Some Important Information before we start:
• This an EarthCache and there is NOT a physical container here. To log this cache, you first need to visit the location and answer the questions at the bottom of this page relating to the information you find there.
• I accept answers for this EarthCache via email or by Private Messaging and will endeavour to reply to all queries within a few days. Please do NOT post your answers in your log, or I'll delete it. Also, answers must be submitted within 7 days of the log - no answers after 7 days will result in me deleting your log!! Pictures are completely fine in your logs though :)
• This EarthCache is located at the Otford Recreation Ground, High Street, Otford, Kent, TN14 5PG. A couple words of warning, the Otford Solar System model http://www.solarsystem.otford.info/ , which is probably the largest scale model in the world, is located in a playing field. Thus when attempting this cache on the weekend, sport games could be occurring and when walking to the centre of the solar system model, be careful that you don’t step on Mars…...
Now, onto your lesson for today…
Impacts by asteroids and comets can create cataclysmic events that destroy life and have had a significant impact (no pun intended) on both the Palaeontological and geological record. Many Earth scientists believe that the Permo-Triassic mass extinction, which occurred between 290 and 252 million years ago, and which saw the extinction of 95% of all marine life and 70% of all land species was the result of a meteorite impact. The age of the dinosaurs ended 65 Million years ago when a meteorite at least 10 km (6 mi) in diameter impacted near present day Mexico, forming the 180 kilometre (110 mi) diameter Chicxulub crater and dooming the dinosaurs to extinction. Scientists believe such devastating “Extinction Event” meteorite impacts occur every 100 million years or so. These events would happen much more frequently without the Earth being protected by the other planets in the solar system. Without Jupiter, for example, instead of being hit with a killer asteroid every hundred million years or so, the Earth would be impacted every 10,000 years. This reduction in impacts enabled the Earth to develop both simple and complex forms of life. Jupiter is the 5th planet from the Sun in our solar system as well as the largest and is also known as a gas giant. Jupiter is composed of a solid core of iron and silicon with the rest mainly composed of hydrogen and to a lesser extent helium. Jupiter is about 2.5 times the mass of all the other planets in the solar system. But gas giant planets like Jupiter don’t always help. Whilst Jupiter deflects many asteroids away from Earth, it also is responsible for most of the asteroids in the first place. When planetesimals were clumping together to form the terrestrial planets, the gravitational influence of Jupiter prevented a fifth planet from forming. Today there is an asteroid belt that lies between Mars and Jupiter and this asteroid belt is a sad echo of the planet-that-never-was. Mars was also affected by Jupiter’s gravity whilst it was forming. Mars is only half the size and one-tenth the mass of Earth, prevented by Jupiter from accumulating enough mass to become an Earth-like world capable of sustaining complex life. The lower mass of Mars, in combination with its low magnetism, prevented the planet from retaining an atmosphere a vital necessity for life to exist and thrive. An astronomical unit (abbreviated as AU, au, a.u., or sometimes ua) is a unit of length equal to about 149,597,871 kilometres (92,955,807 miles). It is defined by the International Astronomical Union, and is defined as the mean distance between the Earth and the Sun over one Earth orbit.
To claim this Earthcache several tasks need to be completed:
Task 1 – How long does it take you to walk or run from the Sun to the Earth? On average, light takes roughly 8.3168708 minutes to travel 1 AU (but who's counting...). If it takes you 10 seconds, then you’ll be travelling at approximately 50 times the speed of light.
Task 2 – Once you’ve reached the Earth, take a photograph from the position of the model Earth showing the model ‘Sun’ (optional).
Task 3 – There is an asteroid belt which rotates around the Sun between Jupiter and Mars. Sometimes the asteroids can come as close as 643,600 km (400,000 miles or 0.0043 AU) to the Earth and the Sun. What distance does this equal in the model?
Task 4 – Jupiter is a distance of approximately about 5 AU from the sun. What are the GPS coordinates of the Jupiter pillar and using your GPSr what direction is the Sun in relation to Jupiter?
Anyway hope you enjoyed this cache! :)