The Guild of Icarus: Aerospace Engineering and Aeronautical Club

[morozow]

Valentin Privalov for MIG-17, June 4, 1965. Novosibirsk. This is a photo montage, even though the flight was.

[J. Wilhelm]

So the suspicion is (based on newspaper reports) that the flight did happen but the photo itself is  a hoax with very dramatic imagery, created by someone to post in a newspaper. The real stunt would not have looked so dramatic. http://hoaxes.org/weblog/comments/soviet_pilot_flies_under_bridge

[J. Wilhelm]

Hot from the grapevine (well actually a couple of weeks old)

1: Mexico's National Autonomous University UNAM, announced the start of their own Aerospace Engineering program, I imagine splitting the degree away from the Mechanical Engineering department. This brings the total number of colleges and universities that offer a dedicated Aerospace Engineering program to 12. Last I heard, according to David Dolling, former University of Texas ASE - EM chairman the numbers of Mexican Aerospace graduates has exceeded the same figure for American Universities. In June of last year, UNAM's "High Technology Unit" a graduate department, had signed into the International Astronatics Federation

https://www.gaceta.unam.mx/la-uat-a-la-federacion-internacional-de-astronautica/

However, with the year-old administration of Mexican President A.Manuel López Obrador, "AMLO," it remains to be seen what progress will be made in the aerospace industry, for his administration is somewhat anti-business and he's focused inward toward addressing income disparity in Mexico and has spearheaded a campaign against "Neo-Liberal Economics" which is political jargon for "unbridled capitalism with no government control." The political climate has caused foreign investors to to hold making new inroads into Mexican industry, so hopefully this doesn't result in a glut of engineering graduates unable to find work.


2. In recognition of Mexico's emerging Aerospace industry (design and manufacture of satellites, assembly of executive aircraft, turbine engine design,  commercial aviation electrical systems), Russia's Roscomos space agency signed a cooperation treaty with Mexico's EAS space agency. The treaty will focus on space technology and more specifically satellite applications related to meteorology, ground surveillance for farming, mining and such, and natural disaster warning systems.

https://www.gob.mx/aem/prensa/sumaran-esfuerzos-en-proyectos-espaciales-mexico-y-rusia-230582

Naturally this is a good thing for Mexico and Russia, but not so good for the US. In the past, during the  Cold War, the US' NASA and Mexico's EAS cooperated in all matters of space exploration and technology, but the current political climate between the United States and Mexico is not looking conducive to cooperation (it gives me the impression that only the private US aerospace industry seems to be fully aware of and exploiting Mexican potential). Hence its not a surprise that new doors are opening to other countries' government programs. Something to think about (and I'll stay out of politics after this last sentence).

Mexico's space agency, EAS is much older than people realize. For example, the first Mexican Astronaut was (Payload Specialist , Engineer) Rodolfo Neri-Vela, who flew in 1985 to deliver the second Mexican satellite, "Morelos II" aboard Space Shuttle Mission STS-61B, in 1985.

Mexican satellite Morelos 2,built by Hughes Aerospace is released from
 the payload bay of Space Shuttle Atlantis, mission STS-61B, November 27, 1985.

https://en.m.wikipedia.org/wiki/Rodolfo_Neri_Vela
https://en.m.wikipedia.org/wiki/Morelos_Satellite_System

[Prof Marvel]

In honor and memory of Влади́мир Миха́йлович Комаро́в (Vladimir Mikhaylovich Komarov)

16 March 1927 To 24 April 1967.

Soviet test pilot, aerospace engineer, and cosmonaut. In October 1964, he commanded Voskhod 1, the first spaceflight to carry more than one crew member. He became the first Soviet cosmonaut to fly in space twice when he was selected as the solo pilot of Soyuz 1, its first crewed test flight. A parachute failure caused his Soyuz capsule to crash into the ground after re-entry on 24 April 1967, making him the first human to die in a space flight.

On 26 April 1967, Komarov was given a state funeral in Moscow, and his ashes were interred in the Kremlin Wall Necropolis at Red Square. The American astronauts requested the Soviet government to allow a representative to attend, but were turned down.

I turn over a glass for this heroic Space Pioneer.

Yhs
Prof Marvel

[Antipodean]

In honor and memory of Влади́мир Миха́йлович Комаро́в (Vladimir Mikhaylovich Komarov)
I turn over a glass for this heroic Space Pioneer.

Here - Here!

[J. Wilhelm]

Ooops. The last remnant of the Boeing/Bombardier/Airbus/Embraer Saga ends rather unceremoniously...

If you recall, at the start of the current US administration, Boeing had filed a trade complaint and sued Canada's Bombardier in trade court over their contract to supply Delta Airlines with their C-Series 100 passenger jet. The pretext was that an N. Irish factory which made wing parts for Bombardier was getting sunsidies from the UK government. In reality Boeing wanted to push 737 jets to Delta, but Delta needed smaller planes. Canada responded by cancelling a $6 billion USD order of CF-18s made by Boeing, by raising a law that stated that Canadian companies can't do business with entities that harm Canadian interests (this was still before trade wars erupted globally between the US and other countries).

First flight of Bombardier CS 300 in 2015

A Royal Canadian Air Force CF-18A made by Boeing flies on a mission over Iraq during Operation Impact in 2015

Then as one year rolled by and trade wars heated up, Bombardier apparently was cash strapped (which I understand now has always been normal for that company), and being scared by Boeing's aggression decided to offer their C-Series segment of the business to Airbus. Before Bombardier even found out that they had won their case in US and international trade courts against Boeing, Airbus had already snapped up the C-Series, because as it happens Airbus have factories in the us. Under US law even if you install *one screw* in American soil, that airplane becomes "American-made" - the perfect circumvention to the trade dispute. The losers in that deal were Mexico, really who already had been working on Bombardier's Learjet assembly for many years and now were building electrical systems for the Bombardier C-Series - the electrical system jobs moved to Airbus plants in the State of Georgia in the US.

In July of last year Delta airlines, an American company announced they would no longer purchase Boeing aicraft.
The 737 was one of their favorite planes. Gee, I wonder why? Ever heard of not suing your customers?
https://airwaysmag.com/airlines/delta-receives-last-boeing-future-all-airbus/

Panicked, Boeing sped up a proposed deal to buy a majority stake (80%) of Brazilian company (and major 100 passenger jet market competitor) Embraer, who makes the very succesful E-195, the direct competition to the C-Series (now known as Airbus 220), and presumably the # 1 rivalry in the 100 passenger market (at least in the Americas), and that's not counting their military tanker/cargo plane C-390 Millenium. The idea was to compete against Airbus by taking advantage of lower wages for engineers in Brazil, and turn the civil part of Embraer into "Boeing Brazil," or something like that.

Embraer E-195 started service in 2004 -that's 11 years older than the C-Series!!

Well guess what? Besides Bombardier announcing their late offer of Learjet to Textron this February (thus abandoning all aircraft manufacture - not related to COVID at all), Boeing just cancelled their merger deal with Embraer (this time probably because of COVID). The breakup was ugly, irreverent and callous on Boeing's side, with the dispute between Boeing and Embraer going to arbitration

https://www.bjtonline.com/business-jet-news/boeing-embraer-saga-leaves-sour-taste-in-brazil

The losers now? Everyone. Brazil gets stuck with a non-payment of a $100 million termination fee (in arbitration now). Bombardier is slowly extinguishing, Canada loses a homegrown aerospace company and a chance at big markets, Mexico already lost the C-Series jobs and might even lose all Learjet business to Textron in Texas (assuming that Textron wants to go through with the deal - unlikely at the moment - maybe the Mexican factories are just closed).

Most passenger jets , about 2/3 worldwide are parked now anyways thanks to the COVID 19 pandemic.

https://en.wikipedia.org/wiki/Impact_of_the_COVID-19_pandemic_on_aviation

https://www.bloomberg.com/news/features/2020-04-16/coronavirus-travel-what-happens-to-planes-grounded-by-covid-19

Airbus loses too, but they dominate the market a bit more now on account of them holding the A220...

It makes you wonder if all those lawsuits were worth the paper they were printed on. Don't you think?

[J. Wilhelm]

This is Time Magazine's live coverage of the launch of the manned SpaceX Crew Dragon spacecraft for the Demo-2 / Crew Demo 2 mission. Just tune in, it's T-2 hrs away from right now! This marks the US' return to manned space missions after a whole decade after the Space Shuttle was mothballed.

SpaceX & NASA Launch U.S. Astronauts To Space | TIME

[Deimos]

Almost unbelievable.
I cried.... really, I wept when that rocket lifted off, and then when the first stage separated.
It's been so very, very long in coming, the return to true space exploration. We should have had colonies in the moon by now.
Thank God for visionaries like Elon Musk.

[J. Wilhelm]

Almost unbelievable.
I cried.... really, I wept when that rocket lifted off, and then when the first stage separated.
It's been so very, very long in coming, the return to true space exploration. We should have had colonies in the moon by now.
Thank God for visionaries like Elon Musk.

I can't say that I had the same reaction, but many people did, including my high school buddy who just texted me afteriI sent him a link to the live feed from NASA. He's a tenured college professor teaching history in Mexico City, with whom I watched the first launch of the Space Shuttle Columbia when we were kids. As someone who was inspired into the degree by the 1981 launch of Space Shuttle Columbia, I have a special connection to manned space exploration, even though my soul belonged to Aeronautical flight. The Space Shuttle was unique it combined both disciplines of aeronautics and space flight, so it immediately called my attention. My entire life was filled with the pursuit to understand that machine. But by the time that I finally graduated in 97 I became aware of my capacity for research and I moved from a focus in industry to one in academia.

In all honesty I was not prepared to fully answer the question "how does it work" until two years later in 1999, at which point I had covered everything from atmospheric re-entry through propulsion (aerothermodynamics, hypersonic flight, combustion, etc, etc). Had I not been pulled in that academic direction, I might actually have gone to industry and have caught up with the last few years of the program, in God knows what capacity. Instead, the computational side of hypersonic aerodynamics intensely interested me, and I got to attend several presentations by Lockheed Martin on the X-33 demonstrator (which was a flop - I talk about it somewhere in this thread) during the annual AIAA conferences.

What I did get to do related to the manned space program was have a few Aerospace legends as tutors. The most important perhaps being my orbital mechanics instructor, Hans Mark, a theoretical physicist assigned to be the US Army liaison to Werner Von Braun and his technical team (because he spoke German, as a German migrant to the US and was a physicist by education). Hans Mark was also a former Secretary of the Air Force (1977—79) and Deputy Administrator of NASA (1981-84) during the first Space Shuttle missions.

Anyhow, I think my historian friend was far more exited about the launch than I was. Perhaps back then we were more innocent as kids and the future was so much more brilliant. I did try my hand at joining SpaceX, but my application was rejected in the most irreverent way after only 45 minutes after filing it! Elon Musk (has a degree in Physics) is a visionary, but like all visionaries he's a bit eccentric, shall we say? I used to think that Burt Rutan was a narcissistic weirdo, but Mr. Musk takes the cake. I still think that the world will immensely benefit from Elon Musk's visionary life, though.

[Deimos]

My Dad worked for McDonnell-Douglas his whole life as an EE...designing cockpits for fighters and other "things" (keep reading).
He began working for them in 1950 when it was still McDonnell Aircraft, before they acquired Douglas Aircraft in 1967.

See the Wikipedia entry here and scroll down to Military Aircraft.
If it was built between 1950 and 1980 (the year he died) he worked on it.

He also worked on  space projects Mercury, Gemini and Skylab... was always bringing home photos, drawings , small mockup pieces. Was that legal?...I dunno ...I wasn't even 10 at the time and didn't bother about the ethics of such matters.  

Come 20 July 1969 I was glued to the telly like everyone else around the world.

Except unlike a lot of people, most people in fact, I wasn't awed.  I had been reading SF for 5 years by that time.
All I could think of was "It's about time! Next on the agenda: colonization!"

I really thought that by the time I was in my 50s or 60s one would be able to take a trip to the moon.
Maybe it would be exorbitantly (pun intended) expensive, but at least it would be possible.
But it never happened.
So you may well believe it when I said I wept at a successful Falcon 9 flight.

(And, yes, you don't have to like someone, who may be a first class jerk, to appreciate his genius or vision.)
 

[J. Wilhelm]

In remembrance of Chuck Yeager, RIP (February 13, 1923 – December 7, 2020), I'm posting this Smithsonian documentary on the first supersonic flight.

The Sound Barrier - Bell X-1 / Documentary

[Triztrooper]

Good afternoon. I'm somewhat unfamiliar with the locale. However, Miranda, acting as guide and via the following post...

My goodness, there is a wealth of technical detail to pour over there! May I humbly suggest you add a link to these papers within the metaphysical/meta-clubs/The Guild of Icarus thread so that your fellow engineers here can be aware of, peruse and engage in discourse around their content (whilst enjoying a fine brandy, of course).

Yours,
Miranda.

...directed me to this thread and suggested that I post my particulars. Specifically, Miranda thought you might be interested in the following flying machine which I post for your perusal.

https://gordonhart.substack.com/p/airship-1897

[J. Wilhelm]

Good afternoon. I'm somewhat unfamiliar with the locale. However, Miranda, acting as guide and via the following post...

My goodness, there is a wealth of technical detail to pour over there! May I humbly suggest you add a link to these papers within the metaphysical/meta-clubs/The Guild of Icarus thread so that your fellow engineers here can be aware of, peruse and engage in discourse around their content (whilst enjoying a fine brandy, of course).

Yours,
Miranda.

...directed me to this thread and suggested that I post my particulars. Specifically, Miranda thought you might be interested in the following flying machine which I post for your perusal.

https://gordonhart.substack.com/p/airship-1897

And an interesting machine it is! This very much looks like the developments and diagrams that I had in mind but for an even earlier time period in the 19th C. to allow for the Franco-American Aerial War to happen in my tentative novel "The Valkyrie and the Eagle." Thank you for posting!

[J. Wilhelm]

I don't post here very often, and much less on the subjecty of sailing. But the last time I kept with sailing technology it was the late 1980s and I was a young lad starting college in San Diego, which is what introduced me to the America's Cup and that disastrous international scandal between New Zealand and the United States. The issue being lawsuits back and forth over what kind of technology could be used to meet the race requirements, and after a bitter complaint from the USA over certain technology used by New Zealand, the Americans decided to retaliate by bringing a rigid-sail catamaran as allowed by the loopholes in the vaguely defined rules of the race...

https://en.wikipedia.org/wiki/1988_America%27s_Cup

But after not paying attention to the sailing technology over the last 3 decades, I saw today on NBC Sports Network the latest race beween the UK and Italy in the 2021 Prada Cup which is taking place between January and February of this year (currently ongoing).

https://www.skysports.com/more-sports/sailing/news/30786/12185095/36th-americas-cup-stevie-morrison-talks-development-favourites-and-the-prada-cup

What I saw gobsmacked me. The easiest description of the craft is a racing craft with dual articulated hydrofoils, each *with functional ailerons*, on a hull that acts as a lifting body (airfoil cross-section), naturally a wing plus a sail, and oh yes, the thing can cruise up to 45 knots and turn "on a dime" to tack using said ailerons and rudder. No engine of any kind, just the wind, and the hull barely gets to touch the water.  So there's so much going on that I'm going to post one of the races, and let you marvel at these craft.

Full Race Replay | Day 1 | PRADA America’s Cup World Series Auckland, NZ

[Sorontar]

I remember when Australia II had its legendary winged keel and that was regarded as a such a novel concept. Certainly, the power of the wind can really move you, whatever your craft

Class 5 Land yachts racing and fails on 90 Mile Beach

[J. Wilhelm]

Click on link to go to the live video feed

https://www.nasa.gov/nasalive

[J. Wilhelm]

Today's SpaceX' Starship SN-10 flight test to 10 km altitude (1/8th altitude of von Karman Line, the to "edge of space")

Starship | SN10 | High-Altitude Flight Test

And what they forgot to show you at the end 

Boom! SpaceX Starship SN10 explodes shortly after landing

[Banfili]

Every "Bang!" gets closer to "The Real Thing". The news said it was a planned "Bang!" - is this so? I'd rather a planned bang on earth than an unplanned bang in space!

[J. Wilhelm]

Code:

Every "Bang!" gets closer to "The Real Thing". The news said it was a planned "Bang!" - is this so? I'd rather a planned bang on earth than an unplanned bang in space!

Not planned. They had a CH₄ fuel leak after shutting off the engines. I don't particularly like that big skirt they have around the engines. Gases can be trapped in there. Most byproducts of combustion around the craft after shutting the engines are in intermediary chemical reactions (highly reactive radicals and unfinished combustion compounds, and usually poisonous), which is why even for a hydrogen+oxygen engine like the Space Shuttle, you can't be close for some time after a firing test (there's like 16 intermediary steps between hydrogen + oxygen and water molecules when you burn hydrogen very fast. The only time you go from hydrogen to water cleanly is in hydrogen fuel cells, literally assembling molecule by molecule slowly in aqueous solution - fast hydrogen combustion is very dirty).

[Banfili]

Code:

Every "Bang!" gets closer to "The Real Thing". The news said it was a planned "Bang!" - is this so? I'd rather a planned bang on earth than an unplanned bang in space!

Not planned. They had a CH₄ fuel leak after shutting off the engines. I don't particularly like that big skirt they have around the engines. Gases can be trapped in there. Most byproducts of combustion around the craft after shutting the engines are in intermediary chemical reactions (highly reactive radicals and unfinished combustion compounds, and usually poisonous), which is why even for a hydrogen+oxygen engine like the Space Shuttle, you can't be close for some time after a firing test (there's like 16 intermediary steps between hydrogen + oxygen and water molecules when you burn hydrogen very fast. The only time you go from hydrogen to water cleanly is in hydrogen fuel cells, literally assembling molecule by molecule slowly in aqueous solution - fast hydrogen combustion is very dirty).

I'm glad the launch & flight were successful, anyway. There are obviously some issues, but getting closer with every test. As for the skirt, would vents help, or would they defeat the purpose of the skirt?
The overall design is sort-of an old-fashioned traditional space ship look look, and I like that - it's very comforting that a space ship looks like something out of a science fiction magazine illustration!! I'm reading quite a bit of the more old sci-fi magazine stories at the moment, and although there aren't too many illustrations to go by, some of the cover pictures are grand! Mind you, a lot of the depictions and descriptions of the alien people and creatures are a bit strange!

[J. Wilhelm]

Code:

Every "Bang!" gets closer to "The Real Thing". The news said it was a planned "Bang!" - is this so? I'd rather a planned bang on earth than an unplanned bang in space!

Not planned. They had a CH₄ fuel leak after shutting off the engines. I don't particularly like that big skirt they have around the engines. Gases can be trapped in there. Most byproducts of combustion around the craft after shutting the engines are in intermediary chemical reactions (highly reactive radicals and unfinished combustion compounds, and usually poisonous), which is why even for a hydrogen+oxygen engine like the Space Shuttle, you can't be close for some time after a firing test (there's like 16 intermediary steps between hydrogen + oxygen and water molecules when you burn hydrogen very fast. The only time you go from hydrogen to water cleanly is in hydrogen fuel cells, literally assembling molecule by molecule slowly in aqueous solution - fast hydrogen combustion is very dirty).

I'm glad the launch & flight were successful, anyway. There are obviously some issues, but getting closer with every test. As for the skirt, would vents help, or would they defeat the purpose of the skirt?
The overall design is sort-of an old-fashioned traditional space ship look look, and I like that - it's very comforting that a space ship looks like something out of a science fiction magazine illustration!! I'm reading quite a bit of the more old sci-fi magazine stories at the moment, and although there aren't too many illustrations to go by, some of the cover pictures are grand! Mind you, a lot of the depictions and descriptions of the alien people and creatures are a bit strange!

Vents might help. But if you look at conventional rockets, they don't have skirts. Ever. The bell nozzles are always protruding below the end of the body of the rocket. The closest I can think of is the Soviet Era N1 moon rockets which also used a large number of small engines, but even then, the space under the fuel tank was not so enclosed with a large volume where gasses can accumulate (in my iwn perspective). Even SpaceX' smaller reusable rockets, the smaller Falcon X series, which land in the same fashion, none of them have a skirt around the bell nozzles. Honestly, I don't really know (but do have an idea about) what purpose it serves, whether structural, or otherwise.

One possibility is that it's means as thermal protection for hypersonic re-entry. The Space shuttle has a large spoiler under the aft engines, which serves as both an aerodynamic attitude control device, as well as thermal protection for the engines.

(I miss the Space Shuttle. It will *always" be my "first and only one" reason for studying what I did).

I'm thinking that perhaps the circular skirt is designed to provide protection to the engine nozzle regardless of the axis rotation angle of the rocket when it re-enters the atmosphere. You see, the only thing you have to stop the rocket from rolling about its long axis during atmospheric re-entry are the fin pairs, front and back that each form a "dihedral angle" which is a method to create roll stability in aircraft, At very high altitudes, however, you'll depend on attitude control rockets, because there is very little on the way of aerodynamic forces to help those fins do their job. If the rocket only has that flap in the windward side (belly), and enters the atmosphere "belly up" or "sideways" for whatever reason, the engine nozzles would be unprotected from the plasma flow as the density of the air increases and while the craft stabilizes aerodynamically - I don't know it's a very wild guess on my part, but it's the only thing I can think of.

I understood at the beginning of the project that even with the stainless steel skin, the SN-X rockets would incorporate *some sort* of extra thermal protection system besides the stainless steel skin. But with Musk everything is so mysterious and ever changing and this is such an unconventional rocket. I have not seen any extra thermal protection implemented at all in the SN series of rockets. Quite the contrary, the last time anyone seriously considered metal skins was about 20 years ago with the X-33 Lockheed Martin demonstrator vehicle, which used Inconel slabs bolted over an aluminum mesh around fibreglass tanks. Before the Space Shuttle, steel was considered in the 1960s, during the age of "DynaSoar" lifting bodies, and before that, it was the Silbervogel, a Nazi-Era suborbital bomber design. Metal in general is very difficult to use as a thermal protection system, not only because of the melting temperature, but also because it is chemically reactive with the radical compounds found in the plasma of hypersonic re-entry flows (it literally burns).

I think that this is due to what I heard from Elon Musk, where he was explaining that the re-entry trajectory is unusual in that the vehicle is slowed down as much as possible while staying "above" the atmosphere for as long as possible before "plunging in." The net effect is to reduce the initial airflow speed around the vehicle, which reduces drag (friction) once you plunge in, reducing heat at the skin, and thus allowing for "non-exotic" thermally resistant materials to be used - like stainless steel, as opposed to the Space Shuttle which needs the high performance silica-fibre-based brick and "quilt" system.

I know the Space Shuttle needs to re-enter the atmosphere as quickly as possible to gain positive aerodynamic stability (and control its trajectory to ground in a predictable manner), with its wing(s) and rudder. This means a very "hot" re-entry. AFAIK most re-entry vehicles "want" to re-enter as quick as possible for that reason: control and design of trajectory. But this "Starship" is so big relative to its weight that its body alone may generate enough lift force from the start, thus allowing for a slower re-entry trajectory. Like I said, this is no ordinary rocket, Everything from the manufacture method (welding outside, like water tank), through the materials and mission are different. I just stare at it in fascination. Plus it looks like a Buck Rogers Art Deco rocket, to begin with which is just unreal.

But yeah, they need to work on proper ventilation under that skirt once it's sitting on the ground. Even without a detonation event, the gasses are very toxic.

[J. Wilhelm]

We're getting close to flying a helicopter over the Martian surface.

Here's a briefing from NASA before Sunday's flight.

Ingenuity Mars Helicopter Preflight Briefing

[J. Wilhelm]

It's a very active period for space projects, apparently. After receiving partial support from the government (only $850 million for 2021, well below the target budget of $3.3 billion this year for a lunar program), NASA has selected SpaceX to develop the next lunar lander for the Artemis Program, no doubt in great part because of SpaceX's frugality. However, this is a more complex moon shot program than you may think. To start, the lunar lander, yesterday chosen to be SpaceX' Starship will arrive at the moon using a different platform (SpaceX Super Heavy Booster) than the one that will lift the astronauts (NASA SLS). NASA's Orion spacecraft ferried by SLS will instead take the crew to the SpaceX Starship where astronauts will board, and then use the Starship to land on the moon. And later, when an international space station known as Gateway (NASA / ESA /Jaxa) gets built in a halo orbit (read below), that will serve as a resting area and hub for flights from the Earth to the Moon and Mars... Pretty ambicious.

https://en.m.wikipedia.org/wiki/SpaceX_Starship

https://en.m.wikipedia.org/wiki/Artemis_program#/media/File%3AGateway_Space_Station_Module_Map.jpg

The moon will now be approached from a very different kind of orbit compared to the Apollo program. NASA's SLS launch system will launch the astronauts in the Orion capsule, into what is known as a "halo orbit."  So called because it's almost perpendicular to the line between the Earth and the Moon, looking like a halo above an angel's head; it's path is better described to be like western-movie cowboy's lazo, first approaching the moon, more or less on a straight line, and then taking an unlikely sharp turn to enter into a flattened loop orbit around a point in space, not a celestial body. This can happen, because the spacecraft will be navigating gravitational fields around a Lagrange point, defined as a point in space where all gravitational attraction between the Spacecraft, the Earth and the Moon (or any other three celestial bodies) basically cancels out to zero. The odd thing about these "zero gravity" Lagrangian points is that you can place objects in an unstable orbit around them, along equipotential lines. Think of the Lagrangian point as an "anti-planet" gravity wise.

Explainer: Halo Orbit
https://en.m.wikipedia.org/wiki/Halo_orbit

Lagrangian points and equipotential lines for Sun-Earth-Satellite system
Used to design orbit of Solar and Heliocentric Solar Observatory (SOHO)
NOTE Artemis uses an Earth-Moon-Satellite system.


SOHO's halo orbitPolar view


Equatorial view

The Near Rectilinear Halo Orbit for Artemis III, the first landing on the moon since Apollo.
https://en.m.wikipedia.org/wiki/Artemis_3

https://www.esa.int/Enabling_Support/Operations/Angelic_halo_orbit_chosen_for_humankind_s_first_lunar_outpost

http://youtube.com/watch?v=jfCaac1ijRg&feature=youtu.be

So a Halo Orbit is basically one way to orbit a Lagrange point, instead of a celestial body. It also allows the spacecraft orbiting to be visible from Earth at all times, instead of hiding behind the moon every now and then. It's an unstable (chaotic) orbit, but stable enough with the use of thrusters to keep for a long time. The Near Rectilinear near Halo Orbit (NRHO) chosen for the Artemis Program, basically gets close enough to the moon that you can transfer into a low moon orbit and descend/ascend using less fuel that was used in the Apollo program. Similarly, getting into the NLHO from Earth also takes a lower amount of energy dissipation. The result is that you can get a lander on the moon with less fuel on board for the return trip.

[J. Wilhelm]

Telemetry data received from Mars helicopter Ingenuity confirms that it has successfully performed its first flight.

NASA: First Flight of the Ingenuity Mars Helicopter: Live from Mission Control.
https://www.youtube.com/watch?v=p1KolyCqICI

First image of the shadow of Mars helicopter Ingenuity cast over the Martian surface during its flight. The on-board terrain-tracking camera captured this image.


Still shot from a video of Mars helicopter Ingenuity during its maiden flight. The video was captured by a camera on board rover Perseverance.

[Miranda.T]

Telemetry data received from Mars helicopter Ingenuity confirms that it has successfully performed its first flight.

NASA: First Flight of the Ingenuity Mars Helicopter: Live from Mission Control.
https://www.youtube.com/watch?v=p1KolyCqICI

First image of the shadow of Mars helicopter Ingenuity cast over the Martian surface during its flight. The on-board terrain-tracking camera captured this image.


Still shot from a video of Mars helicopter Ingenuity during its maiden flight. The video was captured by a camera on board rover Perseverance.

That will show those pesky Martians! We'll see how good their tripods are once we can drop pointy things down on them from our fearsome aerial forces!

Re. the SpaceX lunar lander, on a more negative note I read the 2024 dealine has been quiety dropped due to an insufficent budget. Haven't we been here before? Lots of fanfair about returning to the moon, then cost cutting, slipped dates and then the whole thing is shelved. I hope that's not the case, but I worry history is repeasting itself. Again.

Yours,
Miranda.