Space Stuff and Launch Info

In summary, the SpaceX Dragon launch is upcoming, and it appears to be successful. The article has a lot of good information about the upcoming mission, as well as some interesting observations about the Great Red Spot.
  • #106
Below is from the PDF, not that I understand most of it, but it does appear to be blue enhanced. None of my Google searches tied PSP_005000_1000_RGB.NOMAP.JP2 to the image I posted, but then no one ever said I knew what I was doing...

PSP_005000_1000_RGB.NOMAP.JP2 3-color image consisting of RED, BG, and synthetic blue images. The BG image has been warped to line up with the RED.NOMAP image. The BG (blue-green) bandpass primarily accepts green light. The synthetic blue image digital numbers (DNs) consist of the BG image DN multiplied by 2 minus 30% of the RED image DN for each pixel. This is not unique data, but provides a more appealing way to display the color variations present in just two bandpasses, RED and BG.
 
Physics news on Phys.org
  • #107
http://www.esa.int/Our_Activities/Space_Science/ExoMars/Schiaparelli_landing_investigation_makes_progress

As Schiaparelli descended under its parachute, its radar Doppler altimeter functioned correctly and the measurements were included in the guidance, navigation and control system. However, saturation – maximum measurement – of the Inertial Measurement Unit (IMU) had occurred shortly after the parachute deployment. The IMU measures the rotation rates of the vehicle. Its output was generally as predicted except for this event, which persisted for about one second – longer than would be expected.
...
When merged into the navigation system, the erroneous information generated an estimated altitude that was negative – that is, below ground level. This in turn successively triggered a premature release of the parachute and the backshell, a brief firing of the braking thrusters and finally activation of the on-ground systems as if Schiaparelli had already landed. In reality, the vehicle was still at an altitude of around 3.7 km.

This behaviour has been clearly reproduced in computer simulations of the control system’s response to the erroneous information.

This looks like a sensor bounds check problem combined with a signed/unsigned math under/overflow error.
 
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  • #108
Ah, the good old one-sided comparison. "if altitude < 1 km, release parachute". "The altitude is minus 1000 km? Okay, release parachute."

Always catch cases where something goes completely wrong, predict out which input is more likely to be wrong, then ignore that.
 
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  • #109
Why is the event horizon of a black hole so cold? I thought when matter is compressed, it causes it to heat up do to friction.
 
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  • #110
The event horizon is not an object, and it is not made out of matter. It is a region in spacetime. Questions like this would fit better to our relativity forum.
 
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  • #111
This is interesting, it seems large deposits of water may be fairly common on several bodies in our solar system.
http://www.nature.com/nature/journal/vaop/ncurrent/full/nature20120.html

http://www.nature.com/nature/journal/vaop/ncurrent/full/nature20148.html

https://spaceflightnow.com/2016/11/...-be-counted-among-solar-systems-ocean-worlds/

Scientists believe they can explain how an ocean of water is lurking beneath an ice sheet inside Pluto’s prominent heart-shaped region, an iconic frozen landscape discovered during the New Horizons spacecraft ’s flyby last year.

A slushy buried sea under the icy plains of Sputnik Planitia would help counterbalance the gravitational weight of the dwarf planet’s largest moon Charon, which stays fixed above the opposite side of Pluto, researchers reported last week in the journal Nature.
 
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  • #112
ExoMars has been testing the imaging system and the results are awesome.
http://www.bbc.com/news/science-environment-38147682
"We saw Hebes Chasma at 2.8 metres per pixel," said Nicolas Thomas, the camera's principal investigator from the University of Bern, Switzerland.

"That's a bit like flying over Bern at 15,000km/h and simultaneously getting sharp pictures of cars in Zurich."November 30th marks the beginning of the end for Cassini, begins setting up for the ultimate "crash and burn". The 183rd main engine burn should be the last with all following maneuvers performed with thrusters. Nearly 20 years, this has to be one of the most successful missions to date.
http://www.jpl.nasa.gov/news/news.php?feature=6681

Between Nov. 30 and April 22, Cassini will circle high over and under the poles of Saturn, diving every seven days -- a total of 20 times -- through the unexplored region at the outer edge of the main rings.

During these orbits, Cassini will pass as close as about 56,000 miles (90,000 kilometers) above Saturn's cloud tops. But even with all their exciting science, these orbits are merely a prelude to the planet-grazing passes that lie ahead. In April 2017, the spacecraft will begin its Grand Finale phase.

During its grand finale, Cassini will pass as close as 1,012 miles (1,628 kilometers) above the clouds as it dives repeatedly through the narrow gap between Saturn and its rings, before making its mission-ending plunge into the planet's atmosphere on Sept. 15. But before the spacecraft can leap over the rings to begin its finale, some preparatory work remains.And now a note from the "dark side" of space. (I'll bet no one saw this coming :sorry:)
http://www.cnn.com/2016/11/28/politics/space-war-us-military-preparations/index.html

China and Russia are taking aim at America in space with a dizzying array of weapons seemingly borrowed from science fiction. Russia has deployed what could be multiple kamikaze satellites such as "Kosmos 2499" -- designed to sidle up to American satellites and then, if ordered, disable or destroy them. China has launched the "Shiyan" -- equipped with a grappling arm that could snatch US satellites right out of orbit.

"We have very good surveillance and intelligence capabilities, so we can see the threats that are being built," said Hyten. "So we're developing capabilities to defend ourselves. It's really that simple."
 
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  • #113
1oldman2 said:
And now a note from the "dark side" of space. (I'll bet no one saw this coming :sorry:)
http://www.cnn.com/2016/11/28/politics/space-war-us-military-preparations/index.html
Ah, the peaceful US using space for civilian and defense purposes only, while Russia and China think about nothing but harming the US. Yeah, sure.
World leaders couldn't communicate across continents.
One should tell the author about undersea cables, which also handle the vast majority of intercontinental data transfer because their bandwidth is so much better than satellite communication.
Russia has deployed what could be multiple kamikaze satellites such as "Kosmos 2499" -- designed to sidle up to American satellites and then, if ordered, disable or destroy them.
Nothing but speculations. Russia launched a satellite that moved away from its upper rocket stage, then later approached it again. So what? Every docking maneuver at space stations looks similar - and Russia has a lot of experience with those.
According to Russia it is a test of a new propulsion system.
China has launched the "Shiyan" -- equipped with a grappling arm that could snatch US satellites right out of orbit.
You cannot "snatch US satellites right out of orbit". Shiyan-7 made slow approaches to two different satellites. It is reported to have an arm.
A robotic an arm is a key component for larger space stations, like the one China wants to build.
A robotic arm is an ridiculously stupid way to attack satellites. Destroying them with high-speed impacts is much easier and much more effective than grappling anything. Yes it create space debris, but not that much, and with grappling arms you are limited to 1-2 satellites per grappling satellite which is a stupid ratio.
So is the US moving quickly enough to respond to the new threats in space?
"I would say the answer was no," said Gen. William Shelton, former head of Space Command.
Of course you say "no" if saying "yes" means your funding gets reduced.
 
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  • #114
mfb said:
Ah, the peaceful US using space for civilian and defense purposes only, while Russia and China think about nothing but harming the US. Yeah, sure.
There was a certain amount of irony in my comment "The darkside of space" considering the source CNN was quoting.

http://www.space.com/25275-x37b-space-plane.html
The U.S. Air Force's unmanned X-37B space plane has flown three clandestine missions to date, carrying secret payloads on long-duration flights in Earth orbit.

NASA transferred the project to the U.S. military in 2004 - specifically, the Defense Advanced Research Projects Agency (DARPA). At that point, X-37 became a classified project.

The X-37B program is now run by the Air Force's Rapid Capabilities Office, with mission control for orbital flights based at the 3rd Space Experimentation Squadron at Schriever Air Force Base in Colorado. The space planes are built by Boeing's Phantom Works division.

http://www.space.com/9940-secretive-space-plane-meet-37b.html#ooid=lnMnR4cDqNSqpOCj1kbS3mTdnAuJ_zGFhttps://www.rt.com/politics/space-militarization-us-russia-699/
The United States is moving toward the militarization of space and this will change the face of war in the near future, an academician with the Russian Academy of Engineering Sciences has warned.

Only the United States and Israel abstained from voting on the document, rendering it effectively toothless.

Washington’s refusal to cede control of space likely stems from its increasing reliance on space-based systems: An estimated 90 percent of the US Military reportedly uses or depends on space-based systems.

The Russian academic referred the shock over China’s successful targeted destruction of an old orbiting weather satellite in 2007.https://www.scientificamerican.com/article/war-in-space-may-be-closer-than-ever/
The world’s most worrisome military flashpoint is arguably not in the Strait of Taiwan, the Korean Peninsula, Iran, Israel, Kashmir or Ukraine. In fact, it cannot be located on any map of Earth, even though it is very easy to find. To see it, just look up into a clear sky, to the no-man’s-land of Earth orbit, where a conflict is unfolding that is an arms race in all but name.

https://www.stratfor.com/video/militarization-space
http://www.globalsecurity.org/space/library/report/1989/DCA.htm

mfb said:
Of course you say "no" if saying "yes" means your funding gets reduced.
This is a big problem here whenever the government is involved.
 
  • #115
Washington’s refusal to cede control of space likely stems from its increasing reliance on space-based systems: An estimated 90 percent of the US Military reportedly uses or depends on space-based systems.
What are the other 10% and why don't they use GPS?
Statements like that are misleading. They suggest some super-advanced system where everything depends on specialized satellites, while in reality it just means every mobile electronic device has GPS.
Oh well, I stopped hoping for somewhat reasonable rt.com content long ago.
 
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  • #116
mfb said:
Oh well, I stopped hoping for somewhat reasonable rt.com content long ago.
RT isn't one of my regular sources for linking, I used that one in the interest of symmetry, you know to balance out the American news sources spin. :wink:

I'm glad I read https://www.physicsforums.com/insights/vacuum-fluctuation-myth/ before I read
http://www.space.com/34852-neutron-star-shows-quantum-property-evidence.htmlA strange quantum phenomenon predicted more than 80 years ago finally may have been observed in nature.

In classical physics, a vacuum is entirely empty, but in quantum physics, there are "virtual particles" that are constantly appearing and vanishing in the vacuum of space. Heisenberg and Euler used a theory called quantum electrodynamics (QED) to show how the quantum properties of a vacuum would influence light waves.This I found rather cool also. :smile:
http://www.space.com/34850-private-moon-race-apollo-17-site.html
A Berlin-based group of rocket scientists and engineers are aiming to land a pair of privately funded Audi-branded robotic rovers on the moon and drive them to inspect NASA's Apollo 17 lunar roving vehicle, marking 45 years since humans last drove on another world.
ptscientists-moon-rover-apollo17b.jpg
 
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  • #117
1oldman2 said:
A Berlin-based group of rocket scientists and engineers are aiming to land a pair of privately funded Audi-branded robotic rovers on the moon and drive them to inspect NASA's Apollo 17 lunar roving vehicle, marking 45 years since humans last drove on another world.

you mite want to reread what you wrote there and offer an edited version :wink:
it isn't valid in it's current formedit ... not your fault, noting of course it's the bad reporting that is incorrect

They are combing robotic rovers and manned rovers into the one sentence without clarifying the situationDave
 
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  • #118
davenn said:
it's the bad reporting that is incorrect
:sorry: Gets me every time. Thanks dave. :smile:
I've decided not to edit as an example of what can be found in professional literature these days, it is a cool concept... Audi will have some good PR for there ad dept. :cool:
 
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  • #119
1oldman2 said:
I've decided not to edit as an example of what can be found in professional literature these days,

yeah it seems, at times, there is little proof reading done :frown:
 
  • #120
1oldman2 said:
I've decided not to edit as an example of what can be found in professional literature these days, it is a cool concept... Audi will have some good PR for there ad dept.

It is not obvious to me what type of issue with the news story you and davenn are referring to. Is it just bad english (for some reason) or is there something more seriously wrong with it?
 
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  • #121
Filip Larsen said:
It is not obvious to me what type of issue with the news story you and davenn are referring to. Is it just bad english (for some reason) or is there something more seriously wrong with it?
I guess it comes down to personal preferences, I was more focusing on the "branded" rover.
 
  • #122
Note that "vacuum birefringence" is not actually in vacuum - it is in a strong magnetic field. Light-light-interaction, again a type that hasn't been seen before (ATLAS found light by light scattering a month ago).The Berlin group is now the 5th group with a launch contract for the Google Lunar X-Prize, at least two more groups plan to get a launch contract this month (they have to, otherwise they are out).
 
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  • #123
A Progress cargo ship en route to the ISS has gone missing around the time it should have entered orbit.
http://www.bbc.co.uk/news/science-environment-38173002

Edit: Two updates from ISS Updates twitter feed:
Social Media Reports of an explosion in the skies over Tuva, Russia around the time #ProgressMS04 vanished. Location also good match.
Roscosmos: #ProgressMS04 failed to reach orbit due to a failure of the third stage of the #Soyuz U rocket around 190km above South Siberia.
 
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  • #124
Filip Larsen said:
It is not obvious to me what type of issue with the news story you and davenn are referring to. Is it just bad english (for some reason) or is there something more seriously wrong with it?

no, it's not bad English, it's a misleading statement

the Audi branded ( not that it matters where the funding comes from) are ROBOTIC, ie. unmanned
To end the statement with ... "marking 45 years since humans last drove on another world."
is totally pointless and irrelevant when referring to ROBOTIC roversDave
 
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  • #125
Jonathan Scott said:
A Progress cargo ship en route to the ISS has gone missing
I know it's rocket science and it's hard, but I'm surprised that routine launches like this regularly run into new snags.
Not just Russian ones, it seems that any rocket launch starts with a baseline of about 80% likely to succeed.
 
  • #126
rootone said:
I know it's rocket science and it's hard, but I'm surprised that routine launches like this regularly run into new snags.
Not just Russian ones, it seems that any rocket launch starts with a baseline of about 80% likely to succeed.

pretty scary if it's a maned launch
 
  • #127
rootone said:
I know it's rocket science and it's hard, but I'm surprised that routine launches like this regularly run into new snags.
Not just Russian ones, it seems that any rocket launch starts with a baseline of about 80% likely to succeed.
The long-term average is about 5% failure rate for unmanned rockets and 1% for manned missions. This year we had 74 launches, 72 of them were successful (5 of them were manned). The SpaceX incident is not included because it was not a launch attempt.
 
  • #128
A good piece from Planetary.org.
http://www.planetary.org/blogs/jason-davis/2016/20161201-whats-the-matter-russias-rockets.html

By my calculations-which are outlined at the end of this article-this marks the fifteenth failure of a Russian rocket in 6 years. Of those, all but two were related to upper stages. Seven were tied to the Proton's Briz-M, while Soyuz stages have been implicated five times. Three Soyuz failures involved the rocket's native third stage, and the other two were related to the Fregat.
 
  • #130
Upcoming stuff. :smile:
http://www.planetary.org/blogs/gues...he-next-nasa-discovery-mission-selection.html

If NASA’s managers hold to their schedule, we will learn sometime this month what NASA’s next planetary mission will be. This will bring to a close a two-year process that saw 27 teams of scientists and engineers propose missions for the agency’s Discovery program, followed by a winnowing of the field to five finalists. Out of the process should come the selection of one (and if the gods smile, two) missions that will launch in the early 2020s to study either Venus or the asteroids.

It looks like the next Falcon won't fly in December after all.
http://www.space.com/34934-spacex-return-to-flight-rocket-launch-january.html
SpaceX is now eyeing early January for its next mission, the first one the company will have launched since a Sept. 1 explosion grounded its fleet of Falcon 9 rockets.
http://spacenews.com/spacex-punts-falcon-9-return-to-flight-launch-to-january/

I'm still waiting to hear if the Rocketlab Electron will get to make the test launch by the end of the year as they planned, pretty cool "midsize" launch system. The rutherford motor is particularly interesting as an example of how new technologies like 3D printing are changing rocket design.
http://www.rocketlabusa.com/electron/


Also in the up and coming small satellite launching field, these guys just might have a pretty good plan as well. The launch plane itself is also worth a close look, regarding the hypersonic aspect.
http://www.satellitetoday.com/launc...alks-plans-weekly-launches-hypersonic-travel/

Progress with GOLauncher 1 will feed into GO’s orbital air-launch system GOLauncher 2, a two-stage rocket system designed to carry roughly 40 kilograms to Low Earth Orbit (LEO) for a around $2.5 million. In 2015, the company reported to Via Satellite that it had 11 Letters of Intent (LOI) from prospective customers for the smallsat launch services.

In other news... Siberia took another meteor strike, kind of getting to be a habit for that region.
(I don't think the author of this piece is discerning the difference between a meteor and a meteorite)
http://www.astrowatch.net/2016/12/siberian-meteorite-could-be-up-to-15.html

The meteorite that exploded above Russia’s southern Siberian republic of Khakassia Tuesday could be about 10-15 meters in diameter, a leading Russian space scientist told TASS. "Obviously, the meteorite wasn’t big. Judging by the fact that it burned up or exploded before reaching surface, it’s obvious that it can hardly be more than 10 or 15 meters in size and that apparently it is not made of iron," Head scientist of Space Research Institute (IKI) of Russian Academy of Sciences Natan Eismont said.
 
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  • #131
It appears black hole, gravity wave "echoes" are in the news in a potentially upsetting way.
http://www.nature.com/news/ligo-black-hole-echoes-hint-at-general-relativity-breakdown-1.21135

It was hailed as an elegant confirmation of Einstein’s general theory of relativity - but ironically the discovery of gravitational waves earlier this year could herald the first evidence that the theory breaks down at the edge of black holes. Physicists have analysed the publicly released data from the Laser Interferometer Gravitational-Wave Observatory (LIGO), and claim to have found "echoes" of the waves that seem to contradict general relativity’s predictions.

The echoes could yet disappear with more data. If they persist, the finding would be extraordinary. Physicists have predicted that Einstein’s hugely successful theory could break down in extreme scenarios, such as at the centre of black holes. The echoes would indicate the even more dramatic possibility that relativity fails at the black hole’s edge, far from its core.
 
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  • #132
It is confusing if you don't mark quotes as such.

They claim a significance of 2.9 sigma: I'm not convinced.
In addition, figure 4 looks odd. To evaluate the look-elsewhere effect, they use a search window with a width below 1%. Compare this to the Delta t uncertainty of 3 to 10%. Huh?
 
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  • #133
mfb said:
It is confusing if you don't mark quotes as such.
Sorry, I meant to edit and add the quote marks but got distracted.
mfb said:
They claim a significance of 2.9 sigma: I'm not convinced.
To be perfectly honest, I had to go to http://news.mit.edu/2012/explained-sigma-0209
before I responded to this. From my understanding of the Sigma rating system, 2.9 would be considered a little short of the "gold standard" however it could be relevant (in certain contexts). Hopefully with everyone's attention on these echoes as well as the upgraded LIGO online some solid answers will be forthcoming in the near future.
I found this,
[The echoes could be a statistical fluke, and if random noise is behind the patterns, says Afshordi, then the chance of seeing such echoes is about 1 in 270, or 2.9 sigma. To be sure that they are not noise, such echoes will have to be spotted in future black-hole mergers. "The good thing is that new LIGO data with improved sensitivity will be coming in, so we should be able to confirm this or rule it out within the next two years."]
as well as this,
[But although the team’s paper offers "tantalizing hints" of a departure from general relativity, so far these are just hints, says Giddings. And he questions whether Afshordi’s mirror model can ever reveal the cause of the deviations from general relativity - in part because the theories that predict them only provide vague descriptions of what replaces the event horizon, making it tough to accurately model them. A "basic problem here is we don’t know what is a good physical description of a firewall, or fuzzball"]
to be fairly representative of the articles overall ambiguous stance, (just my personal opinion) I guess overturning general relativity is going to take some serious proof, (as well as one hell of a sales pitch).
 
  • #134
then the chance of seeing such echoes is about 1 in 270, or 2.9 sigma
If they would have invented their model before the observations came in, maybe (but even then the choice of the interval in figure 4 is highly questionable). If they had a look at the data before making their model, that approach doesn't work, you can always tune the model to better match statistical fluctuations. In addition, I am always skeptical when data is analyzed by external people - it is very easy to miss some systematic effect.
 
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  • #136
A Transient Transit Signature Associated with the Young Star RIK-210

10-15% dips in brightness, periodic with the same period as the stellar rotation, always at the same phase but not always at the same strength. And no indication of a protplanetary disk that could offer a good explanation for the dips.
Page 3 with figure 2 is the main plot.

Edit: Link to abstract works again.
 
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  • #137
Earlier this month, on Dec. 3, accelerometers at NASA’s Goddard Space Flight Center (GSFC) detected "anomalous readings" in a portion of the James Webb Space Telescope (JWST). These "readings" took place during vibration tests being conducted to simulate anticipated launch conditions.
Read more at http://www.spaceflightinsider.com/m...elescope-testing-anomaly/#y0lXMydlLKdPMTqu.99

Cool Physics but wouldn't Aliens have been a "funner" explanation. ?
http://www.astrowatch.net/2016/12/avalanche-statistics-suggest-tabbys.html

Now a team of scientists at the University of Illinois at Urbana-Champaign-physics graduate student Mohammed Sheikh, working with Professors Karin Dahmen and Richard Weaver-proffer an entirely novel solution to the Tabby’s star puzzle. They suggest the luminosity variations may be intrinsic to the star itself.
 
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  • #138
Does anyone happen to know if Dark Energy goes through the "loss" like this article describes for Dark Matter ?
http://journals.aps.org/prd/abstract/10.1103/PhysRevD.94.023528
http://www.astrowatch.net/2016/12/russian-physicists-measure-loss-of-dark.html

"This means that in today’s Universe there is 5% less dark matter than in the recombination era. We are not currently able to say how quickly this unstable part decayed; dark matter may still be disintegrating even now, although that would be a different and considerably more complex model," says Tkachev.
 
  • #139
We need the whole time evolution of the universe to get a strong evidence of dark energy, measuring it as function of time (precise enough to see something like that) would need much more precise measurements.

Even for dark matter, a 5% reduction is just slightly favored, the measurements are consistent with 0%.
 
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  • #140
This is an interesting sequence, I came across them almost simultaneously. Rocket science is a great equalizer no matter what nation pursues it.
http://www.planetary.org/blogs/guest-blogs/2016/1227-china-outlines-its-space-ambitions.html
"China has just released a new white paper on its policy and activities in space, outlining ambitious deep space exploration, human spaceflight and space science projects as major priorities for the years up to 2020 and beyond.

There’s a lot going on in this comprehensive document but, after a quick look at recent progress, it’s definitely worth focusing on China’s deep space exploration plans."http://spaceflight101.com/long-march-2d-gaojing-partial-launch-failure/
"Although initial reports claimed the launch was a success, orbital data showed that the two main payloads did not reach the intended orbit and a number of flight sequence events did not match up with the pre-launch predictions."

More on that Chinese launch "anomaly".
http://www.astrowatch.net/2016/12/chinas-long-march-2d-places-two.html

I have avoided mentioning the "Trumping" of NASA to keep this thread from getting political but I can't resist this piece.
http://spacenews.com/earth-scientists-are-freaking-out-nasa-urges-calm/
At a time when NASA Earth scientists are concerned their research may be scuttled by the incoming Trump administration, the space agency’s top science official is preaching pragmatism and unity.

The names of the two key Trump administration figures who will have the most significant impact on NASA’s future - the new NASA administrator and the director of the White House Office of Science and Technology Policy - have not been announced. To put that in scientific terms, all the rumor and discussion swirling around the scientific community about NASA’s future under a Trump presidency is noise, "not signal," said Thomas Zurbuchen, who took over as the leader of NASA’s Science Mission Directorate in October.

Also I should add, this is an excellent article, very good reading.
http://www.planetary.org/20161229-spaceflight-2017-p1.html
 
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