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90

'Starman' is a mannequin (store dummy) wearing a real SpaceX developed space suit that was a qualification unit, used in designing the space suit for the Commercial Crew program. During the SpaceX Grasshopper program, where they tested landing a first stage in McGregor Texas they mounted a dummy with a cowboy hat on the base of the Grasshopper vehicle. ...


79

Because linear increases in delta-v require exponential increases in mass, small changes to the assumptions you make about fuel tank structural mass and engine thrust-to-weight ratio start to make very large changes in the final size of the rocket. For example, if you're getting off a 3.6g planet with a 7-stage rocket, the difference between 88% fuel ...


66

The very first start of a new rocket is a risky endeavour. Since the system is put to test for the very first time as a whole, all kind of things can go wrong and chances are that the rocket doesn't make it into orbit. So a cheap, unimportant payload is needed for the first launch. You don't want to see something worth billions of dollars and having cost ...


50

Why not deliver something useful to the space station like a new living segment? Many, many reasons. A dummy payload is almost always used on the maiden flight of a new rocket. The risk of failure is too high to send anything of value as a payload. SpaceX cannot send something to the ISS just because they want to do so. They can only deliver cargo to the ...


29

I first need to know if starman is a real human or a robot. Starman is the name given to the mannequin/space suit occupying the driver's seat of the car. It is not human nor is it a robot. If he is a real human, how does he live? If it were human, the spacex suit is meant to be used pressurized. Details about the suit have not been provided other ...


27

Depending on your definitions, the contenders seem to be the US Space Shuttle, Buran, Apollo 17, or Skylab. Apollo 17 + S-IVB translunar 143 t? STS, maximum payload 115 t Discovery STS-82 106 t STS, no payload 90 t Buran + payload 87 t? Polyus 80 t? Skylab ...


25

The ISS solar array masts are launched collapsed in canisters, and run through a deployer mechanism to erect them as a long straight object. I see no technical reason why a much longer mast couldn't use this system. For details see this question and answer: How do the booms on ISS (and other spacecraft) extend and retract?


24

First, let us look at the rocket equation: $$\Delta v=\ln \left(\frac{m_0}{m_f}\right)v_e$$ That tells how much a rocket can change its velocity (the $\Delta v$). The requirements for reaching a higher velocity for a minimal orbit would increase on your heavier Earth. (For constant density it is proportional to the radius.) How can we increase the $\Delta ...


23

Long rigid structure can be transported as raw material for fabrication in space, in the same way that continuous rain gutters are made. In the pictures below, you can see a machine that creates the rigid rain gutter from a compact roll of sheet metal. The method is provides for compact transportation, only limited by the compacted size and weight of the ...


21

SpaceX published numbers on their website near the bottom of the page. I snapped an image to show here, since their formatting is prettier than I can do in Markdown. You can see that it can do pretty much any of the missions. Now you could probably do a better job with a third stage/kick stage, because while the second stage Merlin-1D Vac has a lot of ...


20

According to Wikipedia, Saturn V could launch 48600 kg to translunar injection. From there, you need about 2410m/s of ∆v to soft-land on the moon. Let's take a little additional fuel for safety margin and call it 2700m/s. Per the rocket equation, assuming you're using a rocket that uses storable hypergolic propellants with a specific impulse of 312s (...


19

The JWST is made to fold up, to fit inside the standard fairing. You can sort of see this in your image, 3 mirror segments are visible (the hexagons in the middle), other segments are viewed side-on and aren't visible. Folding animation Time lapse showing the folding during assembly


19

What is known: SpaceX issued a statement saying that the Falcon 9 performed as intended An object was seen with spinning plumes that is assumed to be a Falcon 9 upper stage post-thrust fuel dump. This occurred at about 2 hours, 15 minutes after launch, over Africa. The official timeline/ press brief The customer of Zuma was an unnamed US Government agency. ...


19

88! PSLV-C37 launched 88 identical satellites into a sun-synchronous orbit. These satellites were for an imaging company called "Planet Labs". Technically the only ones that were identical were the CubeSats (Which were named Doves) but they were launching 4 other types of satellites from this launch too. The rocket launched Cartosat-2D, a few other ...


17

Best way to do this could be to research, develop and send a "3D tube printer satellite" to low Earth orbit, and feed it with whatever material in liquid, powder or filament form, which will not require any special attachement or design modification to existing rockets, since it can fill any shape of a given volume. For instance one 0.5 km long tube, 10 cm ...


16

First of all, let's look at what the limitations are for placing objects in a rocket. The object must be aerodynamic, such that it does not influence the launch characteristics. You need to easily be able to get the objects separated from the rocket. The thrust must happen at the bottom, for maximum efficacy, straight down, and the center of gravity should ...


16

Here's a Map to the Solar System. It details, roughly how much $\Delta v$ you need to get from one place to the next. You can take the rocket equation to quickly calculate your Fuel fraction for any given $\Delta v$. We take the basic form ($m_0$ starting mass; $m_1$ final mass; $v_\text{e}$ effective propellant exit velocity) $$ \Delta v = v_\text{e} \ln \...


16

The numbers on the Wikipedia page are a little messed up, so you can't do apples-to-apples comparisons. You'd need to go to the actual payload planner's guides to see what the performance is to what orbits. Here are the guides: Delta IV Launch Services User's Guide Proton Launch System Mission Planner's Guide A Proton launch to a LEO with the launch ...


16

Update: February 24, 2018 The 'Disco Ball': Created by Rocket Lab founder and CEO Peter Beck, the Humanity Star is a geodesic sphere made from carbon fibre with 76 highly reflective panels. It spins rapidly, reflecting the sun’s rays back to Earth, creating a flashing light that can be seen against a backdrop of stars. Visible for a few seconds, every 90 ...


16

When SpaceX launched the Falcon 1, it took them 4 times to successfully orbit the Earth. The most similar rocket to Falcon Heavy, in terms of the number of engines, the N1, made 4 attempts to reach orbit, all of which failed. The more engines, the more complex things are. The chance of a failure is extremely high on this launch. No one would be willing to ...


15

Suborbital sounding rockets cost about 1/100 as much as an orbital launcher. Black Brant XII, one of the most advanced sounding rockets in use, can take 100-400kg payload into space for \$600K. For a Falcon-9-based sounding rocket approach to make any sense, you'd have to describe a single payload that delivered as much science as 100 individual 100kg ...


14

The shuttle was certainly one of the more mass-efficient orbital launchers, but it's a more complicated question than it might seem at first. The shuttle orbiter is ambiguously part of the launcher and part of the payload, so it's simply not possible to compare it apples-to-apples against other launchers. For "pure" payload that's going to stay in orbit ...


13

Launching on a risky booster, is risky. You can define a risky booster as: First launch of a new booster. Return to flight after a failure. Booster with record of failure So you feeling lucky punk? How much development money are you willing to risk on any of those cases? Why did ISRO take the risk on the GSLV launch and Angara5 won't? I would assume ...


13

Pearson's answer is technically correct for smaller satellites, which are flying pickaback as secondary payloads. But it is missing the big primary payloads. So for the sake of completeness, have a look at different Ariane 5 configurations: Different types of upper section for Ariane 5. Credits: Esa/D.Ducros A rather common strategy is to 'pile' two or ...


13

Following the theme of "depending on your definitions" one could also consider the Polyus spacecraft launched in 1987. The mass of the spacecraft was 80 tonnes. Thoughts about definitions: slightly heavier then Skylab, less than the SIVB/LM/CSM stack it didn't get to a stable orbit, perhaps to 155km. The Energia vehicle functioned correctly and the ...


13

I have collected a list of orbital mass simulator launches and there fates: Antares A-ONE, mass simulator Orbit: approximately 150 by 160 miles (240 km x 260 km) with an inclination of 51.6 degrees Fate: Burned up in atmosphere Falcon 9, Dragon Spacecraft Qualification Unit (basically a mass simulator) 249.5 kilometers (155.0 mi) x 252.5 kilometers (156....


12

Payloads come in different shapes and sizes. To put them on a specific launch vehicle, you need to either design the payload to fit perfectly onto the rocket or you need some sort of adapter to mount it in place. It's also common to launch multiple payloads with a single launch, so you need some mechanism to separate the different payloads and release them ...


11

There are several issues here. Volume, and mass for return through the atmosphere. There is of course the next question of, how do I get this object? Currently Soyuz can return about 100-150 lbs of mass. Volume wise it is very limited, since the descent capsule is very cramped and needs room for three cosmonauts. Dragon from SpaceX is the only other ...


11

A thin pole .5 km long is easier said than done. A scaffolding pole (4 m long, 4 cm diameter) may seem rigid, but link a few end-to-end and the resulting pole will be flexible. If you attach it to the outside of a rocket, it'll start wobbling under the aerodynamic loads. You can combat this by making the diameter larger, but to support a pole 500 m long ...


11

480,000,000!† †Depending on how you define satellite. I think Project West Ford is the current record holder, with 480,000,000 individual satellites. Well technically 480,000,000 copper dipole antennas, designed to act as an artificial ionosphere. Here is a photo of a few of the dipoles:


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