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34

You throw it in space (in the ISS) just like you would in a room on Earth. It returns to you if it is properly built, and you are capable of properly throwing a boomerang to make it return (this does take some skill.) A returning boomerang will only work in atmosphere - inside a spacestation or on a planet. They depend on aerodynamic forces for the return. ...


19

Like many dehydrated space foods, it's prepared by injecting hot water through a port in an otherwise sealed bag, manually mixing it by massaging the bag, and waiting a few minutes; the noodles are thinner than typical instant noodles so that moderately hot (instead of boiling) water can soften them. As for eating it without spilling, the secret seems to be ...


16

While I don't have a complete answer I thought I'd share what I've found in the hope that someone can come up with something better. I can find nothing online about exactly how and why the visiting vehicle schedule is constructed (Although this could simply be my poor google-fu skills). One thing that is clear is just how tightly packed the schedule is. ...


16

The bolts are part of the Common Berthing Mechanism (CBM). The Common Berthing Mechanism (CBM) is a complex collection of latches, bolts, Ready to Latch (RTL) indicators ... and computers to control this equipment. This system can be operated by either the ground or the crew; extravehicular activities (EVAs) (i.e., spacewalks) are not required to use this ...


12

The return function of a boomerang works in the atmosphere only. Therefore no return in the vacuum of space. The 'arms' of a boomerang are profiled like a airplane wing, but wings do not work without air. (The ISS isn't a vacuum, and so boomerangs "work" in them.)


10

If the package on the right of the lower picture in the question was actually flown, it would have been heated in the Shuttle galley's "food warmer" / "oven". This is because it already contains water and does not need rehydration. Here is a description from the Shuttle Crew Operations Manual. The oven is divided into two principal compartments: an ...


10

I would like to add my own answer based purely on math, which is not as complex as you may think (but I explain each term and everything else so it looks long). We only need a couple equations. First the Tsiolkovsky Rocket Equation: $V_f = V_e \ln(\displaystyle \frac{m_i}{m_f})$ (Soon, we'll need this rearranged for $m_f$, which is $m_f = \displaystyle \...


10

Radiation from the Sun does indeed cause solar panels to deteriorate over time, and powerful single events can lead to a sudden reduction in the efficiency of a solar panel. In 2003, a large solar storm led to an average 3% drop in power for all of EUMETSAT's geostationary spacecraft. We don't really have a good way to "protect" panels from such effects, ...


10

The SS-520-5 launcher is not intended to be an operational vehicle. ... the SS-520-5 was also an experiment to construct a minimum system that can be established with a micro-small rocket and whether future AFSS will be established. ...was conducted as a demonstration of compact and light substrate technology, consumer ...


10

It's all covered by a payload fairing that isn't flush with the body of the spacecraft. A picture is worth a thousand words:


9

They will use the attitude control engines instead of the main engine. JAXA decided to carry out orbit control of the AKATSUKI using its liquid-fuel thrusters for altitude control (or the reaction control subsystem, RCS.) Based on this decision, almost all of the unnecessary oxidizer was discarded in Oct. 2011. As a result, the satellite became lighter, ...


9

The SS-520 lacks the guidance systems that more complex rockets have. It can detect where it is, and what it's attitude is, but can't make as many adjustments as more complex rockets. In order to make it to orbit, it has to start at a slight angle, to allow a gravity turn. Essentially a launched rocket at a slight angle will tend to point more at the horizon ...


8

If JAXA successfully deploys MASCOT, it will be the first lander to use "torque wheel based" propulsion. It is not, however, the first lander to be designed with such a system. JAXA's previous Hayabusa mission had the MINERVA lander on board, which intended to use an "internal fly-wheel assembly" to flick itself across the surface, but it failed to deploy ...


7

Assuming that the design of the parachute was the same as that used on the first Hayabusa, the section you mention is actually netting. The following description of the parachute was given when the first Hayabusa was put on display to the public by JAXA (pdf summary in japanese): パラシュート。強くて軽くてかさばらないポリエステル製の十字形の布でできていて、開くときに絡まないように十字以外の部分はネットが張られています。...


7

It's the Solid Motor Side Jet (SMSJ) system used for roll control - and more! When you look at a picture of the launch, you will see black smoke being discharged from the SMSJ motors. They are ignited 10 seconds before launch, and keep burning until the separation of the first stage. Their role is to control the rocket’s rotation around its central axis, ...


6

The density of carbon dioxide on Venus varies from about 67 kg/m3 at the surface to about 52 kg/m3 at a height of about 5 km, calculated with this software tool Image from Solar Powered Flight on Venus According to the graph above and Appendix A from the article the wind speed on Venus varies from 0.6 m/sec at the surface to 1.2 m/sec at a height of 5 km. ...


6

They're burning off hydrogen in what is called a "flare stack". Probably the hydrogen boiled off from chilling down the engine and/or the hydrogen boiling off from the tank. These dim orange flames are typical hydrogen diffusion flames. The water is there to prevent anything from catching fire. Hydrogen burns pretty hot. Daylight picture: Source JAXA (...


6

Almost certainly. The predecessor H-IIA rocket delivered the orbiter SELENE to the moon in 2007. The SELENE-2 mission slated for 2018 or 2019 will use either an H-IIA or an H-IIB launcher -- it's not entirely clear which from the references I've found, but I think it will be the H-IIA, as the payload is not significantly heavier than that of SELENE.


6

Hayabusa2's Home Position, also known as BOX-A, is a cubic region approximately 1km in size, 20km above Ryugu and directly on the Ryugu-Earth line. We can show that the Home Position is not at any Lagrange points just by checking where they would be for Ryugu. The Hill radius of an object mass $m$ in orbit with semi-major axis $a$ around a body mass $M$ (...


6

Partial answer... Question: What antennas does JAXA use to communicate with its deep space spacecraft? From: https://www.isas.jaxa.jp/en/about/facilities/usuda.html (and mentioned in the comments to the question above) Usuda Deep Space Center was founded to transmit operation commands to deep-space explorers and to receive observation data from explorers. ...


5

The answer is that the Hayabusa-2 was 4.61 km from the SCI when it detonated. The link provides a mission status briefing from JAXA which describes the entire sequence of events, including positions. Slide 10 has the relevant mission data laid out on a grid. http://www.hayabusa2.jaxa.jp/en/enjoy/material/press/Hayabusa2_Press20190411_ver10_en.pdf Before the ...


5

Yes! Update: Thanks to @Sean's answer, I've made an update here as well. From Wikipedia's S-Series_(rocket_family); SS-520-5 The second attempt at becoming the smallest orbital launching rocket was made on 3 February 2018. Liftoff, from the Uchinoura Space Centre, occurred at the opening of a ten-minute window at 14:03 local time (05:03 UTC), successfully ...


5

Searching for "hayabusa 2 thruster specifications" leads me to a paper titled Development and Testing of the Hayabusa2 Ion Engine System. The thruster is called µ10, four of them are used in a single gimbaling mount, and the specific impulse ranges from 2740 s to 2890 s depending on power level. Thrust is 6.3-9.0 mN.


5

According to the JAXA page about the rocket, it's a solid-fuel motor: The propellant, a pre-formed grain, polyurethane composite with a low burning rate... By polyurethane composite I assume they mean HTBP plus ammonium perchlorate and aluminum powder, since that's what JAXA generally uses for solid rockets. Since it's a solid rocket stage, the motor ...


5

There's a good description of the planned landing procedure in the news item, Japan's Hayabusa2 space capsule to fall back to Earth after six-year asteroid mission. Essentially human observers on the ground at Woomera and in the air, combined with radar tracking and the use of a tracking beacon will be used to track and locate the returned capsule. As the ...


4

From the same article, a better photo of the launch site, showing the rocket on its launch rail next to the building: The JAXA site doesn't indicate why the rocket wasn't launched vertically. My guess: most rockets start a pitch maneuver pretty much as soon as they've cleared the tower. This rocket is small enough to be launched from a rail, which means it ...


4

From spaceflight101.com: Hayabusa began firing three of its four ion engines again on January 10, 2018 marking the initiation of the far-field approach phase to take the spacecraft toward its destination with ion engine operation planned to last until early June when the final approach phase will be initiated from a distance of 2,500 Kilometers. [...] ...


4

The "porch" (formally the JEM-EF (Japanese Experiment Module - Exposed Facility)) had a matching connector on it that mated with the connector in the pictures above. This picture shows the shuttle arm holding the JEM-EF and the mating connector. The coarse alignment guides on the two connectors interface with each other; the circles are electrical and data ...


4

To confirm @AlphaD's answer, here are some pictures of peregrine parachute (はやぶさ パラシュート) from a Japanese image search. (Peregrine isn't the kind of parachute, it's English for Hayabusa.) They are called cross-form/cruciform parachutes and are used for payload deliveries. hayabusa 1: hayabusa 2: development version:


4

The standard way to compute the time variation of the orbital elements starts from Lagrange's planetary equations. Other answers on this site which describe them are here, here, and here. These equations don't have any specific answer; they just list the relations among variables in the two-body problem. Think of them as "F=ma" for Keplerian ...


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