Talk:1036 Ganymed

Latest comment: 8 years ago by Tamfang in topic orbit diagram

How big is 1036 Ganymed?

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This article says about 34 km; the article Near-Earth object, which links to this article, says ~32 kilometers.--Richardson mcphillips (talk) 00:20, 2 June 2013 (UTC)Reply

The JPL database (reference 2) says ~32 km, but Carry (2012) (reference 1) says ~34 km. --JorisvS (talk) 10:27, 2 June 2013 (UTC)Reply

mass/density

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7.9 g/cm3 seems too high. Pure iron has 7.89 g/cm3. However, S-type asteroids consist mainly of iron- and magnesium-silicates. Olivine is a magnesium iron silicate with the formula (Mg+2, Fe+2)2SiO4 with 3,2 bis 4,4 g/cm3 (without voids).

https://de.wikipedia.org/wiki/%281036%29_Ganymed claims 1,93 g/cm³ (without source). Some sources use an average density of 2600 kg/m3 when estimating asteroid mass, including 1036 Ganymed:

http://books.google.at/books?id=_PwVAgAAQBAJ&pg=PA80&lpg=PA80&dq=1036+Ganymed+density&source=bl&ots=QRqlQSRQ1E&sig=tXsPJMWcXVCouGSiZ8Th4Fil7h4&hl=en&sa=X&ei=oH4sVIO5IsvcaMubgJAN&ved=0CCQQ6AEwAjgK#v=onepage&q=1036%20Ganymed%20density&f=false

http://books.google.at/books?id=BWBGAAAAQBAJ&pg=PA593&lpg=PA593&dq=1036+Ganymed+density&source=bl&ots=ZVy6-SXaHT&sig=BmOWCU0IryaY5jfwjVi4wdGjXDI&hl=en&sa=X&ei=oH4sVIO5IsvcaMubgJAN&ved=0CB4Q6AEwADgK#v=onepage&q=1036%20Ganymed%20density&f=false

From the diameter and mass I even get 10 g/cm3.

In table 1 the source (https://arxiv.org/abs/1203.4336) has marked the density estimate of 1036 Ganymed as unrealistic. What's the meaning of mass=(1.67 ± 3.18) × 10^17 kg? Certainly the asteroid doesn't have negative mass.

I'm deleting

| mass=(1.67 ± 3.18) × 1017 kg
| density=7.9 g/cm3
| surface_grav=0.0089 m/s²
| escape_velocity=0.0168 km/s

Darsie42 (talk) 22:49, 1 October 2014 (UTC)Reply

Although well-sourced, without the error bars that value would be misleading: The source gives 7.91 ± 15.10 kg/dm3. In other words, the density has been studied and could be basically anything with the current data. It would be good to say something about this in the article, though this seems no good for the infobox. --JorisvS (talk) 08:13, 2 October 2014 (UTC)Reply

orbit diagram

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In the animated diagram, perihelion is not on the long axis of the ellipse! —Tamfang (talk) 07:47, 26 September 2016 (UTC)Reply