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One good reason to have a different name is to do away with the space-based-arms-race-provoking nature of "Space Force," which likely contributed to India being emboldened to carry out this test.

If any country feels that they absolutely must have a space-based weapons program despite all the good reasons not to, they should keep it top secret. The Soviets were smart enough to know that:

https://www.popularmechanics.c...

https://en.wikipedia.org/wiki/...

Today's Russians are still smart enough to know this:

https://space.skyrocket.de/doc...

And before Trump, the US was too:

https://en.wikipedia.org/wiki/...

https://en.wikipedia.org/wiki/...

Space-X is alive only because of the money it got upfront from NASA for launches they may or may not deliver.

This is just not true. SpaceX has had a wide variety of non-NASA customers. Falcon 9 launched 18 times in 2017, which is 20% of all launches globally and about 2/3rds of all US launches , and the vast majority of those launches were not for NASA http://space.skyrocket.de/doc_chr/lau2017.htm. Moreover, SpaceX has delivered cargo launches to the ISS repeatedly for NASA, and with the exception of one launch in 2015, all of those have been successful.

Nowadays there's the option of a constellation of micro-satellites like Earth-i's Vivid-i that use off-the-shelf components, get reasonable resolution (sub 1m), and only cost a few 10s of millions each to buy and launch. Many nations could afford to maintain a large enough constellation of those to provide blanket coverage - Earth-i reckon 15 of them can image most places on Earth 3 times a day. This stuff is only going to become cheaper.

For the second time pea brain, citation needed (i.e. how do you know it's not 14T?).

I know it's not 14 mt because it weighs around 4 mt. Tell me again, why am I supposed to do your homework for you?

One of the most sketchy wikipedia entry ever, no inline citation, no equations...you didn't author this epic entry yourself did you Kyosuke?

No, I did not. Besides, unless you're completely incompetent, I'm sure you can whip up a simple simulation of the influence of gravity drag, in, say, Octave or a similar environment. Even a one-dimensional case is educational. A highschooler with a bit of intuition grasps the idea.

But I'm wondering why you didn't expound on the fact that 7T+30%=9T (only factoring the 30% on LEO missions where landing legs were attached) is a pitiful 1/3 of the 25T "heavies" SpaceX is pounding it's man boobs against?

I have no idea where you got "7T" from; the figure against which the margin is computed isn't 7 mt. It has nothing to do with LEO missions either.

Perhaps you can enlighten the uninitiated on how 10% fuel capacity increase, translates to 70+% payload increase, with the same rocket engine efficiency (specific impulse)?

It's not a 70% increase; it's about a 30% one (from about 6.3 mt to about 8.2 mt for the expendable GTO figure). And it's perfectly explainable through Tsiolkovsky's equation. For a ballpark figure, just assume 90 mt of propellant, 5 mt of dead weight and 5 mt of payload, and increase the propellant by 15% for the stretched-and-densified fuel load and recalculate payload for the same mass ratio. It's even invariant of Isp; you're assuming identical delta-v's for the second stage operation as a reasonable approximation (first stage got improved slightly too and the separation conditions change only a little). The dead weight is substantial for the F9's second stage. Whenever the payload is lightweight and the trajectory is a high energy one, the fuel load makes all the difference. Again, simple fractions you can surely do yourself.

They're not using the AR 2-3. That was part of the original specs from before DARPA took over the program. It's confirmed to use hydrazine now, but the actual engine is uncomfirmed. See http://space.skyrocket.de/doc_sdat/x-37.htm

Mexico has, er, "had" a satelite?? I found that surprising.

I was surprised too and wondered why they just didn't contract out to buy time on someone else's satellite since a billion dollars over the 15 year projected lifetime of the satellites will buy a lot of satellite time. Turns out it's for "National Security Needs", which I guess means they don't trust anyone else to provide service, though if the USA reneges on a deal to provide national security satellite services to them, Mexico has far bigger problems to worry about.

The NSA is going to intercept their data whether they have their own satellite or not -- it was bought from Boeing, so the NSA will certainly have full access to the Satellite during construction.

http://space.skyrocket.de/doc_...

From the link provided above:

The payload generates navigation signals at L5 and S-band. The design of the payload makes the IRNSS system inter-operable and compatible with GPS and Galileo.

VLBI fans, rejoice ! Really, after the Japanese VSOP mission, it has been a long wait for this one (first proposed in the 1980's). Together with antennas on the ground, RadioAstron should provide the highest resolution of any human telescope, anywhere, at any wavelength. (Here are some more technical details.)

The USA pioneered the use of this technology (the first space VLBI, in the 1980's, used a NASA TDRSS communication satellite that was underused after the Challenger disaster), and Irwin Shapiro suggested putting VLBI terminals on the Moon well before that, but here is another case where the USA can't seem to actually get its stuff into the orbit.

Skynet went online on 1969. It continues to serve the UK military to this day. They're up to series 5, but it doesn't seem self-aware yet.

... THIS is tiny!

The proposed bigger model, the Falcon 9-S5, is comparable to the modern Atlas V.

With three primary differences:

1. The 9-S is intended to carry up to 23% more cargo to LEO.
2. The 9-S will be man-rated with full "engine-out" features.
3. The 9-S is intended to be somewhat reusable, thus helping keep the costs down.

These sorts of features are a BIG DEAL in the rocket industry.

About 2x the price the new guys claim, but then, the Atlas is a proven product.

Tis' true. That's why we're all holding our breath to see if Musk delivers.

But the commercial launch market has collapsed. Iridium is done, and nobody wants to launch that many sats again.

I don't know where you get this idea. There have been healthy numbers of sats going up in recent years to support all kinds of network infratructures. Here's a list of past and planned launches. Looks pretty healthy to me.

You may be thinking of the slowdown in the market caused by the loss of the Challenger. With the Shuttle out of commission, the market suddenly realized that it had no other way to get to space. Thus the commercial launch business was forced to retool to build rockets like the Delta and Atlas. Russian rockets also became popular, especially after Boeing and Lockheed started buying them up.

In any case, Musk is aiming for manned space travel. The commercial launches are a side business to help support that goal. He wants to go to Mars.

These types of satellites are becoming increasingly more popular and this type of satellite is considered one of the leading growth sectors for commercial satellites in the upcoming decade.

These types of satellites are becoming increasingly more popular and this type of satellite is considered one of the leading growth sectors for commercial satellites in the upcoming decade.

These types of satellites are becoming increasingly more popular and this type of satellite is considered one of the leading growth sectors for commercial satellites in the upcoming decade.

These types of satellites are becoming increasingly more popular and this type of satellite is considered one of the leading growth sectors for commercial satellites in the upcoming decade.

Sorry, you're dead wrong.

The Soviets eventually came to the same conclusion, only after blowing the big rubles on Almaz and military Salyuts.

Incidentally, the first successful US launch after Challenger was an SDI experiment that used guidance systems from existing guided missiles. Although it was about as rushed as the Polyus battle station you reference, it didn't require major gymnastics to achieve orbit, and provided Reagan with a negotiation advantage over Gorbachev... although I don't think he fully realized the size of it. For a change, the Russians were in the position of attempting to field a system we could all too easily counter, given that the Delta 180 SDI test articles were mostly off the shelf, and could be cheaply integrated and lofted by the trainload, had the need arisen.

According to their fact sheet (pdf) the mission will be completely autonomous. The DART spacecraft even has collision avoidance algorithms. It seems that this spacecraft was designed only to repair one particular satellite (MUBLCOM), although several of this satellite currently exist. Anyone know if the services of this DART spacecraft can only be used once, or can it travel the LEO repairing all MUBLCOM's it comes in contact with?
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NoVa Underground: Where Northern Virginia comes out to play. This means you Fairfax County

What you actually mean is the AERCam/Sprint tested in the STS-87. Strange they didn't mention it anymore, even though there seem to be plans of an improved version.

Is this nano-sputnik the same as the ones released by MIR in 97?
They are about the same mass and size.

http://www.skyrocket.de/space/index_frame.htm?http ://www.skyrocket.de/space/doc_sdat/sputnik-40.htm

I tried submitting a story on SpaceX a couple of weeks ago, but it was sadly rejected. Here's the text of the submission, along with some other interesting info:

Spaceflight Now has an article on SpaceX, a low-cost space launch company started by PayPal co-founder Elon Musk (he is no longer with PayPal). The article describes SpaceX's small-size Falcon I rocket, scheduled to launch a military imaging satellite on its maiden flight in March, and their medium-size Falcon V rocket, scheduled to lift a prototype Bigelow inflatable space habitat next year. Interestingly, the Falcon V has enough capacity to lift a Gemini-style capsule with 5-6 people to orbit. Both rockets have per-pound launch costs approximately one-fifth that of comparable rockets. Long-term plans call for evolving the basic design to heavy-lift and super-heavy lift rockets, assuming SpaceX survives its legal battles with defense giants like Northrup Grumman. Musk believes that ultimately a launch cost of '$500 per pound or less is very achievable' (compared to $10,000 per pound for the Space Shuttle). Elon Musk is a member of the Mars Society, and started SpaceX after he realized that current launch costs would be a large barrier to his plans for a philanthropic mission to put an experimental greenhouse with food crops on Mars.

This radio interview with Elon Musk from 2001 is pretty neat, and has some information I haven't seen elsewhere.

Yep, I agree.

The satellites I used to work on were $1 mil, and the rockets were $10 mil*, with the result being an extremely simple LEO low bandwidth store-and-forward satellite. The mars rover is definitely 36x cooler!

(* discount price because it was an untested rocket. It blew up, of course! The diamond-looking emblem on the top of the rocket? it's a "GEM" for GEMSTAR- "G"lobal "E"lectronic "M"ail)

"there is a case where a failed launch resulted in radioactive material"

There's a complete list of nuclear powered spacecraft and their failures here. The worst one was the Russian Kosmos 954 spy satellite that re-entered from Earth orbit and spread radioactive particles from the reactor core over a wide area of western Canada. It was bad, and required a huge cleanup effort, but it was hardly a doomsday scenario.

Voor diegene die dit nog niet kunnen volgen:

Telstar 4: Een TV sataliet (Afbeelding hier maar de echte slashdotter kan hem in het echt zien zolang je maar weet Waar en waneer)

"CW carriers up on 11700 MHz V & 12200 MHz H": Een CW carrier is niet zomaar een draaggolf, het is een draagolf met een morsecode er op! (foei mister berg CW staat hier voor continuous wave), de V en de H geven de polarisatie aan.

Loral Skynet : Uitbater van de Skynet satalieten die een groot deel van de wereld van TV voorzien.

"orbital slot": Een locatie op een baan boven de evenaar (voor geostationaire satalieten)

I assume Wouter (The parent poster) and I are both equally delighted te be have found a home away from tweakers.net, which carries mainly bad translations (To dutch for those still wondering) of slashdot items... I better shut up now, voor ik een bende power-koeien achter mij aan krijg.

In 1991, DSI (now bought by Orbital Sciences) built a series of similar-sized satellites for Darpa, named Microsat aka SCS.

These were pretty simple - if I remember correctly, they didn't have much of an attitude control system. You can see tell this from the picture because the solar cells on all sides, and the antenna shown (one of two) is relatively omni-directional. I think they had some compressed gas for station keeping (they were supposed to be evenly spaced around the orbit) and/or creating spin ... it was flying in formation, but not too sophisticated.

What troubles me is that the SPHERES have no solar cells. True, electronics take less power now, and LiIon batteries store more energy than our old NiCds, but radios will still take a few watts. I wonder what the life of their two test satellites will be, or if they just forgot to include the solar cells.

We fully qualified 8 of our Microsat satellites, but only lauched seven. The left-over real satellite was a great marketing tool and cool show and tell piece to bring to schools.

Pegasus is a great. You don't even need to own the L1011; the first pegi were launched from a borrowed B52.

If you check out their record, major problems in 5 of the first 10 launches isn't quite the reliability record I want for a manned flight. Especially since the x-prize requires 2 back-to-back flights - something that didn't happen until flights 7 & 8. The contest also requires reusability, but that's another story.

p.s. I shared an office with the original glomr... click click click of the tx/rx relays. Ok, it wasn't an office: they put the intern in the lab.