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Science: Footprints, Tardigrades, Amber, and more

By Bob Snodgrass
Posted: 10/27/2021

Present:  Barbara, Dick, Sally C, Sally A, Howard, Sue K in a reportorial role, Bruce, Bob

We had a pleasant meeting as usual. Barbara gave the first presentation about human footprints in White Sands, NM that appear to be about 23,000 years old. She gave a thorough discussion about the many preserved footprints there and the complex measures needed to determine their age. Determining the age of the soil in which the footprints are embedded doesn’t help. These footprints were found in White Sands National Park by a Park Manager. Research geologists at the United States Geological Survey were brought in to determine the age of the footprints. They dug a trench alongside the footprints and found human and animal footprints in 6 layers of sediment interspersed with eleven layers of ditch grass seeds. They collected the seeds and determined their age, The lowest layer with human footprints were just below a seed layer almost 23,000 years old.

 

These findings suggest humans in North America long before the Clovis people, a culture whose oldest artefacts are about 13,000 years old. Conventional wisdom has been that a land bridge (Beringia) developed across the Bering Straits at the end of the last Ice Age. The footprints suggest that humans arrived during the last Ice Age, before the existence of any known land bridge.

 

Howard showed pictures of tardigrades embedded in amber 16 million years ago. We’ve had some previous discussions of tardigrades because they are so tough and resilient. Tardigrades are very small aquatic invertebrates belonging to their own phylum, tardigrade. Arthropods are their closet relative. Most tardigrades are about 0.5mm long as adults. They were first discovered in 1773 and are found on every continent and in the deep sea. They can withstand temperatures from -450F to 300 F for several minutes. Because of their small size, they wouldn’t be identified in amber without using magnification.

 

Amber is fossilized tree resin, a sticky, viscous substance secreted by plants in order to protect them from pests and predators. And because it is meant to protect a plant from predators, sometimes those organisms get stuck in the resin and frozen for millions of years, preserving fragile structures and unique behaviors. I’ll just mentioned 99 million year old fossil ants found in Burmese amber. Eleven new species of ants were found in this amber.

 

Sally A next reported on the Perseverance rover, which has now been able to drill out some samples and stored them in a titanium tube, to be picked up from Mars and returned to earth at a later date. Its first attempt to collect sample in August was unsuccessful because it drilled into a soft rock. She also spoke about the James Webb telescope, which has now gone through the Panama canal and arrived in French Guiana. It is the largest, most powerful space telescope ever built, and cost $10 billion. It will allow scientists to look at what our universe was like about 200 million years after the Big Bang. The telescope will be able to capture images of some of the first galaxies ever formed. It will also be able to observe objects in our solar system from Mars outward, look inside dust clouds to see where new stars and planets are forming and examine the atmospheres of planets orbiting other stars. Its planned launch date is December 18. There is a European Space Agency launch facility at Kourou. The James Webb telescope is a joint NASA, ESA, and Canadian Space Agency program.

 

The Webb telescope is as tall as a 3-story building and as long as a tennis court. It is so big that it has to fold origami-style to fit inside the rocket to launch. The telescope will unfold, sunshield first, once in space. Infrared cameras will see through dust in our universe. Stars and planets form inside those dust clouds, so looking inside might produce new discoveries. It will also be able to see objects (like the first galaxies) that are so far away that the expansion of the universe has made their light shift from visible to infrared (extreme red shift).

 

Howard reported that Pittsburg is the first US city to pass laws to control nocturnal light pollution. The Pittsburgh City Council just passed a new Dark Sky Ordinance for all of the city’s parks, facilities and streetlights. Pittsburgh had terrible light and air pollution 100 years ago but has gradual cleaned up its air.
The city will retrofit existing streetlights to dark sky compliant LED lights. Pittsburgh’s current 4,300 LED streetlights glow at 5,000 kelvins and give off a bright blue-white glare. The new LED lights will be at a lower temperature and look much softer and warmer.

 

Bob reported on the KISS lecture on interstellar objects on September. KISS comes from Keck Institute for Space Studies, which has a series of monthly lectures. This one, Interstellar Comets – Visitors from Another Solar System – Natural or Artificial? Was given by Dr. Karen Meech University of Hawai’i. I enjoyed it. We’ve only had 2 conformed interstellar objects pass through our solar system, although there is reason to be believe that some objects within the Solar System came from outside. The big splash came in October 2017 when Oumuamua was spotted by the Hawaii Panoramic Survey Telescope and Rapid Response System. You’ve all seen the image below, but it’s not a photograph, just an artist’s impression from the early days of observation. Oumuamua has a long axis and was tumbling in a very complex way. More recent consideration of its very complex motion has suggestion a different image.

 

We really don’t know because it passed through the solar system so quickly. It was soon out of the solar system and unavailable for further observation. The second ISO, named Borisov after the amateur astronomer who first reported it, had very high carbon monoxide content and also came from outside the plane of the ecliptic. The two ISOs came from different regions of the universe. Astronomers hope to have an orbiting system (The ESA Comet Interceptor and/or the NASA iBridge n place by 2029 that could be dispatched to closely study and perhaps take a piece of any future interstellar objects that may appear.

 

Bruce also reported seeing the introduction of fiberoptic cables into LA County years ago. Fiberoptics have many advantages over standard cable connections.

 

Please remember that we have an outside speaker for November 8^th, Dr. John Mulchaey of the Carnegie Observatories- the telescopes and other instruments are far from Pasadena these days, but analysis and planning are still here.  Howard arranged this – we’ll get out more advance publicity.