"asteroid started the last ice age"
Just so you won't have to appear dumb on any thread but this one,
A summary of the sequence of events for the last 130,000 years ('real' years);
Phases about as warm or warmer than the present are marked in bold.
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150,000 y.a. - cold, dry full glacial world
around 130,000 y.a. - rapid warming initiates the Eemian interglacial (Stage 5e)
130,000-110,000 y.a. - global climates generally warmer and moister than present, but with progressive cooling to temperatures more similar to present.
(except for possible global cold, dry event at 121,000 y.a.)
?110,000 y.a. - a strong cooling marks the end of the Eemian interglacial (Stage 5e).
105,000-95,000 y.a. - climate warms slightly but still cooler and drier than present; strong fluctuations.
95,000 - 93,000 y.a. - another cooler phase similar to that at 110,000 y.a.
93,000 - 75,000 y.a. - a milder phase, resembling that at 105,000-95,000 y.a.
75,000 - 60,000 y.a. - full glacial world, cold and dry (the 'Lower Pleniglacial' or Stage 4)
60,000 - 25,000 y.a. - 'middling phase' of highly unstable but generally cooler and drier-than-present conditions (Stage 3)
25,000 - 15,000 y.a. - full glacial world, cold and dry; Stage 2 (includes the 'Last Glacial Maximum')
(This period includes two 'coldest phases' - Heinrich Events - at around 23,000-21,000 y.a. and at 17,000-14,500 y.a.)
14,500 y.a. - rapid warming and moistening of climates in some areas. Rapid deglaciation begins.
13,500 y.a. - nearly all areas with climates at least as warm and moist as today's
12,800 y.a. (+/- 200 years)- rapid onset of cool, dry Younger Dryas in many areas
11,500 y.a. (+/- 200 years) - Younger Dryas ends suddenly, back to warmth and moist climates (Holocene, or Stage 1)
9,000 y.a. - 8,200 y.a. - climates warmer and often moister than today's
about 8,200 y.a. - sudden cool and dry phase in many areas
8,000-4,500 y.a. - climates somewhat warmer and moister than today's
Since 4,500 y.a. - climates fairly similar to the present
(except; about 2600 y.a. - relatively wet/cold event (of unknown duration) in many areas)
esd.ornl.gov
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You probably heard some adults talking about this and got confused...
news.nationalgeographic.com
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