Show notes for the 21st of October 2013
Hosts: Ryan, Hugh, Pat
Title: Coming Full Circle
This week in space/astronomy history:
1. October 23, 2013 – Planck satellite shuts off forever! Today (Oct. 21), ESA ordered Planck to run its thrusters to empty. After years hovering at a Lagrange point, the telescope will be put in a ‘parking orbit’ to circle the sun, keeping it away from the Earth and moon for at least several centuries. The last command will be sent Oct. 23. Among other milestones, Planck released a cosmic map in March refining the Universe’s age to 13.82 billion years. (Suggested Reading: Universe Today article)
2. October 24, 1946 – The first photo of Earth from space was taken. The black-and-white photos were taken from an altitude of 65 miles (104 km), above the commonly accepted boundary of space at 100 kilometres, by a 35-millimeter motion picture camera on a V-2 missile launched from the White Sands Missile Range. The rocket-borne camera climbed straight up, then fell back to Earth … the camera itself was smashed, but the film, protected in a steel cassette, was unharmed. (Suggested Reading: Air & Space)
3. October 1923 – First public planetarium show, Deutsches Museum in Munich
4. October 22, 1905 – Karl Jansky born, father of radio astronomy
5. October 22, 2136 BC – The first documented solar eclipse. Two astronomers in ancient China (astrologers, back then) were beheaded for failing to predict a solar eclipse (they were too fond of drink, hence they are informally known as Hi & Ho the drunk astronomers). Identifications of this event have varied from 2165 – 1948 BCE, though the favoured date is October 22, 2137 BCE. The emperor became very unhappy because, without knowing that there was an eclipse coming, he was unable to organize teams to beat drums and shoot arrows in the air to frighten away the invisible dragon. (Suggested Reading: Astronomy Today article)
1. Curiosity Corner with Ryan Marciniak. The curiosity rover is still trekking along and throwing in a bit of awesome science like its nobody’s business. By looking at the ratio of Argon 36 to Argon 38 in the Martian atmosphere, Curiosity has given Earthlocked scientists a definitive test of the origin of meteorites, proving whether or not they originated on Mars. On Mars the light to heavy ratio of Argon is skewed lower due to Mars losing most of its original atmosphere to space. Lighter Argon has a lower escape velocity and was lost to space, leaving heavier argon to dominate. The Sample analysis at Mars instrument has nailed the number down to 4.2 argon 38 atoms for every Argon 36 atom. By looking at gas bubbles in meteorites and comparing the ratio found to that of Mars, we can verify which meteorites came from Mars. Also a good note is that because Argon is inert (not reacting with other elements), its ratio is a true indicator of the amount of Martian atmosphere that has been lost to space.
In the meantime, India will be sending ‘MOM’ to watch out for Curiosity. The Mars Orbiter Mission is slated to launch on October 28th, from Srihanikota, India. This will pave the way for bolder Martian missions by the Indian Space Research Organization (ISRO), and will make India the 4th nation to survey the red planet up close. The main objective of the orbiter is to seek out Methane and study the atmosphere, morphology, and mineralogy of Mars. (Suggested Reading: NASA Curiosity Mission Page, Universe Today article)
2. Asteroid discovered that will NOT hit the Earth! (with 99.998% probability). Asteroid 2013 TV135 currently has a 1 in 63,000 chance of hitting Earth in 2032. The asteroid is estimated to be about 1,300 feet (400 meters) across. It orbits the Sun once every four years, getting out to three quarters of the distance to Jupiter’s orbit and as close to the sun as Earth’s orbit. It was discovered on Oct. 8, by astronomers working at the Crimean Astrophysical Observatory in Ukraine. It is one of just over 10,000 near-Earth objects that have been discovered.
Asteroids are discovered as moving objects in a series of still photos. As more photos are taken, the orbit can be determined. That’s where this object stands now; it has less than 2 weeks’ worth of observations. As even more photos are taken, its orbit will be pinned down more precisely, and the chances of it hitting early will almost certainly decrease.
Two Canadians (and others) have a proposal to help catalog PHAs that haven’t been found yet: PHASST. http://phastt.net/
You can help crowdfund their plan to install two telescopes in Spain and Peru to search for PHAs. They are designing PHASTT-1 as not only a search telescope but also as a followup and characterization instrument — two key areas where [they] can make an impact,(Suggested Reading: Universe Today article, NEOWISE)
3. ‘Star Axis’ in New Mexico. Artist Charles Ross (wife Jill O’Bryan) well known for his work with light and with prisms. Star Axis is all about axial precession (discovered by Hipparchus of Rhodes in 2nd century BC); it allows you to explore the way the sky would have looked years and years ago and how it will look in the future. Ross has spent 40+ years on it! The idea for Star Axis came (1971) when Ross was looking at a schematic of the celestial alignment of the Pyramids of egypt. It turns out that the eastern and western sides of the pyramid are aligned directly along the north south axis, but that if you arrange their angles against true north in chronological order of their construction then you notice that they are all slowly turning clockwise, indicating that their method of orientation was vulnerable to precession. In fact we think that the star that they were following to construct these pyramids was 10i Draconis.
Star Axis is a 10 storey staircase starting in the middle of a man made basin below the desert floor and ascending to a triangular formation a few metres above the desert floor. At the bottom of the staircase the stairs are open to the sky, but at the pyramid structure at the end of the staircase the staircase follows a hole that has been bored in the rock resembling a tunnel through the Earth’s core, or even just a telescope made out of the Earth. Standing at the bottom of the staircase the tunnel is about the size of a dime held at arm’s length, and all you can see is Polaris making its tiny orbit. As you ascend the stairs the circle in your vision gets larger (imagine bringing the dime closer to your face) representing the celestial path of Polaris as earth’s precession takes us further and further away from the current polar star. Third step = year 2100, when Polaris is the closest to the centre of the pole (and the tunnel!). Top stair = 13,000 years into the future (or 11,000 BC) when Polaris will be at its widest orbit (163 steps total). (Suggested Reading: On the Pyramids, Aeon Magazine spotlight)
Thanks for listening!
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