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Share & discuss informative content on:

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  • Space Exploration
  • Planetary Science
  • Astrobiology


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    Eris mission

    How can we get a mission to dwarf planet eris im deferments to do this do we need to convince congress do we need to raise money because I will make sure we get a mission to eris I mean Pluto got one so why should Pluto get all the attention no one really cares about eris because we never sent a probe so how can we do this im looking for sudjestions I know it will take 24 years but I will wait who actually wants to see an eris mission and why I’m also sick of Pluto being everyone’s favorite

    01:27 UTC


    How will Starship locate itself when landing on Mars without GNSS?

    Measurements of an IMU (Internal Measurement Unit) alone are likely to have large cumulative errors. Are there any other approaches or even concrete plans? (lidar, radar, ...)

    01:19 UTC


    Photo of the Earths atmosphere and the moon. Shot by the international space station.

    00:30 UTC


    The moon sailing through the night sky

    00:03 UTC


    almost full moon 07/02/23

    1 Comment
    00:03 UTC


    Interview with Saturn V Engineer

    Not sure if this has been shared (I couldn't find it from a search). This is a great video by Destin from his Smarter Every Day YouTube channel. It's about an hour long and he does an in depth walk through of the Saturn V rocket with one of the original Engineers Luke Talley. Absolutely fascinating and I learnt lots of new facts.


    Longer 2 hour uncut version https://youtu.be/cUkbdqw9pBk

    1 Comment
    21:52 UTC


    Ιmpressive lasso-shaped solar plasma eruption (farside solar activity) - 7.2.23

    21:43 UTC


    Rank your top 10 favorite Planet, Dwarf Planets and Natural Satellites?

    I do not know the single world for all these combines. I just mean 1 list and why if you can.

    Here is my list

    1. Saturn: Has beautiful rings and beautiful on the outside

    2. Jupiter: My favorite gas giant and has a cool storm and color and nice size.

    Note All gas giants are beautiful but rank low as being a gas planet not very explorable or of usw lol

    1. Ceres: The only dwarf planet besides pluto on the list mostly because of its 1 crater with a massive light I want to see.

    2. Pluto: Yes the next dwarf is up next with a beautiful ice world.

    3. Venus: although my dislike for planets that look the same all around venus brakes this with its beautiful golden color.

    4. Ganymede and Callisto: Both tied because I forgot about another moon and I think they are equal in beauty and interest

    5. Tritan: 100% the tourist attraction of the solar system not somewhere I would want to live ignoring the deadly parts but a nice vacation

    6. Earth: Earth is amazing and we have so much to explore and could be number one but thats kinda basic if you do that its cool tho.

    The top 2 are phenomenal and hard to choose.

    1. Titan: basically a yellow golden earth with so much to see and so much variety its great.

    2. Europa yes titan may be way more beautiful, way more to see, also needed for scientist. However, Europa I believe is the most important thing in our solar system we should study. I feel here lies many answers and stories.

    Top 3 dislike:

    1. All satallites that look like moon is as bland as it can get.

    2. Io looks like a barf bag,

    3. Mars all scientist may hate my answer but extremely overrated and I feel like its only cuz its the closest to us that we can study. I think it is extremely ugly and a huge downgrade. I know as someone wanting to get into astronomy I should be excited about life on mars etc. I am kinda however, I hope we keep going after because im more intrested in all the other planets.

    18:42 UTC


    Given how rampant harassment is on remote research stations on the Earth, how can we use that knowledge to prevent similar things from happening on the Moon or Mars?

    If you don't know what I'm talking about, do read this: https://arstechnica.com/science/2023/02/as-antarctic-fieldwork-ends-a-sexual-harassment-reckoning-looms/amp/

    Apparently sexual harassment and assault are extremely common in the Antarctic research stations and have been for a very long time.

    That has obvious implications for space exploration and colonization as I am sure no potential astronaut wants to become a character in real life Among Us.

    So what can we do, now, to help make sure that never happens on a Moon or a Mars base to begin with? The ISS doesn't really have these problems so we know it's possible, and the fact that it's in LEO meaning a skeevy astronaut could still be arrested and held accountable is probably a large factor in that.

    But what about outside of Earth's gravity well? There's light lag between us and the Moon and especially Mars where the lag is upwards of 20 minutes one-way so what do we do if some clown of an astronaut decides to become a real-life Impostor? What do we do then?

    Would Earth law even apply on the Moon or Mars?

    17:45 UTC


    Verifying the Mars Ingenuity Helicopter's Feasibility via Calculation

    Having recently run the numbers for Starship over in /r/spacex, figure I'd do something similar on another craft.

    I've heard some doubt the existence of a helicopter on Mars (and recall reading such even in this subreddit), saying the atmosphere there is too thin to support aerodynamic flight. So, based on the data available for the vehicle and Mars, ran the numbers as best I could.

    In summary, Ingenuity has more than enough thrust to support (heh) hovering in the Martian atmosphere.

    Messy mathematical machinations follow.

    For a vehicle hovering on a propeller, an equation for static thrust is needed:

      T = ^(3)√(P^(2)✕ηₚ^(2)✕ηₑ^(2)✕π✕(d^(2)/2)✕ρ)


    • T is thrust (N)
    • P is power to motor (W)
    • ηₚ is propeller efficiency (0 thru 1)
    • ηₑ is motor efficiency (0 thru 1)
    • d is propeller diameter (m)
    • ρ is air density (kgm^(-3))

    Typical propeller and motor efficiencies:

    Numbers specific to Ingenuity on Mars:

    Thrust for a single propeller:

      T = ^(3)√(30625✕0.61✕0.64✕3.14✕0.72✕0.02)

       ≃ 8.1 N

       ≃ 0.83 kgF →

    One propeller generates more thrust than the helicopter weighs on Mars. So with two it has more than enough to hover and fly.

    14:47 UTC


    Favorite Space Movie?

    Interstellar is my top!

    16:12 UTC


    How does water factor into rocket launches?

    I was just watching a video (namely: https://youtu.be/Ax6yV8ZC_bc?t=117) and the presenter mentioned that SpaceX has three basic options to keep from having to rip up all the concrete after each booster static fire: Come up with better concrete, dig a big trench, or to use a water deluge system. But then he goes on to say that "dig a big trench" isn't viable because it would be below the water table and thus flood.

    ... But who cares if it floods given that "water deluge" is one of the other options you're considering?

    05:41 UTC


    Books like Rendezvous with Rama

    I've been on a space sci-fi binge lately and I especially enjoyed RWR. I love first contact stories. You guys have any suggestions?

    03:21 UTC


    cargo arrival and retrieval to go on the ISS

    01:05 UTC


    Dr. Robert Zubrin - Mars Direct: Humans to the Red Planet within a Decade

    23:20 UTC

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