As a working astronomer, the two things I get asked about most are whether I believe in extraterrestrial life and whether I think an asteroid is going to hit the Earth any time soon. My field of expertise is galaxy formation, which mostly happened billions of year before the Earth was even formed and studies objects so large that our entire solar system would be a mere drop of water in the sea of trillions of other drops that the typical galaxy holds. I have no formal biology training above high school and the study of the solar system is almost a different branch of science altogether, more often thrown in with the "Planetary Sciences" rather than traditional astronomers. Still, apparently I am the the man to ask these Earth shattering (literally) questions, because if the government was hiding something I clearly have to be on the inside track, because, well, I regularly use telescopes. Or maybe because I get NASA money? It is not like my funding comes with a conspiracy mailing list or anything...
For future reference, my stock answers are:
A) No one has any idea whether there is any other intelligent life out there. You can't make an extrapolation from a single data point, by which I mean us. If smart aliens were so rare as to be only created once per galaxy... then that would have to be us, wouldn't it? Aesthetically I find the notion of us being the only ones displeasing, but I have no scientific reason to say otherwise. I do not buy into the notion that if they existed they would have visited us by now (I do not believe they have. The bright light you saw was probably just Venus). The galaxy is a big place and making any assumptions about a lifeform which might not even breath the same air we do seems a bit audacious.
B) Killer asteroids do hit the Earth. However, these dinosaur-killers only come once ever 50-100 million years or so. I would not put it at the top of my list of things to worry about, but I would spend a modest amount of time and money tracking asteroids. Whatever particular asteroid that you recently heard about striking the Earth is almost certainly NOT going to strike the Earth. Measuring the orbits of tiny celestial bodies is exceedingly difficult. Virtually every "this asteroid will hit the Earth in 2163" story you have ever read was based on the initial measurement of its future path. This measurement has a gigantic error associated with it. If the Earth fits inside the error, that is usually good enough for a press release and associated hoopla. Later measurements shrink the error bars. Odds are strongly in favor of the Earth falling outside those recalculated error bars.
Still, scientists love fame and media attention as much as the next guy, so I would not expect an end to these stories about Earth killing asteroids. Apparently a lot of them can be blamed on a single asteroid-asteroid collision 160 million years ago, possibly even the asteroid that led to the extinction of the dinosaurs. This mega-crackup out in the asteroid belt created a whole mess of giant asteroids, now referred to as the Baptistina family, making the killing of the dinosaurs the most spectacular mob hit of all time.
The astute among you might note that the creation of the 120 mile diameter Chicxulub crater in the Yucatan that is now closely associated with what Tyrannosaurs of the time thought of as a "real bummer of a day", was created 65 million years ago, not the 160 million BC date that the Baptistina rock crash occurred. The overachievers among you would go on to point out that 160 million years is actually the middle of the Jurassic period, while the K-T boundry isn't until the end of Cretacious, which means we are talking Allosaurs not T-rex!
Yeah, well you poindexters can spend an extra hour in study hall pushing your glasses back on your noses and snorting milk out your nose....
Whoah, where did that come from? I must have some repressed rage against paleontologists. Or maybe it was just those those lame Jurassic Park movies. Anyway, the point was there was a doubling in the number of rogue asteroids (which is determined from cratering rates) in the time period of 50-150 million years ago, which the authors of the study trace to this Baptistina incident. So if half of all Earth-crossing asteroids at the time of dinosaurs still came from this ugly little asteroid billiards break, that would make a 50% chance it was one of them that did in the dinosaurs. Looking at the type of asteroid that made the Chicxulub crater the authors determined that it matched the Baptistina family (Dammit Louie, you got to make sure you whipe your gun before dropping it!), making the odds more like 90%. For good measure the authors throw in the Tycho Crater on the moon, which was also formed around the same time. I need only point out that this is also the location of the Monolith discovered in 2001: A Space Oddysey to bring this whole intro full circle.
No house updates this entry. House remodels are exhausting and I just want to have some fun and go to the zoo. The San Diego Zoo to be precise. Here we are on a sunny August day at the zoo's entrance, where I believe I have just had my hat impaled by a topiary elephant. A young hooligan asked me for change, so I grabbed him and would have given him a proper thrashing if his parents hadn't been the ones taking this photo.
OK, in actuality the boy is Ian, the son of our friends Kris and Jenny whom we stayed with in San Diego. Other clear fallacies: there are no hooligans in San Diego and the boy asked not for a bit of change, but for my entire wallet. The only thrashing received was me from the damn topiary, which refused to move out of my way no matter how much I beat at it and screamed "Move Bush!" at the top of my lungs. Did I mention it was hot? That I suffered from some mild heat-related hallucinations? That the topiary elephant later apologized and joined me in the gazebo for a crumpet and a spot of tea?
Smashing.
This slightly dark and blurry photo was taken from the security camera in the reptile house, where this miscreant was discovered try to feed a baby to a giant Monitor lizard. Fortunately I caught him in the act and kept the poor child from being lizard chow.
The reptile house was our first stop on the zoo tour, at the insistence of young Ian. Kayla was deep asleep at the time, so Rylie got the Daddy shoulder tour. Unfortunately most reptiles are not big movers, so even impressive monsters like this monitor lizard did not get a lot of interest from the baby. One exception was a giant 20+ foot python, who came up and licked the glass right next to Rylie's head. The two of them just sort of stared at each other. I am proud to say that it was the python that eventually gave way. Beware staring into the eyes of a baby. They can mesmerize you.
By the end of the day it was Rylie who was konked out in the stroller and Kayla who got the front row seat. Her absolute favorite were the elephants. The San Diego Zoo has three, two African and one Indian. I assume there is a joke there, but I am sure it is in bad taste. Here is one of the African elephants giving himself a shower with its trunk.
This is Kayla going nuts at the sight of the elephant. You can't quite see her eyes, but I think her mouth expresses it all. I can only imagine she was thinking that she had never seen such a big dog before. The elephant then picked up a magic feather and flew away by flapping its giant ears. Crows could be heard laughing and soon after we saw a peanut stand, a rubber band, and a needle that winked its eye.
The San Diego Zoo is famous for its Panda denizens and they had in fact recently given birth to another tiny, rat-looking baby, so the exhibit was packed. Pandas seem to me to be the clearest evidence of God, as no way could any creature have evolved into such a precarious state. For starters, Pandas eat nothing but a certain type of bamboo. However, the digestive tract of the Panda is not well designed to actually absorb nutrients from bamboo, requiring the Panda to spend every waking moment eating so that it might glean just enough calories to stay alive.
Pandas also are not big fans of mating, even in the wild. Panda bears are generally solitary creatures, who mark out gigantic bamboo forest territories for themselves, which they have to do, if you recall, because of the insane amounts of bamboo they must eat just to survive. This makes male/female encounters rare in the first place. If they do find each other, it is very common that the female spurns the male's advances. Fine and good -- who wants three hundred pounds of horny bear on top of them -- but the species is dying out for crissakes. The females are not being picky, they are comitting species suicide. Finally, if a female does get pregnant, the baby it gives birth is so ridiculously small and helpless that the mother will occasionally just roll on top of it by accident, crushing it to death.
Seriously, should such a maladapted creature really continue to live? I guess they do fill that valuable cuddly/cute niche. Where people are concerned, that is definitely a survival trait.
Finally, here are a couple of meerkats. One is an actual African meerkat, famous for their Manors and close friendships with warthogs. The other is a spokesmeerkat for the park and should in no way be associated with or be compared to the Disney character Timon for the Lion King. Totally different and non-litigatable. I will leave it to you to tell which is which, but I will drop you the hint that real meerkats are not big on tickling babies.
Or polyester blends that smell suspicously of stale sweat.
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