ESA Rosetta, news, updates and discussion Options

[tty]

I can't understand why people would want to go metric, after all what's wrong with the old (Imperial?) system:

12 lines to an inch, 12 inches to a foot, 3 feet to a yard, 220 yards to a furlong, 8 furlongs to a mile and 3 miles to a league.

16 drams to an ounce, 16 ounces to a pound, 14 pounds to a stone, 2 stones to a quarter, 4 quarters to a hundredweight and 20 hundredweight to a long ton.


Now that is what I call creative units, and if it leads to an occasional case of unintentional lithobraking, so what.

[Greg Hullender]

Don't forget troy ounces. That's what makes the joke about "which weighs more, a pound of gold or a pound of feathers" work. (Answer: a pound of feathers weighs more, because a pound (avoirdupois) of feathers is 453 grams but a pound (troy) of gold is only 373 grams.)

--Greg

[helvick]

The part that I find really odd is that "Imperial" measures are fundamentally defined by calling on metric SI base units e.g. the international avoirdupois pound is defined officially as being equal to exactly 453.59237 SI grams. This opens up a whole other argument about pounds being units of force and not mass but I really don't think we should go there again.

In any case surely shouldn't the Pound be defined as equal to the weight of one of George Washington's boots or something?

[nprev]

Well, one of my latest classes is a crash physics review rolled into new stuff for space sensors, and all I can say is thank God for the metric system. I have enough trouble figuring out where to put decimal points without worrying about duodecimal/hex unit conversions to boot!!!

[dvandorn]

In any case surely shouldn't the Pound be defined as equal to the weight of one of George Washington's boots or something?

Actually, the yard used to be the distance between a liege lord's nose and the tip of his finger on an outstretched arm. No matter that a particular lord's lands had a different length for the yard than anyone else -- it placed his stamp on everything built during his reign.

-the other Doug

[ustrax]

Precious...Just precious...

"For detailed information regarding Rosetta's Mars Swing-by, please consult the Trajectory Status Presentation given by Trevor Morley from the ESOC Flight Dynamics Team for the Mars Swing-by Preparation Readiness Meeting that took place on the February the 2nd and which was kindly made accessible to spacEurope by Dr. Gerhard Schwehm."

[climber]

Isn't it ironic that all this "discution" about metric vs imperial occurs in the Rosetta's topic ?
M.Champollion, where are you?

[Greg Hullender]

I think it's because the switch to the metric system is almost the latest news we have from over there.

--Greg ;-)

[Guest_AlexBlackwell_*]

Rosetta correctly lined up for critical Mars swingby
ESA
15 February 2007

As an aside, several Rosetta instruments and investigations-related papers have been posted over the past few weeks in the "Online First" section of the journal Space Science Reviews. These papers will be assigned to a specific issue(s) at a later date.

[GravityWaves]

Here's everything Rosetta's has to give...

Looks like a great craft but what makes the Rossetta lander so different to the stunt the Japanese tried to pull with Itokawa

[djellison]

Minerva wasn't much of a scientist - camera, temp data and the ability to 'bounce' itself around a little.

Philae - however...

Rosetta Lander Scientific Instruments

Investigation of comet materials COSAC MPAe D chemical analysis with mass spectrometer (MS) and gas chromatograph (GC); pressure sensor Ptolemy Open University UK isotope analysis (ion trap, GC) APX MPCh D element analysis ( Alpha Xray Spectrometer) Cameras for viewing of the comet core ÇIVA IAS F panorama, stereo and microscope cameras, imaging infrared spectrometer ROLIS DLR D landing and down looking camera Investigation of comet core structure SESAME DLR D seismic measurements, dust monitoring, permittivity probing CONSERT CEPHAG/LPG F microwave tomography MUPUS Univ. Münster D penetrator with thermal sensors Plasma and magnetic environment ROMAP Univ. Braunschweig D magnetic field and plasma monitoring Sample Retrieval SD2 Politecnico di Milano I drilling and sample distribution

[edstrick]

"Philae - however..."

The entire Rosetta mission is entirely comparable to Galileo/Jupiter Probe, and Cassini/Huygens and in older times, Viking Orbiters and Landers in ambitiousness and in the scientific scope and variety of instruments. This is one big, impressive mission.

[mchan]

Indeed. I think of it as CRAF+. Kudos to ESA for stepping up with an enhanced mission after NASA had its budget slashed and had to renege on some of its international commitments.

[Guest_Analyst_*]

Correct. This is a flagship. It will give us much more return than Deep Impact, Contour and Stardust combined.

Not to discount the samples from Stardust or the possibility to study 3 different comets with Contour. But long term study is the key. To see the change, not to take snapshots. Using a suite of instruments. You can repeat observations to answer new questions. This is something Contour or Deep Impact could not do. Deep Impact in particular has been a big disappointment. For me it looked more like an engineering demonstration than a science mission. Stardust is a little bit different: There you have the material and can study it again and again. But these very short flybys should be something of the past (This is even true for New Horizons, but hey, there is no way to orbit Pluto, so you must flyby).

If I look at Discovery missions so far, many did carry only very limited instruments: MPF, Stardust, Contour, Deep Impact. On the other hand, orbiters were much more productive: NEAR, Lunar Prospector, hopefully Messenger and Dawn (although Dawns instruments are very limited too). Genesis is a little bit different, but Kepler has a very limited scope too.

I go as far and say: One flagship like Cassini (3 billion $) gives you much more return than 8 Discovery missions (400 million $ each). Discovery missions need a very large amount of their budget just to built the spacecraft bus and launch it. The science instruments are only tiny fraction. This relationship get better the bigger the mission.

Analyst

[djellison]

But of course, one LV failure with 8 discovery missions is a little less drastic than a single LV failure on a flagship mission. There are benefits to spreading things out a little.

Doug