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0 pointskartikkumar11y ago0 comments

Sure. You can look up the abstracts for the Rosetta sessions at DPS to get a better sense of the work that has been done and is being conducted [1]-[3]. Some of the highlights presented at DPS, based on the talks that I attended, include:

* Further image analysis has shown that Comet 67P likely has very low strength, perhaps in areas even just powders held together by van der Waals forces

* The Microwave Instrument for the Rosetta Orbiter (MIRO) has clearly detected water (+ isotopes) in the coma of the comet. MIRO results indicate that the top layer is dusty and loose.

* There is a clear thermal signature from the neck of 67P that doesn't match expected results.

* Magnetic field variations in the neighborhood of 67P pose an interesting puzzle that will hopefully shed more info about the core (http://blogs.esa.int/rosetta/2014/11/11/the-singing-comet/).

There were also a few sessions on other comets that have made the news (e.g., Siding Spring which had a close encounter with Mars recently)[4]-[6].

To address the issue of why any of this is important at all. It hits at the heart of our quest to understand the world around us. Although it's often hard to pinpoint everyday impact of this and related research, it is undoubtedly the case that it forms a vital piece of the puzzle of where we came from and where we're going.

[1] Rosetta 1: https://guidebook.com/guide/26449/event/9876531/

[2] Rosetta 2 / Comet Coma Chemistry and Nuclear Outbursts: https://guidebook.com/guide/26449/event/9876560/

[3] Hot Facts About Cool Comets: https://guidebook.com/guide/26449/event/9876955/

[4] Comets K1 (PanStarrs) and A1 (Siding Spring): https://guidebook.com/guide/26449/event/9876530/

[5] Sun-grazing Comet ISON: https://guidebook.com/guide/26449/event/9876567/

[6] Comet Dust, Tails, Trails, and Oddballs: https://guidebook.com/guide/26449/event/9876561/

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johndevor11y ago· 3 in thread

Could you speak more on the "everyday impact" about this landing? I'm trying to understand why this was worth the billion euros. It's seriously cool but that's all anybody seems to be saying. How does this really affect us?

ngoldbaum11y ago

Let's say a comet is going to impact Earth in a few decades. One proposal among many [0] to divert a comet is to aim a laser at it for a few years, long enough for the outgassing from the laser spot to push the comet onto an orbit that misses the Earth.

If you were designing a mission like that, wouldn't you want to have first-hand knowledge about the comet's surface?

This is also a baby step. We now feel more confident about landing equipment on irregularly shaped, rapidly spinning objects with negligible gravitational fields. Conservative estimates about the aggregate value of all of the rare heavy metals available inside a near-earth asteroid go into the trillions of dollars.

[0] http://www.lpl.arizona.edu/~jmelosh/HazardsDeflect.pdf

Cthulhu_11y ago

I think your latter point (about the value of asteroids) will have a much larger impact on the world and spacefaring in general than, say, observations about the temperature of an asteroid. If it turns out there's trillions worth of materials in asteroids, then I can guarantee the world's budget for spacefaring will go up a hundredfold within a few years.

Going to space for science (or beating the Russians) is one thing, going there for profit is a completely different matter and will attract heavy investors.

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johndevor11y ago

>Let's say a comet is going to impact Earth in a few decades.

You can't just make up stuff like this... sure, it could happen but you have to go off probability. What's the probability an asteroid will end all life on earth in the next thousand years? I'd guess not very likely.

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