It was an ordinary day. Reading about astronomers that know that everything that has ever happened in the history of the universe has left a mark on the sky. With the right technology, much of it is now decipherable. For the past quarter-century, NASA's Chandra X-ray Observatory has been recording the roiling aftermath of two mighty supernova explosions that occurred hundreds of years ago, far out in space. This spring, the astronomers who operate Chandra combined its X-ray images into videos that document the evolution of two astrophysical landmarks: the Crab Nebula, in the constellation Tarus, and Cassiopeia A, a gas bubble and hub of radio noise in the constellation Cassiopeia. The videos show twisting, drifting ribbons of the remains of the star being churned by shock waves and illuminated by radiation from the dense, spinning cores left behind. They were made to celebrate the 25th anniversary of the observatory, which was launched into space in 1999 and has been a workhorse of cosmology and astrophysics ever since.
|
Cassiopeia A in infrared captured by the James Webb Space Telescope. |
Chandra was one of four "Great Observatories" that NASA launched in the 1990s. The others were the Compton Gamma Ray Obervatory and the infrared Spitzer Space Telescope, both of which have since been shut down and the Hubble Race Telescope, which remains on duty. Chandra's job is to observe the cosmos through X-ray goggles and study its hottest and most violent phenomena, like black hole, exploding stars and blazing-hot intergalactic gas. Because X-rays are blocked by Earth's atmosphere, these astrophysical events can be studied only from space. Chandra was the dream child of Riccardo Giacconi, a physicist who pioneered the field of X-ray astronomy and won the Nobel Prize in physics in 2002. Astronomers now have a multispectral view of some of the weirdest events in the universe thanks to Chandra, the Hubble Space Telescope, which sees ordinary light, and the James Webb Space Telescope, which sees infrared light. In 2003, astronomers using Chandra discovered a sinking black hole that had been periodically blowing bubbles in the hot, diffuse gas pervading a cluster of galaxies some 250 million light years away. The activity was producing sound waves - an eternal note of B flat belted into intergalactic plasma. Chandra's X-ray observations have also revealed that enigmatic flecks of light in the early universe, initially detected by the Webb telescope, were actually quasars: young galaxies harboring supermassive black holes. That finding caused some astrophysicists to reconsider their ideas about how and when such massive black holes form. In June, Chandra scientists announced the discovery a black hole with a mass of 80 million suns that was kicking up a rumpus back when the universe was only a half-billion. years old. Chandra has also long tracked exploding stars. The Crab Nebula was created in the year 1054 in an explosion that was seen by Chinese and Japanese astronomers and recorded in Native American pictographs. The nebula harbors one of the first known pulsars - a spinning neutron star that flicks a pulse of radio energy 30 times per second like a super fast lighthouse beam. The heavens are and forever will be a display of wonderment! It was another extraordinary day in the life of an ordinary guy.
No comments:
Post a Comment