Sep
21
2008
0

Solar System’s Fifth Dwarf Planet Named

On September 17, the International Astronomical Union announced that 2003 EL61 would be classified as the fifth named dwarf planet and officially designated Haumea. The name was chosen after meetings of the IAU’s Committee on Small Body Nomenclature and the Working Group for Planetary System Nomenclature. The number of dwarf planets is now five: Ceres, Eris, Haumea, Makemake and Pluto.

The 2,200 km ellipsoidal body—deformed due to a four-hour rotation period—is just beyond the orbit of Pluto and has two satellites. Orbiting among the Trans-Neptunian objects, Haumea is currently 50 astronomical units from the Sun but can get as close as 35 A.U. The astronomical unit is the average Earth-Sun distance and a standard measure of distance within the solar system.

In Hawaiian mythology, Haumea is the goddess of childbirth and fertility.

Written by Brent in: Space Exploration | Tags: , , , ,
Sep
16
2008
1

Shine on, Shine on Harvest Moon

At 4:13 a.m. CDT the Full Moon of occurred. Being the Full Moon nearest the autumnal equinox, which occurs at 10:44 a.m. CDT on September 22, this Full Moon is traditionally called the Harvest Moon. So what is so special about this particular Full Moon, which can occur any time from mid-September to early October? Typically the Moon rises about 50 minutes later each day due to its slow eastward (prograde) drift across the star field, but around the time of the autumnal equinox that time is reduced to about 22 minutes.

The reason for this difference is the smaller angle between the ecliptic—or apparent path of the Sun across the sky—at this time of year and the Moon’s orbital path in addition to the narrow angle the Moon’s orbital path makes with the horizon. Given this particular geometry, there are fewer minutes between sunset and moonrise on the successive nights. More hours of bright moonlight on these evenings meant extra time for the farmers working outside to finish the harvest.

References: Some names of the Full Moons.

Written by Brent in: Calendars, Time | Tags:
Sep
10
2008
0

Large Hadron Collider Taken for a Spin

The beam line of the Large Hadron Collider

Early this morning physicists at the CERN—the European Center for Nuclear Research that straddles the French–Swiss border—activated the world’s most powerful particle accelerator. After a quarter century of dreaming and nearly 15 years of construction, several beams of protons were sent through the 17-mile beam ring that is buried 300 feet below the shores of Lake Geneva. Today’s test is a crucial first step on the path leading scientists to the unimaginably energy a mere trillionth of a second after the Big Bang. Eventually counter-circulating beams of protons (the proton is one member of a class of particles called hadrons) will collide to recreate those conditions.

In order to recreate those exotic conditions, the beams of protons must be accelerated to within a tiny fraction of the speed of light. Because Einstein’s special theory of relativity dictates that an object gains mass as its velocity increases (a hypothesis that has been experimentally verified time and time again) and also that mass and energy are equivalent. Thus, extremely high velocities are needed to produce the energies needed to test our theories of the early universe and the fundamental nature of mass itself. The LHC is expected to eventually accelerate protons to energies of 7 trillion electron-volts (7 TeV) where each electron-volt is the kinetic energy gained by a single electron as it moves through an electric field of 1 volt. The eV is the fundamental unit of energy used in nuclear physics.

By recreating conditions shortly after the Big Bang, physicists hope to glimpse evidence of the Higgs boson—a particle hypothesized to exist in those rarified conditions that is responsible for giving the property of mass, and thus inertia, to matter—as well as learn more about the elusive dark matter that accounts for anomalies in the rotation rates of galaxies and holds clusters of galaxies together. Dark matter is thought to account for as much as a quarter of the matter in the universe. One thing that the LHC is not expected to produce is an Earth-swallowing black hole. While “mini” black holes that are sub-atomic in size may be produced, if in fact they exist at all, the production of black holes that would spell doom for the earth is the stuff of fiction not science. No credible scientific evidence predicts that sort of scenario. In fact, Earth’s upper atmosphere is bombarded by cosmic rays of even greater energy every day and no mini black holes have been observed in those collisions.

One thing that is inescapable, however, is the bittersweet moment the test firing of the Large Hadron Collider represents. Even though the LHC is an international effort, the United States has relinquished its position as a leader in basic high-energy physics. Construction of the Superconducting Supercollider in Texas ended in 1993 when Congress looked for ways to save money and eliminated the funding after $2 billion dollars had already been spent. The SSC was to be an even bigger project than the Large Hadron Collider, whose construction was undertaken the year after the Superconducting Supercollider was killed. Although its budget eventually ballooned to $11 before being defunded, the SSC represented a mere 0.6% of the federal R&D budget for FY1992.

Given the politically-charged environment in which basic scientific research must be conducted today, CERN’s approach, with over 20 countries providing funding that is governed by treaty, may be the reality for the foreseeable future. Gone are the days of national pride in scientific achievement like those when physicist Robert Wilson was asked in a congressional hearing about the proposed FermiLab’s benefit to the United States’ national security. His reply: “It has nothing to do directly with defending this country except to make it worth defending.”

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