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156 votes
Accepted

How much bigger could Earth be, before rockets wouldn't work?

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 ...
Russell Borogove's user avatar
94 votes
Accepted

Is Starman in the Tesla Roadster a real human?

'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 ...
geoffc's user avatar
  • 79.6k
67 votes

Why is the first launch of Falcon Heavy sending a car instead of something useful?

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 ...
DarkDust's user avatar
  • 12.5k
51 votes

Why is the first launch of Falcon Heavy sending a car instead of something useful?

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 ...
David Hammen's user avatar
31 votes

Is Starman in the Tesla Roadster a real human?

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 ...
Adam Davis's user avatar
  • 1,103
25 votes

How would a long pole be transported to space?

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 ...
Organic Marble's user avatar
25 votes

Is it possible to build a rocket with 2kg payload?

The SS-520-5 rocket from Japan is probably as close you can get with 4kg to orbit. Height: 9.54 meters Weight: 2600 kg Diameter: 52 cm
lijat's user avatar
  • 1,778
23 votes

How would a long pole be transported to space?

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 ...
Jim's user avatar
  • 331
21 votes
Accepted

How can the 6.5 m primary mirror of the JWST fit inside the 5.4 m fairing of Ariane 5?

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 ...
Hobbes's user avatar
  • 128k
21 votes
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What was the outcome of the launch of ZUMA by SpaceX, to the best of the public's knowledge?

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. ...
PearsonArtPhoto's user avatar
  • 121k
21 votes
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Can the Falcon Heavy handle deep space missions?

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 ...
geoffc's user avatar
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21 votes
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What is the largest number of identical satellites launched together?

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 ...
Magic Octopus Urn's user avatar
20 votes

Payload capacity of a rocket

The short answer is: Tsiolkovsky rocket equation. You need some velocity to achieve some position (an orbit or a body) in space. Farther a position - more velocity. More velocity - more propellant ...
Peter Nazarenko's user avatar
18 votes
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Has any payload been as silly, as the Falcon Heavy's Tesla Roadster?

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 ...
Rob's user avatar
  • 3,276
17 votes
Accepted

Where are all those blocks of steel and concrete now?

I have collected a list of orbital mass simulator launches and their fates: Antares A-ONE, mass simulator Orbit: approximately 150 by 160 miles (240 km x 260 km) with an inclination of 51.6 degrees ...
Mark Omo's user avatar
  • 5,291
17 votes

Payload capacity of a rocket

It perhaps become clearer when stating what rockets do. They change velocity. In space terms, that's delta-v. A rocket stage can only change your velocity some limited amount. Different targets in ...
SE - stop firing the good guys's user avatar
16 votes

Using large orbital launchers as sounding rockets. What are the opportunities and challenges?

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 ...
Russell Borogove's user avatar
16 votes

Why is the first launch of Falcon Heavy sending a car instead of something useful?

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 ...
PearsonArtPhoto's user avatar
  • 121k
14 votes

How much bigger could Earth be, before rockets wouldn't work?

note: I've accepted an answer 2.5 years ago. This paper was published recently so I thought I would add this supplemental answer since it may be an interesting reference for future readers. The Space....
uhoh's user avatar
  • 149k
14 votes

What is the largest number of identical satellites launched together?

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 ...
DarcyThomas's user avatar
13 votes

Was the Space Shuttle the most efficient orbital launcher, based on the launch/LEO mass ratio?

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 ...
Russell Borogove's user avatar
12 votes
Accepted

Why was the Energia’s payload capacity to lunar orbit greater than its payload capacity to geosynchronous orbit?

Your assumption is incorrect, the answer is pretty straight forward: It has less payload to geo-stationary orbit than to a trans-lunar trajectory, because the latter takes less delta V. The burns for ...
ANone's user avatar
  • 3,442
11 votes

How would a long pole be transported to space?

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 ...
Hobbes's user avatar
  • 128k
10 votes

What does it take to make a spacecraft able to launch on any out of several different launcher types?

The physical adapter is the easy part. These have standard dimensions. Commercial launch providers were quick to realize it'd be advantageous to offer compatibility. E.g. the Ariane 5 payload fairing ...
Hobbes's user avatar
  • 128k
10 votes
Accepted

What payload was expected for the 2018 Mars Dragon flight ("Red Dragon")

Aviation Week seems to be the best source right now. A few interesting bits: NASA is spending up to $30 million in support, mostly to help gain information for EDL on Mars. A photo might be taken ...
PearsonArtPhoto's user avatar
  • 121k
10 votes
Accepted

Where are cameras mounted on the 'Starman' payload of today's F-H launch?

There seem to be 3 on-car cameras, 2 of these are very clear from the "Starman in Red Roadster" post on Elon Musk's Instagram I've tried to highlight 3 of the Cameras, two of which (Hood and side ...
Edlothiad's user avatar
  • 2,137
10 votes
Accepted

Inclination vs payload capacity of a rocket

When you are launching a rocket into space with maximal inclination, is the payload capacity then the highest? Lowest, not highest. The maximum inclination (180°) results from launching due west from ...
David Hammen's user avatar
9 votes

How much bigger could Earth be, before rockets wouldn't work?

Not a planetological exposition in sight so, I'll add my two cents to this rather theoretical discussion. Amongst exoplanetologists, the consensus has emerged that 1.6 Earth radii and 5 Earth masses ...
pres1dentkang's user avatar
9 votes

How much mass could the Saturn V rockets have landed on the Moon if nothing was coming back?

And here is the answer from the Apollo era perspective: "Popular Science" text from 1966: "What We'll Do on the Moon", written by dr. Wernher von Braun himself! - Google Books link Unmanned cargo ...
szulat's user avatar
  • 773

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