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Why will the Raptor not face the same turnaround issues as Space Shuttle engines?

The RS-25's notoriously slow, expensive turnaround was blamed on its complexity. The Raptor appears about as complex. Both use regenerative cooling. Both use preburners to drive turbopumps. While the ...
Abdullah's user avatar
  • 2,553
5 votes
0 answers
216 views

Which (vintage?) CAD software is this in the Scott Manley video regarding The Titan Rocket

I was recently surprised by seeing a CAD software in the Scott Manley video that seems to be running on old computers in a command line like interface. Which software is this? and is it still used by ...
zephyr0110's user avatar
  • 2,901
0 votes
1 answer
93 views

How does SpaceX Raptor deliver a more benign turbine environment?

Raptor has been claimed to be able to deliver "long life ... and more benign turbine environments". https://en.wikipedia.org/wiki/SpaceX_Raptor The Raptor has hot oxygen flowing out of the ...
Abdullah's user avatar
  • 2,553
1 vote
0 answers
38 views

Using NASA Horizons with Celestrak Socrates's TLE CDMs?

Has anyone succeeded with getting a list of Collision Data Messages (CDMs) from nice sites like Celestrak in order to feed them into NASA Horizon's ephemeris computation service. These would include ...
Barry vT's user avatar
  • 321
1 vote
1 answer
123 views

Is it possible to generate a signal strong enough that it could be received on Alpha Centauri with today's technology?

Let's say we magically found out that there is an inhabited planet in the Alpha Centauri system and that the inhabitants there have the same level of technology that we do. Similarly, they know of our ...
Vilx-'s user avatar
  • 113
0 votes
1 answer
107 views

Turbo code used in New Horizons - encoding coefficient?

I know that New Horizons uses turbo code with r=1/6 for space communication1, however I don’t know which is the encoding coefficient, because I din’t think it could be 6, it seems it high. Could you ...
Spaceman's user avatar
-1 votes
2 answers
77 views

Higher density medium tube from sea level to space for travel

Is it theoretically possible to build a strong sealed tube from Earth's sea level all the way to Space, fill it with a medium (such as water) that has a higher density than humans. And then humans ...
Saurabh Goyal's user avatar
3 votes
2 answers
222 views

SpaceX Falcon Reusable First Stage Innovations

What are the top five innovations that SpaceX was able to accomplish that allows the first stage to land vertically and be reused? I am sure the Apollo program would have liked to reuse their first ...
still_learning's user avatar
4 votes
1 answer
135 views

What if Soyuz re-entered with orbital module attached?

Soyuz 5 and Soyuz TMA-11 survived reentry with an attached Service Module, which simply burned off. There have been no accidents where the Orbital Module has remained attached. What would be the ...
Abdullah's user avatar
  • 2,553
6 votes
2 answers
211 views

Is the crust of the Moon different on the near side and the far side?

If you assume that the origin of the Moon is due to an object hitting the Earth. The difference between far side and the near side of the Moon can be explained, if the 'chip' knocked off the Earth to ...
SR Clark's user avatar
11 votes
2 answers
1k views

Would we be able to tell if another civilisation built a Dyson sphere (or similar) around a distant star if we were looking for it?

A list of my thoughts/assumptions we have a good understanding of how stars live and die, so a "healthy" star (I assume you would only build a Dyson sphere around a star that's going to ...
Sam Dean's user avatar
  • 213
6 votes
1 answer
169 views

Sentinel-2C and frequency of acquisition

Sentinel-2C, the third Sentinel-2 satellite of the Copernicus program, is planned to be launched in 2024. Currently, the Copernicus SENTINEL-2 mission "comprises a constellation of two polar-...
AlixL's user avatar
  • 163
4 votes
3 answers
1k views

Could Falcon 9 push the second stage a little longer after MECO and before separation?

When watching Starlink launches I noticed the MECO/stage separation usually occurs at about 2m30s with the speed of about 8000 km/h and altitude about 65 km. After the separation the first stage with ...
Endrju's user avatar
  • 159
4 votes
0 answers
122 views

How was the external tank emptied in a TAL shuttle abort?

One of the numerous reasons RTLS was the least preferred choice is For a safe separation, the ET must contain a maximum of 2% propellant remaining at Main Engine Cutoff (MECO). How would TAL do away ...
Vorac's user avatar
  • 365
3 votes
0 answers
55 views

What was the longest Rocketdyne F-1 full power test?

This number is relevant to the issue of F-1 reusability, as it determines how many flights are required before serious work needs to be done. That is because LOX/Kerosene engines have coking problems ...
Abdullah's user avatar
  • 2,553
1 vote
0 answers
58 views

How much did it cost to turnaround Rocketdyne F-1 test articles?

Despite being intended for an expendable vehicle, the F-1 was tested and rated for the equivalent of more than ten reflights. How much did it cost to turnaround the test articles between the firings?
Abdullah's user avatar
  • 2,553
5 votes
0 answers
150 views

Glove in Phoenix Backshell?

I stumbled across this image which shows the Phoenix Lander being integrated into its backshell: This is the only image "source" I was able to find: https://picryl.com/media/phoenix-mars-...
RAD6000's user avatar
  • 1,128
3 votes
0 answers
101 views

How do ablatively cooled rocket engines compare to regeneratively cooled ones, in terms of mass?

Assuming equivalent thrust and single continuous burn duration, is there a figure that roughly tells the difference in mass between these two engines cooling methods? This question focuses on first ...
jkztd's user avatar
  • 3,966
14 votes
3 answers
3k views

Could the Rocketdyne F-1 have been reused?

Assuming the engine is recovered on a platform at sea similar to SpaceX, could it be refurbished and reflown at a low cost? Would the coking, corrosion, and other problems be any worse than that in ...
Abdullah's user avatar
  • 2,553
10 votes
2 answers
1k views

What's the motion of two connected satellites orbiting the Earth after their separation?

Let's consider the following problem (it's a job interview question): two satellites are orbiting the Earth in a circular orbit; they are rigidly linked by a tether which is always pointing in the ...
g_don's user avatar
  • 433
-3 votes
1 answer
114 views

At what point does an object lose 50% of escape velocity?

I find the kalman line an unsatisfactory definition of space. Instead, I will use 50% of escape velocity. At what distance does this happen? If escape velocity is 11 km s and gravity is 9.81, I am ...
D J Sims's user avatar
3 votes
0 answers
108 views

I am trying to create an inter-satellite network and run an inter-satellite routing protocols

I am trying to create a simulation of a network of cube sats connected to Earth station to provide me with internet. I want to run on these satellite a routing protocols can this be done using STK ...
tasnim's user avatar
  • 31
3 votes
1 answer
275 views

Geofence - satellite contact time

I need to find the access/contact times for a satellite passing through a random geofence (polygon). Is there a python library or any code to integrate the geofence to the orbit of the satellite to ...
v_space's user avatar
  • 41
13 votes
1 answer
2k views

How are those stunning space mission animations and images made?

I would like to understand which software/professionals are needed to produce the animations and images used to show how a space mission will be. For example: 1 - Curiosity video: ...
Ganimedes's user avatar
  • 163
2 votes
1 answer
34 views

Reducing degree of ICGEM's Gravity Field Models for orbit propagation

I would like to use one of the static gravity field models published at ICGEM for satellite orbit propagation. For example, EGM2008. Its degree is 2190. I would like to use only 360 (may be even less) ...
truf's user avatar
  • 123
3 votes
2 answers
119 views

Which notes and/or books on mathematics, physics, 3D geometry preparatory to the study of orbital dynamics?

I have a master's degree in aerospace engineering and I'm preparing for job interviews for orbital mechanics/space flight dynamics engineer positions and I need material about maths, physics, 3D ...
g_don's user avatar
  • 433
3 votes
2 answers
308 views

What are these composite overwrapped pressure vessels on Super Heavy?

https://en.wikipedia.org/wiki/SpaceX_Super_Heavy The oxygen tank has four chines attached. These protect the various COPVs on board, as well as providing lift during flight. First I've heard of ...
Abdullah's user avatar
  • 2,553
2 votes
1 answer
122 views

How much does it cost to build terrestrial ground station capable of controlling satellites orbiting the moon?

I'm noobie in space exploration and I want to carry out market research to find out how much it costs to build a terrestrial groundstation to control satellite missions that are in lunar orbit. Two ...
Ganimedes's user avatar
  • 163
5 votes
2 answers
235 views

Can electrodynamic tether propulsion use the solar magnetic field?

Electrodynamic tethers have been proposed for satellite propulsion in the magnetic fields of Earth and the Gas Giant planets. Is it realistic to consider using the Sun's magnetic field for ...
Woody's user avatar
  • 15.3k
8 votes
3 answers
3k views

Why can't buoyancy of air be used to support a mega structure as an alternative to a space elevator?

The reason for asking this question stems from recent articles about large loss of strength of carbon nano tubes with even single atom movement, tested samples showing high vulnerability to space ...
stringue's user avatar
2 votes
0 answers
143 views

Is the rocket exhaust plume at liftoff of a liquid fuled rocket cold? Can it condense? [duplicate]

I try to understand what the exhaust cloud on the ground from the start of Starship consists of. Of course it was unusually mineral-rich, but I try to understand whether we saw much else, apart from ...
Volker Siegel's user avatar
1 vote
1 answer
105 views

How do you calculate the characteristics of an orbit of an object launched from a mass driver?

What formula can I use to calculate the apoapsis of the orbit of an object launched from a mass driver on the moon at a given speed and angle to the surface (angle from horizontal)? The device will ...
kim holder's user avatar
  • 21.2k
5 votes
1 answer
177 views

ARCA Aerospace has announced the EcoRocket Heavy, a wider-than-tall rocket. Has there ever been any other seriously proposed rockets wider than tall?

Is this the first seriously proposed/planned launch vehicle that is wider than it is tall? https://www.arcaspace.com/ecorocket
qazwsx's user avatar
  • 932
4 votes
2 answers
206 views

How do Centrifugal Turbopumps work? How do you make one?

I recently visited Wikipedia to look at centrifugal pumps and axial pumps. Centrifugal pumps are very interesting, and I was wondering how they work in more depth. I really don't understand how they ...
Anish's user avatar
  • 41
5 votes
0 answers
78 views

Does space have the same salvage laws as maritime law? [duplicate]

With the international space station being decommissioned within the decade and other abandoned satellites what are the rules on independently saving these objects?
Joe's user avatar
  • 357
7 votes
1 answer
1k views

How do we define the aphelion of Earth?

After seeing this question, I was curious on how we define the aphelion of Earth. On a quick search it said that the aphelion is the point when Earth is the furthest way from the sun. However, all the ...
The Rocket fan's user avatar
3 votes
1 answer
74 views

ROFI Temperature

Since hydrogen-fueled rockets usually require Radial Outward Firing Igniters (ROFI), what is the temperature of the sparks from this system? When seen at RS-25/RS-68 ignition, they don't melt but ...
TRK's user avatar
  • 129
30 votes
1 answer
6k views

Is there someone continually monitoring the Voyager spacecraft?

I just finished watching The Farthest, a great documentary about the Voyager spacecraft, launched in 1977 and still operational today. It got me wondering about those people shown in the documentary ...
Stu Smith's user avatar
  • 453
1 vote
0 answers
78 views

Moving target during rendezvous

I am currently studying rendezvous and docking. I noticed the elliptic Hill equations only consider the acceleration of the target satellite due to its elliptic orbit (and fictitious forces in LVLH ...
Sato Yusei's user avatar
5 votes
1 answer
266 views

Was the exhaust cloud at the Starship launch mostly pulverized launchpad?

The launch of Spacex Starship on April 20 2023 looked pretty normal on first sight, apart from some engines not running, and some concrete flying around. The huge exhaust cloud looked normal, because ...
Volker Siegel's user avatar
4 votes
0 answers
126 views

Why did LEM ascent stage swing during flight?

While watching Apollo 17 ascent footage, I've noticed that the camera is swinging quite a bit. It is definitely fixed to a window, so it means that the whole ascent stage is swinging back and forth ...
radical_gale's user avatar
15 votes
2 answers
2k views

How do the interferometers on the drag-free satellite LISA receive power without altering their geodesic trajectory?

LISA is a proposed space probe designed to measure gravitational waves. It aims to measure gravitational waves directly by using laser interferometry. It uses a drag-free satellite design to protect ...
Woody's user avatar
  • 15.3k
8 votes
1 answer
445 views

How are engines numbered on Starship and Super Heavy?

I was watching this video summarizing Elon Musk's recent remarks on the orbital test flight, and they mention specific engines. But unless a named engine shuts down and is shown on the small display ...
Abdullah's user avatar
  • 2,553
5 votes
1 answer
255 views

For Starship, using B9 and later, how will separation work if the Hydraulic Power Units are no longer needed for the TVC System?

On the SuperHeavy booster, the 33 engines break down into two sets, 20 outer engines that cannot relight (That equipment is actually on the pad itself) and cannot gimble. The inner 13 consist of a ...
geoffc's user avatar
  • 78.9k
2 votes
0 answers
41 views

Add small extra gps antenna on tracker installed inside aluminum tube [closed]

I would like to install a GPS tracker inside a scooter. Will the GPS signal will be lost if I install the tracker inside the vehicle? Can I add a small extra antenna to fix outside the scooter?
Marc D's user avatar
  • 21
2 votes
1 answer
225 views

Will this homopolar motor self rotate in a vacuum?

Is it convenient to ask about the motor from the link: Roller Homopolar Motor When it is on the table, the motor rotates freely, together with the attached conductor. Will the upper motor in the ...
user51174's user avatar
8 votes
2 answers
5k views

If we had a video livestream of a clock being sent to Mars, what would we see?

If, you hypothetically started 2 clocks at exactly the same time, and placed one on Earth, and one on a rocket to Mars, and setup a video feed of both clocks, how would they compare as the 2nd clock ...
Elliot Lewis's user avatar
5 votes
1 answer
75 views

Can waterworld exoplanets have an ocean that's fresh or brackish by terrestrial standards?

The basic system is a terrestrial-type exoplanet in the liquid water zone around a star. The planet has a worldwide, liquid ocean with at most small islands above the surfaceMy question is what the ...
Heteromeles's user avatar
6 votes
2 answers
500 views

Does methalox fuel have a coking problem at all?

Methane was chosen for SpaceX Raptor because it has less coking problem that kerosene. But does it completely eliminate it? If not, how much less severe is it? I googled 'thermal decomposition of ...
Abdullah's user avatar
  • 2,553
7 votes
1 answer
1k views

Has depleted uranium been considered for radiation shielding in crewed spacecraft beyond LEO?

Does Depleted Uranium (DU) have a role in spacecraft shielding? Crewed spacecraft require shielding to protect crew from hazards of space, particularly: Micrometors. The chief defense is a Whipple ...
Woody's user avatar
  • 15.3k

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