Scary times for Europe's comet-chaser Rosetta (Update)

A photo released by the European Space Agency on November 13, 2014 shows an image taken by Rosetta's lander Philae on the surfac
A photo released by the European Space Agency on November 13, 2014 shows an image taken by Rosetta's lander Philae on the surface of Comet 67P/Churyumov-Gerasimenko
Europe's pioneering probe Rosetta battled breakdowns with navigation and communication with Earth after it ran into blasts of dust and gas from the comet it is tracking, mission control said Thursday.

Swooping close to Comet 67P/Churyumov-Gerasimenko, Rosetta "experienced significant difficulties" last weekend, the European Space Agency (ESA) said.

"The spacecraft has now been successfully recovered, but it will take a little longer to resume normal scientific operations," ESA said in a blog.

On its Twitter feed, Rosetta said, "Had some difficulties... thanks for kind messages. I'm feeling much better & hoping to resume normal activities soon!"

Behind the official statements, though, it was clear the 1.3-billion-euro ($1.4-billion) mission had had some heart-stopping moments.

"Rosetta won't be going so close (to the comet) again," said operations manager Sylvain Lodiot, who said his team had had a sleepless weekend.

Rosetta has been circling "67P/C-G" since last August, catching up with the wanderer after a 10-year, 6.5-billion-kilometer (four-billion-mile) chase across the heavens.

The mission seeks to unveil the secrets of comets, believed to be time capsules from the birth of the Solar System.

The target comet is getting closer to the Sun with every second, and the solar heat is causing its surface to warm.

This in turn is causing dust to be stripped away and gases to heat and blast out into space.

It is this spectacular show that, with luck, can be seen from Earth as a fiery "coma" when a comet passes close by.

For Rosetta, though, the outpouring was a problem on an unexpected scale, as the orbiter raced to within 14 kilometres of the surface.

A handout released by the ESA/ATG medialab on November 12, 2014 shows an artists impression of the European probe Philae separat
A handout released by the ESA/ATG medialab on November 12, 2014 shows an artists impression of the European probe Philae separating from its mother ship Rosetta and descending to the surface of comet

Flying through dense, outflowing gas and dust exposed the spacecraft's solar panels, like outstretched wings, to drag.

Another problem was that Rosetta is designed to navigate by locking on to the stars—and its trackers mistook hundreds of pieces of comet debris for stars.

As a result, the spacecraft began to drift and its high-gain antenna, used to send and receive signals from ground stations on Earth, started to point away from home... and communications began to falter.

"The problems began on Saturday morning and lasted until Sunday night. It was pretty hairy stuff," said Lodiot, in charge of Rosetta's operations at ESA's facility in Darmstadt, Germany.

"On Sunday morning, we were losing communications with Rosetta. I watched the signal fade bit by bit. It was dramatic," Lodiot told AFP by phone.

Rosetta then automatically placed itself into safe mode, turning off all instruments to try to keep in touch with the distant Earth.

"Fortunately, the star trackers came back online when the probe was about 75 kilometres from the comet" and the craft was able to find its position once more, Lodiot said.

By Monday, ground teams had brought Rosetta back to normal status.

"The spacecraft is in perfect shape. It did not suffer any damage," Lodiot said.

Rosetta is now at a safer distance of 400 km from the comet, and will be brought back to within 100 km, Lodiot said.

Months of work wasted

However, future flybys will have to be reassessed to take into account the dust and gas peril, which is likely to worsen as the comet heads towards perihelion, its closest point to the Sun.

"Months of work (on planning the trajectories) will have to be binned," Lodiot lamented.

The changes also mean that Rosetta's science programme—the craft is scanning the comet with 11 instruments—will need to be reviewed.

On November 12, Rosetta sent down a fridge-sized robot lab, Philae, which carried out a 54-hour roster of experiments before its battery ran out of power.

The lander is believed to be in the shadow of a cliff, preventing its solar panels from getting enough sunlight to power up. The mission hopes Philae will revive as 67/P gets closer to the Sun.

Rosetta on Thursday was 423 million km from Earth and 293 million km from the Sun, according to the mission's website (sci.esa.int/where_is_rosetta/ ).

Perihelion will be on August 13, when the comet will be 186 million km from the Sun.


Explore further

Comet mission in bid to contact dormant Philae probe

© 2015 AFP

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Apr 02, 2015
OK. Sure.

Apr 02, 2015
I'll bet it took an electric zap!

Apr 02, 2015
For Rosetta, though, the outpouring was a problem on an unexpected scale, as the orbiter raced to within 14 kilometres of the surface.


Because they choose to ignore plasma processes in favor of the "gas models" that aren't even close.

Flying through dense, outflowing gas and dust exposed the spacecraft's solar panels, like outstretched wings, to drag.


I'd be interested to know this density that caused all this drag. Although a charged object approaching a differently charged object within an EM field will experience force as well. Especially if the object flies through a discharge path, as it so obviously did.

Another problem was that Rosetta is designed to navigate by locking on to the stars—and its trackers mistook hundreds of pieces of comet debris for stars.


How can dust be confused with stars? Those instruments detect at certain frequencies, that stars produce. Probably, the dust is still arcing like embers in the wind, just as the stars are.

Apr 02, 2015
Only three EU nutters commenting?

Where is Hannes and the rest of the delusional tribe?

Apr 02, 2015
The star tracker is a 1024x1024 pixel CCD, with a 16 degree field of view. Of course it could mistake sunlit dust for stars, since starlight is illuminating them.

The orbital dynamics of Rosetta around such a low mass object would make even a little drag a problem.

Apr 03, 2015
Because they choose to ignore plasma processes in favor of the "gas models" that aren't even close
@cd
same old tired LIE again?

Except that your "version" of asteroid, comets and STARS is not only wrong, but completely debunked as well...
wanna see another nail in the coffin of your pseudoscience?
http://www.scienc...abstract

your eu paradigm not only does NOT make the prediction, but does NOT match the observations

Then you make unfounded conjecture in your post above and you have absolutely NO evidence of any of it... nor do you even take a little time to review the actual machinery or data from Rosetta... but you still think you are correct?

That's called Dunning-Kruger

So, what charge should said comet have?
What charge would arc to Rosetta and how would it affect the equipment?
make SPECIFIC predictions so we can all see

epic fail for eu and you


yep
Apr 03, 2015
Epic you do not have a clue.
http://www.nasa.g...osphere/
To bad for you, EU has been spot on with comet predictions.
That nail in the coffin and you are definetly full of wind.

Apr 03, 2015
@yep

Epic you do not have a clue.
http://www.nasa.g...osphere/
To bad for you, EU has been spot on with comet predictions.
That nail in the coffin and you are definetly full of wind.


LMFAO!


yep
Apr 04, 2015
Enough charge to emit x-Rays and other fun spectra!
http://www.scienc...abstract
Yes pretty shocking to realize how simple a 99% plasma reality can be. It eliminates Big Bang, black holes, dark matter, and other magical nonsense your ultra "dense" miracle science has faith in.

Apr 04, 2015
http://www.nasa.gov/press/2014/november/mars-spacecraft-reveal-comet-flyby-effects-on-martian-atmosphere/
@yep
there is absolutely NOTHING in that link to undermine astrophysics or in any way support your eu over the standard model
it is all in your head
other magical nonsense
and apparently, you cannot read the whole study there either...
there is NOTHING in the science magazine study that in any way demonstrably promotes eu over the standard model either

Neither is there evidence in ANY link, that shows or demonstrates that your eu has any kind of superior predictability over the modern standard model

if you HAD such evidence, i am sure that it would have been in study form and linked, but there is NOTHING, therefore, you are still promoting PSEUDOSCIENCE or a faith in a belief over the science that is linked

it also demonstrates that you are not comprehending the science linked


Apr 04, 2015
Enough charge to emit x-Rays and other fun spectra!
@yep
it also discusses the why
there is the signature of CXE created line emission in our data, and the simplest CXE models depend on the solar wind minor ion flux and the comet neutral gas flux alone, an alternative explanation is that the solar wind proton flux is not a good measure of the solar wind minor ion flux in the flare experienced by C/LINEAR. Examination of the ACE ULEIS ultrasoft ion spectroscopy data for H, He4, C, O, Ne, Fe, taken at L1, seemed to bear this out: the solar wind fluxes for H and the heavier ions at low energy are identical, whereas the highest energy minor ion fluxes, >1 MeV/nucleon, have a pronounced peak on 14 and 15 July 2000 not found in the proton curves. The peak at higher energies is especially pronounced for He and Fe; the relative height of the peak may explain the unusual ratio of C:N:O lines found in our spectra.
cont'd

Apr 04, 2015
@yep cont'd
Shifting the measured C+5 flux for the expected Carrington rotation delay produces agreement with the observed EUVE count rates (Fig. 5). If true, why the proton-minor ion correlation breaks down for a flare versus a sector boundary crossing is not clear, and is most probably due to the detailed physics involved with solar flare generation. In either case, the usefulness of cometary x-ray emission for understanding the solar wind environment in all parts of the solar system is evident (37).
so your two posts makes the inference that the comets what?
the study is pretty specific and there is NOTHING in it to counter or undermine the standard model
in fact, it is simply expounding upon our knowledge as well as defining observations

it SURE doesn't support eu comet hyper-stupidity
you still haven't been able to defend the eu claims re: Shoemaker-Levy 9 but now you want to say eu is accurate?
LOL


Apr 06, 2015
http://tmgnow.com...met.html


@yep

I hope you didn't waste your money on Macanney's outrageously priced cds.
But then again, that's is job, to con the gullible idiots.

http://www.jmccan...nce.com/

yep
Apr 06, 2015
The question was what charges does a comet have, and that's what these posts are about.
https://www.rug.n...02).html

Apr 06, 2015
Listen, moron: actually READ the thesis, and you'll discover that comets have no charge: the gases outflowing from their surfaces, and which make up their comas, are ELECTRICALLY NEUTRAL: precisely what would be expected from a cold, icy structure being warmed by the Sun.

Actually, you are the moron. You acknowledge the comet/coma are differently charge than the solar wind but refuse to acknowledge there is a possibility of a discharge. This is the height of stupidity. The comet/coma will be required by known physics to equalize to it's environment, whether it is "electrically neutral" or not is meaningless. The coma is the evidence of the discharge between the nucleus and the solar wind. You can choose to believe want you want, but we're discussing plasma, not "neutral gas", the physics are completely different.

Apr 06, 2015
There's something else that needs to be said about the solar wind, and it's something that is often misunderstood.


And you so obviously misunderstand it, space plasma is "quasi" neutral. That is to say that areas within any plasma can form different charges and separate themselves with double layers and Langmuir sheaths.

You have a gas bubble in your brain which is preventing real knowledge of plasma to enter. You have all sorts of theoretical knowledge of plasma which has been shown to be false for decades, let's try reconvening in the 21st century.

Apr 07, 2015
Under what peculiar circumstances would a plasma decide to differentiate itself into regions of different charges?

Do we need to revisit the basics developed some 90 years ago? You can start here;

http://www.iaea.o...0222.pdf

First paragraph;
"SINCE THE TIME OF LANGMUIR, we know that a double layer (DL) is a plasma formation by which a plasma - in the physical meaning of this word- protects itself from the environment. It is analogous to a cell wall by which a plasma - in the biological meaning of this word - protects it self from the environment."

No magic required, just the known properties of the matter.
it is essentially "frozen in" within the solar wind

LOL, "frozen-in" fields? Is it still the 50's yet, or are we in the 21st century? If you continue to read the above paper you'll read how "frozen-in" fields are just more pseudoscience.

Talk about a parrot, the difference is your parrot is dead!

Apr 07, 2015
@cantdrive

"(Of course all theories of plasma
phenomena in regions which cannot be investigated by in situ
measurements are by definition speculative!)"

My favorite quote from your link.

Apr 07, 2015
@cantdrive

"(Of course all theories of plasma
phenomena in regions which cannot be investigated by in situ
measurements are by definition speculative!)"

My favorite quote from your link.

Which makes those that are supported by laboratory evidence even more relevant, such as those in use by Plasma Cosmologists and EU theorists. Unlike the purely theoretical constructs used by standard theorists.

Apr 07, 2015
[
Which makes those that are supported by laboratory evidence even more relevant, such as those in use by Plasma Cosmologists and EU theorists. Unlike the purely theoretical constructs used by standard theorists.


Like the EU theories about the Grand Canyon, craters, and failed comet predication?

Your comment about the Standard Theory is a sign of your ignorance.


Apr 07, 2015
@unavontuba

I didn't know that besides being anti-science that you're also an EU fan.

Apr 09, 2015
...for encouraging me to look much more closely at literature (but NOT the raving EU lit!)


EU mumblings (sorry: "theories") have no means to explain these phenomena: hardly surprising, really.


How would you know when you don't even look at the "raving EU lit"? You do know the "raving EU lit" is based on laboratory evidence beginning over 100 years ago by Kristian Birkeland and his "Little Terella" experiments. He was able to reproduce the coma and multiple tails. Once again, his theories were supported by empirical evidence.

https://books.goo...;f=false

And of course, "it turns out to rather more complex than you had envisioned"...But you can't envision much though can you.

Apr 10, 2015
@cantdrive

I've wasted a lot of hours reading the links you and others have provided.. I've tried watching the ThunderBolts videos but gave up with a mixture of laughter and disgust.

Apr 10, 2015
I'm not talking about the Birkeland currents and the aurorae, nor about the lab experiments on plasmas, nor about Alfvén's good work on magnetohydrodynamics, nor indeed about double layers.


That is exactly what it is about, because if you claim "good science" to the presence BC's and the DL's they must have, how they drive the aurora and many other phenomena, empirical laboratory evidence on plasmas, and Alfven's discovery and subsequent dismissal of the applicability of MHD to the understanding of plasma behavior on the cosmic scene, then you cannot claim the EU is "laughable. You are contradicting yourself because the EU is based upon exactly those things. It should be mentioned Peratt was a protege of Alfven and was charged by the USDOE to study, improve, and secure the country's nuclear arsenal. His only "crime" was applying his lab findings to cosmic proportions. My question is, why shouldn't the results be applied to cosmology. Empiricism IS science.

Apr 11, 2015
What it's about are the many ridiculous claims made by proponents of EU, like "electrical machining" (EM) of planetary surfaces


So you choose hypothetical reasoning of direct laboratory empirical evidence? Typical.

http://benthamope...-185.pdf

BTW, nobody claimed there are not impact craters, just that not every crater is from impact. The standard theory requires epicycles and unicorns to explain many of the phenomena, not EU. Many canyons and other features on Mars simply cannot be explained by "water that may have once existed", you know the usual DM reference the ST likes to lean on.

The stupendous energies in electrical discharges needed to produce such stuff would turn everything around to glass.


http://en.wikiped...rt_glass

Vitrified sand is very common, but I guess you think aliens did it...


Apr 11, 2015
Edit:

"So you choose hypothetical reasoning OVER direct laboratory empirical evidence? Typical."

Apr 11, 2015
No: having been well schooled, I choose objectivity, good scientific reasoning and a trained critical faculty. Oh, and math, of course.

"Well schooled" is exactly right, a "trained critical faculty". LOL, I couldn't have said it better myself. "I choose objectivity" is the opposite of what you claim and how you act. The fact that you would choose to ignore direct empirical evidence such as the linked experiments to support mathematical epicycles says it all!

Apr 11, 2015
@unavontuba

I didn't know that besides being anti-science that you're also an EU fan.
I see no need to bully people over their personal beliefs. Why must you?


Apr 11, 2015
@unavontuba

I didn't know that besides being anti-science that you're also an EU fan.
I see no need to bully people over their personal beliefs. Why must you?


LMFAO!!!

Apr 12, 2015
@cantdrive

I've wasted a lot of hours reading the links you and others have provided..


LOL, so your hobby is wasting time on cranks,.. was it worth all those 5's?

Apr 12, 2015
and all the good ones are backed up with considerably more than "direct empirical evidence"

Please explain, what exactly is "more considerable" than empirical evidence. And equation after equation is not empirical evidence. Sure use maths all you want to further support or falsify your laboratory findings, but an entire edifice built upon purely mathematical constructs is not science. It's merely metaphysics.

Apr 12, 2015
@noumenon

@cantdrive

I've wasted a lot of hours reading the links you and others have provided..


LOL, so your hobby is wasting time on cranks,.. was it worth all those 5's?


Not my hobby but it was curiosity that led me to follow the links. My number one take-away is that EU advocates lack critical thinking skills and are highly gullible.

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