131
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 ...
- 167k
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 ...
- 79.4k
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 ...
- 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 ...
- 73.2k
36
votes
Accepted
What's the largest single object payload ever lifted into space?
Depending on your definitions, the contenders seem to be the US Space Shuttle, Buran, Apollo 17, or Skylab.
...
- 167k
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 ...
- 1,103
30
votes
How much bigger could Earth be, before rockets wouldn't work?
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 ...
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 ...
- 178k
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
- 1,788
23
votes
Accepted
How much mass could the Saturn V rockets have landed on the Moon if nothing was coming back?
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 ...
- 167k
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 ...
- 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 ...
- 126k
21
votes
Accepted
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. ...
- 121k
21
votes
Accepted
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 ...
- 79.4k
21
votes
Accepted
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 ...
- 9,377
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 ...
- 1,173
18
votes
Accepted
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 ...
- 3,256
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
...
- 5,271
17
votes
Accepted
How would a long pole be transported to space?
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 ...
- 4,218
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 ...
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 ...
- 167k
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 ...
- 121k
14
votes
What's the largest single object payload ever lifted into space?
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 ...
- 9,414
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 ...
- 687
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 ...
- 167k
11
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....
- 148k
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 ...
- 126k
11
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 ...
- 3,412
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 ...
- 121k
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 ...
- 126k
Only top scored, non community-wiki answers of a minimum length are eligible