Dragon v2 (SpX-DM2) – Falcon 9 (B1058.1) – Kennedy LC-39A – 27.05.2020, 20:32 UTC

[tnt22]

https://blogs.nasa.gov/spacestation/2020/05/15/japanese-cargo-spacex-crew-dragon-activities-ramping-up/

Japanese Cargo, SpaceX Crew Dragon Activities Ramping Up
Mark Garcia
Posted May 15, 2020 at 11:22 am


NASA astronauts Bob Behnken (left) and Doug Hurley participate in a fully integrated test of SpaceX Crew Dragon flight hardware at the SpaceX processing facility in Florida on March 30.

The International Space Station is getting ready for a new Japanese cargo mission and the first Commercial Crew before the end of the month.
...
Two days after the arrival of Japan's HTV-9 resupply ship, the first crew to launch from U.S. soil since 2011 will lift off from Florida to the orbiting lab aboard the SpaceX Crew Dragon vehicle. NASA astronauts Bob Behnken and Doug Hurley are in preflight quarantine at the Kennedy Space Center counting down to their May 27 launch at 4:33 p.m.

The veteran astronauts, representing NASA's Commercial Crew Program, will approach the station May 28 and dock to the Harmony Module's forward-facing International Docking Adapter at 11:39 a.m. They will open the hatch about two-and-a-half hours later to join the Expedition 63 crew and ramp up space science activities.

[tnt22]

Space to Ground: Fanning the Flames: 05/15/2020

NASA Johnson

15 мая 2020 г.

https://www.youtube.com/embed/Ku9av0g7v9U?feature=oembed (2:52)

[tnt22]

https://spaceflightnow.com/2020/05/12/dragon-solar-array-concerns-driving-duration-of-first-crewed-test-flight/

Dragon solar array concerns driving duration of first crewed test flight
May 12, 2020 | Stephen Clark


Artist's concept of a SpaceX Crew Dragon capsule docked at the International Space Station. Credit: SpaceX

NASA astronauts Bob Behnken and Doug Hurley will be geared up for the long haul when they launch fr om the Kennedy Space Center on a SpaceX Crew Dragon spacecraft later this month, but they won't know exactly how long they will be in orbit until they are already aboard the International Space Station.

The Dragon astronauts, both veterans of two space shuttle missions, could live and work on the space station for one to four months, according to NASA officials. The duration will primarily hinge on how well the Crew Dragon's solar panels hold up in the harsh environment of space.

"The minimum mission duration is really about a month, and the maximum is 119 days," said Steve Stich, deputy manager of NASA's commercial crew program.

The Crew Dragon test flight — set for liftoff at 4:33 p.m. EDT (2033 GMT) May 27 — will be the first launch of astronauts into orbit from the Kennedy Space Center since July 8, 2011, when the shuttle Atlantis rocketed into space on the final flight of the space shuttle program.

If the mission launches May 27, the Crew Dragon is scheduled to autonomously dock with the International Space Station at 11:39 a.m. EDT (1539 GMT) May 28. Behnken and Hurley originally planned to fly to the space station for no more than a couple of weeks after launching on a SpaceX Falcon 9 rocket.

The purpose of the Crew Dragon demonstration flight, named Demo-2 or DM-2, is primarily intended to test the commercial crew ship's performance with astronauts on-board. It follows a six-day unpiloted Crew Dragon test flight to the space station in March 2019.

But NASA has approved an extension to the Demo-2 mission. Faced with the prospect of a period of months with just one U.S. astronaut aboard the space station — limiting opportunities for maintenance and repair spacewalks, and restricting the station's scientific output — NASA is planning to keep Behnken and Hurley at the $100 billion orbiting research outpost for up to four months.

NASA astronaut Chris Cassidy launched from Kazakhstan on a Soyuz rocket April 9 with two Russian crewmates.

"This launch will allow researchers around the globe to work with astronauts on-board the space station to undertake many different scientific investigations," said Kirk Shireman, NASA's space station program manager at the Johnson Space Center in Houston. "The SpaceX crew, with Chris Cassidy already on-board the International Space Station, will be doing experiments on physiology, cardiovascular experiments, physical and life sciences, testing out life support systems ... and testing out habitation experiments for our future human space exploration."

Behnken could also join Cassidy in a series of spacewalks to replace batteries on one of the space station's solar power trusses. The new lithium-ion batteries will be delivered to the space station later this month on an automated Japanese HTV supply ship.

...

The Russian Soyuz capsule has been the only spacecraft capable of carrying crews to the space station since the space shuttle program ended. NASA has paid the Russian government approximately $3.9 billion since 2006 to purchase Soyuz seats for astronauts from the United States and the station's other international partners, according to a report last year by NASA's inspector general.

NASA expects to end payments to Russia once the new U.S. crew ships are operational. Under the space agencies' current plans, U.S. astronauts will continue flying on Soyuz spacecraft and Russian cosmonauts will launch and land on the new U.S. vehicles under a barter arrangement, with no funds exchanged.

But Russian officials say they are not assigning cosmonauts to missions on U.S. vehicles until they are flight-proven.

Flush with NASA money, Russian space contractors doubled the production of Soyuz crew capsules for launches beginning in 2009 to meet the demand for astronaut transportation to the space station. After NASA's last Soyuz seat purchase in 2017, the schedule for Soyuz crew missions has been cut back to two flights this year.

Cassidy took the last Soyuz seat under NASA's control, but the agency is negotiating to purchase one more round-trip Soyuz ticket  for a launch in October.

NASA and SpaceX hope the first operational Crew Dragon mission, designated Crew-1, could be ready to launch some time this fall. But NASA wants a backup plan to ensure a U.S. astronaut can get to the space station in case of additional delays.

Regular crew rotation flights using the Crew Dragon capsule could last up to 210 days, but NASA and SpaceX are setting tighter limits for Behnken and Hurley's mission due to the experimental nature of the Demo-2 test flight.


NASA astronauts Doug Hurley and Bob Behnken address the media in October 2019 at SpaceX headquarters in Hawthorne, California. Credit: NASA/Aubrey Gemignani

Stich said preflight analyses show the Crew Dragon spacecraft set to fly the Demo-2 mission can safely remain in orbit for up to 119 days, or about four months, based on a "worst-case" prediction for how the ship's solar arrays will perform in orbit.

"Any solar array in low Earth orbit tends to degrade a little bit over time," said Stich, a former space shuttle flight director. "It turns out the atmosphere has a little bit of oxygen in it — it's called atomic oxygen — so there's a little bit of degradation in the ability of that solar array, the cell itself, to generate power."

Once the Crew Dragon is docked to the space station, SpaceX and NASA engineers will assess data the solar arrays' performance and efficiency to determine when to bring the crew back to Earth.

"What we'll do is we have this curve of what we expect that degradation to be over time," Stich said. "We can kind of look at the power the arrays generate each day, and kind of plot that against this prediction, and that can give us the overall total capability."

The solar arrays on SpaceX's new-generation Dragon spacecraft, called Dragon 2 or Crew Dragon, are mounted on the body of the spaceship's unpressurized trunk. The trunk is attached to the aft end of the Dragon's pressurized crew cabin, and a thermal radiator sits on the opposite side of the cylindrical trunk from the solar arrays.

SpaceX's previous Dragon design, which retired earlier this year after 20 unpiloted cargo delivery flights to the space station, used unfolding solar panels to generate electricity.

"We looked at the rest of the vehicle, (and) we don't see any other life limiters," Stich said in a May 1 press conference. "We looked at the pumps on the thermal system, we looked at the propulsion system, all the other components, when we talked about extending the mission, and the solar arrays are the only one really that have a little bit of a poke-out.

"So we'll just kind of watch their performance in flight and be able to make a good decision about how long to stay docked," he said.

NASA is balancing the objectives of the Demo-2 test flight with satisfying the agency's desire for extra manpower on the space station.

"We're really trying to do both a test flight with this vehicle, and also have the vehicle docked to station to allow Bob and Doug to augment the station crew," Stich said.

Hurley, the Demo-2 spacecraft commander, said the unknown mission duration is one of the challenges of preparing for the trip to the space station.

"I think that's more of a human element," Hurley said. "We go in it knowing that it could be 30 days up to four months, and it'll probably end up being somewhere in between that. But that's certainly an unknown, from a personal standpoint, that you'd like to maybe have a little bit better answer for, but we certainly understand the reasons why, and I think hopefully we'll be able to offer some good support to Chris Cassidy, who's up there in the U.S. segment on his own right now."

Officials will also look at the schedule for the following Crew Dragon flight, which will carry four astronauts to the station, when deciding on a schedule for Behnken and Hurley's return to Earth. And mission managers will assess weather and sea conditions in the Dragon's splashdown zone roughly 27 miles (24 nautical miles; 44 kilometers) off Florida's East Coast.

The Dragon demonstration flight will mark the first time astronauts have climbed into a newly-designed spaceship and launched into orbit since 1981, when the first space shuttle took off from pad 39A, the same historic launch complex wh ere Behnken and Hurley will launch later this month.
...

[tnt22]

https://spaceflightnow.com/2020/05/13/back-to-back-launches-scheduled-from-cape-canaveral-this-weekend/

Back-to-back launches scheduled fr om Cape Canaveral this weekend
May 13, 2020 | Stephen Clark

Working under physical distancing requirements and other precautions against the coronavirus pandemic, range teams at Cape Canaveral are preparing for launches of Atlas 5 and Falcon 9 rockets from neighboring pads this weekend.

The back-to-back launches are scheduled for Saturday and Sunday from Cape Canaveral Air Force Station, hauling up the U.S. Air Force's X-37B spaceplane and another batch of around 60 satellites for SpaceX's Starlink Internet network. ...

The two launches this weekend will be followed by the liftoff of two NASA astronauts atop a Falcon 9 rocket from NASA's Kennedy Space Center adjacent to Cape Canaveral Air Force Station. That will be the first launch of astronauts from Florida's Space Coast since the last flight of the space shuttle in July 2011.

"In our partnership and SpaceX ... we are excited for the return of human spaceflight from the Eastern Range, Cape Canaveral, Kennedy Space Center and the Space Coast on May 27 for the SpaceX crew mission," Schiess said.

In addition to the usual safety, weather forecasting and security support it provides for all missions from the Space Coast, the 45th Space Wing will host an emergency team that would be dispatched to rescue the astronauts in the event of a launch abort. In such a scenario, the rescue personnel would fly offshore on military helicopters and transport planes and parachute into the Atlantic Ocean to meet the astronauts.

"Our Detachment 3, which has been re-designated for this event as Task Force 45, is preparing to be able to rescue astronauts if for some reason there was a catastrophic event," Schiess said. "We don't think that will happen, and we hope that it never does, but we are preparing for the possibility and being prepared to do that."

...

Schiess said that the range recently assessed the possibility of launching two SpaceX missions within six hours from different launch pads. That appears feasible with two rockets that use autonomous flight safety systems, Schiess said.

...

NASA Administrator has urged people not to travel to Florida's Space Coast to view the crewed launch May 27, and the Kennedy Space Center will not allow the public to access the closest viewing sites. Schiess said the 45th Space Wing is following a similar policy.

While Kennedy and Cape Canaveral are two different installations, they are joined, so we make sure we're doing things together," he said. "Right now, they're in the status wh ere they won't have any public viewing, so we won't have any public viewing or placard viewing at Cape Canaveral Air Force Station at this time for the May 27 (crew) launch."

...

The Falcon 9 launch this weekend is the final planned SpaceX mission before the Crew Dragon demonstration flight launching May 27.
...

[triage]

https://spacepolicyonline.com/news/no-checkered-flag-yet-but-commercial-crew-getting-closer-to-finish-line/

NO CHECKERED FLAG YET, BUT COMMERCIAL CREW GETTING CLOSER TO FINISH LINE
By Marcia Smith | Posted: May 14, 2020 11:55 pm ET | Last Updated: May 14, 2020 11:59 pm ET
...
Once Crew Dragon is docked to ISS, McAlister said they will put four crew members inside to see how they fit. That means a Russian cosmonaut will be among the occupants.
...

[cross-track]

cross-track написал:
 

Not написал:
Интересно, а внедорожные катафалки Тесла выпускает, с фирменными нашлепками? Надо все случаи предусмотреть.

Какие случаи?

Видимо, ответа не будет.

[tnt22]

https://spaceflightnow.com/2020/05/16/crew-dragon-capsule-meets-falcon-9-rocket-inside-launch-pad-hangar/

Crew Dragon capsule meets Falcon 9 rocket inside launch pad hangar
May 16, 2020 | Stephen Clark


Artist's illustration of SpaceX's Crew Dragon spacecraft. Credit: SpaceX

SpaceX transferred the first astronaut-ready Crew Dragon spacecraft Friday night fr om a fueling facility at Cape Canaveral Air Force Station to pad 39A at NASA's Kennedy Space Center, where teams will join the capsule with its Falcon 9 launcher for liftoff later this month.

The spacecraft arrived at the pad 39A hangar late Friday night, according to Kyle Herring, a NASA spokesperson.

Before its transport by road to the Falcon 9 hangar, the Crew Dragon capsule's propulsion system was loaded with hypergolic hydrazine and nitrogen tetroxide propellants inside a fueling complex a few miles south of pad 39A at Cape Canaveral Air Force Station.

The propellants will feed the Crew Dragon's Draco in-space maneuvering thrusters and high-performance SuperDraco escape engines, which would only be activated in the event of an emergency during launch.

Liftoff of the Crew Dragon test flight — the first U.S. mission to send astronauts to Earth orbit since 2011 — remains scheduled for May 27 at 4:33 p.m. EDT (2033 GMT) to kick off a 19-hour pursuit of the International Space Station.

In the coming days, SpaceX ground crews will verify mechanical and electrical attachments between the Crew Dragon spacecraft and the Falcon 9 launcher inside the hangar. Then the entire vehicle, measuring some 215 feet (65 meters) tip to tail, will be lifted by a crane and placed onto SpaceX's rocket transporter for the quarter-mile journey up the ramp to the deck of pad 39A.

The Falcon 9 launcher assigned to the Crew Dragon's first piloted test flight — designated Demo-2 or DM-2 — is an all-new vehicle. SpaceX regularly lands and reuses rocket boosters to cut costs, but NASA has required SpaceX to assign new first stages to at least the initial launches that carry astronauts.


The Falcon 9 rocket that will launch the Demo-2 mission is emblazoned with NASA's "worm" logo, which was retired fr om official use in 1992. Credit: SpaceX

The first stage booster for the Crew Dragon's Demo-2 mission is emblazoned with NASA's "worm" logo, which spells out "NASA" in stylized lettering. The worm logo was introduced in 1975 to add a touch of modernity to the agency's public image after the last of NASA's Apollo moon landings, which took place when NASA used its original blue "meatball" symbol.

The worm logo was retired in 1992, and NASA removed the iconic interconnected lettering from signs, brochures, and even the agency's space shuttles. The original meatball, first designed in the late 1950s, again became NASA's official logo.

"The worm is back," NASA announced last month. "And just in time to mark the return of human spaceflight on American rockets from American soil."

In a statement, NASA said "the retro, modern design of the agency's (worm) logo will help capture the excitement of a new, modern era of human spaceflight."

The memorable worm insignia — with its stark red logotype — will make its first public appearance on a NASA-sponsored rocket in nearly 30 years when the Falcon 9 launcher emerges from the hangar next week and rolls out to pad 39A.

Once the vehicle is vertical on the launch pad, SpaceX will run the Falcon 9 rocket through a fueling test and a test-firing of its Merlin main engines next week.

At the same time ground teams work on flight hardware at Cape Canaveral, NASA astronauts Doug Hurley and Bob Behnken are in quarantine at their homes in Houston before they travel to the Kennedy Space Center on Wednesday aboard a NASA Gulfstream jet.


File photo of SpaceX's hangar at pad 39A, with a Falcon Heavy rocket in the background. Credit: Stephen Clark/Spaceflight Now

The astronauts are both veterans of two space shuttle flights, and they started working full time on NASA's commercial crew program in 2015. In 2018, NASA assigned Hurley and Behnken to the Crew Dragon's first flight with astronauts.

After arriving at the spaceport in Florida on May 20, the astronauts will receive mission briefings, brush up on procedures, and perform fit checks with their SpaceX-made launch and entry flight suits. They are also scheduled to take questions from reporters in a press conference Wednesday at Kennedy soon after they arrive in Florida, then in a virtual news briefing Friday, May 22.

If activities next week go according to plan, the astronauts will run through a launch day dress rehearsal next Saturday, May 23.

The two-man crew will suit up and ride inside a Tesla Model X from the Operations and Checkout Building at Kennedy to launch pad 39A, wh ere they will ride an elevator to the 265-foot-level of the pad's fixed tower. They will then walk across SpaceX's crew access arm to the white room, wh ere a closeout team will help them board the capsule.

Hurley, the 53-year-old Dragon spacecraft commander, will strap into the left seat of the capsule. Behnken, 49, will take his place in the right seat for the pre-launch simulation.

The "dry dress rehearsal" is meant to give the astronauts and their support teams a feel for the flow of launch day.

Amid the hardware preps and crew activities, NASA and SpaceX managers plan to convene a pair of major reviews before the Crew Dragon launch to ensure the spacecraft, the rocket, the astronauts, ground systems and the International Space Station are ready for the test flight.

A Flight Readiness Review is scheduled May 21, followed by a Launch Readiness Review May 25.

"There's still work to be done," said Phil McAlister, head of NASA's commercial spaceflight development mission. "We're still finishing up some final testing. There's still some documents we have to review."

"The Flight Readiness Review on the 21st is a very big milestone," McAlister said Thursday in a briefing to the NASA Advisory Council's Human Exploration and Operations Committee. "That's going to be when we we all get together one last time and say whether we are ready for flight. So that will be a huge, huge milestone."

[Феликс]

Блин а до Worm logo какой был   
? 
Я почему то думал что он и был... 
(живу реалиями 92 года оказывается) 

[opinion]

Феликс написал:
Блин а до Worm logo какой был  
?
Я почему то думал что он и был...
(живу реалиями 92 года оказывается)  

Сначала была "фрикаделька" (синий круг со звездами, надписью NASA и  стилизованным крылом). Потом появился червячок - просто стилизованная надпись NASA. Кажется, примерно вместе с шаттлами.

Пару лет назад решили отказаться от червячка и вернуть фрикадельку. Ностальгия, типа. Теперь и червячка тоже вернули. Типа, ностальгия.

[Александр Репной]

С нетерпением жду исторического старта! Надеюсь, всё пройдёт, как по учебнику!

[opinion]

tnt22 написал:
 

SpaceX  @SpaceX   ·  10 мин. назад

Simulator of Crew Dragon docking with  @space_station
 →  http://iss-sim.spacex.com

Неудобный интерфейс. Надеюсь, Дракон пристыкуется автоматически.

[cross-track]

opinion написал:
 

tnt22 написал:
 

SpaceX  @SpaceX   ·   10 мин. назад  

Simulator of Crew Dragon docking with   @space_station  
 →   http://iss-sim.spacex.com  

Неудобный интерфейс. Надеюсь, Дракон пристыкуется автоматически.

Чем неудобный? Я, хоть играми не увлекаюсь от слова вообще, на этом симуляторе состыковался с первой попытки. Имхо, все наглядно, понятно и дружелюбно.

[Not]

cross-track написал:
 

cross-track написал:
 

Not  написал:
Интересно, а внедорожные катафалки Тесла выпускает, с фирменными нашлепками? Надо все случаи предусмотреть.

Какие случаи?

Видимо, ответа не будет.

Я поясню тебе, в чем проблемы. Снаружи все великолепно-сверкающее, а внутри непойми что. Внутри Дракона, в который драконавтам лезть тонна вонючки, причем летает она с ними вплоть до приземленя, потому что Маску когда то хотелось красиво реактивно сажать. Хотелки прошли, а гидразин остался. NASA могло бы послать его нах переделывать, но видимо духу не хватило. Так что речь о катафалках вполне себе актуальна.

[cross-track]

Not написал:
 

cross-track написал:
 

cross-track  написал:
   

Not   написал:
Интересно, а внедорожные катафалки Тесла выпускает, с фирменными нашлепками? Надо все случаи предусмотреть.

Какие случаи?

Видимо, ответа не будет.

Я поясню тебе, в чем проблемы. Снаружи все великолепно-сверкающее, а внутри непойми что. Внутри Дракона, в который драконавтам лезть тонна вонючки, причем летает она с ними вплоть до приземленя, потому что Маску когда то хотелось красиво реактивно сажать. Хотелки прошли, а гидразин остался. NASA могло бы послать его нах переделывать, но видимо духу не хватило. Так что речь о катафалках вполне себе актуальна.

У меня была небольшая надежда, что ты скажешь, что оговорился, что неудачно пошутил. Но не сложилось. Я не буду тебе объяснять, что ты можешь не соглашаться с техническими решениями, считать их рискованными и т.п., но перед полетом, одобренным, кстати, твоим любимым НАСА, "шутить" про катафалк можно на помойке, а в приличном обществе так не шутят. Теперь я понял, чтО ты будешь ожидать от испытательного полета американских астронавтов, и надеюсь, что твои влажные мечты не осуществятся.

Ты можешь мне ответить, можешь не отвечать, но тебе с этого момента я отвечать не буду.

[Not]

cross-track написал: но перед полетом, одобренным, кстати, твоим любимым НАСА, "шутить" про катафалк можно на помойке, а в приличном обществе так не шутят.

Сэр, это не шутки. Я бы этот корабль к астронавтам NASA на пушечный выстрел не подпускал, по его конструктивным особенностям, определенным сиюминутными коньюнктурными соображениями. Спейсекс собиралась тащить его на Марс, в рамках проекта Красного Дракона, и убедила всех вокруг, что им иначе жить нельзя. Окей, с ними согласились, и был построен Дракон пилотируемый с данными архитекрными излишествами. Но потом ветер в Спейсекс изменился, и они решили что нефиг мелочиться, нужно строить сразу стальной звездолет, и Драгон пошел у них вторым номером. Естественно, что никто ничего переделвывать на стал. И теперь это потенциально опасное решение повезет астронавтов. Я не знаю, какими политическими соображениями руководствуется Администратор НАСА, но он совершает большую ошибку. И это уже не шуточки. Хуже того, они умудрились наглядно продемонстрировать что будет если этот гидразин взорвется. Бранденстайн в ответ промямлил -что дескать для того мы тестируем. Расплываться в елее, дескать ах, дескать наконец то американский корабль конечно можно, но это не ко мне. Физику не обманешь.

[Alex_II]

Not написал:
Сэр, это не шутки. Я бы этот корабль к астронавтам NASA на пушечный выстрел не подпускал,

Слава Одину, что не ты этим рулишь чмо убогое с психическими проблемами...

[Not]

Alex_II написал:
 

Not написал:
Сэр, это не шутки. Я бы этот корабль к астронавтам NASA на пушечный выстрел не подпускал,

Слава Одину, что не ты этим рулишь чмо убогое с психическими проблемами...

В зеркало загляни, дружище! И последи за язычком, он тебе заведет опять не туда.

[Alex_II]

Not написал:
В зеркало загляни, дружище!

Не прокатит полудурок. Меня (видимо в отличие от тебя) каждый год на комиссию к психиатру гоняют - у меня работа опасная, положено... А вот по тебе уже вся психушка обрыдалась - никак не могут дождаться когда же этот тупой маскохейтер и боингодрочер к ним наведается - это ж целая докторская диссертация на воле еще бегает...

[STS]

Alex_II написал:
Меня (видимо в отличие от тебя) каждый год на комиссию к психиатру гоняют - у меня работа опасная, положено...

хреновый какойто психиатр

[opinion]

cross-track написал:
 

opinion написал:
 

tnt22  написал:
   

SpaceX  @SpaceX   ·    10 мин. назад  

Simulator of Crew Dragon docking with    @space_station  
 →    http://iss-sim.spacex.com  

Неудобный интерфейс. Надеюсь, Дракон пристыкуется автоматически.

Чем неудобный? Я, хоть играми не увлекаюсь от слова вообще, на этом симуляторе состыковался с первой попытки. Имхо, все наглядно, понятно и дружелюбно.

Может быть, это только у меня так?

Знаки отклонений по углам и угловых скоростей противоположные. При отрицательной угловой скорости абсолютное значение угла увеличивается.

При нажатии верхней кнопки угол тангажа увеличивается, а скорость вращения уменьшается.
По рысканью, наоборот, при нажатии правой кнопки, угол уменьшается, а скорость увеличивается.
По крену опять наоборот. Угол увеличивается, а скорость уменьшается.

Я не понимаю логики разработчиков.

Мне тоже удалось состыковаться с первого раза, но только благодаря тому, что симуляция не реалистична. Если добиться, чтобы отклонения по углам стали нулевыми ни не менялись в течение нескольких секунд (угловые скорости при этом могут остаться не нулевыми), то они так и остаются нулевыми. На них можно вообще не смотреть.