OSIRIS-Rex: Dinosaur or science mission?

On September 8th, 2016, NASA used an Atlas V (411) ¹ to launch the OSIRIS-REx ² asteroid sample return mission ³ to asteroid Bennu⁴.

So let's review what that means:

1) The Atlas V (411) is a two-staged rocket built and operated by United Launch Alliance that has been in service since 2002, primarily used for launching military satellites and often sending robotic probes to far-off solar system destinations. As launchers go the Atlas V has an incredible reliability record with 65 straight successful launches. There have been a few minor in-flight issues here and there but the "Mighty Atlas" (as ULA's CEO is fond of calling it) always gets the job done. As successful a rocket as it may be, it's not been without controversy. In fact, in the wake of Russia's incursion into Crimea the US government temporarily banned the import of Atlas V's first stage engine because it is built in Russia.

     Atlas V comes in several variants, which is the reason for the "411" code in this instance. That means that it has:

• A 4-meter diameter (13.1 ft) payload fairing that protects the payload during flight through the atmosphere. A 5-meter (16.4 ft) fairing is also available for larger satellites.
• 1 side-mounted Solid Rocket Booster, built by Aerojet Rocketdyne, to provide additional thrust early in the flight. Atlas V can use up to five SRBs.
• 1 Centaur upper-stage engine to take the payload from the upper atmosphere to its final orbit. This upper-stage can have one or two engines.

 Below you can watch the launch of an Atlas V 551, one of the most powerful variants.

For more information, check out ULA's website.

2) OSIRIS-REx is unfortunately NOT a dinosaur but a NASA mission with perhaps the most cumbersome acronym of all time. Its full name is the Origins Spectral Interpretation Resource Identification Security - Regolith Explorer. The mission is designed to visit an asteroid (Bennu) that occasionally passes close to the Earth, to study and characterize it. OSIRIS-REx will

• Measure how sunlight absorbed then re-radiated by the asteroid's surface causes it to rotate and change its orbit around the sun over time--called the Yarkovsky Effect. This could affect how close Bennu comes to Earth--possibly close enough to impact our planet in the future.
• Map the distribution and chemistry of Bennu's surface.
• Return a sample of the asteroids loose rocky, dusty surface material called "regolith." More about this in the section below.

 

3) Asteroid sample return is OSIRIS-REx's primary mission. After orbiting Bennu for an extended time to understand its gravity and rotation, an arm will extend to the surface and release a burst of gas to push surface material into a surrounding screen where 2 to 70 ounces (60 to 2000g) of the material will be captured. That capture device (called TAGSAM) will then be encased in a heat shield and make a fiery return to Earth's surface. This will allow the samples to be handled and analyzed by scientists with a wider range of observational and testing equipment than if mission planners sent a select few instruments into space. It will also allow scientists to save samples for future generations to study with currently-unknown testing processes that may be developed in the decades to come.

4) Asteroid Bennu is a 1,600 ft (500m) wide asteroid and, like all asteroids, is a remnant of the formation of our early solar system. After gravity had gathered most of the material into planets and moons what was left over became the asteroid belt. Radar and visual observations lead scientists to believe that Bennu is extremely high in carbon which also gives it a remarkably low level of reflectivity. This has made observations difficult but OSIRIS-REx's visit will provide first-ever close up imagery and radar data on this asteroid. That data will be compared with Earth-based observation that may reveal better observation methods for the future that could come in handy nearing the years 2175 to 2196 when Bennu stands a 1-in-2700 chance of impacting the Earth. Looks like humans of the future could either use good luck OR good science.


Have you somehow reached the end of this and have a desire to read MORE detailed information about the OSIRIS-REx mission? Well you can click this link for the official mission factsheet.

 

Sounding Rockets

On August 17th, 2016, NASA's Wallops Flight Facility launched a suborbital sounding rocket for the RockSat-X mission. Now...what the heck did all of that mean?

Let's break it down.

NASA's Wallops Flight Facility is an airfield and launch complex at Wallops Island, on the eastern shore of Virginia. For over 70 years this facility has conducted orbital and suborbital (see next paragraph) rocket launches for research purposes, has managed scientific balloon projects, conducted flights to the arctic to measure sea ice change, and launched drones to fly through and measure hurricanes. Most recently this facility has gained attention for being the launch site of Orbital ATK's Antares rocket which resupplies the International Space Station.


A suborbital rocket is one that launches into space but no part of that rocket stays there. Everything that goes up comes back down. Orbital rockets fly a path mostly parallel to the Earth's surface, which is how they end up in a circular orbit around the planet but suborbital rockets often fly very steep vertical trajectories. They fly as low as about 30 miles and as high as 900 miles above the Earth's surface then descend back to the surface. The upper sections of the rocket that carry the science payloads are returned to Earth under parachutes where they splash down in the ocean and are recovered by boat crews. Flights often last as little as 15 minutes.

Sounding rockets get their title from maritime tradition. In the old world of sailing ships, to "take a sounding," meant to drop a weight and length of rope into the water to measure the depth beneath your ship. So "sounding" became a synonym for "measurement." Thus, sounding rockets are simply measurement rockets. They carry a wide variety of science experiments into the upper atmosphere and the reaches of space several hundred miles above our heads for the purpose of measuring natural phenomena that only take place there, to make brief observations of astronomical targets, or sometimes to run brief experiments in microgravity while the rocket is in free-fall back to Earth. The variety of subjects to measure and ideas to test is so extensive that NASA's Wallops Flight Facility has conducted over 16,000 sounding rocket flights.

RockSat-X is a cooperative program where several universities conduct their experiments on the same rocket flight--in this case it was a rocket called a Terrier-Improved Malemute. No, this is not a new dog breed mix, it's a combination of a Terrier booster rocket and a Malemute upper stage. (No, I don't know how they got those names) This particular flight included experiments that observed crystal growth in microgravity, observed how a molten blob of metal cools and reshapes in microgravity, tested the strength and effectiveness of 3D printed airfoil shapes, detected and collected micrometeroids, and a set of HD cameras to watch the deployment of all of these experiments and more. RockSat-X reached 95 miles in altitude and many of the experiments returned their data via radio but unfortunately the upper stage with the experiment hardware was not able to be recovered which means that some of the physical experiments could not be examined in person. For more detailed info on this mission just click here.


If you have any questions about what you just read or would like to read more info on anything mentioned here, please leave a comment or contact me!

Progress - The Swiss Army Knife of Spacecraft

Shortly after noon today, a Soyuz rocket blasted away from the Baikonur Cosmodrome in Kazakhstan, carrying a cargo vehicle known as "Progress" to the International Space Station. There are a number of spacecraft resupplying the ISS these days* but Progress is (arguably) the most versatile.

In order to operate a space station you need a number of recurring services:

• Delivery and return of crew members
• Delivery of consumables (food, water, oxygen, fuel)
• Delivery of hardware (station parts, spacesuit parts, science experiments)
• Removal of waste (food packaging, broken hardware, completed experiment hardware)
• Orbit and/or attitude adjustments (rotate orientation, increase or decrease altitude to avoid orbital debris or to compensate for atmospheric drag--yep, at 250 miles there's still enough air to slow it down!)

Progress can handle all of those tasks but one; carrying crew to and from orbit. The reason for this lack of capability is that Progress is a direct descendant of the crewed Soyuz spacecraft, which has been the workhorse of Russian spaceflight in constant operation (and upgrade) since 1967, with great successes**. Rather than develop a completely new vehicle, the Russian space program chose to adapt their proven design into a cargo-only vehicle.

The Progress is composed of three segments: a pressurized cargo module, a refueling module, and an instrumentation/propulsion module.

The forward, somewhat spherical segment is the pressurized cargo area that will contain nearly 4,000 lb. of hardware, food, and some water that the cosmonauts and astronauts will manually remove once this portion of the vehicle docks with the ISS. In the months after this cargo is unloaded, that same area will be filled with the multiple forms of waste that life inevitably generates.

At the center of the spacecraft is the refueling module. As you can see in the diagram, this segment is filled with a number of tanks that contain fuel, oxidizer, and sometimes water. Not all missions require more water to be transported so there is some variation in this segment. Again, this segment could hold nearly 4,000 lb. The fuel can be transferred from Progress to ISS by connections in the docking ring, where the two spacecraft meet, eliminating the need for crew to be exposed to hazardous materials. As far as I know, Progress is currently the only spacecraft capable of this function, making it that much more important to station operations.

In the crewed Soyuz this space is the descent module where the crew's seats and instruments are located. To return to Earth, the forward segment and propulsion segment behind it would detach and a heat shield between descent and propulsion modules would protect the crew during atmospheric reentry. No such shielding is needed for Progress. Remember all that trash to be loaded in the cargo area? It's meant to be burned during atmospheric reentry.

The final segment at the rear of the vehicle not only does the work of navigating Progress to the ISS, it also serves as an instrument of orbital adjustment. While the ISS has it's own on-board engines for attitude and orbit adjustment, it is wiser to use those of the visiting spacecraft because the hardware on the ISS must remain on orbit for years (in the end it will be multiple decades) while the visiting spacecraft is newer and more recently inspected to assure safe and effective operations. This also reduces the need to transfer fuel between vehicles. The Space Shuttle was able to facilitate these orbital adjustments but that system was retired in 2011. The Japanese HTV can also provide reboosts but is an infrequent visitor to ISS, leaving the Russian Soyuz and Progress to do much of the work.

So as you can see, Progress really serves as many vehicles. It is the delivery truck, it is the fuel tanker, it is the tow truck, and it is the garbage truck for the International Space Station. It's not glamorous work but it all has to be handled. With all of these support tasks taken care of, the crew can get down to their true purpose on orbit: scientific experiments that, in one way or another, will advance the knowledge and abilities of humanity as a whole. So I suppose you could say that ISS needs Progress to enable progress.

Has there ever been a more appropriately named vehicle?

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*Current: Progress (Russia), Dragon (USA), Cygnus (USA), H-II Transfer Vehicle (Japan)
  Retired: Space Shuttle (USA), Automated Transfer Vehicle (Europe)
  Future:  Dream Chaser (USA)

**Of course, Soyuz has also had its set of failures. But that's a matter for another time.

NASA? Didn't they shut down a few years ago?

Despite my persistent (annoying?) posting and sharing efforts, I've been getting the impression that the general public is still in the dark regarding the ongoing efforts of my most favorite US-based, government-operated aeronautical and spaceflight focused agency. I speak, of course, about NASA! Yes, the space shuttle people. The people who, after retiring the shuttles, didn't just pack up and go home. They have moved on to some amazing and exciting developments. Sadly though, when I recently surveyed the people around me to find out what they knew about NASA’s current mission, the results were a bit disappointing. In fact, the results can be summarized as, “No idea!” *Sigh* Well there's only one thing to do. It's back to square one.

Below is the "big picture," which will be the basis for all my upcoming entries. If you learn and understand this, you're already ahead of most people. As the days go on, I'll be putting up entries that will detail each of these projects and show you what the heck they're good for because, sadly, some people think we're wasting our time, effort, and money with this crazy spaceflight business. (Those people should learn that every dollar invested in NASA yields approx. $10 in US economic benefit!)
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NASA’s current vision can be split into two primary categories: manned and unmanned missions. 

·         Unmanned missions: space telescopes, rovers, landers, or orbiting probes that are studying the planets, comets, asteroids, stars and galaxies in very specialized ways with very specialized instruments. These studies will give us a better understanding of how our entire universe came to exist and our place within it.

·          

     The manned missions can be further split into two categories:

o   Low Earth orbit: within a few hundred miles of Earth. This means our orbiting science laboratory, the International Space Station. Here we perform lots of science that can only be accomplished in orbit where there is nearly no effect of gravity. The bulk of this research is in materials science and human biology under long-term effects of microgravity.
   In days of old, this was serviced primarily by the Space Shuttle. The shuttles were retired in 2011 and now NASA contracts commercial companies (SpaceX and Orbital Sciences) to send resupply spaceships to the ISS. Within the next few years they will also begin commercially operated transportation of astronauts to the station. (Boeing CST-100 and SpaceX Dragon v2)

These operations are much more economical than the shuttle, allowing NASA to focus more of their budget developing spacecraft for…

o   Beyond Earth orbit. NASA is developing a new capsule (Orion) and new rocket (SLS) that will allow us to travel for months, possibly even years, away from our safe and comfortable home world. Plans are most likely to ignore the moon (for now), and initially try to intercept asteroids, allowing us to develop new techniques for living and operating on long-term missions as well as studying those big stone solar system left-overs. Ultimately, the goal is humans on Mars. A trip to the Red Planet will be a minimum of 9 months. Each way. So the goal is to develop self-sustaining systems that will allow us to travel safely, live comfortably and in good health, and begin inhabiting a second planet in our solar system.

 So that's the BIG picture. In the coming days I'll add detail to each segment of NASA's space operations and hopefully give everyone a better understanding of what's in store for the future. Got questions? Feel free to leave 'em in the comments section below.

My Journey to NASA Wallops - Part 1: Excitement and Frustration

On December 4th of 2013, I received the most exciting e-mail that has yet to grace my inbox. It was from NASA Social, a small crew that coordinates the social media efforts of NASA as a whole and organizes special events. The e-mail was to inform me that my application had been accepted for media credentials to attend their next event: the launch of the Orbital Sciences Antares rocket with Cygnus resupply ship, departing from Wallops Flight Facility in Virginia, destined for the International Space Station. After a lifetime of obsession with spaceflight I was finally going to see a full-scale launch in person! As a bonus, it turned out that the launch date was December 17th, exactly 110 years to the day that the Wright Brothers first flew.

I confirmed my intention to attend, I booked a hotel room, I took off from work. All that was left was the awful wait. Knowing that I was attending made the next few days crawl like molasses and the two weeks until launch say seemed a torturous wait.

December 9th - I got an e-mail stating that the launch had slipped back a day, to the 18th. Not a big deal. It's spaceflight and these things happen. The hotel happily changed my reservation and my work was kind enough to change my days off. The schedule of events arrived not long after and this particular rocket nerd was overjoyed seeing the specifics of what was in store for me.

I was so glad we got that delay out of the way early. The Antares is a reasonably simple rocket and they'd reported that they were working no issues and there was a 95% chance of favorable weather. "Let's do this!" I thought.

December 11th - The International Space Station experienced a major malfunction of the ammonia Cooling Loop A, causing heating issues onboard. The crew was fine but a number of systems aboard ISS had been shut down to preserve power for sensitive experiments. If the issue wasn't resolved soon it would have an impact on launch date because there is an added level of risk anytime two spacecraft dock together but to do so with one spacecraft (the station) in a deficient state would be unnecessarily dangerous.

December 14th - Planners/controllers at NASA decided to delay the launch until December 19th while the ISS ground controllers attempted to regulate the temperature control system through a software modification. So far the software changes had limited success and they were attempting to find a "sweet spot" that would allow the Antares to fly up and dock with the ISS on time, then astronauts could conduct spacewalks to replace the malfunctioning flow valve. NASA was going ahead and loading time-sensitive cargo into Cygnus in case it all worked out. I called the hotel to push my reservation back another day. The woman on the phone asks why I needed to change and when I tell her about the launch delay she say, "Oh, we're going to get a LOT of that today!"

December 17th - With no word advising otherwise, I began to pack a bag to depart the next morning for my two days down in Virginia. While checking to see what my fellow Social attendees were saying via Facebook and Twitter I stumbled across the NASA announcement that they would indeed be delaying the Antares launch until some time in January. My mind has a tendency, which I sometimes like and sometimes dislike, to easily notice connections between events, such as the fact that this flight was delayed until "some time" on the day that I originally thought I would see that rocket climb to space while hearing and feeling the roar of those AJ-26 rocket engines... Stupid brain. Why would you go and point out something like that when you know I'm already annoyed?

December 20th - It was announced that the launch had been reschedule for NET (No Earlier Than) January 7th, 2014. Again, the requisite plans were assembled. Took a couple more days off from work and booked a hotel room again. One cool aspect of all this was that the woman at the hotel gave me the room for the same rate that I had in December "because you're with the NASA group." It is pretty awesome to have somebody say you got something because you're "with" NASA!

In the coming days we learned that the software patch for the ISS ammonia flow control valve wasn't working and after a series of very successful spacewalks the malfunctioning components were swapped out for functional ones. With this, the problem was resolved and the station was once again ready to receive a visitor, in the form of a Cygnus resupply spacecraft.

And then we all got to learn an evil new phrase:  

"Polar Vortex"

I don't know the technical details behind it (I'm more interested in things that fly through the atmosphere than the actual atmosphere itself) but I've come to believe that it's when that guy Snow Miser from "The Year Without A Santa" beats his brother Heat Miser in a boxing match and everywhere gets to measure local temperature with single digits. Both Fahrenheit and Celsius.

On January 3rd, the launch was delayed another day, until January 8th, because the air temperature dropped below the operating temperature of some of Antares' components.

What did I do to deserve such torment from the universe?!

Thankfully, no further delays occurred and in the early hours of January 7th I left home on an exciting journey to see things in person that I had heretofore only seen in pictures or read about.

To be continued in My Journey to Wallops - Part 2: My Dream Day

Catching up with a 17,500 mph Space Station

When the Antares rocket took off from NASA's Wallops Flight Facility in Virginia this past Thursday, its Cygnus payload didn't go straight to the International Space Station. The fact is that very few vehicles destined for the ISS go straight from launch to the station. A typical trip to the station is a multi-day voyage and it's only been in the past year that manned flights have begun taking an expedited path and timing that can get crews there within 6 hours of launch.

To understand why we don't usually go from ground to station in one quick trip there is a key concept to know first: in orbit, speed equals altitude. 

The basic concept of an orbit is that an object is moving parallel to the surface of the Earth. Gravity is still pulling on that object so it's in a constant state of "falling", but the object is moving so quickly that by the time it reaches the horizon the surface of the planet has curved down and away from the object. So if that object, such as a Cygnus capsule, keeps going fast enough it will "fall" indefinitely and remain in orbit around the planet!

Hopefully this terrible illustration above helps to visualize the concept. As a projectile (the black circle) moves faster it travels farther along the horizon before finally falling to the ground (the black line).

This second terrible illustration shows that with enough speed the projectile would move forward and downward at the same rate as the surface of the planet, creating an orbit. Because of this concept we have to operate differently in space when trying to go "up", or away from the planet. A spacecraft can't just point away from the planet and fire its engine because it would actually slow down. What it needs to do is fire its engine in the direction of travel! If it goes faster it won't just move parallel to the horizon but actually overshoot the path of the ground. Hm...this may seem confusing. Perhaps its time for yet another awful illustration?

On the left side we see an object orbiting a blue planet. To get that object farther from the planet it fires its engines, pushing it in the direction of the arrow. Eventually it moves so quickly that its path (the red curved line) gets wider than it was before and it moves outward to the second orbit seen on the right side of the diagram.

Now that you have this concept in mind I can tell you that the reason why a vehicle doesn't usually go directly to its destination orbit is because a higher orbit means a faster orbit and a faster orbit means a bigger rocket to give it the "get up and go." Bigger rockets are more complex, heavier, and more expensive so their use is a potential hindrance to regular and affordable launches. But wait! Science to the rescue! Once the vehicle is in orbit it has shed the weight of the rocket that carried it there and its in a vacuum so there's no air resistance. This means a rocket motor is MUCH more efficient in space than in our atmosphere, allowing the Cygnus, in this case, to use its own on-board rocket motor to fire several times and incrementally increase its orbit, which during the ongoing Orb-1 mission calls for 5 "Delta V" (change in velocity) burns that take the vehicle from its original orbit of 134 miles to 226 miles. This stops Cygnus four miles beneath the space station where it then makes a slow, controlled approach. That approach occurred this morning (Jan 12) around 6:00 am EST and by 8:00 am the astronauts aboard the station used the Canadarm 2 robotic arm to grapple and reposition the vehicle for final docking.

Antares, International Rocket for an International Station

One of the two rockets being put to use these days in resupplying the International Space Station is the Orbital Sciences Antares, named for a star in the constellation Scorpius. Antares is a two-stage rocket intended to carry the Cygnus resupply vehicle (a more detailed post can be written about that if there's interest).

Antares is a multinational project, assembled from components built in 4 different countries on 3 continents, which is incredibly appropriate for a vehicle intended to resupply an international scientific outpost. So let's check out the parts from the bottom up:


 AJ-26 Rocket Engines - The part that really makes the thing get up and go! Antares has two of them and when they were originally built they were called NK-33's. These engines have a pretty interesting history because they were built in the late 1960s. 
By the Kuznetsov Design Bureau. 
In the Soviet Union. 
For the N1...their MOON ROCKET!

That rocket was unsuccessful overall but these engines were so advanced at the time that they're still up to modern performance standards with some relatively minor upgrades from the Aerojet Rocketdyne company in California, who has a large enough stock of those motors to supply the Antares for all eight contracted flights to the ISS with some to spare. Antares has two engines that are gimballed, meaning they're mounted in a way that they can be tilted to steer the rocket.

First Stage Fuel Tanks & Structure - The bulk of the rocket is made up of this first stage structure that contains a fuel tank for liquid oxygen (takes up about 2/3 of the length) and a fuel tank for RP-1, a modified form of kerosene. There are also helium tanks built into the fuel tanks that are used to force the oxygen and kerosene out of their tanks and into the engine as quickly as possible. This major section is designed and built by Yuzhnoye Design Bureau in the Ukraine, based in large part on the Russian Zenit rocket.

Interstage Assembly - This is the section that connects the first stage to the second and helps keep the rocket on the right course as it gets close to orbit by operating thrusters, small rockets used to control direction, as the rocket cruises between stages. Built largely from US-based Orbital Sciences' flight computers used on the Pegasus air-launched rocket, this hardware is considered exceptionally reliable which is great because if the rocket can't stay on course then there's no point in launching at all.

CASTOR® 30B Second Stage Motor - Unlike the first stage motors, the second stage is a solid-fueled motor built by Alliant Techsystems (ATK), a manufacturer from Utah that also built the Solid Rocket Boosters for the Space Shuttle. At a recent tour of NASA's Wallops Flight Facility a representative of ATK stated that the fuel formula they're using for Antares is a drastically better than the shuttle fuel which was designed in the 1970s.

Cygnus - The only part of the entire launch that will make it to orbit is this capsule-type spacecraft. It's made of two sections, the Pressurized Cargo Module (PCM) and the Service Module (SM). The SM is the "brains" of the vehicle, containing the solar panels, the rocket engine and thrusters, communications systems, and the environmental controls for inside the PCM, which is where the supplies and hardware meant for the station are stowed away. The SM is based largely on satellite hardware developed and built by Orbital Sciences in the United States. The PCM, on the other hand, was developed and built by Thales Alenia of Turin, Italy, sharing its design heritage with many sections of the space station and the Automated Transfer Vehicle (ATV) built by the European Space Agency.

 All those pieces from all those countries come together at the Horizontal Integration Facility at NASA's Wallops Flight Facility where they become the Antares rocket, one of America's newest launch options that is making low-Earth-orbit resupply an economic and routine process.

I hope you enjoyed this explanation of the Antares rocket and if you have any questions, comments, or suggestions then go ahead and leave a comment below! As always, thanks for reading!