Northrop Grumman’s Cygnus Space Freighter Departs Space Station

From NASA

Northrop Grumman’s Cygnus space freighter departs the International Space Station moments after being released from the Canadarm2 robotic arm on Thursday, Jan. 7, 2021, completing a 93-day cargo mission attached to the orbiting lab.

The Cygnus spacecraft successfully departed the International Space Station three months after arriving at the space station to deliver about 8,000 pounds of scientific experiments and supplies to the orbiting laboratory.

Prior to departure, the crew packed Cygnus with the Saffire V investigation and the SharkSat hosted payload to be conducted during an extended mission in orbit. On Jan. 26, Northrop Grumman flight controllers in Dulles, Virginia, will initiate Cygnus’ deorbit to perform a safe re-entry, burning up in Earth’s atmosphere.

Image Credit: NASA Last Updated: Jan. 8, 2021

Editor: Yvette Smith

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Joseph Zorzin
January 11, 2021 4:05 am
Right-Handed Shark
Reply to  Joseph Zorzin
January 11, 2021 5:03 am

Sorry, couldn’t get past the first paragraph, so sycophantic it made me feel physically sick.

Joseph Zorzin
Reply to  Right-Handed Shark
January 11, 2021 7:20 am

I agree but I think it’s good to “know your enemy”.

Shark24
January 11, 2021 5:55 am

I find it amazing that NASA still pays to have a delivery system that burns up upon reentry when SpaceX is providing reusable capsules. Northrop and Boeing are playing catch up.

MarkW
Reply to  Shark24
January 11, 2021 7:01 am

It’s little more than a tin can with a guidance system.
Building them to survive re-entry increases cost, weight and reduces how much cargo it can carry.

Joel O'Bryan
Reply to  MarkW
January 11, 2021 7:43 am

Agree. We live in a disposable society. I drink a soda and toss the can or bottle away. Very few actually get recycled. In days gone by, glass soda and milk bottles used to go back for re-use but material costs now are low compared to the water and expense of washing and inspecting every single one. And then the old horror stories for the companies of a customer finding a dead mouse in their soda. Litigation risks preclude direct re-use of many thing sin the consumer market.

The cost of refurb on a space vehicle that has gone though re-entry heating and ablation and then a salt water immersion simply isn’t worth the risk of a relaunch carrying valuable cargo back up to the ISS. The cargo going up to the station can cost way, way more than the vehicle, so why risk a re-using a cooked and salted old one?

Last edited 6 months ago by joelobryan
Shark24
Reply to  Joel O'Bryan
January 11, 2021 11:29 am

But the Dragon is carrying back experimental data. Is that a consideration?

MarkW
Reply to  Shark24
January 11, 2021 12:04 pm

Not every returning craft needs to carry back experimental data.

Kpar
Reply to  Joel O'Bryan
January 12, 2021 8:43 am

Indeed. Besides, is it necessary to recover all that poop? I’d hate to be the guy who had to unload the landed capsule. There are some advantages to “burning stuff up” on re-entry.

Stargazer
Reply to  Shark24
January 11, 2021 7:51 am

It is carrying space station garbage intended to be incinerated.

snopercod
Reply to  Stargazer
January 12, 2021 4:05 am

Soiled diapers, most likely.

DonM
Reply to  Shark24
January 11, 2021 12:49 pm

don’t get too carried with the concern.

if the UN will proposed and moved towards enacting a deposit on anything that gets more than 100 miles from the earth … like a bottle deposit … biden & his handlers might jump on board the concept.

January 11, 2021 6:12 am

I hope the right person will discuss here being able to answer my question.
I know and it’s clear, when re-entering the atmosphere, a heat-shield is needed.
For what reason, when leaving the atmosphere, it isn’t needed, as the same layers with different temperatures are traversed ?

Last edited 6 months ago by Krishna Gans
Archer
Reply to  Krishna Gans
January 11, 2021 7:00 am

Speed and shape.

Going up, the rocket is aerodynamically shaped to minimise friction and gets through the majority of the atmosphere before it reaches a speed capable of causing significant friction heating. The majority of its acceleration takes place above the majority of the atmosphere.

Going down, the capsule has a larger, flatter profile and is travelling at much higher velocity when it reaches the relatively thick mid and lower atmosphere. Much of the heating it encounters is also due to compression rather than friction.

Kpar
Reply to  Archer
January 12, 2021 8:51 am

Right you are. Velocity and air pressure are the key.

MarkW
Reply to  Krishna Gans
January 11, 2021 7:05 am

As I understand it, the difference is caused primarily by two factors.
First, When launching the sharp, pointy end of the spacecraft is facing forward, allowing the spacecraft to punch through the atmosphere more easily. When returning, the blunt end is facing forward.
The second has to do with the speed the craft is travelling as it passes through the various layers. On launch, it is travelling much slower while it’s traversing the thicker layers of the atmosphere.

Reply to  Krishna Gans
January 11, 2021 7:16 am

Thanks to both, so I have at least an imginatio of the respective reasons !

Joel O'Bryan
Reply to  Krishna Gans
January 11, 2021 8:02 am

It’s a delta-V problem.
Going up, copious amounts of sustained propellant burn at 2,500ºF out a rocket nozzle cone provides the delta-V to achieve orbital velocity, starting slow where the armosphere is thickest and only getting high mach in the thinnest part above 100,000 feet alleviates the heating going up. There is the max-Q problem to shape the propellant/aceleration problem for the first 90 seconds, that’s why most ascent stages throttle up passing max-Q (Q is aerodynamic pressure on the vehicle).

Coming back to a planet with an atmosphere, the vehicle doesn’t have the same propellant available to provide the full deceleration delta V before hitting the friction wall. So simply use a little bit of thrust to start the de-orbit and let frictional heating from the air do the rest of the delta-V problem.

If a futuristic space craft, like in the scifi movies, with a sufficient sustained high thrust you could slow the vehicle down in the vacuum of space and use nothing but decelerating thrust to avoid atmospheric heating and high pressures on the frontal surfaces. Landing on the moon without an atmosphere to provide deceleration, rocket engine thrust is the only way to slow down to get a soft landing.

Reply to  Joel O'Bryan
January 11, 2021 10:25 am

Thx too, was also helpfull !

Last edited 6 months ago by Krishna Gans
Tom Abbott
January 11, 2021 7:57 am

There’s going to be so much going on in the Earth/Moon system in the next twenty years! I love it! Private enterprise doing its thing in space! Innovating, cutting costs, and getting us there! What’s not to like!

I think Chicom astronauts should be banned from flying on U.S. spacecraft. I hear Biden might want to do some space cooperation with the Chicoms. It won’t be cooperation, it will be blatant theft of intellectual property, and will make the Chicoms even more of a military threat to the world.

The Chicoms should also have to pay for all the losses other nations have suffered because of the deliberate release of the Wuhan virus on the people of the world by the Chicom leader, Xi.

After they pay us back, maybe we’ll give them a ride to space. But that’s all. Thieves not allowed! 🙂

Joel O'Bryan
Reply to  Tom Abbott
January 11, 2021 8:58 am

Do we ban them from our universities? Chinese students and post-Doc fellows are big cash machines for many top engineering universities, not just in the US but Europe and Australia.

The US govt has regulary prosecuted Chinese-American professors sending restricted technology back to China. It is a serious problem, but don’t know what the answer is. Many Chinese students/post-Docs/Profs simply flee back to China to stay if they think the US FBI on to them if they are sending restricted tech back to China.

Tom Abbott
Reply to  Joel O'Bryan
January 11, 2021 12:08 pm

“Do we ban them from our universities?”

I think we should.

What are there, about 300,00 Chinese students going to American universities? They are taking the places of 300,000 American-born students.

America First!, I say.

No offense meant to innocent Chinese, but in the current situation, considering who is governing you, you have to be considered guilty until proven innocent. I’m not against giving you the chance to prove yourself innocent/harmless, but you’ve got it to do, as far as I’m concerned.

Of course, all that doesn’t mean a thing, since I’m not in charge and those that are in charge are the ones who set this system up in the first place so I don’t expect big changes.

On the American side, the Money is what rules the day. The Chinese have the money, so they get the college slots.

They won’t have to fire a shot to defeat us, they will just undermine us from within. Along with the important help of a lot of Domestic Enemies. They are quite far along down this path while the West is just now starting to wake up out of their sleep.

Those who love their personal freedoms have a big job in front of them. Not an impossible job, but a big job, because there are powerful forces arrayed against personal freedom right now.

We have lots of avenues to explore in our quest to retain our freedoms, but the big one is to retain our freedom of speech. Freedom of speech is the first thing the dictators take from the people.

And what is the first thing the radical Democrats are trying to do as they take power? They are trying to restrict the speech they don’t like. If you don’t agree with them, they want to shut you up by any means possible.

Right now, we still have the freedom to speak. Let’s keep it that way. Now and forever.

Kpar
Reply to  Tom Abbott
January 12, 2021 9:00 am

One more thing to remember- ALL Chinese citizens who come to the USA are REQUIRED to report anything the CCP tells them to report. Built-in spies, whether that is their intent or not.

Darrin Burgess
Reply to  Joel O'Bryan
January 12, 2021 10:18 am

Yes we do ban them, It’s a growing scandal that news outlets are ignoring. Uni students are practicing industrial espionage for the Chinese government while in school. As interns they steal from whatever company they are interning at. If they happen to land a job in the US after graduation that espionage will of course continue. Lets not forget they are also networking with other students which turn into another source of unwitting information for the Chinese.

Philip
January 11, 2021 8:43 am

That’s so cool. Too bad the freighter wasn’t reusable. Seems like an expensive waste of materiel to me.

MarkW
Reply to  Philip
January 11, 2021 8:55 am

It’s less expensive than adding and lifting the material needed to let the craft survive re-entry.

Philip
Reply to  MarkW
January 11, 2021 9:32 am

I think the idea that that is less expensive comes from government. I doubt private business will find it so, and will want to invest a little more into something reusable and in more frequent use to get back their investment. Government never seems to worry about getting a return on taxpayer investment.

MarkW
Reply to  Philip
January 11, 2021 12:07 pm

The idea comes from engineer who crunch the actual numbers.
The private sector throws out stuff all the time. Just because something can be reused is not evidence that it is cost effective to do so.

Philip
Reply to  MarkW
January 11, 2021 12:59 pm

Though it is hard to argue that in the short term wasting resources is cost effective. It’s a shame that in this day and age we’re not looking any further in terms of tomorrow than down at our feet.

MarkW
Reply to  Philip
January 11, 2021 2:56 pm

What wasting of resources?

If you want to argue that we should waste resources in order to solve a problem that doesn’t exist then you should be all for solar panels and wind turbines.

Philip
Reply to  MarkW
January 11, 2021 4:33 pm

I can’t make sense of that. Your argument escapes me. Building one offs to supply the space station and have them burn up in reentry is wasteful imho, but it’s more than that too. It’s disappointing from a creative, engineer POV.
Solar and wind arent just wasteful. They’re wasteful because they’re costly and inefficient. No amount of mechanical creativity is ever going to make either good sources of energy production.

MarkW
Reply to  Philip
January 11, 2021 8:36 pm

I fail to see why you fail to see the logic of NASA’s actions.
It’s a matter of economics. It’s very simple, you get much more cargo to the space station is you don’t try to lift a re-entry system along with your vehicle. Less cargo means you must launch more supply missions. As you mention, each launch costs millions, so it makes sense to reduce the number of launches as much as possible. Compared to the cost of a launch, the cost of the capsule is so far below rounding error that nobody who understands economics would care.

Just like wind and solar, putting a re-entry system onto these capsules is both costly and innefficient.

Joel O'Bryan
Reply to  Philip
January 11, 2021 9:02 am

Most people today wouldn’t want to use the glass coke bottle or milk bottle that had been in someone else’s house a month ago. The liability problems for the milk or soda company now are enormous if they tried to re-use bottles. Same for space companies and trying to get insurance on launch vehicles. Why spend a fortune on making a vehicle reusable just to carry garbage back to an Earth soft landing? Frequently the value of the stuff going up to the ISS (experiments, new equipment, computer instruments) is far more vaulable than the vehicle carrying it.

Philip
Reply to  Joel O'Bryan
January 11, 2021 9:42 am

Sounds like a bad excuse to me. I don’t think disposable glass bottles and aluminum cans are any kind of comparable offering to spending millions and using finite resources only to have them burn up in the return to our atmosphere.
Especially if we’re thinking of building a moon station. We will want freighters that are light enough to keep the cost of getting them into space down, but large enough that they carry a workable load (again, the half ton truck for image sake).

MarkW
Reply to  Philip
January 11, 2021 12:09 pm

The millions that are being spent are on the entire rocket. Not just the few percent at the tip.
Even if the capsule was re-usable, the millions spent on the rest of the rocket would still be thrown away.

Making the capsule re-usable would mean you would need more launches because the capsule itself would be much heavier in order to survive re-entry.

Spending millions to save thousands is never a good idea.

Philip
Reply to  MarkW
January 11, 2021 1:04 pm

I didn’t communicate it very well, but my mind was thinking in terms of more reusable components in line with the likes of the space shuttle.
Though a NCC 1701 would be cool. 😁

MarkW
Reply to  Philip
January 11, 2021 2:58 pm

The shuttle was the biggest mistake NASA ever made.
It was reusable, and as a result it was nearly useless.

It cost millions more to launch than did disposable rockets and didn’t do as good a job as the disposables did.

Philip
Reply to  MarkW
January 11, 2021 4:58 pm

I don’t believe that. NASA simply folded on manned missions after its series of lost life and mechanical failures. Putting a payload on a rocket is quick and dirty, and no real consequences if there is failure.
NASA has become lazy and unimaginative. Which doesn’t bode well for Space Force or the Artemis program to land humans on the moon by 2024, if it won’t harden reusable manned space flight.
Private money is on reusable spacecraft and reusable launch systems. China doesn’t seem to be waiting around either. Their reusable spacecraft test flight in September this year was apparently successful.

MarkW
Reply to  Philip
January 11, 2021 8:37 pm

It doesn’t matter what you choose to believe. The science is unequivocable.

Kpar
Reply to  MarkW
January 12, 2021 12:00 pm

More to the point, Mark, the economics are unequivocal. The shuttle’s main mission was to make access to LEO cheaper, but the bureaucracy made that impossible. As a result, payload to orbit, intended to get down to $100 per pound, actually went up to over $30,000/lb.

The STS failed to achieve its mission, despite the truly remarkable technology.

MarkW
Reply to  Philip
January 11, 2021 9:04 pm

As I’ve said before, these capsules are little more than aluminum cans with a cheap rocket motor and a primitive guidance system.
The guidance system just gets the capsule into the vicinity of the space station, then an astronaut on the space station uses remote control to guide it the rest of the way in.

Most of the rocket motors are only designed for a single use, making them re-usable adds to weight and cost.

Beyond that, where are you going to put the heat sheild.

Even the Dragon uses what the Apollo guys would have called a service module for most of it’s maneuvering in orbit. Only the crew module, a small portion of what is put into orbit, comes back with the crew inside.

MarkW
Reply to  MarkW
January 12, 2021 8:16 am

Another cost that you are ignoring is the cost of post re-entry recovery and refurbishment of the capsule.

Reply to  Joel O'Bryan
January 11, 2021 8:52 pm

Joel,
Wonder if part of the supplies were replacement batteries?
I attended a delightful ASU lecture about the ISS by ex-astronaut & ISS crew member Cadi Coleman who answered my question “How often do they replace the Lithium batteries on the ISS?”. She replied “Oh, about every 5-10 years or sooner if there was a problem. The shuttle was always bringing them up.”

Kpar
Reply to  Joel O'Bryan
January 12, 2021 9:11 am

Joel, all due respect, but I think those are poor examples. Glass and aluminum are endlessly recyclable, and (I believe) Coke bottles are still sterilized and reused, as are glass milk bottles from some dairies.

Your point about “making a vehicle reusable just to carry garbage back to an Earth” is a very valid point.

Last edited 6 months ago by Kpar
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