All Questions

Filter by
Sorted by
Tagged with
2
votes
0answers
55 views

Was Arthur J. Schwaniger one of very few US born NASA scientists using metric units?

Free-return trajectories were studied by Arthur Schwaniger of NASA in 1963 with reference to the Earth–Moon system. Those trajectories were used for the first Apollo missions. Mr. Schwaniger, who ...
9
votes
3answers
2k views

What is this spacecraft tethered to another spacecraft in LEO (vintage)

In the really nice video Brian Eno on Apollo at 03:40 there is (possibly Apollo-era but not necessarily Apollo) footage of a spacecraft tethered to another ...
3
votes
1answer
206 views

What does this humanoid silhouette on SpaceX's Starhopper represent?

The images below are from a NASA Spaceflight forum post and can be seen in @bolsachicagal's twitter and also in this NASASpaceFlight tweet. Question: What does this silhouette of a bipedal individual ...
5
votes
1answer
424 views

How “hard” did Apollo 12 turn left just before it landed?

This answer to How much were the LMs maneuvered to their landing points? includes Figure 34 from Floyd Bennett's 1972 Apollo Experience Report - Mission Planning for Lunar Descent and Ascent; NASA TN ...
1
vote
0answers
34 views

Mass/weight information about stage separation mechanism

How can I get mass/weight information about rocket stage separation mechanisms that are used in multi-stage rockets? I plan to create an excel table to compare stage separation mechanisms by weight ...
5
votes
1answer
119 views

Why did a phase mismatch between the Apollo 11 LM's RR and AGC generate a large numbers of interrupts?

A critical aspect of the cause of the famous 1202 and 1201 alarms reported by the Apollo Guidance Computer (AGC) during the decent of the Apollo 11 LM is that the rendezvous radar (RR) was using a "...
7
votes
3answers
519 views

How much were the LMs maneuvered to their landing points?

The story of the Apollo 11 landing includes Armstrong having to fly the LM beyond a boulder field at the automatically targeted site. Was this essentially continuing along the same track the LM had ...
4
votes
1answer
255 views

Why did Germany launch its spy satellites from Russia?

I just saw this article on a family of German recon sats https://en.wikipedia.org/wiki/SAR-Lupe They were all launched from Russia! Why? Why not an Ariane launch from French Guiana? I can ...
0
votes
2answers
114 views

Why do we not have ten small rovers on the Moon already? [closed]

We already did the develop and testing of Opportunity and Curiosity for 15 years. Why not crank out ten more, and put them on a Falcon heavy for the Moon's south pole?
7
votes
1answer
91 views

ESA's contribution to ISS: what has succeeded the ATV?

ESA's ATV cargo spacecraft was built and flown as part of ESA's contribution to the ISS operating cost. This program has ended. What has replaced it? Has ESA's financial contribution increased, or ...
1
vote
1answer
86 views

What exactly is a “Next Generation Lunar Reflector”? Difference in design and performance?

Space.com's 50 Years After Apollo, India Is Carrying a NASA Laser Reflector to the Moon (And It's Only the Start) is a little confusing because it talks about three retroreflectors: - Apollo era ...
3
votes
1answer
51 views

How can I calculate if a satellite is currently in sunlight or eclipse using pyEphem or Skyfield (preferred)?

I'd like to add this to some existing python scripts to model cubesat battery life and payload temperature but the math escapes me.
3
votes
1answer
115 views

How long will traces of the moon landings survive?

Inspired by this question: How long will traces of the moon landings (e.g. footsteps, the hardware) or other human activity on the moon approximately survive to be recognized as unambiguous evidence ...
1
vote
1answer
71 views

Impact of having two antennas on link budget calculations

I'm working on link budget of a cubesat mission that needs to have two dipole antennas that are perpendicular to each other. I want to know if having two antennas affect the link budget? losses, and ...
2
votes
1answer
128 views

What causes this diamond to appear from a single Raptor engine firing?

As seen on this video posted by Elon Musk https://twitter.com/elonmusk/status/1154629726914220032?s=19
0
votes
1answer
91 views

Could Spacex build a starhopper (starship prototype) at Vandenburg, CA launch site?

I know Spacex is building a starhopper (starship prototype) in Texas and Florida. Could they also build a starhopper prototype at the Vandenburg, CA launch complex? I know Vandenburg is better for ...
6
votes
1answer
142 views

Does central Merlin have a different specific impulse?

On a Falcon 9 booster, does the central engine experience unique variations of its ISP due to its plume bordering the eight other plumes? If there is any influence, how does the ambient relative ...
1
vote
0answers
25 views

Orbital period from TLE data [duplicate]

Is there a way to calculate the orbital period from the Two Line Element (TLE) data?
11
votes
2answers
2k views

How were the LM astronauts supported during the moon landing and ascent? What were the max G's on them during these phases?

I understand that the LM astronauts descent trajectory had them flying feet first in a standing position during the descent to the lunar surface and again on ascent. But it seems there must have been ...
39
votes
6answers
7k views

Why did Saturn V not head straight to the moon?

This may seem a naive question, but as I understand it one of the reasons for the enormous energy expended by rockets is the extremely high speed (around 28,000kph) you need to reach to achieve a ...
1
vote
2answers
74 views

What is the process to verify the orbit of a satellite in a list of artificial earth satellites?

From the answers to What is the name of the 'register' that keeps track of all the satellites? we can see that there are more than three 'registers' of artificial satellites - starting with: The ...
5
votes
1answer
552 views

Does static fire reduce reliability?

I do understand that static fire helps discovering malfunctions, as explained in this answer. A launch exerts an important stress on rockets' engines (high temperature and pressure, vibrations,...) ...
7
votes
1answer
373 views

Why did they bother closing the hatch on the LM while doing EVA?

In the transcript of the Apollo 11 EVA on the Moon, Buzz Aldrin mentions closing the LM's hatch and being careful not to lock the two astronauts out. ...
1
vote
1answer
80 views

Solar system sized telescope and resolving details of the M87 black hole

In this video Katie Bouman mentions that an earth sized telescope needs to be used for getting images like the M87 Black Hole: Stellar distances are estimated using ...
2
votes
1answer
96 views

What is the meaning of the ROSCOSMOS logo?

ROSCOSMOS is the Russian state corporation for space exploration. Its logo is below. What is the official meaning or significance of the parts of the logo? ROSCOSMOS' main launch site (Baikonur ...
7
votes
1answer
1k views

What are/were the Customs requirements for astronauts?

When the Apollo 11 astronauts returned to US territory they famously went through US Customs where they listed "moon" as part of their flight routing: Was that a one-off? What are procedures today? ...
2
votes
1answer
67 views

Feasibilities and challenges of these Orion + commercial lunar lander scenarios? [closed]

Suppose that US politicians want to fund a moon mission without SLS, using only hardware that is working now in 2019, using Orion together with some future moon lander supplied by the private sector. ...
5
votes
1answer
120 views

Has an IV even been performed or attempted in space?

As many of you likely know, IV's are an important part of modern medicine. As more and more people go into space for longer periods, I would imagine it may become necessary for an IV to be ...
2
votes
0answers
191 views

How will SpaceX's Starship accommodate its 100 passengers from the effects of micro-gravity?

According to this Wikipedia article, Starship will take on average 115 days (3.8 months) to get to Mars and 150 days maximum (4.9 months). with an average trip time to Mars of approximately 115 ...
6
votes
1answer
147 views

Which unit system was used by german rocket scientists at NASA for calculations?

There were numerous german rocket scientists at NASA, see wikipedia 1, 2. They were used to the metric system which they used when working for the V-2 at Penemünde. But what unit system did they use ...
3
votes
1answer
142 views

Is vertical assembly worth the cost (Ariane 6)

Very recently, ESA released a new video showing the proposed Ariane 6 rocket being assembled. This mostly takes place in a large 'moveable gantry' building where the payload is placed on top of the ...
4
votes
2answers
120 views

What is the name of the 'register' that keeps track of all the satellites?

I imagine there must be a list of all the satellites ever launched and their coordinates. I can't find it on Google. My question is: What is the name of the 'register' that keeps track of all the ...
2
votes
0answers
102 views

What do these three historical IBM staff at NASA insignias designate?

The question Where are these historical IBM + Apollo related locations within NASA? What do these computers do? shows four images. Three of them show different IBM insignias on shirts of IBM staff. ...
4
votes
1answer
126 views

Where are these historical IBM + Apollo related locations within NASA? What do these computers do?

In the Fortune Magazine video IBM's Moonshot: Past and Future with the notes BM’s John Kelly reflects on Apollo 11’s historic mission and looks forward to what future technology will accomplish. ...
5
votes
1answer
139 views

What was the purpose of a Boyd Bolt?

The Apollo Lunar Surface Experiments Package (ALSEP) used a kind of spring-loaded bolt called a "Boyd Bolt", named after its inventor. There is a NASA page on it here. Can someone explain in plain ...
1
vote
2answers
94 views

Do satellites inject into a Hohmann transfer orbit in Low Earth Orbit or in Solar orbit?

Lets say we have a satellite wanting to go to Mars. Do satellites such as MAVEN inject into a Hohmann transfer orbit while in Earth's orbit, or do they go out of Earth's Sphere of Influence into solar ...
2
votes
0answers
26 views

Soyuz reentry acceleration profile with timing

I am looking for reentry Soyuz acceleration profile with timing. I was able to find graphs for ascent, but failed to find anything related with descent. The only thing I've got is Andreas Mogensen ...
0
votes
1answer
180 views

Does Chandrayaan 2 use gravity assist?

All of the descriptions I've seen online describing Chandrayaan-2's path to the Moon either explicitly or implicitly describe it involving a "gravity assist": The spacecraft will make use of the ...
2
votes
1answer
25 views

Rotation matrix from J2000 to ITRF2008

I want to rotate a vector from the inertial J2000 frame into ITRF2008. I am using the NASA SPICE library, which provides a rotation matrix from J2000 to ITRF93 (they plan to upgrade the library to a ...
11
votes
2answers
1k views

Were the Apollo broadcasts recorded locally on the LM?

I've previously asked about how the recordings from the Apollo missions were originally recorded, and then transcribed; but I forgot about the video as well! It's well known that for some of the ...
1
vote
1answer
57 views

How do you calculate the ∆v required to increase apoapsis to a certain height?

To calculate the ∆v needed to increase our apoapsis from a low orbit of 100km to 400km, we find the velocity at 100km using the semi major axis (which is 250km, in this case), and then find the ...
2
votes
1answer
76 views

What are the historical fastest and longest time between take off and orbit insertion?

The question is restricted to payloads having described at least 2 orbits. When watching launches, it appears that between launch and orbit insertion, the typical time interval is few minutes (...
23
votes
1answer
2k views

Was US film used in Luna 3?

This site claims that the USSR's Luna 3 probe, the first to photograph the far side of the moon, used special radiation and temperature hardened film taken from downed US spy balloons. Is this true? ...
42
votes
3answers
14k views

Why did NASA use U.S customary units?

NASA was using U.S customary units (inches, feet, nautical miles, pounds, tons, US gallons etc.) during the Mercury and Apollo programmes, and beyond. There are significant disadvantages to using U.S ...
15
votes
4answers
8k views

Are rockets faster than airplanes?

Rockets are fast. Faster than anything else somebody could fly with - at least intuitively to me. But - airplanes are fast too. A rocket typically flies vertically, an airplane mostly horizontally. ...
2
votes
1answer
39 views

What are the differences between various solar weather terms?

In preparation for my own possible question on solar weather, I searched for past questions on the topic. The past questions suggest that I am not the only person who is confused about the ...
1
vote
0answers
38 views

How to plot conic from Lambert solver

I am trying to solve for an optimal multi-gravity assist trajectory from Earth to Saturn using Matlab. I have already solved for the departure and arrival velocities from and to each planet using a ...
2
votes
2answers
104 views

why dose reentry speed need to be so fast [duplicate]

I have been wondering this since I was a kid. watching films of capsules and shuttles heating up and all that tile trouble and work that went into all. I would always wonder why they dont slow down ...
18
votes
2answers
3k views

What gave NASA the confidence for a translunar injection in Apollo 8?

In Carrying the Fire, Michael Collins observes humorously that Apollo 8 was only the third time the Saturn V had flown. To a non-specialist, it does seem remarkable that NASA was confident to put ...
5
votes
2answers
136 views

What orbit would a space station need to stay in orbit for $N$ years?

(posted before on physics stackexchange but was told to come here) I'm reading this book which has a post-apocalyptic setting. At one point you look at the earth from the view of a 1000-year-old ...

15 30 50 per page