Many years ago I was contacted by a German researcher who told me I am a descendant of 40 odd skeletons found in the Lichenstein Hole (a family tomb in a sealed cave) dating from 2500 years ago. They found another descendant less than 5kms from that cave. They were thought to have been Visigoths or Frisians.

I have read that some 60% of English people can find Edward the Confessor in their lineage - and even slightly more French can find Charlemagne in theirs. We're all related anyway - Mitochondrial Eve.

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Also: three of those grandparents could also be children of Genghis Khan.

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Meteorites entering the atmosphere don't burn, it's an entirely different and quite complex process.

The high energies and temperatures involved creates dense a plasma surrounding the meteorite composed of excited (electrically charged) molecules, ionised air plasma and ionized meteorite plasma, with temperatures between 2,700 - 50,000 kelvin (some sources say up to 100,000 kelvin).

Magnesium plasma (singly ionized magnesium) in particular is responsible for the green color of some meteors, ionized magnesium (Mg I) emits green light between 517-518 nm.

The Peekskill meteorite created a noticebly green fireball, it was a H6 stony iron condrite (containing orthopyroxene with 17% magnesium).

Other emission lines include ionised iron (blue emission lines) and sodium (yellow-orange emission line), as well as innumerable emission lines from aluminum, calcium, chromium, hydrogen, nickel, silicon, and manganese. These many emission lines merge to form a continuous spectrum (white meteors).

The relative contribution of the main emission lines of iron, magnesium and sodium control the color of meteors, which emission (colour) predominates is related to the meteor's composition and velocity; fast meteors (>30 km per second) ionize magnesium and are green, moderate velocity meteors (30-15km per second) ionize iron and are blue, and slow moving meteors (<15km per second) ionize sodium and are yellow-orange.

Atmospheric air is also ionized at the very high high temperatures involved. Emissions lines from nitrogen, oxygen, and nitrogen oxides are also detected. These are responsible for Persistent Trains, a long lasting dim afterglow of a fireball that can last a few seconds to minutes.

>Subsequent air collisions are predominantly with the vapor cloud (Padevet, 1977), causing atomization and ionization of meteoric vapor and air molecules. In this process, impact excitation, leads to much of the observed optical emission of meteors (Öpik, 1955, 1958).

There's also black body emission from cooling meteoric dust.

Ref.:

Jenniskens, P., 2004. Meteor induced chemistry, ablation products, and dust in the middle and upper atmosphere from optical spectroscopy of meteors. Advances in Space Research, 33(9), pp.1444-1454.

Taylor, M., Gardner, L., Murray, I. and Jenniskens, P., 2002. Jet-like structures in Mg (518 nm) images of 1999 Leonid storm meteors. In 34th COSPAR Scientific Assembly (Vol. 34, p. 2917).

Edit: Here's a book from the late 1950s about the physics of meteors...

Physics of meteor flight in the atmosphere by Ernst Julius Opik

The most important consideration is the D antigen aka Rh antigen which doesn't affect the first pregnancy, as others have said. If mom is Rh- and dad is Rh+, there is a chance that the fetus is Rh+. During pregnancy and especially during childbirth or miscarriage, the mother and fetus exchange blood. Mom's body recognizes the fetus' Rh+ blood as foreign and generates antibodies against this factor. This won't affect the initial pregnancy. However, if mom gets pregnant again with an Rh+ baby, then the antibodies will cross the placenta and attack the baby's red blood cells, causing a disease called hemolytic disease of the newborn. Its a serious form of anemia that can kill the baby.

This is why Rh- moms are given Rhogam, an antibody against this antigen. The idea is that during that first pregnancy, the Rhogam will "hide" the Rh antigen from the mother's immune system, preventing the formation of those antibodies and protecting future pregnancies.

In general, canned goods stay good until the can itself is damaged (I.e dented, rusted, or otherwise leaking can). The “best or use by” date on the can is just an estimate by the manufacturer for how long it’ll be at peak freshness. If you have a use by 2028 on canned tomatoes that’s probably an estimate of when those tomatoes will have lost their texture and started developing “off” flavors.

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This may not be relevant, but I once calculated that at the 7th generation there is only a 50% chance of inheriting DNA from an ancestors. This is because DNA breaks are chunky and at a certain point you can just lose all the DNA from an ancestor . So when you go back you are actually only related to a subset of your ancestors

Interestingly 7 generations is also the max number of generations in a human lifetime for most people

• Great Grandpa
• Grandpa
• Father
• Me
• Daughter
• Granddaughter
• Great granddaughter

I've always wondered if this is fine tuned by our DNA crossings

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I've seen green meteorites a few times this year alone. They're not that uncommon.

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On the other hand, if you don't require every ancestor to be "unique", that is, not relatives by ancestry, but just want to know the number of unique persons who are ancestors, my simple formula isn't very helpful. If cousins marry and produce a grandchild, that grandchild has 2**3 - 2 great-grandparents instead of 2**3.

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If you are talking a small island (Guam) it would be much lower numbers.

If you are talking about Hollars in WV, it might only be 3-4 generations. The Hollar I am familiar with had 2nd cousins marrying and only about a dozen families in total.

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In general, everything /u/Synaps4 said. That being said, as most meteorites are made of a variety of atom types that probably have different ionization energies, my bet is that you would see white as a default - as is consistent with personal meteorite viewing experience.

For this picture, my bet is Photoshop.

They already knew that he was a descendant or at least related. The visual reconstruction, came after the DNA tests.

This is an optimistic estimate that casually ignores physical/cultural barrier and lack of movements. This estimate only applies if people move around often and for a long distance to leave descendants around a big area all over the world like in modern world which isnt really applicable to ancient past. I seriously doubt some native american living at that time is a common ancestor of most people living in eurasia right now.