a pretty steep angle (Score 0) 206

The reason is simpler, actually. The stage has significant horizontal velocity because it is coming back from too far away. There is a boost back burn right after MECO which reverses the direction the stage is going. It is not practical to move it horizontally at that speed while keeping it vertically straight (too much wind resistance can break the stage). So it has to lose both horizontal and vertical velocity at the exact moment of touch down, while straightening up at the same time. Straightening and stabilization of the rocket is done by a combination of reaction control thrusters, grid fins, and the landing burn of the central engine. The points you raise are also valid of course.

Comment Re:Hero worship comes in all sizes (Score 4, Insightful) 273

If you and I are given the same resources as Jobs, could we have created a Mac or iPhone? Jobs' greatness is not because he was a great inventor (though media simplifies it to that). But it is the ability to put all the resource available to him to realize a dream. I say this even though I am not a fan of Jobs or Apple. Quite the opposite.

Same applies to Musk. Of course he was utilizing government subsidy as much as possible for Solar City and Tesla. Of course Falcon 9 and Dragon received significant government funding. But most of his competitors have the same resources available to them to even larger extent. Why weren't they able to produce a product that is as successful? It is in the ability to dream, and put together what he has to realize it.

Comment Toughest part in transition (Score 3, Interesting) 125

I have been a programmer for all of my career, and had management roles in the past 10 years to varying degrees. Over this period, I have also mentored other technical team members in transitioning to management roles. The toughest part of that process is in learning the ability to delegate. This is especially tough for talented programmers.

You often feel that it is easier for you to do a particular task yourself rather than delegating. It may be true that you might finish the work in tenth of the time it takes someone else to do, and you may be spending more time in explaining it to others. But at some point you have to stop doing it, start trusting others to deliver, and don't meddle with their work too often. Once you learn how to do it, you are well on your way to becoming a successful manager.

Submission + - Petition to Restore NASA Commercial Crew Funding

Sivaraj writes: US Senate has decided underfund the NASA Commercial Crew program by $344 million. The program has already been delayed significantly in the past years due to lack of funding. Most of these funds are being diverted to Space Launch System (SLS). SLS program is way overfunded, and NASA has stated clearly that they don't have any means of using those additional funds. Commercial crew program is likely to be delayed by years if not funded sufficiently. There is a petition ongoing to restore that funding.

Submission + - An origami paper-based bacteria-powered battery

jan_jes writes: Origami is the Japanese art of paper folding created by Akira Yoshizawa, which can be used to create beautiful birds, frogs and other small sculptures.

Last Year a team of engineers from MIT and Harvard has developed an origami flat-pack Robot[] which can fold itself and crawl away without any human intervention.

But now a Binghamton University engineer says this technique can be applied to building batteries, too. The battery generates power from microbial respiration, delivering enough energy to run a paper-based biosensor with nothing more than a drop of bacteria-containing liquid. This method should be especially useful to anyone working in remote areas with limited resources. The total cost of this potentially game-changing device is "Five cents".

Comment Re:Factor of 10 (Score 1) 77

Get real man. Shuttle might have cost a bit higher due to politics, but it was never going to be cheap - just as SLS is not going to be cheap. Shuttle should have been abandoned at least in 1986 when they realised that they forgot to put a launch abort system on it.

Over its lifetime, it has cost $209B. That is over $1.5B for each flight.

Hmm... may be it will look cheaper by 2025 when you are spending over $10B on each launch of SLS (It is expected to cost $41B for 4 flights by that time). Hopefully someone would have mercy and kill it before then.

Comment Re:How is this a shuttle? (Score 4, Informative) 77

ISRO never called it a shuttle. It has always been refered to as technology demonstrator (RLV-TD). Current experiment is termed RLV-TD HEX (Hypersonic flight Experiment). The ultimate aim is to develop an RLV named Avatar, which was originally announced over 17 years ago.

This particluar test flight should not be compared to US space shuttle. Better comparison would be X-43A or X51-A Waverider. As these have defence applications, the projects had been running between NASA and DARPA. Similarly, India's Avatar programme has also been shuttling between ISRO and DRDO (Defence Research & Development Organization).

The main feature of Avatar concept is an air breathing Scramjet engine. So far there hasn't been any great success in developing Scramjet engine. The longest one fired for 15 seconds on second flight of X-51A, while its first flight didn't run scramjet. India is nowhere near developing Scramjet in immediate future. But the current flight will test some preliminary technologies related to that project, specifically hypersonic reentry. I don't think this particular vehicle has any propulsion. Even the next two experiments planned on the series (LEX and REX) are planned without any rocket propulsion, but will use turbofan engine for landing. Actual powered flight would be on the SPEX, which will use Scramjet (Source:

Current test is a 100 crore INR (about 16 million USD) experiment. I am happy that ISRO is doing something to take this promising technology further. It may take another 20 years before actually seeing a scramjet engine in action, but that is ok. I would consider it as my tax money well spent.

Comment Re:Landing Pad (Score 2) 69

Landing on a barge (or ASDS) would still be needed for deep space missions like DSCOVR which didn't have enough fuel left to boost back the stage towards launch pad. The center core of Falcon 9 Heavy wouldn't have enough fuel as well, and will most likely land on ASDS, while other two booster cores go back to landing pad.

SpaceX is in fact building a second ASDS which will be used for launches from Pacific coast.

Comment Re:SpaceX and India? (Score 5, Informative) 91

This doesn't make a dent in cost effectiveness of Falcon 9 or PSLV.

Let us calculate per pound LEO costs for these vehicles:

ALASA: $1M / 100 lb = $10,000 / lb
Falcon 9: $61.2M / 28,991 lb = $2,111 / lb
PSLV: $20M / 7170 lb = $2,789 / lb

Tiny satellites at 100lb can easily tag along with bigger launches on these vehicles. Costs may be even cheaper for such secondary payloads or may even free in some cases. If SpaceX succeeds in first stage reuse, or ISRO per chance succeeds in RLV-TD plans, costs may come further down.

So ALASA sounds like a costly option for small satellites today and in future. But the technology as such may have potential if handled by a better managed private company that works on it as a commercial venture.

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