Astronomy Oddities 1

 

                                                                   Betelgeuse

Algol.  Algol (Beta Persei) is known as the Demon Star and is a variable star.  It is a bright, multiple eclipsing three-star system (and two suspected stellar components) in the constellation of Perseus.  It is one of the first non-nova variable stars to be discovered.  It consists of a 3.7 solar mass main sequence star in close orbit with a 0.8 solar mass sub-giant star, which is very odd.  Studies of Algol led to the Algol paradox in the theory of stellar evolution: although components of a binary star form at the same time, and massive stars evolve much faster than the less massive stars, the more massive component Algol Aa1 is still in the main sequence, but the less massive Algol Aa2 is a subgiant star at a later evolutionary stage.  [source: McClure, “Algol the Demon Star of Perseus,” EarthSky, Oct 27, 2022]

Aurora.  An aurora is a natural light display mostly seen around the Arctic and Antarctic regions.  Auroras display dynamic patterns of brilliant light that appear as curtains, rays, spirals, or flickers covering the entire sky.  They are more commonly seen around the vernal and autumnal equinoxes, though it is not known why this should be so.

Betelgeuse.  Betelgeuse is a red supergiant and one of the largest stars visible to the naked eye.  It is over 500 light-years away in the constellation Orion.  In 2019, it suddenly and mysteriously dimmed by a factor of three, from magnitude 0.5 to 1.7.  It then returned to a more normal brightness range.  A study suggested that occluding dust was created by a surface mass-ejection from the star’s surface.  This cast material millions of miles from the star that then cooled to form the dust that caused the star’s dimming. At the same time, the temperature of the star fell by at least 170 kelvins.     [source: Gasparini, “Betelgeuse ‘Great Dimming’ Mystery Solved by Satellite Photobomb,” Scientific American, June 17, 2022]

Black Hole.  The largest black hole ever discovered can fit 30 billion suns.  The black hole was found in the center of galaxy cluster Abell 1201.  It was found using gravitational lensing.  It was found in an image captured by the Hubble Space Telescope.  [sources: Pultarova, “The largest black hole,” space.com, Mar 29, 2023 and Nightingale et al, “Abell 1201: Detection of an Ultramassive Black Hole in a Strong Gravitation Lens,” Monthly Notices of the Royal Astronomical Society, Mar 29, 2023]

Blazar.  A blazar is a galaxy with an active galactic nucleus (AGN – black hole) with a relativistic jet (a jet composed of ionized matter traveling at nearly the speed of light) directed very nearly towards an observer.  The jet makes blazars appear much brighter than they would be if the jet were pointed in a direction away from Earth.  A galaxy named PBC J2339.9-2343 is a giant radio galaxy that has a blazer in its core.  The blazar is 656 million light-years away.  [source: Musto, “Black hole jet from newly-classified galaxy changes direction toward Earth,” Fox News: Astronomy, Apr 1, 2023]

Boomerang Nebula.  The Boomerang Nebula is a protoplanetary nebula located 5,000 light-years away in the constellation Centaurus.  It is the coldest region of space.  Its temperature is 1 Kelvin, or -457 degrees Fahrenheit (-272 degrees Celsius).  The nebula is composed of gas being expelled by a dying star at its heart.  The wins driving away the gas is blowing at 310,000 mph.

Brahe, Tycho.  Tycho Brahe (1546-1601) was one of the oddest scientists in history.  At age 20, he lost part of his nose in a drunken sword duel against his cousin, and replaced it with a metal prosthesis.  He died because he was too polite to leave the dinner table to use the bathroom and developed a bladder or kidney ailment.  He obsessively charted the positions of every visible heavenly body.  He believed that the Earth, not the Sun, was the center of the universe, despite all the data he collected to prove otherwise.  He was the last major astronomer before the invention of the telescope.

Brown Dwarfs.  Brown dwarfs (also called failed stars) are substellar objects that are not massive enough to sustain nuclear fusion in their cores.  They can be 13 to 80 times the size of Jupiter.  The Milky Way has 1 brown dwarf for every 6 normal stars.  The Milky Way galaxy contains about 100 billion brown dwarfs.   Brown dwarfs were theorized in the 1960s, but not until 1988 and the mid-1990s that they were first discovered.  In 1975, Jill Tarter coined the term “brown dwarf.”  The nearest known brown dwarf, in the Luhman 16 system, is 6.5 light-years away.  [source: Eicher, “How Many Brown Dwarfs Exist?,” Astronomy, July 1, 2019]

Butterfly Nebula.  The Butterfly Nebula (NGC 6302) is a bipolar nebula in the constellation Scorpius.  The structure in the nebula is among the most complex ever observed in planetary nebula.  Astronomers believe the winged shape is created from a gravitational tug of a second star orbiting the nebula’s “parent” star, causing the material to expand into nebular lobes or “wings.”  Powerful winds caused huge changes in the material within the wings.  What’s unclear is how this change is possible from a star with no remaining fuel.  Its central star is one of the hottest stars known, with a surface temperature over 250,000 degrees Celsius.  [source: Solis-Moreira, “Butterfly Nebula’s wings creating a space mystery,” studyfinds.org, Jan 19, 2023] 

Cepheid Variable.  A Cepheid variable is a type of variable star that pulsates radially, varying in both diameter and temperature. It changes in brightness, with a well-defined stable period and amplitude.  Cepheids are important cosmic benchmarks for scaling galactic and extragalactic distances. A strong direct relationship exists between a Cepheid variable's luminosity and its pulsation period.  This tells one the distance to the star by comparing its known luminosity to its observed brightness.  Cepheids literally pulse: get bigger and then smaller in size.  As they expand and contract, their brightness changes.

Ceres.  Ceres is a dwarf planet in the asteroid belt between Mars and Jupiter.  It was the first asteroid discovered in 1801.  In 2014, emissions of water vapor were detected, creating a transient atmosphere known as an exosphere. 

Chariklo.  10199 Chariklo is an asteroid the orbits the Sun between Saturn and Uranus.  In 2014, it was discovered that this asteroid has two rings around itself.  It is the first minor planet known to have rings.  They were most likely formed after a collision that scattered debris around the asteroid.  The asteroid is 155 miles in diameter.  [source: Carter, “Welcome To Chariklo, A Ringed World In The Solar System Just Examined By The Webb Telescope,” Forbes, Jan 25, 2023]

Compact Ellipticals.  Compact elliptical (cEs) are galaxies characterized by unusually high surface brightness for their luminosity.  The formation of these low-mass, but metal-rich and compact galaxies has been a long-standing puzzle.  Compact elliptical are very rare and only a handful are known.  [source: “The Formation of Compact elliptical Galaxies in the Vicinity of a Massive Galaxy,” The Astrophysical Journal, April 16, 2019]

COS-87259.  COS-87259 is an early galaxy that is forming stars at a rate 1,000 times that of our Milky Way.  It contains more than a billion solar masses worth of interstellar dust.  There is a quick-growing black hole at the center of this galaxy.  The black hole is a new kind of primordial type that is densely covered in cosmic “dust,” which causes almost all of its light to be released in the mid-infrared region of the electromagnetic spectrum.  [source: Chattaraj, “Researchers Found a Quick-growing Black Hole at the Centre of COS-87259 Galaxy,” Transcontinental Times, Feb 26, 2023]

Cosmological Constant.  The cosmological constant is the energy density of space, or vacuum energy.  The Cosmological constant (which controls the expansion speed of the universe) refers to the balance of the attractive force of gravity with a hypothesized repulsive force of space observable only at very large size scales. It must be very close to zero, that is, these two forces must be nearly perfectly balanced. To get the right balance, the cosmological constant must be fine-tuned to something like 1 part in 10¹²⁰. If it were just slightly more positive, the universe would fly apart.  If it were slightly negative, and the universe would collapse.  It is closely associated with the concept of dark energy.  Around 68% of the mass-energy density of the universe can be attributed to dark energy.  The cosmological constant is the simplest possible explanation for dark energy.  The cosmological constant problem is the disagreement between the observed values of vacuum energy density (the small value of the cosmological constant) and theoretical large value of zero-point energy suggested by quantum field theory.   the quantum vacuum energy contribution to the effective cosmological constant is calculated to be between 50 and as much as 120 orders of magnitude greater than observed, a state of affairs described by physicists as "the largest discrepancy between theory and experiment in all of science" and "the worst theoretical prediction in the history of physics.”  [source: Petterson, “An initial survey of the “four fundamental forces” and the “cosmological constant,” patheos.com, Jan 23, 2023]

Dark Energy.  Dark energy is an unknown form of energy that affects the universe on the largest scales.  It is the dominating form of energy in the universe, and is driving the acceleration expansion of the universe.  Its nature remains a complete mystery.  The first observational evidence for its existence came from measurements of supernovas, which showed that the universe does not expand at a constant rate; rather, the universe's expansion is accelerating. [source: Lea, “What is dark energy?,” space.com, Nov 24, 2022] 

Dark Matter.  For the first time, scientists may have discovered indirect evidence that large amounts of invisible dark matter surround black holes.  Dark matter makes up around 85% of all matter in the universe.  Dark matter doesn’t interact with light and cannot be seen.  However, dark matter does interact gravitationally.  Astronomers watched the orbits of two stars being decayed or slightly slowed wile move around their companion black holes.  The slow-down may be the result of dark matter surrounding the black holes which generated significant friction and a drag on the starts as the whipped around the black holes.  [source: Lea, “Black holes may be swallowing invisible matter that slows the movement of stars,” space.com, Mar 28, 2023]

Dispersion.  A Fast Radio Burst (FRB) simultaneously generates both high frequency radio waves (the equivalent of blue light) and low frequency radio waves (the equivalent of red light), the different colors of radio waves might be expected to arrive at a telescope at the same time. But that’s not what happens. As an FRB passes through gas, it slows down – more so for the high frequencies than the low frequencies. The result is a delay between the different frequencies or colors reaching our telescope, effectively smearing the radio burst’s signal out in time.  Astronomers call this smearing “dispersion” and are able to use it as a tool to detect otherwise invisible gas throughout the cosmos.  Astronomers use the dispersion method to measure how much gas is present in the Milky Way’s halo – an “atmosphere” of the Milky Way that extends outwards by around a half a million light-years in all directions.  From this method, astronomers discovered that the Milky Way halo contains much less gas than previous models had predicted.  [source: MacSween, “Fast radio bursts used as ‘searchlights’ to detect gas in Milky Way,” University of Toronto News, Mar 30, 2223]

Earendel.  Earendel (WHK017-LS) is the earliest and most distant star astronomers have observed.  It is in the constellation Cetus and was discovered on March 30, 2022, by the Hubble Space Telescope.  It is 28 billion light-years away using commoving distances.  Comoving distances factors out the expansion of the universe, giving a distance that does not change in time due to the expansion of space.  The star was detectable due to gravitational lensing caused by a massive galaxy cluster between it and the Earth.  [source: “A highly magnified star at redshift 6.2,”Nature, Mar 31, 2022] 

EBLM J0555-57.  EBLM J0555-57 is a triple star system approximately 670 light-years from Earth in the constellation Pictor. EBLM J0555-57Ab, the smallest star in the system and the smallest star ever found, orbits its primary star with a period of 7.8 days, with a mass sufficient to barely enable the fusion of hydrogen in its core.  EBLM J0555-57Ab is about the size of Saturn and a mass of 85 times the mass of Jupiter. [Byrd, “Astronomers find the smallest star yet,” EarthSky, July 12, 2017] 

Enceladus.  Enceladus is one of 83 moons of Saturn, about 310 miles in diameter.  It is mostly covered by fresh, clean ice, making it the whitest and most reflective body in the Solar System.  It is known for spraying out tiny icy silica particles.  The particles are a key component of the second outermost ring (the E-ring) around Saturn.  The surface temperature reaches -198 degrees Celsius, far colder than a light-absorbing body would be.  Over 100 geysers have been identified on this moon.  It shoots out 440  pounds of ice per second.  [source: University of California – Los Angeles, Feb 23, 2023] 

Europa.  Europa is the smallest of the four Galilean moons orbiting Jupiter.  It has the smoothest surface of any known solid object in the Solar system.  Europa is slightly smaller than Earth’s moon.  It has a water-ice crust.  It has a very thin atmosphere, composed primarily of oxygen.  The icy shell of Europa rotates at a different rate than its interior.  Europa has an internal ocean under its icy outer shell.  It is an enormous body of salty water swirling around Europa’s rocky interior. [source: “Study Finds Ocean Currents May Affect Rotation of Europa’s Icy Crust,” Jet Propulsion Laboratory, March 13, 2023]

Exoplanet.  An exoplanet or extrasolar planet is a planet outside the Solar System.  As of March 2023, there have been over 5,000 confirmed exoplanets in over 3,100 star systems, with over 700 systems having more than one planet.  The methods used to detect an exoplanet include transit photometry, radio velocity method, Doppler spectroscopy, and gravitational microlensing.  The least massive planet, named Draugr, is about twice the mass of the moon.  The most massive planet, named HR 2562, is about 30 times the mass of Jupiter.  In 1988, the first suspected scientific detection of an exoplanet occurred.  In 1992, the first confirmation of detection occurred, with an exoplanet revolving around a pulsar.  In 1995, the first confirmation of an exoplanet orbiting a main-sequence star occurred.   This was detected by Michel Mayor and Didier Queloz of the University of Geneva.  The two shared the 2019 Nobel Prize in Physics with James Peebles who contributed theoretical discoveries in physical cosmology.  In 2019, an earth-sized planet was found in the habitable zone of a nearby star.  It was discovered from data from the Transiting Exoplanet Survey Satellite (TESS). [source: Kopparapu, “Earth-Sized Planet Found in the Habitable Zone of a Nearby Star,” Live Science, Jan 7, 2020]