Page 96 of 161 FirstFirst ... 4686888990919293949596979899100101102103104106146 ... LastLast
Results 2,376 to 2,400 of 4011
  1. #2376
    Thailand Expat
    Takeovers's Avatar
    Join Date
    Nov 2008
    Last Online
    Today @ 02:44 AM
    Location
    Berlin Germany
    Posts
    7,056
    I found some info on the orbits they are going to fly into. Now that's batshit crazy. No need to do something like this ever except for demonstrating they can. Changing altitude is not that hard. But changing inclination takes vast capabilities. That's the last item in eachline the deg value.

    300 km x 860 km x 28.5 deg
    720 km x 720 km x 24 deg
    6000 km x 12000 km x 43 deg
    After all these and deploying the sats they still do the deorbit burn.
    "don't attribute to malice what can be adequately explained by incompetence"

  2. #2377
    Thailand Expat
    Join Date
    Oct 2015
    Last Online
    16-07-2021 @ 10:31 PM
    Posts
    14,636
    awesome pics

  3. #2378
    Thailand Expat OhOh's Avatar
    Join Date
    Jul 2010
    Last Online
    Today @ 12:38 PM
    Location
    Where troubles melt like lemon drops
    Posts
    25,223
    Quote Originally Posted by Takeovers View Post
    That's the last item in eachline the deg value
    Presumably the degree are of latitude?

    Also further away, nearer and then back out, further away from earth.

    One would have thought they would start at 24, then 28.5 and finish at 43. What degree do they need to come back to, to land?

    That's a lot of engine firings, on to get out, a turn around, on to slow down to get back in ....
    A tray full of GOLD is not worth a moment in time.

  4. #2379
    Thailand Expat
    Takeovers's Avatar
    Join Date
    Nov 2008
    Last Online
    Today @ 02:44 AM
    Location
    Berlin Germany
    Posts
    7,056
    Quote Originally Posted by OhOh View Post
    Presumably the degree are of latitude?
    Yes.

    Quote Originally Posted by OhOh View Post
    Also further away, nearer and then back out, further away from earth.

    One would have thought they would start at 24, then 28.5 and finish at 43. What degree do they need to come back to, to land?
    I think it is overall the minimum of delta-v needed.

    720 km x 720 km x 24 deg
    They need to circularize to that orbit then to get out of it again. Doing it in another order would require 2 burns to reach that circular orbit.

    Quote Originally Posted by OhOh View Post
    That's a lot of engine firings, on to get out, a turn around, on to slow down to get back in ....
    Yes, a lot of engine firings. Unusual to have so many. But at least 2, sometimes 3 are not unusual. First injection into an elliptial orbit on launch, then circularize at apogee, then, if they still can, deorbit.

    Merlin engines are built for many relights. First stages for landing fire at launch. Then do a burn to return to the launch site, then a reentry burn to reduce speed at atmospheric reentry, then a landing burn, so 4 burns as well. The difference is these burns are not mission critical. They deliver the payload with the first burn, the others are "only" to recover the stage. In this mission each burn is mission critical.

    All done to demonstrate versatility and reliability of the system to the Airforce. I am sure there will be a collective sigh of relief when all is done. Also President of SpaceX Gwynne Shotwell will hug a few people in the control center, she does that after successful important missions.

    Edit: BTW the whole process will take 6 hours. That time is important. The Airforce wants some satellites directly delivered to GEO orbit at 36,000km altitude. Commercial sats are usually delivered to a transfer orbit with apogee at ~36,000km and circularize themselves from a low perigee. To circularize at that altitude the coast time is 6 hours. Relighting after that much time is a new capability SpaceX developed for this purpose. They already showed the capability with their first FH launch, the one that sent a Tesla roadster into deep space. But the Airforce wants to see that again with the present block 5 version of Falcon.
    Last edited by Takeovers; 21-06-2019 at 01:35 PM.

  5. #2380
    Thailand Expat
    Takeovers's Avatar
    Join Date
    Nov 2008
    Last Online
    Today @ 02:44 AM
    Location
    Berlin Germany
    Posts
    7,056
    Definitely older pic, the side boosters are clean. It does give the full impression how massive this thing is. Not the biggest booster ever but the biggest and most powerful presently flying.



    The side boosters are the same though. In this pic before flight. Another pic of the stack that will fly the Airforce mission. Same bosters but after the first flight. They no longer clean them between flights. They decided it is not necessary.

    Space News thread-190620-ksctour-181-jpg

    Stack on the pad after doing a static fire test. By now it is back in the hangar for attaching the payload. There is a payload fairing at the top but it is empty. The Airforce wanted it to measure noise levels during the static fire. It will be removed and the real payload attached.

    Edit: BTW someone at the NSF forum calculated that the total delta-v to change the orbits twice is almost enough to send the payload to Mars instead the two different orbits.
    Attached Thumbnails Attached Thumbnails Space News thread-190620-ksctour-181-jpg  
    Last edited by Takeovers; 22-06-2019 at 02:20 PM.

  6. #2381
    Thailand Expat OhOh's Avatar
    Join Date
    Jul 2010
    Last Online
    Today @ 12:38 PM
    Location
    Where troubles melt like lemon drops
    Posts
    25,223
    Quote Originally Posted by Takeovers View Post
    the total delta-v to change the orbits
    Thanks.

    For anybody else a little less knowledgable, like me

    "Delta-v (literally "change in velocity"), symbolised as ∆v and pronounced delta-vee, as used in spacecraft flight dynamics, is a measure of the impulse that is needed to perform a maneuver such as launch from, or landing on a planet or moon, or in-space orbital maneuver.

    It is a scalar that has the units of speed. As used in this context, it is not the same as the physical change in velocity of the vehicle.

    As a simple example, take a conventional rocket which achieves thrust by burning fuel. Delta-v is the change in velocity that can be achieved by burning that rocket's entire fuel load.


    Delta-v is produced by reaction engines, such as rocket engines, and is proportional to the thrust per unit mass and the burn time. It is used to determine the mass of propellant required for the given maneuver through the Tsiolkovsky rocket equation.


    For multiple maneuvers, delta-v sums linearly."

    For the mathematically competent look down the page for this heading:

    Orbital maneuvers

    https://en.wikipedia.org/wiki/Delta-v#Orbital_maneuvers

  7. #2382
    R.I.P. Luigi's Avatar
    Join Date
    Dec 2014
    Last Online
    @
    Location
    Abuja
    Posts
    26,213
    A recent discovery on Mars has been in the news lately.

    Surprising amounts of Methane are being recorded in the atmosphere.

    A gas usually produced by living creatures on Earth.

    Due to the atmospheric conditions, it must be relatively newly produced, which hints at living microbes currently, or recently living there.

    https://www.nytimes.com/2019/06/22/s...over-life.html

  8. #2383
    Thailand Expat OhOh's Avatar
    Join Date
    Jul 2010
    Last Online
    Today @ 12:38 PM
    Location
    Where troubles melt like lemon drops
    Posts
    25,223
    I dont suppose the Martian Rover is diesel powered?

  9. #2384
    Thailand Expat
    Takeovers's Avatar
    Join Date
    Nov 2008
    Last Online
    Today @ 02:44 AM
    Location
    Berlin Germany
    Posts
    7,056
    Quote Originally Posted by Luigi View Post
    Surprising amounts of Methane are being recorded in the atmosphere.

    A gas usually produced by living creatures on Earth.
    There are non biological sources discussed. The surprising amount is still in the range of 2ppb, a minute amount. Parts per billion not per million.

  10. #2385
    Thailand Expat
    Takeovers's Avatar
    Join Date
    Nov 2008
    Last Online
    Today @ 02:44 AM
    Location
    Berlin Germany
    Posts
    7,056
    STP-2 lifted off successfuly today. The rocket performed flawless and delivered all 24 sats to their intended orbits.

    nightlaunch always spectacular
    Space News thread-fh-launch-jpg
    Plume interaction. Down somewhat blue the center core continuing its flight. Up the two separated side boosters on their way back to the launch site for successful landing. No good photos at night.
    Space News thread-fh-interaction-jpg

    Long exposure from launch to side booster return.
    Space News thread-fh-boostback-jpg

    They caught one half of the fairing for the first time. Maybe renaming the ship from Mr. Steven to GO Ms. Tree did help. The plan was to catch one half this time. The second half will be fished out of the water again. For the future they plan to catch both halfes. Not sure how they will do that with one ship but that's the plan.
    Space News thread-fh-fairing-jpg


    Landing the center core failed again. This was the longest flight and highest speed of a center core yet. Elon Musk had given a 50% chance for success. They will learn and succeed. Other launch companies might succeed at first try. But they would spend billions and years of development while SpaceX already flies and makes money.
    Space News thread-fh-center-jpg
    Attached Thumbnails Attached Thumbnails Space News thread-fh-launch-jpg   Space News thread-fh-interaction-jpg   Space News thread-fh-boostback-jpg   Space News thread-fh-fairing-jpg   Space News thread-fh-center-jpg  

    Last edited by Takeovers; 25-06-2019 at 08:18 PM.

  11. #2386
    Thailand Expat
    Takeovers's Avatar
    Join Date
    Nov 2008
    Last Online
    Today @ 02:44 AM
    Location
    Berlin Germany
    Posts
    7,056
    A gif of the failed landing
    Usually the stream cuts out on landing. Many thought this is intentional to hide possible failures. Now this landing failed and the stream did not cut out. The reason for cutting out is that shaking and ionization disrupts the connection. Not intentional cutting out. As far as we know the stage hit the water far enough from the Drone Ship that it did not cause damage.


    Space News thread-acceptableplayfuldinosaur-small-gif
    Attached Thumbnails Attached Thumbnails Space News thread-acceptableplayfuldinosaur-small-gif  

  12. #2387
    Thailand Expat
    Join Date
    Oct 2015
    Last Online
    16-07-2021 @ 10:31 PM
    Posts
    14,636
    so what are you saying? did it fail to protect the Drone?

  13. #2388
    Thailand Expat
    Takeovers's Avatar
    Join Date
    Nov 2008
    Last Online
    Today @ 02:44 AM
    Location
    Berlin Germany
    Posts
    7,056
    Quote Originally Posted by Dragonfly View Post
    so what are you saying? did it fail to protect the Drone?

    Failed landing so far were so close to the Drone Ship that the Drone Ship was damaged. Part of the reason was that SpaceX wanted to demonstrate that even worst case they can hit the exact spot they were aiming for. It helped them to get permission to land landing early at the price of a lot of repairs. Actually a lot of people were quite surprised how early the Airforce permitted SpaceX to do land landing. This time, intentionally or not, the rocket missed the ship and did not cause damage.

  14. #2389
    Thailand Expat OhOh's Avatar
    Join Date
    Jul 2010
    Last Online
    Today @ 12:38 PM
    Location
    Where troubles melt like lemon drops
    Posts
    25,223
    An article on the recent return trip to earth by three ISS crew.

    Soyuz brings Space Station Expedition 59 back to Earth

    https://www.rt.com/news/462607-soyuz-space-station-expedition-59/

    Nothing exceptional but two points/questions.

    "Russian cosmonaut Oleg Kononenko, Canadian Space Agency astronaut David Saint-Jacques and NASA astronaut Anne McClain landed on the steppes of Kazakhstan on Friday morning, roughly three and a half hours after departing the ISS onboard the Soyuz MS-11 spacecraft."

    What are they doing for 3 and a half hours during the return?

    A video;



    The images from inside the ISS, the immediate vicinity of the ISS and the astronauts leaving the landed capsule/being weighed and measures etc. are pretty decent quality.

    The middle portion of the capsules parachute decent and especially the landing are abysmal.

    Is the middle portion recorded by much inferior equipment or degraded to hide something?

    No sight/news of the 3rd astronaut, the Canadian.
    Last edited by OhOh; 26-06-2019 at 04:31 PM.

  15. #2390
    Thailand Expat
    Takeovers's Avatar
    Join Date
    Nov 2008
    Last Online
    Today @ 02:44 AM
    Location
    Berlin Germany
    Posts
    7,056
    Quote Originally Posted by OhOh View Post
    What are they doing fr 3 and a half hours during the return?
    Sitting in there very tight. Soyuz is not comfortable during landing. Much better during ascent to the ISS, even if they do a long approach because they have the orbital module for extra space.

  16. #2391
    Thailand Expat
    Takeovers's Avatar
    Join Date
    Nov 2008
    Last Online
    Today @ 02:44 AM
    Location
    Berlin Germany
    Posts
    7,056
    I love those shots of the engine exhaust stream with extremely short exposure. Unlike picture we were used to see it is not just a brilliant pillar of flame but it shows there is a lot of short lived structure in there.

    Space News thread-h3wnogddqk631-jpg

    Elon Musk has given the reason for the center core landing failure. It was the hottest reentry by far and the TVC, thrust vector control, the gimbaling hardware used to steer failed.

    We will see if they do upgrades or not do such extreme landings again.
    Attached Thumbnails Attached Thumbnails Space News thread-h3wnogddqk631-jpg  

  17. #2392
    Thailand Expat OhOh's Avatar
    Join Date
    Jul 2010
    Last Online
    Today @ 12:38 PM
    Location
    Where troubles melt like lemon drops
    Posts
    25,223
    Quote Originally Posted by Takeovers View Post
    I love those shots of the engine exhaust stream
    Your just a pyrotechnic chemical addict, admit it.

    I bet you run 5th of November displays. Are you a finger on the firing button or a relighting the fuse guy?

    Quote Originally Posted by Takeovers View Post
    It was the hottest reentry by far and the TVC, thrust vector control, the gimbaling hardware used to steer failed.
    That is a launch photo, yes?. As there appears to be three groups of engines and don't the side boosters land independently?

    Those engines and surrounding equipment must get a lot hotter when coming down, into the hot exhaust zone. Compared to taking off, when most of the heat is cooled by the new fuel and is quickly left behind.

    Saying that in some of the heavy rocket launch videos they do seem to take an age before starting to move at all and then moving upwards at any speed.

    Are there any videos/pictures of that type/quality showing the, landing on the barge/ground pad, phase?

    I'm pretty sure you have an 8 TB full, attached to your computers and your house wall sized screen, as I type.
    Last edited by OhOh; 26-06-2019 at 04:59 PM.

  18. #2393
    Thailand Expat
    Takeovers's Avatar
    Join Date
    Nov 2008
    Last Online
    Today @ 02:44 AM
    Location
    Berlin Germany
    Posts
    7,056
    Quote Originally Posted by OhOh View Post
    That is a launch photo, yes?. As there appears to be three groups of engines and don't the side boosters land independently?

    Those engines and surrounding equipment must get a lot hotter when coming down, into the hot exhaust zone. Compared to taking off, when most of the heat is cooled by the new fuel and is quickly left behind.

    Saying that in some of the heavy rocket launch videos they do seem to take an age before starting to move at all and then moving upwards at any speed.

    Are there any videos/pictures of that type/quality showing the, landing on the barge/ground pad, phase?

    I'm pretty sure you have an 8 TB full, attached to your computers and your house wall sized screen, as I type.
    Yes, the side boosters return to the launch site and land there. The two boosters of this flight have flown on a Falcon Heavy before. They landed successfully this time as well and will fly again. The engine exhaust is hot but not this hot. The real heating comes when they hit the atmosphere at ~2km/s (don't nail me on the number, it is from memory). But the center core this time was faster than that, too fast and got damaged.

    The landing was not very well visible at night. Here the video from the launch in april. It is the same boosters as this flight. It shows launch, spectacular landing of both side boosters at the cape and landing of the central core out at sea.



    That launch they landed the central core as well, perfectly. Except that the sea was quite rough and they could not enter the Drone Ship to secure it. So they lost it to the waves later. This time they had the octograbber modified for the central core but the landing was a failure.

    Space News thread-octograbber-jpg

    Space News thread-ocotograbber-plus-booster-jpg

    Falcon Heavy launches quite rapidly. The engines are very strong. Actually they launch at less then full throttle and throttle up a little later so the launch pad is less stressed.

    I don't have very fancy video setup at my computer. Just two monitors. One normal horizontal. A second one vertical so I can display a full page of a document at a good size so I can read it easily.
    Attached Thumbnails Attached Thumbnails Space News thread-octograbber-jpg   Space News thread-ocotograbber-plus-booster-jpg  

  19. #2394
    R.I.P. Luigi's Avatar
    Join Date
    Dec 2014
    Last Online
    @
    Location
    Abuja
    Posts
    26,213
    Dragonfly is off to probe Titan.



    NASA Is Sending a Life-Hunting Drone to Saturn's Huge Moon Titan



    NASA is going to Titan.


    The space agency announced today (June 27) that the next mission in its New Frontiers line of medium-cost missions will be Dragonfly, a rotorcraft designed to ply the skies of the huge, hazy and potentially life-hosting Saturn moon.


    If all goes according to plan, Dragonfly will launch in 2026 and land on Titan eight years later, NASA officials said. The probe will then spend at least 2.5 years cruising around the 3,200-mile-wide (5,150 kilometers) moon, making two dozen flights that cover a total of about 110 miles (180 km).


    The mission is geared toward characterizing Titan's chemistry in detail. Complex organic molecules are known to swirl in the moon's thick, nitrogen-dominated atmosphere, and some scientists think its hydrocarbon seas could host exotic forms of life.
    Titan also hosts another potentially habitable environment — a buried ocean of liquid water, which sloshes beneath the moon's icy crust.


    Dragonfly could conceivably find evidence of Titan life, if the moon is indeed inhabited. And, because Titan is very similar to the early Earth, the mission's observations may shed light on the chemical processes that helped life get going on our planet, NASA officials said.


    "Titan is unlike any other place in the solar system, and Dragonfly is like no other mission," Thomas Zurbuchen, NASA's associate administrator for science at the agency’s headquarters in Washington, D.C


    https://www.space.com/nasa-dragonfly...oon-titan.html

  20. #2395
    Thailand Expat
    Takeovers's Avatar
    Join Date
    Nov 2008
    Last Online
    Today @ 02:44 AM
    Location
    Berlin Germany
    Posts
    7,056
    Quote Originally Posted by Luigi View Post
    NASA is going to Titan.
    A great mission. I am very happy about the decision.

    A video on the mission and how Dragonfly lands there.



    Space News thread-1920px-nasa_dragonfly_mission_to_titan-jpg

    The surface gravity is 0.1352 of Earth, even slightly less than our moon. The atmosphere has about 1.5 times higher density than Earth. This makes flying relatively easy.
    Attached Thumbnails Attached Thumbnails Space News thread-1920px-nasa_dragonfly_mission_to_titan-jpg  

  21. #2396
    R.I.P. Luigi's Avatar
    Join Date
    Dec 2014
    Last Online
    @
    Location
    Abuja
    Posts
    26,213
    ^ I'm kind of disappointed in the animations and images.

    Given how much of Titan is flowing liquid. With lakes and rivers, the promo work is all of dry desert. It also looks very low spec. Like Minecraft or Doom.


    I believe there were also plans for a type of submarine, to dive into the methane lakes, which might have been scraped or been part of another projected mission.


    Personally, I'd love to see the plumes (and fall out) of Europa and Enceladus well sampled.

    But hey, we can't have everything and this is pretty damn cool. Even if I will be 54 or so by the time it actually gets there.

  22. #2397
    Thailand Expat
    Takeovers's Avatar
    Join Date
    Nov 2008
    Last Online
    Today @ 02:44 AM
    Location
    Berlin Germany
    Posts
    7,056
    Quote Originally Posted by Luigi View Post
    I'm kind of disappointed in the animations and images.

    Given how much of Titan is flowing liquid. With lakes and rivers, the promo work is all of dry desert. It also looks very low spec. Like Minecraft or Doom.
    You are making good points I did not even think of. But then they want to make sure not to land in a methane lake. I am sure they will visit one flying later.

    They very sure don't want to go to the area where water geysers are possible. Those are very violent and would destroy the quadcopter immediately.


    Quote Originally Posted by Luigi View Post
    I believe there were also plans for a type of submarine, to dive into the methane lakes,
    I believe you are thinking of another mission. There was thought to send a craft that can melt its way through kilometers of ice to reach the liquid water ocean way below the surface. But that will be beyond our capabilities for a long time yet. There is the problem of providing a lot of energy to melt through kilometers of ice and then maintain contact to the surface to relay results they get when through.

    The quad copter uses an RTG with low power output. Such a mission would require a nucelar reactor. Something like a 10kW kilopower reactor or even bigger and heavier.

  23. #2398
    Thailand Expat
    Join Date
    Oct 2015
    Last Online
    16-07-2021 @ 10:31 PM
    Posts
    14,636
    damn, nobody told me when I was to make that trip

  24. #2399
    R.I.P. Luigi's Avatar
    Join Date
    Dec 2014
    Last Online
    @
    Location
    Abuja
    Posts
    26,213
    ^^ Aren't the methane lakes on the surface, and not under ice?

  25. #2400
    Thailand Expat
    Takeovers's Avatar
    Join Date
    Nov 2008
    Last Online
    Today @ 02:44 AM
    Location
    Berlin Germany
    Posts
    7,056
    Quote Originally Posted by Luigi View Post
    ^^ Aren't the methane lakes on the surface, and not under ice?

    Yes the methane lakes are on the surface. The water ocean is kilometers down.

Page 96 of 161 FirstFirst ... 4686888990919293949596979899100101102103104106146 ... LastLast

Thread Information

Users Browsing this Thread

There are currently 3 users browsing this thread. (0 members and 3 guests)

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •