The Crab Pulsar (PSR B0531+21) is a relatively young neutron star. The star is the central star in the Crab Nebula, a remnant of the supernova SN 1054, which was widely observed on Earth in the year 1054. Discovered in 1968, the pulsar was the first to be connected with a supernova remnant.
The Crab Pulsar is one of very few pulsars to be identified optically. The optical pulsar is roughly 20 kilometres (12 mi) in diameter and the pulsar “beams” rotate once every 33 milliseconds, or 30 times each second.
The outflowing relativistic wind from the neutron star generates synchrotron emission, which produces the bulk of the emission from the nebula, seen from radio wavesthrough to gamma rays. The most dynamic feature in the inner part of the nebula is the point where the pulsar’s equatorial wind slams into the surrounding nebula, forming a termination shock.
The shape and position of this feature shifts rapidly, with the equatorial wind appearing as a series of wisp-like features that steepen, brighten, then fade as they move away from the pulsar into the main body of the nebula. The period of the pulsar’s rotation is slowing by 38 nanoseconds per day due to the large amounts of energy carried away in the pulsar wind.
The Crab Nebula is often used as a calibration source in X-ray astronomy. It is very bright in X-rays and the flux density and spectrum are known to be constant, with the exception of the pulsar itself.
source | A History of the Crab Nebula
images: NASA/ESA, Hubble, Cambridge University Lucky Imaging Group, NASA/CXC/ASU/J.Hester et al.
Orion Launch Abort System Attitude Control Motor Hot-Fire Test via NASA https://ift.tt/2Wk4fYE
And that’s when Earth made dolphins. LOL.
This is the moment of today’s Soyuz rocket failure. It happened as the 4 side boosters were being jettisoned. Very glad the crew is safely back on the ground. (at Baikonur Cosmodrome) https://www.instagram.com/p/BozMRz0Hm2Y/?utm_source=ig_tumblr_share&igshid=168pfhpjc77cm
Thought For The Day
Never think you’re nothing. Never cry at night over not being pretty enough. Never tell yourself you’ll never be good enough. Because to someone, you’re everything. To someone, you’re gorgeous. To someone, you are the world.
Follow this tumblr for more quotes to motivate you (via thelovewhisperer)
This mosaic image from the NASA/ESA/ASI Cassini-Huygens spacecraft is centered at 9 degrees north latitude, 254 degrees west longitude. The image was acquired at a distance of about 57,800 km from Rhea.
Image credit: NASA/JPL
NGC 3576, Statue of Liberty Nebula
Venus and the Triply Ultraviolet Sun : An unusual type of solar eclipse occurred in 2012. Usually it is the Earth’s Moon that eclipses the Sun. That year, most unusually, the planet Venus took a turn. Like a solar eclipse by the Moon, the phase of Venus became a continually thinner crescent as Venus became increasingly better aligned with the Sun. Eventually the alignment became perfect and the phase of Venus dropped to zero. The dark spot of Venus crossed our parent star. The situation could technically be labeled a Venusian annular eclipse with an extraordinarily large ring of fire. Pictured here during the occultation, the Sun was imaged in three colors of ultraviolet light by the Earth-orbiting Solar Dynamics Observatory, with the dark region toward the right corresponding to a coronal hole. Hours later, as Venus continued in its orbit, a slight crescent phase appeared again. The next Venusian transit across the Sun will occur in 2117. via NASA
October is the time of year for the Orionids Meteor Shower! Pictured here, over two dozen meteors were caught in successively added exposures last October in Inner Mongolia. The featured image shows multiple meteor streaks that can all be connected to a single small region on the sky called the radiant, here visible just above and to the left of the belt of Orion. The Orionids meteors started as sand sized bits expelled from Comet Halley during one of its trips to the inner Solar System. Comet Halley is actually responsible for two known meteor showers, the other known as the Eta Aquarids and visible every May.
Next month, the Leonids Meteor Shower from Comet Tempel-Tuttle should also result in some bright meteor streaks.
Image Credit & Copyright: Yin Hao