It is now generally accepted in the astrophysics community that at the center of nearly all galaxies lays a super massive black hole. However, there exists a theory about black holes that could change that. The theory, derived from Einstein’s General Theory of Relativity, says that if two black holes were to merge, gravitational waves would fly out in one direction, kicking the black hole in the opposite direction like a recoil. The theory sounded interesting but no one had ever observed two black holes merging, let alone a black hole recoiling. The possibility of two massive black holes merging was also just theory, as you can imagine it’s hard to observe two invisible things crashing into each other.

Well a team from the Max Planck Institute for Extraterrestrial Physics (MPE) has, for the first time, witnessed these events. The team witnessed a recoiling black hole moving at a very high speed of 2650 kilometers per second! Because of the tremendous power of this recoiling effect the black hole was catapulted from its parent galaxy. The astronomers were able to track it by the gas, or accretion disk, moving with the black hole; and also by the excited gas that was left behind.

This new observation has many implications. It brings this process from the world of just theory to the world of actuality. It not only tells us that these “super kicks” happen but also that black holes do merge, and lends support to the theory of gravitational waves, which have yet to be directly observed. This also means that there are galaxies out there without a super massive black hole at the center. That fact raises questions about the role or dependence on the central black hole and galaxy formation. Is the black hole there at the start of the galaxy? Is it needed for the galaxy to evolve normally? And what effect does it have on the host galaxy when it looses its black hole?

Astrophysicists, observers and theorists alike, are invigorated to start trying to answer some of these questions. Both earth and space based telescopes will be set to try and detect more of these events, and work is being done to get gravitational wave detectors working. Theorists will also be getting going on more details of these types of events with the help of computer simulations. Weird to think there might be these super massive black holes just floating around out in between the galaxies, lurking there, possibly waiting for a future spacecraft to fly right in.

	LISTEN NOW: [audio:http://ourundiscovereduniverse.com/podcast/OUUpodcast_09012008.mp3]
	DOWNLOAD MP3 NOW: OUU Podcast #2: Black Holes: The nature and composition of black holes as well as the important role galactic vortices play in Null cosmology.

Welcome to the second in a series of podcasts that explore Null Physics as presented in the book, Our Undiscovered Universe, written by Scientist and Engineer, Terence Witt.

The topics of discussion include the nature and composition of black holes as well as the important role galactic vortices play in Null Cosmology.

Also in Episode 2:

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For a long time know we’ve thought that we had certain basics of stellar evolution figured out, but as always it seems in science once we think we know something a wrench gets thrown into the works. When a star dies one of three outcomes can happen. If the star is around or below about 8 solar masses, the star will die in a planetary nebula where it puffs off its outer layers and leaves behind a white dwarf star. If it is more massive than that about 8 solar masses the star will go supernova and leave behind a neutron star, or if massive enough a black hole. While both white dwarfs and neutron stars are both stellar remnants they are considered to be quite different objects.

A white dwarf is an inert stellar core left hot from the burning of the star but it is thought to gradually just cool off and after billions of years would become cold and dark, or a black dwarf. They are dense small objects, about the size of earth with the mass of the sun. But white dwarfs have never been particularly strange and bizarre, unlike neutron stars. Neutron stars are also small dense objects with masses of around 2 solar masses but packed inside the size of a city. Neutron stars are incredibly hot, made entirely of neutrons and supported against further collapse by the Pauli exclusion principle; which says no two neutrons can occupy the same quantum state. Neutron stars have very strong magnetic fields, and spin incredibly fast usually spinning several times to several hundred times per second. These strong magnetic fields combined with their very short period make them “pulse” due to particle acceleration near the magnetic poles. These pulsars produce streams of radio emission making them like beacons we are able to detect and even listen to.

New observations from a joint observatory between NASA and JAXA (Japanese Aeronautics Exploration Agency) have detected a white dwarf pulsar. AE Aquarii emits pulses of high-energy X-rays as it whirls around on its axis, and this is the first time pulsar like activity has been detected in a white dwarf. The hard x-rays match the star’s spin period of once every 33 seconds. The hard X-ray pulsations are very similar to those of the pulsar, or neutron star, in the center of the Crab Nebula. In both objects, the pulses appear to be radiated like a lighthouse beam, and a rotating magnetic field is thought to be controlling the beam. Astronomers think that the extremely powerful magnetic fields are trapping charged particles and then flinging them outward at near-light speed. When the particles interact with the magnetic field, they radiate X-rays.

No doubt after this discovery we may begin pointing our X-ray telescopes at more white dwarfs, or maybe even questioning some of the pulsars we’ve already identified as neutron stars. This may also have us questioning what we thought we knew about the death of low mass stars, as it doesn’t appear as peaceful a progression as previously thought. This discovery shows there may be more or different processes happening with white dwarfs that may need to be investigated.

One-fifth of the entire world population watched the live broadcast of the first Moon-walk, so it is no surprise that we all remember or have heard those famous words spoken by Neil Armstrong in 1969. The Apollo program and lunar landings aided the advancement of many fields of engineering, and is considered by many to be the greatest achievement of mankind. Nearly forty years after the end of the Apollo missions, NASA finally plans on returning to the Moon.

Before NASA returns man to the Moon, they plan on doing extensive studies. The first mission to the Moon will be the Lunar Reconnaissance Orbiter (“LRO”), which is scheduled to launch by the end of this year or early next year. The LRO will be equipped with the most sophisticated technology ever sent to the Moon–including instruments to make detailed 3-D maps of the entire lunar surface, locate subsurface water-ice, and record radiation levels to help develop technologies which will ensure the safety of future crews.

Launching with the LRO is the Lunar Crater Observation and Sensing Satellite (“LCROSS”). In 1999, NASA’s Lunar Prospector detected the spectral signature of hydrogen in the Moon’s permanently shadowed polar craters. LCROSS will impact the Moon in one of these craters. The impact will send a plume of material into space, which will be observed by a near-infrared camera, which will analyze the plume for traces of water. Presence of water on the Moon would be an important natural resource for a future lunar colony.

NASA plans on having mankind back on the Moon by 2020. Utilizing the new equipment which is currently being developed as part of the Constellation program, four astronauts will land on the Moon aboard the new Altair Lunar Lander, which will provide life support for the initial week long mission to the Moon. The Lunar Lander will be launched into low-Earth orbit aboard an Ares V Rocket, where it will rendezvous with the Orion crew vehicle.

Returning man to the Moon is the important first step in NASA’s new Moon Mars and beyond initiative proposed by George Bush. The Lunar surface will be explored and studied in an attempt to learn how to build a successful space colony. Risks such as radiation and psychological trauma will have to be fully understood and overcome before any long-term manned missions to Mars, or elsewhere, can be pursued. Having a colony on the Moon will also help us study how the Earth and Moon were formed, and giant telescopes on the Moon will not have the atmospheric interference which is a problem on Earth. Along with the many scientific advances which will follow future lunar landings, returning to the Moon will renew the general population’s interest in space exploration.