Please create an account to participate in the Slashdot moderation system


Forgot your password?
For the out-of-band Slashdot experience (mostly headlines), follow us on Twitter, or Facebook. ×

Comment: I don't see the logic here (Score 3, Insightful) 52 52

A launch site at latitude L can launch into an orbit of inclination L *or higher*. You can launch into a polar orbit from anywhere on the planet. You can only launch into an equatorial orbit from the equator. Equatorial sites have the advantage, not high latitude sites. (Also, the hemisphere doesn't matter. Something launched into low Earth orbit from 45 degrees south will be at 45 degrees north in about 45 minutes time.)

Some technicalities:
Yes, you can launch into one orbit then change plane to a lower inclination later - but doing so in LEO is very expensive. (I think the cheapest way to do it is to put yourself into a high eccentricity orbit, do the plane change at max distance from Earth, then recircularize your orbit into LEO.) ('expense' = delta-v.)
Launching from latitude L also can't launch into retrograde orbits closer than L to 180 degrees. E.g. from latitude +/- 30 degrees, you can launch directly into orbits with inclination between 30 and 150 degrees.
If you specifically want a 45 degree inclination orbit, I don't know whether launching due east from a 45 degree latitude is cheaper or more expensive than launching either NE or SE from an equatorial site. I suspect there is no difference.

Comment: The exact opposite of what Niantic should do (Score 2) 128 128

The entire point of portals is that they are located at physical locations that have historical or cultural significance.
The list of the top ten most historically and culturally significant sites in the whole world would include the concentration camps.
This is political correctness at its worst, where in seeking sensitivity it in fact hides atrocity.

Comment: Re:How about circuit boards? (Score 1) 266 266

OSH Park. Why even bother with the decades-old milling and/or toner transfer method? I get plated vias, soldermask and silkscreen.

Speed. I have an admittedly fairly nice dedicated pcb mill. I can make five revisions of circuit boards in a day, and then send the well-tested version out and wait a week to receive my beautiful soldermasked and silkscreened final revision pcb.

Comment: incomplete list of stuff we've printed (Score 1) 266 266

Mold for lost-PLA investment casting of complex intake manifold. Rat trap. (It was a very bright rat and wouldn't go near commercial traps.) Sewer system cutout plug. LCD bezel for the tachometer on my lathe. Same for the milling machine. Adapter for the PCB milling machine, to hook the metric vacuum output to my shopvac. Mounting bracket to hook a stepper motor to the back of the speedometer in my Little English Sportscar, that has never in its life until now had an accurate speedometer. Pogo pin test fixture for PCB testing. Bearing holders for a shaft hobbing mechanism for the lathe. LED diffusers for some task lighting in the shop. Outlet cover for an outlet combo that doesn't exist (sideways switches plus GFCI outlets in one box.) Power amplifier enclosure for automated test equipment. Fan shroud/grille. Adapter to mount LED lighting system on a microscope. Adapter to mount LED lighting system on the PCB milling machine. Replacement doohickey for a 6" digital calipers that had the little wheel that opens/closes the calipers break off. Adapter to mount 24" digital calipers to the back of the small lathe as part of a digital read out display. Adapter to mount Garmin 305 to an odd-size, odd-cross-section aero handlebar on my time trial bike. I could go on but that's probably enough for now.
I did most of the modeling in FreeCAD or HeeksCAD, by the way, with a little bit in OpenSCAD.

Comment: Overpressure in upper stage oxygen tank (Score 1) 49 49

Now he says "There was an overpressure event in the upper stage liquid oxygen tank. Data suggests counterintuitive cause."
"That's all we can say with confidence right now. Will have more to say following a thorough fault tree analysis."

Comment: How I saw it (Score 1) 49 49

Several minutes into flight, something that looked possibly like the Dragon capsule detached from the rocket and fell behind it. A few seconds later, the rocket disintegrated into fragments. The commentator on the SpaceX stream wasn't very informative (although their coverage was great up to that point, better than NASA's.)

NASA commentary has just confirmed that the vehicle has failed. (SpaceX have stopped streaming.)

Comment: Re:Maybe, maybe not (Score 1) 529 529

Now, there may actually be a very few people who do genuinely have the problem, but when you come to do the studies, you sample a large number of people. You do the statistics. You do not conclude that there is no link - studies like these cannot show that there is *no* link. You conclude - correctly - that there is no statistically significant link. But there still might (or might not) be a real problem for a very few people.

This is like people who claim they have ESP and magical abilities. If there were even ONE legitimate case, they could simply walk into a casino and repeatedly win multi-million dollar wins until every casino on the planet bans them.

All it takes is ONE "electrosensitive" who can consistently answer yes/no to whether an antenna is broadcasting. Much like ESP and other supernatural abilities, so far they do not exist.


The star of riches is shining upon you.