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In 2017, twenty-nine orbital rockets were launched from the US. Nineteen of those were a Falcon 9.

http://spaceflight101.com/2017...

These kinds of errors are not just related to Russia.

Mars Climate Orbiter probe lost due to Math error:
English to Metric math conversion error
https://edition.cnn.com/TECH/s...
https://mars.nasa.gov/msp98/ne...
http://articles.latimes.com/19...

ExoMars Schiaparelli lander crashed due to failure to recognize the proper height.
http://spaceflight101.com/exom...
https://www.forbes.com/sites/b...

I found another reference in English at http://spaceflight101.com/shijian-17-rendezvous-with-chinasat-5a/: "and debuting a Hall-Effect Thruster system for use on future Chinese GEO satellites"
 

Hall effect thrusters are not related to the EMDrive, nor they are reactionless: https://en.wikipedia.org/wiki/Hall-effect_thruster

Reading around in particular on this mission (SJ 17), you should have been upmodded instead. The test of this drive isn't the main mission...the main mission is probablly more along the lines of "in space Eavesdropping":The observed maneuvers provide clear clues on the intent of the SJ-17 mission as a Space Situational Awareness pathfinder, testing navigation technologies to link-up with resident objects in Geostationary Orbit – getting sufficiently close to capture optical imagery of the object and shadowing it at close distance to intercept its uplink communications.

This is a test to see if they can maneuver close enough to intercept signals. Today their targeting a Chinese orbiter...but once this tech is ironed out it will probably be set up for rapid in-orbit deployment against non-Chinese systems. I see a use of having a sat like this sit in GEO orbit nearby potential targets, but not "too close" until mission green-go. They will then use whatever electrical engines (EMDrive, conventional ion, whatever works) to get into uplink intercept range. I can even see, in case of an actual conflict, "sacrificing" and taking out a comsat.

The whole EMDrive is just icing on the cake here; it's just a means to an end for in-orbit maneuvering.

I'm pretty sure I remember you have previous posts calling people "space nutters", and are pretty rabid in attacking anything outside mainstream NASA. The claim that CAST has nothing just because the English version has nothing means nothing...unless you've gone through the Chinese language version and can prove the two sites contain the same information.

I found another reference in English at http://spaceflight101.com/shijian-17-rendezvous-with-chinasat-5a/: "and debuting a Hall-Effect Thruster system for use on future Chinese GEO satellites"

Digging into this via Google Translate does provide far more information. The information your claiming doesn't exist actually DOES exist, on the stdaily.com article. It's just all in Chinese, so you have to put some effort in to translate it. My link is at translate.google.com and https://translate.googleusercontent.com/translate_c?depth=1&hl=en&rurl=translate.google.com&sl=auto&tl=en&u=http://digitalpaper.stdaily.com/http_www.kjrb.com/kjrb/html/2016-12/11/content_357005.htm%3Fdiv%3D-1&usg=ALkJrhhkYPDNKL_9BxSu6OAkt5KIHsse9Q but I don't know if this link will work for anyone else.

Using Google page translation:

Chen Yue said: "We use the classic electromagnetics and electrodynamics to design several different shapes of thrusters, theoretical analysis can generate thrust thrust, and through the test of the thrust, the results in line with theoretical analysis. Science and Technology Daily Beijing December 10 " Roger Xiaoe in an interview was also asked this "eternal" problem, he made it clear that the EM engine does not violate Newton's law of mechanics: "EM engine in a direction to generate propulsion, if circumstances permit, will In another direction, the momentum of the whole process is conserved. "This explanation is considered ambiguous.

"We have successfully developed several specifications of several prototype principle, the establishment of experimental verification platform to complete the milli-level micro thrust measurement test, through several years of repeated tests and the corresponding interference factor investigation test, confirm that the type of thruster Thrust exists. "Chen Yue introduced that they have completed the test device can be used for flight test development, is in orbit verification.

"This technology is currently in the latter stages of the proof-of-principle phase, with the goal of making the technology available in satellite engineering as quickly as possible," said Li Feng, chief architect of the China National Space Technology Institute's communications satellite division. , The principle prototype volume, thrust is small, require special engineering methods, optimize the cavity design, improve the cavity quality factor, reduce the loss, the microwave energy is more effective for generating thrust. At present, the thrust is measured to micro-cow level to millennial level, at least to improve the level of 100 cents or even cattle-level satellite can be used for attitude control, orbit and so on.

More dis-information. The kerosene for the Full Thrust version is chilled to -7 degrees centigrade , boosting its density by 2.5 - 4.0 percent.

Or how he'll do what NASA doesn't know how to do (land such a large vehicle).

The Falcon 9's first stage weight is estimated to be about 25 tons when empty. That's the stage that returns to Earth (or sea) and lands.

The space shuttle weighed about 82.5 tons when empty. Mars' gravity is about 38% that of Earths. 82.5 tons * 38% = weight equivalent to about 31 tons. So aside from inertia, the practice Space X has been getting landing the Falcon 9 translates almost exactly into landing a space shuttle-sized craft vertically on Mars.

Agreed that radiation is a huge problem. I think oxygen generation and recycling water and waste materials are equally daunting problems (it's unrealistic to carry enough oxygen, water, and CO2 scrubbers for a 2.5 year mission). We've just begun tackling those issues.

SpaceX, and the people in this thread, are comparing the vehicle cost to fuel cost, which is kinda cheating. It's not the cost of the fuel that matters, it's the cost of building the vehicle larger to hold that fuel -- and the fuel needed to launch that fuel -- that matters. So let's do the math!

Most data taken from http://spaceflight101.com/spac...
Basic info:
Stage 1: 23 tonnes structure, 400 tonnes fuel
Stage 2: 4 tonnes structure, 93 tonnes fuel
Payload: 13 tonnes

When launching, the first stage burns all 9 engines at full thrust for two and a half minutes. The re-entry burn and landing happen on a single engine, and from eyeballing the videos (including this one that shows the re-entry burn) appear to take about 30 seconds total. Assuming all burns are near full thrust (which is the best way to do it), that means the landing burn takes about (1/9) * (0:30 / 2:30) = 2% of the first stage fuel. Let's double that to 4% to provide a generous safety margin: that works out to about 400 * 0.04 = 16 tons more fuel.

This fuel is carried up to the moment that the second stage separates, so it subtracts from the mass of the second stage. Second stage plus payload weighs 110 tonnes: without the landing fuel, you could have scaled that up to 126 tonnes, a 15% increase.

So, landing the first stage reduces the payload SpaceX can launch, and thus the money they earn, by about 15%. In exchange, they recover about 75% of the cost of the launch hardware. So it's worth doing, even after you subtract off the cost of recovery and refurbishing. Maybe not the game-changer Elon Musk wants it to be, but it's a win.

Don't forget through, that after the separation you're basically flying just an almost-empty fuel tank. It's WAY lighter after burning up most of its fuel and shedding the first stage, so the actual amount of extra boost that could be given to the second stage isn't nearly as large as you might imagine. Also, the vast majority of the 1st-stage fuel is "wasted" fighting gravity and air resistance, which are not major problems for the more leisurely (and downward) return trip.
Consider:
F9v1.1 1st stage = 23Mg inert mass + 396Mg of fuel
F9v1.1 2nd stage = 4Mg inert mass + 93Mg of fuel
http://spaceflight101.com/spac...
Assuming the first stage has burnt up most of its fuel prior to separation, it's only about 19% of the total mass, and only about 4.4% of the pre-launch mass. Much easier to return home than get to that point in the first place.

The extra fuel could still be used to give the second stage a bit more of a boost, and is planned to do so for higher/heavier launches where every little bit helps, but the first stage isn't really optimized for operating in vacuum, so the available thrust will be less than would be available for a return flight.`

There is a listing and pics of the lost cargo here.

The Dragon SpX-7 mission was to deliver supplies to the International Space Station and return cargo to Earth. Dragon remains the only visiting vehicle of ISS that can return a significant mass of cargo to the ground, aside from the crewed Soyuz spacecraft that can ferry a few dozen Kilograms of return items back to Earth along with its three crew members. The SpX-7 mission will carry 1,952 Kilograms of cargo to the Space Station and return 675 Kilograms to Earth at the conclusion of its five-week mission.

Crew Supplies - 676kg
Systems Hardware - 461kg
Science Cargo - 529kg
Computer Resources - 35kg
EVA Equipment - 166kg
External Payloads - 526kg

Interesting to note that part of the science cargo was the Meteor study. The Meteor study, going by the full name of ‘Meteor Composition Determination,’ was to be the first of its kind to be deployed in space, solely focused on the analysis of meteors entering Earth’s atmosphere and pin-pointing their composition through their optical emissions when burning up in the atmosphere. The original Meteor hardware was expected to arrive aboard the International Space Station in October 2014 on the Cygnus Orb-3 resupply craft that unfortunately was lost in a launch failure of its Antares launch vehicle just seconds after lifting off. Coincidence or someone really does not want this study to go ahead.

There is a listing and pics of the lost cargo here.

The Dragon SpX-7 mission was to deliver supplies to the International Space Station and return cargo to Earth. Dragon remains the only visiting vehicle of ISS that can return a significant mass of cargo to the ground, aside from the crewed Soyuz spacecraft that can ferry a few dozen Kilograms of return items back to Earth along with its three crew members. The SpX-7 mission will carry 1,952 Kilograms of cargo to the Space Station and return 675 Kilograms to Earth at the conclusion of its five-week mission.

Crew Supplies - 676kg
Systems Hardware - 461kg
Science Cargo - 529kg
Computer Resources - 35kg
EVA Equipment - 166kg
External Payloads - 526kg

Interesting to note that part of the science cargo was the Meteor study. The Meteor study, going by the full name of ‘Meteor Composition Determination,’ was to be the first of its kind to be deployed in space, solely focused on the analysis of meteors entering Earth’s atmosphere and pin-pointing their composition through their optical emissions when burning up in the atmosphere. The original Meteor hardware was expected to arrive aboard the International Space Station in October 2014 on the Cygnus Orb-3 resupply craft that unfortunately was lost in a launch failure of its Antares launch vehicle just seconds after lifting off. Coincidence or someone really does not want this study to go ahead.

There was zero actual explosives in there and there was a showy, but mostly harmless fuel combustion which does not qualify as "explosion". Seriously, they do this in the movies because it looks impressive and at the same time does very little actual damage.

The Falcon 9 does have a Flight Termination System to destroy it if it goes off course, so there may still be explosives on the rocket when it is landing.

The recoverable version (F9R) has a set of cold gas thrusters. Other than that, not much is known. See this page

Lots more details describe in this article: DSCOVR Mission Updates. One interesting information is that landing burn in only 28 seconds. That's all it takes to slow down from the terminal velocity down to 0 while performing the final guiding maneuver to the bulls eye.

Just pointing out that SpaceX's manned Dragon capsule won't have an escape tower; the launch escape system is a set of eight SuperDraco thrusters, which will also be used for soft ground landing after normal flights.

It wouldn't take that much effort to detect the laser. According to this it's literally just a telescope with a secondary mirror. Running at 137 watts even in lunar orbit? That's going to be a tough sell on more distant missions. Cassini / New Horizons have a power budget of less than 300 watts.

http://www.spaceflight101.com/iss-expedition-38-us-eva-25-updates.html

are playing catch up in the space race, they are catching up pretty quickly.

Chang'e-3 is not playing catch up - its doing many things that "west" has never done. First, only two space agencies have sent probes to land on lunar surfacce before. US never sent a teleoperated rover. Russians did, but 40 years ago with much older set of instruments.

It also carries multiple scientific instruments that have never been used on the lunar surface before ( obviously, because it has been 37 years since anyone bothered to go there ) . Namely, it has a radar underneath it that is intended to scan deep under the surface - this has never been done before. Second, it carries a telescope, which will for the first ever telescope landed on another planetary body.

See here for details : http://www.spaceflight101.com/change-3.html

Some, but not all of it. http://www.spaceflight101.com/goce-re-entry.html : With its fins and aerodynamic shape, GOCE will maintain a stable position in orbit as it approaches entry. During entry, the spacecraft will likely remain in that position for the initial phase of re-entry until it breaks up. Following the destruction of the spacecraft, most of its components will harmlessly burn up in the atmosphere. However, it is known that about 20 to 40% of a re-entering satellite's total mass reach Earth's surface. Dense components of satellites usually impact 800 to 1,300 Kilometers downrange from the Orbital Decay Point. Their journey back to Earth is strongly influenced by atmospheric properties like crosswinds that play a major role during atmospheric descent.

It's not accurate to say that the Dragon will be automatically docking with the ISS, since the Dragon doesn't support automated docking yet. Rather, it very slowly approaches the station, holds steady at about 10m, and then the crew (or mission control in Houston) spends hours operating a robotic arm to grab it and bring it in.

As others have pointed out, NASA has the final say over whether the Dragon can even come within a kilometer of the ISS.

The initial approach during the COTS-2 demo was 0.24 meters/second according to this link and this link, and the final approach from 30m is even slower.

I'd imagine that the ISS could manage to avoid an object traveling towards it from 30m at roughly the speed of a tortoise, considering that most other dangerous objects in space are traveling much faster.

That's not to say that the thrusters couldn't misfire at just the wrong moment, but considering the care taken in the approach, it's not like they're just aiming it in the direction of the ISS and hoping for the best. It'd have to be a failure that didn't manifest at all until close to the last second, which would be extraordinarily bad luck.

It hit either the Indian Ocean or in China / Myanmar: http://www.spaceflight101.com/rosat-re-entry-information.html

It re-entered sunday 23rd between 1:45 and 2:15 am UTC (22nd 9:45 - 10:15 pm EDT): http://www.spaceflight101.com/rosat-re-entry-information.html

Nope. The Canada landfall story turned out to be a hoax. It landed in the Pacific between Hawaii and the west coast of the US, according to STRATCOM. See here.