Tag Archives: orbiter

This material can heat to 2200 F, but it’s safe to hold in your bare hands

 

Designing an orbiter that is able to endure the brutal -250 F in the outer stretches of space, as well as the bewildering 3000 F during the reentry is a ridiculously challenging task.

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Space shuttle is the name for the entire setup, whereas the orbiter is the ‘planeattached

The Thermal Armor

Ergo, after churning the minds of the elite scientists and engineers, we now have the TPS (thermal protection system) that protects the orbiter from this harsh temperature difference.

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The thermal protection system is like an armor that maintains the outer skin of the orbiter within acceptable temperatures. This is achieved by employing various materials on the outer structural skin.

Wait, what kind of materials?

The tile’s material is an insulator. These materials do not exchange heat easily.

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Cardboard, being an insulator protects your hand from the hot coffee. (PC: Nirzar)

Conductors on the other hand are the exact opposite. They love to give away their heat.

This is the reason why touching a hot aluminum / stainless steel ( Conductors ) pan at a moderate 100 C would cause burns, but touching the Space shuttle tile (An amazing insulator) at 2200 C is probably not a bad idea!

 

Let’s cut to the chase: What are they?

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A used tile from Atlantis

Those small white cubes are LI-900. It is a type of low-density insulating material which is composed almost entirely of silica glass fibers.

Purest quartz sand with 94% air by volume constitutes the LI-900.

 

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It’s sort of like foam/ a sponge, if you think about the huge amount of air that it contains.

And also, Air and silica are both extremely poor conductors of heat and thus great insulators.

As is evident from the animation provided above, they can be heated to 2200°F, and even after being subjected to that temperature can be picked up almost immediately.

Surprisingly, these tiles are not mechanically attached to the aircraft, but instead glued. And many of them are replaced after each flight.ShuttleTPS2-colored

White tiles (known as LRSI) were used mainly on the upper surface and have higher thermal reflectivity. These are therefore pointed towards the sun in order to minimize solar gain.

Black tiles (known as HRSI) are optimized for maximum emissivity, which means they lose heat faster than white tiles. This property is required in order to maximise heat rejection during re-entry.

Screwing up the TPS is a recipe for disaster

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Due to a damaged heat shield, the space shuttle Columbia disintegrated upon reentry in 2003, killing all crew members. Designing such an integral component of the space shuttle requires utmost meticulousness.

Perceiving Temperature

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When something feels hot to you, it’s really because there is a large amount of heat transferred between the object and your skin.

And when there is very less heat transfer, we perceive it as cold!

In the case of the space tile, since it’s a good insulator it is conducting (transferring) energy at a remarkably low rate.

Ergo, if we were to touch it, it will fell the same as a quotidian household object.

Cool eh ?

NASA fuels Endeavour for one last round

As I was telling you a few days ago, after Discovery, Endeavour is also preparing for its last trip, led by space veteran Mark Kelly. The weird thing is that Endeavour, which will be retired after today’s last mission, is at the moment also NASA‘s youngest orbiter, which kind of speaks a lot about NASA’s capacity to modernize its fleet. The thunderstorm that took place last night provided some spectacular photos, but it probably won’t affect the launch in any way.

space shuttle Endeavour

Endeavour is set for launch today, April 29, at 3:47 p.m. EDT (1947 GMT) from the Kennedy space center, in what seems to be like good weather. However, if clouds or some other meteorological problem is present, the launch will be delayed, but not too much.


Endeavour space shuttle

The orbiter will travel to the International Space Station (ISS) for a two week visit. Its goal is to deliver a $2 billion astrophysics experiment designed to hunt for exotic subatomic particles.

The shuttle’s whole crew consists of six veterans, including pilot Gregory H. Johnson and mission specialists Michael Fincke, Greg Chamitoff, Andrew Feustel, and European Space Agency astronaut Roberto Vittori, will be led by commander Mark Kelly.

Endeavour’s launch has drawn an impressive amount of public to the site, and all in all 700.000 people are expected to watch the launch – even though it’s scheduled on the same day as the big royal wedding between between Prince William and Kate Middleton in England. President Barack Obama, his wife Michele, and his two daughters will also be present at the launch; it is only the second time in history that a president will be present at a shuttle launch, after Bill Clinton’s visit in 1998.

Another high profile visitor will be Kelly’s wife, wounded Congresswoman Gabrielle Giffords, who was tragically wounded after a failed assasination attempt when a gunman opened fire on her and others outside a Tucson, Ariz., grocery store. This was tragic not only for Kelly, but for the whole crew, who always sticks together:

“The crew has just done a tremendous job of staying on focus and being trained and ready to go fly,” NASA’s associate administrator for space operations, Bill Gerstenmaier, said during a press conference last week. “It’s a testimony to the entire crew’s ability to stay focused, to compartmentalize and to do what they need to do.”

The Alpha Magnetic Spectrometer (the astrophysics experiment I was telling you about) will be installed on the space station with the goal of keeping an eye out for cosmic ray particles that might shed light on cosmic mysteries such as the invisible dark matter which has puzzled researchers for so long.

“It’s the premier physics experiment; it’s probably the most expensive thing ever flown by the space shuttle,” Kelly said in a NASA interview.

In addition to the spectrometer, Endeavour will also be carrying 14,000 pounds (6,350 kg) of spare supplies to outfit the space station for the era after the shuttles stop flying. To help install some of the equipment, an ambitious four space walks are scheduled, which will be finished in 14 days, but NASA says they are fine with a few extra days as well. Even if everything goes according to plan, the victory will be bittersweet at best, because this doesn’t only mark the end of Endeavour, but it marks the end of an era.

“We know the end is coming and we’re dealing with it,” shuttle launch director Mike Leinbach said. “The emotional aspect is very, very real and it’s very difficult to put into words, but I think all of Kennedy Space Center got a big boost when we got the word that were going to be able to keep Atlantis.”

After Endeavour’s last flight, NASA plans one more shuttle flight, the June launch of Atlantis, and after that, the space shuttle program will come to an end. That’s it, no more Discovery, no more Endeavour, no more Atlantis; no more space orbiters for NASA. I don’t know about you, but it’s pretty emotional where I’m standing.

Space ships retirement place announced, Houston snubbed

Everybody was eager to see where the four space ships who will soon be retired will go; the idea was to chose a museum which somehow has connections with the space program, and where a lot of people can see it. Well, what city has more connections with the space program than Houston ? It seems like a no-brainer. But this wasn’t the case, unfortunately for them, because NASA thought otherwise.

They chose Washington, D.C., New York City, Los Angeles and the Kennedy Space Center in Florida, argueing that these are the places where the most people could see them. It came off quite as a surprise, especially to backers of the Houston bid.

“We are really disheartened,” said Richard Allen, president of Space Center Houston. “I don’t think the decision was based on the merits. Houston has a long association with the space shuttle program, of course. All flights were led out of Mission Control at Johnson Space Center, and astronauts who flew aboard the shuttles lived and trained in the community.”

Snubbing the heart of the space program to include the biggest and richest cities, that’s … well, something you would expect from NASA, lately. Even though I’m not connected with Houston in any way, I do believe it was only honest for them to get one of the shuttles, even though they aren’t the biggest city in the race. I think they deserved it, and this came out like a punch to the gut.

“We’re the ones who came up with the concept,” said George Abbey, a former director of Johnson Space Center from 1996 to 2001 who is now at Rice University’s Baker Institute for Public Policy. “We designed it. We tested it. We operated it. Certainly Houston ought to be number one on the list. Houston wasn’t in the top four.”

It’s my opinion that the decision was also a political one, in which Texas lost, due to the current leaders of the White House and Congres, but NASA strongly denies this.

“I have felt no political pressure at all during this process. I’m apolitical. I’m here to do what is best for NASA,” said Dominguez, assistant administrator for NASA’s Office of Strategic Infrastructure.

But doing what’s best for NASA… that’s a statement that leaves room for interpretation. Either way, the Smithsonian was always going to get a shuttle, that’s easy to see for everybody. Shuttles are launched from Kennedy Space Center, so that makes a good argument too. But for the other ones, things aren’t so clear. They were involved in the space program, just not as much. Anyway, what’s important now is that the space ships are going to be put for display in the cities I told you about, and it would be a crying shame not to go see them if you get the chance.

Endeavour launch delayed due to Russian schedule

Endeavour was set to take of in a really short time, and everybody was ready for this, but in an attempt to avoid a scheduling conflict with a Russian supply ship headed for the International Space Station (ISS), the launch of Endeavour has been delayed until April 29. The Russian spaceship will be launched on April 27 and will reach the ISS two days later, on April 29.

Endeavour was set to go less than three weeks from now, on April 19, but NASA was forced to delay the launch due to these events. There have also been some fears expressed regarding the recent violent storms that hit Florida’s Kennedy Space Center on Wednesday and Thursday. Officials found “only minor damage” and “evaluations indicate there was no damage to the spacecraft,” NASA said.

The mission will be the last one for Endeavour, which will be retired, just as fellow orbiter Discovery, which went on its last mission this year. It will be led by Commander Mark Kelly, whos brother is also an astronaut and returned only recently from the ISS – imagine the dinner conversations around that table.

Amazing picture shows Endeavour waiting for its last mission

While aimlessly browsing the Internet, I found this amazing picture, showing Endeavour patiently awaiting its last mission before a well deserved retirement. After Discovery, Endeavour is the second legendary orbiter to be put in a museum. For NASA, it’s the end of an era – we’ll see how it goes from here.

Photo by NASA.

 

Space Shuttle Discovery heads home after final mission

When launched in 1984, Discovery was top notch; it was the best available around, and only the third operational orbiter; now, after 3 flights, over five thousand orbits and no less than 365 days spent in space, during which it traveled 150 million miles Discovery left the International Space Station (ISS) for the last time; it is still, for a few days, the oldest orbiter still working. It was a sentimental moment for many people, and station skipper Scott Kelly rang his ship’s bell in true naval tradition, paying tribute to the shuttle after its last departure.

“Discovery departing,” he called out.

Discovery is due to Earth on Wednesday, after which it wil be retired and sent to the Smithsonian Institution for display. Discovery’s astronauts got a special greeting from actor William Shatner, who portrayed captain James Kirk on the original “Star Trek” TV series.

ZME Science would like to take a bow and pay homage to Discovery, and thank all the people who were involved in any way in it’s remarkable achievements !

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