Zitat Der bekannteste dieser Wanderer findet sich bekanntlich ebenfalls im Umfeld der Götter des Olymp: der Wanderer aus Ithaka, dem, mutatis mutandis, James Joyce vor genau 100 Jahren seinen uferlosen Roman gewidmet hat.
Zum Kostenstand für den "Startturm Nr. 1," Stand Ende Januar 2022:
Zitat von Ars technica, 28 Jan 2022Another launch tower built for the SLS rocket has “encountered some challenges” NASA has issued a "second letter of concern" to Bechtel.
The Space Launch System rocket that NASA has been building for more than a decade now—and which may finally launch for the first time this spring or summer—is rather big. And big rockets need large, complicated ground systems to fuel them and support their launch.
As one might imagine, for a rocket as expensive as the SLS booster—development so far has run in excess of $20 billion and counting—its associated ground systems are quite costly as well.
Much has already been said and written about the first "mobile launch tower" built for the SLS rocket. The massive, rolling Mobile Launcher-1 supports the 108-meter-tall SLS rocket, provides access to the Orion spacecraft, and supplies power, communications, coolant, and fuel to the rocket. Over a decade, NASA spent about $1 billion to build, redesign, and then complete the structure under a cost-plus contract. ... But even though NASA has not yet launched the SLS rocket or shown its capabilities, Congress has already been insistent that the agency develop a larger and more capable version. This "Block 1B" version of the SLS will have a larger and more powerful upper stage. Because this cannot be accommodated by the Mobile Launcher-1, a new launch tower is needed. (That's right—NASA is going to spend $1 billion for some launch infrastructure, Mobile Launcher-1, that may be used just two or three times.) ... Earlier, Bechtel National, of Reston, Virginia, won this contract to design and build the second larger mobile launcher for $383 million by March 2023. Commenting on this development two years ago, Ars Technica wrote, "This would be for about one-third the cost of the first mobile launcher in half the time. Past performance would suggest this is unlikely." That statement has now been proven to be correct.
On Thursday, during a meeting of NASA's Aerospace Safety Advisory Panel, one of its members provided an update on Mobile Launcher-2. George Nield, an engineer and scientist who previously led commercial space transportation for the Federal Aviation Administration, said the 90-percent design, review, and fabrication drawings for the large structure are behind schedule. These are the engineering drawings that should closely represent the final design and inform a construction schedule and logistics plan.
"Mobile Launcher-2 has encountered some challenges," Nield said. "The selected contractor, Bechtel, has experienced some performance issues associated with underestimating the complexity of the project and some supplier related issues, as well as COVID."
In a briefing to the National Academies’ Aeronautics & Space Engineering Board, NASA’s Mike Sarafin says “we’re probably a handful of months or less, ideally two months, away from flying” the Artemis 1 mission.
A big step to make it happen is the next WDR attempt around June 19.
Stephen Clark @StephenClark1
Mike Sarafin, NASA’s Artemis mission manager, says the flight plan for the Artemis 3 mission (first lunar landing) calls for a 6.5-day stay on the moon’s surface with a crew of two, and probably four or five moonwalk excursions.
NASA’s Office of Inspector General has issued its audit on Mobile Launcher 2 and it’s brutal. The contract currently has a value of $460M, but an independent review concludes it will cost nearly $1.5 billion. https://oig.nasa.gov/docs/IG-22-012.pdf
NASA is estimated to spend approximately a billion dollars or at least 2.5 times more than initially planned for the ML-2 contract with final delivery of the launcher to NASA expected to take at least 2.5 years longer than initially planned. As of March 2022, NASA had obligated $435.6 million of Bechtel’s current $460.3 million contract value and extended the contract’s performance period 10 months. However, as of May 2022, design work on the ML-2 was still incomplete and Bechtel officials do not expect construction to begin until the first quarter of fiscal year 2023 at the earliest. To complete contract requirements and deliver an operational ML-2, Bechtel estimates it will need an additional $577.1 million, bringing the structure’s total projected cost to $960.1 million coupled with an October 2025 rather than March 2023 delivery date. We expect further cost increases as inevitable technical challenges arise when ML-2 construction begins. Given the time NASA requires for additional testing once the structure is delivered, the earliest the ML-2 will be available for Artemis IV is November 2026.
Compounding Bechtel’s projected cost increases and schedule delays, an ML-2 project analysis provided only a 3.9 percent confidence level that the nearly $1 billion cost and October 2025 delivery estimates were accurate. NASA requires projects to develop budgets and schedules consistent with a 70 percent joint cost and schedule confidence level (JCL), meaning a 70 percent likelihood the project will finish equal to or less than the planned costs and schedule. In fact, an Independent Review Team analysis determined the project would require an additional $447 million and 27 months, for a total contract value of $1.5billion and a launcher delivery date of December 2027 — a schedule that would enable an Artemis IV launch no earlier than the end of 2028. Further, while the Exploration Ground Systems(EGS) Program, which manages the ML-2 project, established a formal Agency Baseline Commitment (ABC)for the overall EGS Program — the cost and schedule baseline against which a project is measured — NASA has not established a separate ABC for the ML-2, a recommendation we made in our March 2020 report. ... Subsequent to the completion of our audit work, we learned the Agency rated Bechtel's performance for the award fee period ending in March 2022 as "unsatisfactory," resulting in no award fee for this period. Additionally, Bechtel developed a revised interim cost and schedule estimate that projected even higher contract costs and delivery of the ML-2 to NASA in late 2026 — more than 3.5 years later than originally promised. While we did not evaluate Bechtel's revised cost and schedule estimate or award fee rating as part of this audit, we will examine both as we continue to monitor NASA’s management of the ML-2 contract.
Zur Ökonomie Mars / Mond. Tabellen/Graphiken im Thread.
Zitat Dr. Phil Metzger@DrPhiltill More detail on a non-intuitive fact from the Space Resources Roundtable talk this week: to out-compete Earth-launched rocket fuel, the rocket fuel made from lunar or asteroids resources does *not* have to be cheaper. In fact… /1 4:08 AM · Jun 10, 2022 from Alafaya, FL·Twitter for iPhone
2/…it can be a LOT more expensive than Earth-launched rocket fuel and still be competitive. Economists say it like this: it doesn’t need an absolute advantage; it only needs a comparative advantage. Here is the example I thought would be interesting enough to tweet…
3/ To launch humans to the Moon (or Mars since the delta-v is about the same), the SpaceX starship will need about 8 more launches to refuel before leaving Earth orbit. Let’s say the cost per launch gets down to $10M each. So one Moon (or Mars?) mission will cost $90M.
4/ There will be some maximum rate of launches. If Elon wants to settle Mars, the rate will need to be very high. Going slow would be costlier since Mars needs to become as self-sustaining as possible as quickly as possible. Let’s say for a rough example the launch rate is 1/day.
5/ (If they launch every day year-round, the cost is usually much higher due to non-alignment of the planets, but is still do-able for less than a factor of 10 increased cost and acceptably longer transit times, but let’s ignore that since this is just an example of the concept.)
6/ So Elon would not do these launches unless they were providing more value than the money he puts in to do them. What is the value of his life-goal to start civilization on another planet? It is probably infinite return to him. But let’s be utterly conservative & say only 40%.
7/ So if Elon is getting only 40% return of value for his $90M expense for every load of settlers to Mars, that equates to $126M value, or $36M net gain in value, occurring once every 9 days. His profit is thus $4M per day. Now compare using lunar water…
8/ If Starship is refueled using rocket propellant made from lunar (or asteroid) resources, then every Starship launch can carry settlers. Let’s say the lunar propellant costs 20% more than Earth-launched. So each load of travelers requires the same cost as 8 more launches +20%.
9/ That means each launch costs $106M, an increase of $16M compared to Starship bringing all the propellant. But now, Elon gets $126M in value every day, rather than once every 9 days. This yields net profit of $20M per day, which is 5x higher…despite paying 20% more.
10/ In general, the lunar-derived propellant can be as much more expensive than Earth-launched propellant as the value customer attaches to the missions. If Elon sees that settling Mars is worth 200% more than the cost, then the break-even point for lunar water is +200%.
11/ But this is an academic question because as the rest of my talk showed, lunar-derived rocket fuel will quickly become cheaper than Earth-launched. It might take a few years, on the order of 1 to 10 years, for that to happen due to experience curve and economies of scale.
12/ I gave several examples of how it becomes cheaper than Earth-launched. These examples use the following economic factors. 1) Hardware fabrication cost is reduced by optimizing reliability. This depends on launch cost. As launch cost drops, hardware fabrication drops faster.
13/ Second, there is a well-known “experience curve” in industry. The more you have produced, the lower the costs become. Economists have extensive data quantifying this. Wright’s Law is a formula to describe this experience.
14/ Third, as the lunar business grows, it can gain economies of scale. Economists have documented this with extensive data, too.
15/ So here is the first example how these factors will affect lunar rocket fuel production. This first case uses a lunar water mining system that I worked on for a NASA grant in 2019-2020, “Aqua Factorem”.
16/ This case starts in year 1 as cheaper than terrestrial water all the way from the Moon to Geostationary Transfer Orbit, where it can be used to boost telecommunication satellites to their final orbits in GEO. We showed in the NASA study that this business case closes. But…
17/ …it gets even better because by year 14 it is now cheaper all the way to Low Earth Orbit, even though launch costs are dropping as fast as optimists say they will. And this was despite the unfair assumption that the lunar mining had to use much more expensive launch systems!
18/ So let’s get rid of the unfair assumption and use the same projected Starship launch cost for lunar mining. The optimization of reliability shifts because of this, too. The result: even by year 1, lunar water is now cheaper all the way down to Low Earth Orbit.
19/ That is actually too optimistic. There must be a few years of getting the bugs worked out, I am sure. So let’s be super conservative and assume the analysis team’s cost estimates (hardware AND ops costs) were off by a whopping factor of 5…
20/ Actually, I skipped a step. Before we increase costs by a factor of 5, let’s look at the effect of using solar electric thrusters. The case for lunar rocket fuel gets even better.
21/ Now let’s bump the costs a factor of 5 to see what happens if the analysts grotesquely underestimated lunar mining costs. If you only look at year 1, it seems that lunar water cannot compete, not even in low lunar orbit! But lunar water inevitably wins to LEO by year 11.
22/ (In that prior plot, ignore everything after year 10 when the costs start to plummet dramatically. I included an additional factor starting in year 10 in that plot, which I will explain in a moment.)
23/ So let’s try another study besides Aqua Factorem. How about the well-known study by Charania & DePasquale? Skeptics of lunar resources sometimes point to that study to say lunar resources are not competitive anywhere off the Moon. (See: https://trs.jpl.nasa.gov/bitstream/handl....pdf?sequence=1)
24/ I had trouble interpreting parts of that study but did my best to replicate it, and sure enough, it shows that lunar water is not viable off the Moon. But this uses unfair launch costs.
25/ So let’s make just one change to that study. Let’s assume Starship is used to launch the mining hardware to the Moon. Suddenly, lunar water is now out-competing Earth-launched water in successively larger regions of space. But it gets better…
26/ Now let’s use electric propulsion to move the lunar water to its point of sale. (Let’s also add an interest cost for these longer transit times, for completeness, though it has little effect.) Lunar now beats Earth in GTO by year 10. But I think it gets much better…
27/ …because I believe the ops cost estimate is too high at $46M per year for the starter system that produces only 69 t of water per year. I believe that can be reduced a factor or 3 (or more!) if it is a commercial rather than NASA-led operation (no reliability premium).
28/ But even if you take it at face value, lunar rocket fuel is only a small % higher than Earth-launched fuel all the way down to Low Earth Orbit starting in year 1, so by comparative advantage (see start of 🧵) it still wins over Earth-launched fuel everywhere in space.
29/ And so finally, coming back to that extra factor after Year 10 in this plot. Here, I was saying, what if these ultra low transportation costs reach the tipping point to enable new industries in space? (Which will certainly happen.) So…
30/ Let’s assume lunar metal-making enables fabrication of large structures in space rather than launching it all from Earth. And lunar propellant giving cheap boosts helps Space Based Solar Power over the tipping point for broader economic viability.
31/ But it needn’t be SBSP that plays this role. It could be any additional in-space activity that uses rocket fuel. The question is, what happens when lunar mining business doubles due to other products besides water, and when boost services triple above Elon settling Mars?
Zitat von Jun 10, 2022 MEDIA ADVISORY M22-087NASA is targeting Saturday, June 18, for the beginning of the next wet dress rehearsal test of the agency’s Space Launch System (SLS) rocket and Orion spacecraft at the Kennedy Space Center in Florida with tanking operations on Monday, June 20.
During the test, the launch teams will rehearse operations to load propellant into the rocket’s tanks, conduct a full launch countdown, demonstrate the ability to recycle the countdown clock, and drain the tanks to give them an opportunity to practice the timelines and procedures they will use for launch.
NASA will provide live coverage of the test on NASA Television media channel, as well as host media calls before and after the wet dress rehearsal test with audio streaming live on the agency’s website.
Full coverage of the test and associated activities are as follows (all times Eastern):
Wednesday, June 15
11 a.m. – Media teleconference with the following participants:
Jim Free, associate administrator, Exploration Systems Development Mission Directorate, NASA Headquarters Charlie Blackwell-Thompson, Artemis launch director, Exploration Ground Systems Program, NASA’s Kennedy Space Center
To participate by telephone, media must RSVP no later than two hours prior to the start of the event to: firstname.lastname@example.org.
Monday, June 20
7 a.m. – Live coverage of tanking operations with commentary begins
2:40 p.m. – Target test window
Coverage with live commentary throughout tanking operations will air on the media channel of NASA Television, the NASA app, and the agency’s website.
The rehearsal is the final test needed before launch and will begin at 5 p.m. EDT Saturday, June 18 with “call to stations,” when members of the launch control team will arrive at their consoles to start the approximately two-day countdown. On Monday, June 20, the launch director and mission management team chair decide at approximately 7 a.m. if they are “go” or “no-go” to begin tanking the rocket. The team will count down to a targeted two-hour test window that opens at 2:40 p.m. During the test, the team may hold during the countdown as necessary to verify conditions before resuming the countdown, or extend beyond the test window, if needed and resources allow.
Zitat Jeff Foust @jeff_foust In a media call this morning, NASA is confirming plans to proceed with the next SLS wet dress rehearsal, with propellant loading starting around 7 am EDT Monday June 20 and T-0 around 2:40 pm that day, with a two-hour test window.
NASA’s Jim Free, asked about access to information about the WDR (an issue during the April tests), says there will be commentary and “fantastic” graphics for the upcoming test; “we are trying to be more transparent.”
Free: late July/early August window would be “very difficult” to hit for Artemis 1 launch. Looking instead at window in the latter half of August.
The Artemis 1 'wet dress rehearsal' will officially start this evening (June 18).
NASA's Artemis 1 moon rocket will start its "wet dress rehearsal" this evening (June 18), beginning a series of crucial launch countdown tests that will last through Monday (June 20).
If all goes well, the massive Space Launch System (SLS) rocket and Orion space capsule could be headed for the moon before the end of the summer.
The wet dress rehearsal is slated to start today with a call to stations for ground teams at NASA's Kennedy Space Center (KSC) in Florida at 5 p.m. EDT (2100 GMT). Over the course of about 48 hours, the Artemis 1 team will load cryogenic fuel into the huge rocket's first and second stages. If crews don't encounter any complications tonight or tomorrow, propellant loading is scheduled to begin at 7:00 a.m. EDT (1100 GMT) on Monday.
If Monday morning's fuel loading occurs on schedule, NASA is targeting a simulated launch countdown at 2:40 p.m. EDT (1840 GMT). However, NASA has built in an extra two hours to account for any additional testing that needs to take place during propellant loading. Ground teams will load the SLS's core stage first, then move on to the launch vehicle's upper stage, which is called the Interim Cryogenic Propulsion Stage (ICPS).
The countdown has begun. The launch team arrived at their stations at 5pm ET for the #Artemis I wet dress rehearsal attempt. Tanking operations are set to begin on Monday, June 20: https://go.nasa.gov/3aZHAO0
Zitat von June 18, 2022 5:49 pmAt approximately 5 p.m. EDT today, the launch team arrived at their stations inside the Launch Control Center at NASA’s Kennedy Space Center in Florida to begin the wet dress rehearsal test for NASA’s Artemis I mission. The countdown began 30 minutes later at 5:30 p.m. or L-45 hours, 10 minutes before the initial target T-0 of 2:40 p.m. on Monday, June 20.
Overnight, teams will power up the Orion spacecraft and the Space Launch System core stage and prepare the rocket’s four RS-25 engines, which will not be lit during the test.
Weather constraints for propellant loading operations planned for Monday stipulate there must be less than a 20% chance lightning within 5 nautical miles of pad during the first hour of tanking. Winds also must not be above 37.5 knots and the temperature cannot be below 41 degrees Fahrenheit.
NASA is streaming live video of the rocket and spacecraft at Launch Pad 39B and will provide live commentary on the agency’s website beginning with tanking operations on June 20. Activity at the launch pad will likely not be visible during the majority of the countdown, but some venting may be seen during propellant loading.
Zitat von June 19, 2022 4:57 pmMeteorologists with the U.S. Space Force Space Launch Delta 45 currently predict favorable weather conditions for tanking operations on Monday, June 20. Weather constraints stipulate there must be less than a 20% chance lightning within 5 nautical miles of the pad during the first hour of tanking. Winds must not be above 37.5 knots and the temperature cannot be below 41 degrees Fahrenheit.
The mission management team will meet again Monday morning at 6 a.m. EDT or L-8 hours, 40 minutes in the countdown at the beginning of a planned 90 minute built in hold to assess operations and determine whether to proceed with tanking operations.
13:32 MESZ. "Launch Team Working Issue With Backup GN2 Supply - Fueling Ops on Hold"
Monday, June 20 - 1:50 am EDT (05:50 UTC), L-12h 50m, SLS interim cryogenic propulsion stage (ICPS) powered up. - 2:40 am EDT (06:40 UTC), L-12h, All non-essential personnel leave LC-39B. - 6:00 am EDT (10:00 UTC), L-8h 40m, Built-in 90-minute hold begins. - 6:20 am EDT (10:20 UTC), L-8h 20m, Weather & tanking briefing. - 6:50 am EDT (10:50 UTC), L-7h 50m, "Go" / "no-go" poll to begin tanking the rocket. - 7:00 am EDT (11:00 UTC), L-7h 40m, NASA live commentary of tanking operations begins - 7:35 am - 12:40 pm EDT (11:35-16:40 UTC) Core stage and ICPS fueling operations and tests. - 10:20 am EDT (14:20 UTC), L-4h 20m, Orion comm system activation. - 2:00 pm EDT (18:00 UTC), L-40m, Final NASA test director briefing; built-in 30-minute hold begins. - 2:25 pm EDT (18:25 UTC), L-15m, "Go" / "no-go" poll for terminal count. - 2:30 pm EDT (18:30 UTC), T-10 minutes countdown begins for WDR Run 1. - 2:41 pm EDT (18:41 UTC), T-33 seconds, "Cut-off" command automatically executed. Vehicle will be "safed", and recycled back to T-10 minutes for WRD Run 2. Recycling will take about 1 hour. - Approx. 3:40 pm EDT (19:40 UTC), T-10 minutes countdown begins for WDR Run 2.
Zitat NASA's Exploration Ground Systems @NASAGroundSys UPDATE: A valve for the redundant gaseous nitrogen (GN2) line has now been repaired. The launch team is assessing next steps and continue to be in an extended hold. 1:44 PM · Jun 20, 2022·Twitter Web App
Falls die Zeitangaben etwas chaotisch wirken: Ich gebe Lokalzeit, MESZ; die Zeitmarken von Twitter sind am Empfängerende beigegeben; aber in US-Format ante/post meridiem, UTC ist Universal Time = Greenwich-Zeit, mitohne Sommerzeitbeilage.
"Les hommes seront toujours fous; et ceux qui croient les guérir sont les plus fous de la bande." - Voltaire
Zitat ARTEMISS? — We got a leaked look at NASA’s future Moon missions—and likely delays
"Has nobody at NASA read the space policy?"
ERIC BERGER - 6/20/2022, 12:45 PM
For several years now, NASA has publicly discussed the initial phase of its Artemis Moon program. These first three missions, to be conducted over the next four or five years, are steps toward establishing a human presence on the Moon.
The Artemis I mission should launch later this year, testing NASA's Space Launch System rocket and boosting the Orion spacecraft into lunar orbit. The second mission, Artemis II, will more or less be a repeat, only with four humans on board Orion. Then comes the big test, Artemis III, which will send two humans to the Moon and back during the middle of this decade.
Beyond these missions, however, NASA has been vague about the timing of future Artemis missions to the Moon, even as some members of Congress have pressed for more details. Now, we may know why. Ars Technica has obtained internal planning documents from the space agency showing an Artemis mission schedule and manifest for now through fiscal year 2034.
At present NASA has its baseline plan for Artemis, which is shown below. But NASA has also developed at least two "in-guide" schedule options, which agency planners believe are achievable with anticipated budgets, the documents show. These revised schedules indicate that NASA planners do not believe the baseline plan will be achievable on time or within budget.
One of the internal schedules, labeled "cadence," prioritizes launching regularly. The other, labeled "content," prioritizes launching only when the most meaningful payloads are ready. Combined, they reveal that NASA is struggling to cram an ambitious exploration plan into a finite budget. The result is a slow-moving lunar program that, in large part, fails to deliver on the goals of the US National Space Policy.
The schedules show NASA weighing whether to prioritize a regular cadence of missions or more meaningful payloads. Notably, NASA is considering the addition of an "Artemis III.5" mission in the 2027 timeframe to avoid a three-year gap that would otherwise occur. This mission would require a fourth launch of the original version of the Space Launch System rocket, which uses the Interim Cryogenic Propulsion Stage built by United Launch Alliance.
It is likely that this mission would cost about $5 billion and send four astronauts to the small Lunar Gateway, with two going down to the Moon's surface. And there would be other costs. To support the Artemis III.5 mission and evenly distribute the flight gaps, the documents say that NASA would need to delay several Artemis projects, including: Gateway Logistics, both pressurized and unpressurized lunar rovers, a surface habitat, and the Booster Obsolescence and Life Extension program to upgrade the SLS rocket's side-mounted boosters.
Why are there long gaps between missions? One issue is simply financing. With the Artemis Program, NASA is attempting to fit a lot a large, new hardware into a limited budget. Congress has not been overly enthusiastic about funding all of these new programs. The agency also may be concerned that, after launching the core elements of the Lunar Gateway orbital station, additional modules will not be ready to launch until the latter part of the 2020s.
NASA also recognizes that delays are possible with the upgraded version of the Space Launch System rocket, known as Block 1B. This rocket has a more powerful second stage, the "Exploration Upper Stage," which can carry Gateway modules to the Moon along with crew aboard Orion. The new upper stage is far from ready, though, and last week NASA's Inspector General said the massive mobile launch tower used to support it would be years late and substantially over budget. Under the "cadence" schedule proposed by NASA planners, this Block 1B version of the SLS rocket need not be ready until 2029.
Zitat 06/20/2022 16:25 The liquid oxygen flow into the core stage has transitioned to "fast fill" mode, increasing the flow rate of oxidizer into the rocket. The core stage liquid oxygen tank will take nearly three hours to fill with propellant. Up next is liquid hydrogen loading.
NASA has now confirmed the liquid hydrogen load is underway on the Space Launch System’s core stage. The hydrogen is chilled to minus 423 degrees Fahrenheit (minus 253 degrees Celsius), and is currently loading in “slow fill” mode.
The hydrogen flow will transition to "fast fill" mode after 20 minutes in slow fill.
Zitat Jeff Foust @jeff_foust Liquid hydrogen slow fill has now started. They are about 2.5 hours behind the original timeline, which had LH2 slow full beginning at 8:40 am EDT. 5:12 PM · Jun 20, 2022·Tweetbot for Mac
Zitat 06/20/2022 17:31 NASA confirms the liquid hydrogen load has transitioned to “fast fill” on the core stage of the SLS moon rocket. This moves the countdown rehearsal past the point where the launch team detected a hydrogen leak in April.
Zitat Spaceflight Now @SpaceflightNow NASA says the SLS core stage liquid oxygen tank is currently at 38% full, and the liquid hydrogen tank is at less than 5%. Both propellants continue flowing into the Artemis 1 moon rocket at the Kennedy Space Center. 5:36 PM · Jun 20, 2022·TweetDeck
Zitat NASA's Exploration Ground Systems @NASAGroundSys UPDATE: Liquid Oxygen and Liquid Hydrogen fast fill are stable. 46% LOX, 20% LH2. 5:52 PM · Jun 20, 2022·Twitter Web App
18:15: MESZ: O² = 63%; H² = 67%. T minus 3h 52min. 18:35: O² = 78%, H² = 98%. 18:40: O² = 80%, H² = 100% (wird nur noch um den verdampfenden Anteil aufgefüllt). 19:20: O² = 99% (194.546 Gallonen von 196.000); H² = 100% (538.263 Gallonen).
Zitat Spaceflight Now @SpaceflightNow With the core stage fully loaded, NASA’s Artemis launch team is now pumping liquid hydrogen into the Space Launch System’s upper stage. This begins the process to fill the upper stage with about 22,000 gallons of propellant. 7:39 PM · Jun 20, 2022·TweetDeck
20:12: Offensichtlich ist ein Leck in der Wasserstoffzuleitung für die 2. Stufe aufgetreten; in dem Teil der die Verbindung von der senkrechten Leitung im Startturm zur Rakete bildet. 20:18. Ein zweites Problem. Im ICPS (Interim Cryogenic Propulsion Stage) der 2. Stufe gibt es einen zu geringen Druckaufbau beim Betanken mit flüssigem Waserstoff, der unterhalb der erlaubten Parameter liegt. 20:34. Das Druckproblem im ICPS scheint ausgebügelt.
Zitat Spaceflight Now @SpaceflightNow NASA says the Artemis launch team continues to assess a potential hydrogen leak on a core stage quick disconnect. Engineers plan to reduce pressure and resume loading the SLS upper stage with liquid oxygen after a limit was exceeded earlier. 8:41 PM · Jun 20, 2022·TweetDeck
"Les hommes seront toujours fous; et ceux qui croient les guérir sont les plus fous de la bande." - Voltaire
Übertrag, damit der vorige Eintrag nicht ♾️ lang wird.
Zitat NASA's Exploration Ground Systems @NASAGroundSys UPDATE: The team was successful in troubleshooting pressure issues and have currently resumed upper stage LOX fill. The team is pursing a potential fix for the core stage quick disconnect leak. 9:07 PM · Jun 20, 2022·Twitter Web App
Zitat Spaceflight Now @SpaceflightNow The Artemis launch team at the Kennedy Space Center is now loading liquid oxygen into the Space Launch System’s upper stage. This is the last of the four propellant tanks to be filled in this countdown dress rehearsal. 9:38 PM · Jun 20, 2022·TweetDeck
22:00 MESZ. O² für die 2. Stufe ist immer noch im "Fast-Fill"-Modus. 22:32. Der Flugdirektor hat den T-minus-10-Termin abgesagt; der Countdown wird also verlängert für den Versuch, das Problem mit der Wasserstoffzuleitung zu lösen.
23:06. Das ICPS ist die Ableitung für Wasserstoff am Fuß des Rakete; links neben der Startstufe, auf der dem Startturm entgegengesetzten Seite. Die Brennkammern werden durch einen ständigen Strom von flüssigem Wasserstoff gekühlt, um die Temperatur bei der Zündung abzusenken. Dieser Wasserstoff wird dann über das ICPS abgeleitet & außerhalb des Startkomplexes abgefackelt. In dieser Zuleitung ist ein Ventil verklemmt oder verschoben zu sein. Die Flugleitung hat den abgepumpten Wasserstoff auf -60°C zu erwärmen, die Leitung also auszudehnen & dann wieder auf -253°C herunterzukühlen, in der Hoffnung, daß das Ventil anschließend wieder dicht sitzt. Das hat nicht funktioniert; die Flugleitung hat mitgeteilt, daß sie einen weiteren Versuch umternimmt, indem sie die Leitung von außen durch Wasserstoff unter zusätzlichen Druck setzt.
Sollte auch das nicht fruchten, wird der Versuch abgebrochen; O² und H² abgepumpt, die Rakete auf der Startrampe inspiziert & der Versuch evt. am Mittwoch von neuem gestartet. Leiterin des Einsatzteams ist Charlie Blackwell-Thompson.
Zitat Spaceflight Now @SpaceflightNow NASA says the Artemis launch has not succeeded in resolving the hydrogen leak, but managers are discussing continuing the countdown test to around T-90 seconds to gather more data and tick off more milestones for this wet dress rehearsal. 11:06 PM · Jun 20, 2022·TweetDeck
Zitat Spaceflight Now @SpaceflightNow NASA’s Artemis launch team is now discussing resuming the countdown rehearsal and running the clock to T-minus 33 seconds, despite the hydrogen leak in a bleed line in tail service mast umbilical near the bottom of the rocket. 11:42 PM · Jun 20, 2022·TweetDeck
Zitat Spaceflight Now @SpaceflightNow NASA engineers now hope to pick up the Artemis 1 countdown rehearsal — with the hydrogen leak masked from computers to avoid an automatic hold — and run the clock down to T-minus 9 seconds, just prior to when the engines would ignite on launch day. 12:41 AM · Jun 21, 2022·TweetDeck
If the Mission Management Team approves the plan, the Artemis team would only run through the terminal countdown once today. Officials originally wanted to get through the sequence two times.
01:04: "MMT (Mission Management Team) is go for terminal countdown." 01:27: Abstimmung im Führungsteam, ob mit den letzten 10 Minuten des Countdowns fortgefahren wird. Positiv. 01:28: "Terminal countdown has begun."
Wie gesagt: das ein ein kompletter Countodnw mit allem Drum & Dran - nur das am Ende die Haupttriebwerke nicht gezündet werden.
01:35 T minus 3 Minuten. 01:38. Countdown planmäßig bei -29 Sek. angehalten.
01:41. Energieversorgung wieder an den Starttisch übergeben. 01:42: Notstartsystem abgeschaltet.
"Les hommes seront toujours fous; et ceux qui croient les guérir sont les plus fous de la bande." - Voltaire
NASA's Tom Whitmeyer says NASA will take a couple of days to make a final decision on whether to conduct a fifth wet-dress test on the SLS rocket. Reading between the tea leaves, however, it sounds like they're leaning against it.
5:27 PM · Jun 21, 2022·TweetDeck
Todd Versteegh @TLVersteegh·19h The SLS itself achieved all the goals they wanted to get to in the WDR. The issues yesterday were with ground support equipment. The issues can be fixed and tested w/out the need for another full WDR.
BepiColombo ist im Oktober 2018 von Kourou aus gestartet worden; der 1. Merkur-Flyby fand am 1.10.2021 statt. Es folgen ein 4. (5.9.2024), ein 5. und 6. am 2.12.24 & 9.1.25) und ein Einschwenken in den Orbit am 5.12.2025.
Zitat Bepi @ESA_Bepi Feeling the presence of #Mercury as we make our second #MercuryFlyby at just 200 km from its surface!🎢 This gravity assist will slow our velocity in relation to the Sun by about 1.3 km/s. 11:56 AM · Jun 23, 2022·TweetDeck
Zitat Gravitational flybys require extremely precise deep-space navigation work, ensuring that a spacecraft passes the massive body that will alter its orbit at just the right distance, from the correct angle and with the right velocity. All of this is calculated years in advance but has to be as close to perfect as possible on the day.
Getting into orbit around Mercury is a challenging task. First BepiColombo had to shed the orbital energy it was ‘born’ with as it launched from Earth, which meant it first flew in a similar orbit to our home planet – and shrinking its orbit down to a size more similar to Mercury’s. BepiColombo’s first flybys of Earth and Venus were thus used to ‘dump’ energy and fall closer to the centre of the Solar System, while the series of Mercury flybys are being used to lose more orbital energy, but now with the purpose of being captured by the scorched planet.
For this second of six such flybys, BepiColombo needs to pass Mercury at a distance of just 200 km from its surface, with a relative speed of 7.5 km/s. In doing so, BepiColombo’s velocity in relation to the Sun will be slowed by 1.3 km/s, bringing it closer towards Mercurial orbit.
“We have three slots available to perform correction manoeuvres from ESA’s ESOC Mission Control in Darmstadt, Germany, in order to be in precisely the right place at the right time to use Mercury’s gravity as we need it,” explains Elsa Montagnon, Mission Manager for BepiColombo.
“The first such slot was used to tune the desired flyby altitude of 200 km over the planet's surface, ensuring the spacecraft would not be on a collision course with Mercury. Thanks to the meticulous work of our Flight Dynamics colleagues, this first trajectory correction executed very accurately such that further slots were not needed.”
During the flybys it is not possible to take high-resolution imagery with the main science camera because it is shielded by the transfer module while the spacecraft is in cruise configuration. However, BepiColombo’s three monitoring cameras (MCAMs) will be taking photos.
Because BepiColombo’s closest approach will be on the planet’s nightside, the first images in which Mercury will be illuminated are expected to be at around five minutes after close approach, at a distance of about 800 km.
The first images will be downlinked within a couple of hours after closest approach; the first is expected to be available for public release during the afternoon of 23 June. Subsequent images will be downlinked throughout the remainder of the day and a second image release, comprising multiple new images, is expected by Friday morning. All images are scheduled to be released to the public in the Planetary Science Archive on Monday 27 June.
Zitat von June 2, 2022NASA not planning another Artemis 1 countdown dress rehearsal
Forgoing another countdown rehearsal, NASA plans to return the first Space Launch System rocket to its assembly hangar at the Kennedy Space Center next week for a hydrogen leak repair and continued preparations for liftoff on the Artemis 1 moon mission.
With the countdown dress rehearsals complete, ground crews at Kennedy are preparing to roll the 322-foot-tall (98-meter) Space Launch System moon rocket to the Vehicle Assembly Building. The return to the VAB is expected to end the Wet Dress Rehearsal, or WDR, campaign was NASA moves closer to launch of the long-delayed Artemis 1 test flight around the moon, sources said late Wednesday. ... Blevins said Tuesday that engineers would evaluate the risk of proceeding toward launch without getting through the last 20 seconds of the countdown rehearsal. He the worst-case scenario of continuing without another rehearsal is a problem that causes an abort in the final seconds of the countdown on launch day.
“We will have either a successful launch or a scrub because we have protection in the system for those objectives that we didn’t meet, should they not perform properly on launch day,” Blevins said. “So they’re not really about making the vehicle safer to fly. They’re really about can we hit the launch target for our window that’s optimum for our lunar mission.”
Tom Whitmeyer, NASA’s exploration systems manager, said Tuesday that he was “very encouraged” with the outcome of the countdown rehearsal. ... Once the Artemis 1 rocket is back inside the Vehicle Assembly Building, the Artemis ground team will troubleshoot the leaky hydrogen connector detected Monday. Technicians will also complete preparations on the flight termination system, which would be activated to destroy the rocket if it veers off course after liftoff.
Final inspections and closeouts are also on tap inside the VAB, and the ground team will recharge batteries on some of the CubeSat secondary payloads mounted under the Orion spacecraft.
NASA has not set a target launch date for the Artemis 1 mission, but agency officials said last week the earliest the flight could be ready for launch is late August. NASA has Artemis 1 launch dates available in periods lasting about two weeks, when the moon is in the correct position in its orbit, and the trajectory ensures the Orion spacecraft’s power-generating solar panels are not shadowed for more than 90 minutes at a a time.
The next viable Artemis 1 launch period opens Aug. 23 and closes Sept. 6, then more launch opportunities are available beginning Sept. 19.
Zitat NASA eyeing late August for launch of Artemis 1 moon mission
NASA officials have declared the Artemis 1 moon rocket's most recent "wet dress rehearsal" a success and are hopeful the mission can get off the ground as soon as late August.
The Artemis 1 stack — a Space Launch System (SLS) rocket topped by an Orion capsule — is scheduled to roll back to the Vehicle Assembly Building (VAB) at NASA's Kennedy Space Center (KSC) in Florida on July 1, where the massive vehicle will undergo repairs and preparations for its coming launch.
Before it can be rolled back to the VAB, however, the stack will undergo further maintenance at Pad 39B, including repairs to the quick-disconnect component on the aft SLS umbilical, which was responsible for Monday's hydrogen leak.
There's also one more test technicians need to perform at the pad. Hot-firing the hydraulic power units (HBUs), part of the SLS' solid rocket boosters, was originally part of the wet dress countdown but was omitted when the countdown was aborted. Those tests will be completed by Saturday (June 25), according to Lanham. Following the hot-fire tests, operators will then spend the weekend offloading the HBUs' hydrazine fuel.
Once back in the VAB, NASA officials estimate it'll take six to eight weeks of work to get Artemis 1 ready to roll back to Pad 39B for an actual liftoff. Cliff Lanham, senior vehicle operations manager
Zitat Whitmeyer told reporters Friday that the completion of the countdown dress rehearsal campaign this week could allow the SLS moon rocket to be ready for launch during Launch Period 25, which opens Aug. 23 and runs through Sept. 6. “That’s still on the table,” Whitmeyer said.
Another launch period opens Sept. 19 and extends until Oct. 4, followed by three more two-week launch periods through the end of the year. Depending on when the Artemis 1 mission takes off, the Orion test flight could last roughly 26 days or as long as 42 day. The mission duration hinges on the location of the moon relative to Earth, allowing the Orion spacecraft to complete a half-orbit or one-and-a-half distant orbits around the moon.
The launch windows for the Aug. 23-Sept. 6 window are posted below. Aug. 30, Aug. 31, and Sept. 1 not viable launch dates because not all of the launch window constraints are met for those days.
Nächster Schritt der Vorbereitung. Heute Mittag (MESZ) Start des CAPSTONE-Cubesats von Neuseeland, um die Stabilität für den Orbit des geplanten Gateway zu testen.
Zitat NASA’s CAPSTONE mission, which will chart a new orbit around the Moon which will hopefully be used for a future crewed lunar space station, is underway after a successful launch on Tuesday morning. Rocket Lab’s Electron launch vehicle delivered the CAPSTONE satellite, which is roughly the size of a large microwave oven, to Earth orbit for step one of its lunar journey.
The Electron rocket took off from Rocket Lab’s launch facility in New Zealand at 5:55 AM ET, marking Rocket Lab’s 27th flight for its launch vehicle, and its first ever with the Moon as an intended destination. The satellite will remain in low-Earth orbit for around six days, attached to a custom designed Photon upper stage created by Rocket Lab for this mission, after which Photon will ignite its engines a final time to leave Earth’s orbit on a path towards deep space, subsequently releasing CAPSTONE to continue on for arrival at the Moon roughly three months from now.
The goal of the CAPSTONE mission is to use the small satellite to test out a new orbit around the Moon — an elliptical path that will provide a stable enough orbit to maintain a permanent base of operations for excursions to the lunar surface in Gateway, NASA’s planned Moon space station, but also offer a good launch point for deeper space exploration at its furthest point. The lunar Gateway is a key ingredient for NASA’s Artemis program, which will return human astronauts to the surface of the Moon.
Zitat The orbit, which is called a near rectilinear halo orbit, is very elongated and provides stability for long-term missions while requiring little energy to maintain -- which is exactly what the Gateway will need. The orbit exists at a balanced point in the gravities of the moon and Earth.
The CubeSat's orbit will bring the spacecraft within 1,000 miles (1,609.3 kilometers) of one lunar pole at its closest pass and within 43,500 miles (70,006.5 kilometers) from the other pole every seven days. Using this orbit will be more energy efficient for spacecraft flying to and from the Gateway since it requires less propulsion than more circular orbits. The miniature spacecraft will also be used to test out communication capabilities with Earth from this orbit, which has the advantage of a clear view of Earth while also providing coverage for the lunar south pole -- where the first Artemis astronauts are expected to land in 2025.
Spoke with Jim Free at the Moon to Mars Objectives workshop in Houston. He said NASA is targeting the August 23 to September 6 period for the Artemis I mission. Teams have firm plans for what to do in the VAB and then get back to the pad in August. 🚀
Zitat Watch NASA roll huge Artemis 1 moon rocket off the pad early Friday
By Mike Wall published 16 minutes ago
Rollback is expected to begin at midnight EDT (0400 GMT) on Friday (July 1).
NASA plans to start rolling its Artemis 1 moon mission off the launch pad early Friday morning (July 1), and you can watch the slow-moving action live.
The Artemis 1 stack — a Space Launch System (SLS) rocket topped by an Orion crew capsule — is expected to depart Pad 39B at NASA's Kennedy Space Center (KSC) in Florida at midnight EDT (0400 GMT) on Friday. The duo will head toward KSC's cavernous Vehicle Assembly Building (VAB), making the 4-mile (6.4 kilometers) trip in 10 hours or so atop NASA's enormous crawler-transporter 2 vehicle.
You can watch at least some parts of the rollback live here at Space.com, courtesy of NASA. The agency will provide webcast coverage (opens in new tab) "of the rocket departing the launch pad and arrival at VAB," NASA officials wrote in a recent update (opens in new tab).
Zitat NASA's Kennedy Space Center @NASAKennedy Teams have rescheduled the return of the @NASA_SLS rocket and @NASA_Orion spacecraft to the VAB to Friday, July 1 due a concern with the condition of the crawlerway that leads from Launch Pad 39B to the VAB. First motion is now planned for 6pm EDT. 1:11 AM · Jul 1, 2022·Twitter for iPhone
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