Image of the day

My Account

New to Astromart?

Register an account...

Need Help?

News

The Earth Wobbles Back and Forth like a Top

Posted by Guy Pirro 10/22/2021 08:17PM

The Earth Wobbles Back and Forth like a Top

Earth is like a wobbling top spinning in space and the angular momentum keeps it pointing with the same orientation relative to its orbital plane over time. This spinning, however, is affected by numerous forces, including the gravitational tugs of the Moon and the Sun… and the distribution of the continents on the surface of the planet. Geologists have now found new evidence that the solid outer shell of the Earth may have shifted relative to its spin axis about 84 million years ago, causing the planet to wobble back and forth like a top. The new research suggests that the Earth tipped over significantly during the late Cretaceous period due to the distribution of mass on its surface and this could have implications for the evolution of life on Earth.

That’s Strange – Polarized Radio Waves Being Emitted from the Center of the Milky Way

Posted by Guy Pirro 10/14/2021 09:13PM

That’s Strange – Polarized Radio Waves Being Emitted from the Center of the Milky Way

Astronomers have discovered unusual signals coming from the direction of the Milky Way’s center. The radio waves fit no currently understood pattern of variable radio source and could suggest a new class of stellar object. The strangest property of this new signal is that it is has a very high polarization. This means its light oscillates in only one direction (but for this object, that direction rotates over time). The brightness of the object also varies dramatically, by a factor of 100, and the signal switches on and off apparently at random. Astronomers have no any idea as to what the source is.

Kiss the Sky Tonight -- Month of October 2021

Posted by Guy Pirro 10/03/2021 10:45PM

Kiss the Sky Tonight -- Month of October 2021

Welcome to the night sky report for October 2021 -- Your guide to the constellations, deep sky objects, planets, and celestial events that are observable during the month. The crisp, clear October nights are full of celestial showpieces for the backyard sky gazer. Find Pegasus, the flying horse of Greek myth, to pinpoint dense globular star clusters and galaxies. Look for M15, NGC 7331, and M31 - the Andromeda Galaxy. The night sky is truly a celestial showcase. Get outside and explore its wonders from your own backyard.

How Tall are the Highest Mountains on Neutron Stars? – Not as Tall as You Think

Posted by Guy Pirro 09/28/2021 02:11AM

How Tall are the Highest Mountains on Neutron Stars? – Not as Tall as You Think

When the core of a massive star undergoes gravitational collapse at the end of its life, protons and electrons are literally scrunched together, leaving behind one of nature's most wondrous creations: a neutron star. Neutron stars cram roughly 1.3 to 2.5 solar masses into a city-sized sphere perhaps 20 kilometers (12 miles) across. Matter is packed so tightly that a sugar cube sized amount of material would weigh more than 1 billion tons -- about the same as Mount Everest. This squashes every feature on the surface to miniscule dimensions and means that the stellar remnant is an almost perfect sphere. (Think of a neutron star as giant ball bearing in space, but much, much denser). So, if a mountain could form on the surface of a massive neutron star, how tall could it be? That’s the question University of Southampton researchers in the UK have tried to answer… And their answer may surprise you. New models of neutron stars show that their tallest mountains may be only fractions of a millimeter high, due to the huge gravity on these ultra-dense objects.

An Unlucky Star’s Fatal Encounter with a Black Hole

Posted by Guy Pirro 09/22/2021 12:23AM

An Unlucky Star’s Fatal Encounter with a Black Hole

When a star ventures too close to a black hole, gravitational forces create intense tides that break the star apart into a stream of gas, resulting in a cataclysmic phenomenon known as a Tidal Disruption Event (TDE). Tremendous amounts of energy are released, causing the tidal disruption to outshine the combined light of every star in the black hole's host galaxy for months, and even years. By analyzing observations of an X-ray flare and fitting the data with theoretical models, University of Arizona astronomers have documented a fatal encounter between an unlucky star and an intermediate-mass black hole and have been able to make the first measurements of both the black hole's mass and spin.

Surprise – The Milky Way Galaxy is Not as Homogeneous as Previously Thought

Posted by Guy Pirro 09/17/2021 05:24PM

Surprise – The Milky Way Galaxy is Not as Homogeneous as Previously Thought

In order to better understand the history and evolution of the Milky Way, astronomers are studying the composition of the gases and metals that make up an important part of our galaxy. This includes 1) the initial gas coming from outside our galaxy, 2) the gas between the stars inside our galaxy, often enriched with chemical elements, and 3) the dust created by the condensation of the metals present in this gas. Until now, theoretical models assumed that these three elements were homogeneously mixed throughout the Milky Way and reached a level of chemical enrichment similar to the Sun’s atmosphere, called the Solar Metallicity. A team of astronomers from the University of Geneva in Switzerland have observed the composition of these gases in our galaxy and have shown that, contrary to the models established until now, they are not as homogeneously mixed as previously thought. This has an impact on the current understanding of the evolution of galaxies and, as a result, our understanding of the Milky Way’s evolution will need to be revisited.

Accidental Discovery Hints at a Hidden Population of Brown Dwarfs in Our Galaxy

Posted by Guy Pirro 09/12/2021 02:59AM

Accidental Discovery Hints at a Hidden Population of Brown Dwarfs in Our Galaxy

Brown dwarfs aren’t quite stars and aren’t quite planets, and a new study suggests there might be more of them lurking in our galaxy than scientists previously thought. A new study offers a tantalizing explanation for how a peculiar cosmic object, nicknamed “The Accident,” came to be. “The Accident” is a brown dwarf. Though they form like stars, these objects don’t have enough mass to kick-start nuclear fusion, the process that causes stars to shine. And while brown dwarfs often defy characterization, astronomers have a good grasp on their general characteristics… Or they did, until they found this one.

Kiss the Sky Tonight -- Month of September 2021

Posted by Guy Pirro 09/03/2021 07:07PM

Kiss the Sky Tonight -- Month of September 2021

Welcome to the night sky report for September 2021 -- Your guide to the constellations, deep sky objects, planets, and celestial events that are observable during the month. In September, Pegasus becomes increasingly prominent in the southeastern sky, allowing stargazers to locate globular clusters M2 (NGC 7089), M30 (NGC 7099), as well as a nearby double star, Alpha Capricorni, which is an optical double (but not a binary pair). The night sky is truly a celestial showcase. Get outside and explore its wonders from your own backyard.

Natural Particle Accelerators in Space Leave the Large Hadron Collider Energies in the Dust

Posted by Guy Pirro 08/28/2021 03:58PM

Natural Particle Accelerators in Space Leave the Large Hadron Collider Energies in the Dust

Since they were first detected more than a hundred years ago, Cosmic Rays – highly energetic particles that continuously rain down on Earth from space – have posed an enduring mystery. What creates and propels the particles across vast distances? Where do they come from? Using an internationally organized effort, scientist have for the first time located a source of high-energy cosmic neutrinos -- ghostly elementary cosmic particles that travel billions of light years through the universe, flying unaffected through stars, planets, and entire galaxies. The joint observation campaign was triggered by a single neutrino that was recorded by the IceCube Neutrino Telescope at the South Pole in September 2017. The energy of this specific neutrino was around 300 Tera-ElectronVolts – That is more than 40 times the energy produced by the world’s largest particle accelerator, the CERN Large Hadron Collider (LHC) in Switzerland. Telescopes on Earth and in space were able quickly follow-up the initial detection with more detailed observations that determined the exotic particle had originated in a galaxy nearly four billion light years away in the constellation Orion, where a gigantic black hole was behaving like a natural particle accelerator.

Researchers in Switzerland Calculate the Value of Pi to a Record of 62.8 Trillion Digits

Posted by Guy Pirro 08/19/2021 03:52AM

Researchers in Switzerland Calculate the Value of Pi to a Record of 62.8 Trillion Digits

By early Saturday morning, August 14th, it was clear -- The world record calculation for the number Pi had fallen to a Swiss team at the University of Applied Sciences in Graubunden. The record is now back in Switzerland after two previous American world records. The high performance computer at the Center for Data Analytics, Visualization, and Simulation (DAViS) exceeded the old world record of 50 trillion digits by adding 12.8 trillion new, previously unknown digits to the back-end of the irrational number known the world over as Pi. The last ten known digits of Pi are now 3.1415926535…7817924264.

Yerkes Observatory Lives On as the Largest Refractor Telescope Ever Built

Posted by Guy Pirro 08/13/2021 06:06PM

Yerkes Observatory Lives On as the Largest Refractor Telescope Ever Built

The Yerkes Observatory in the Village of Williams Bay, Wisconsin, on the shores of Geneva Lake in Walworth County, was completed in 1897. The observatory contains the largest refractor telescope in the world and is often referred to as “the birthplace of modern astrophysics.” The Chicago millionaire Charles Tyson Yerkes Jr. provided funding starting in 1892 to construct the Great Refractor and build the observatory that bears his name. He donated the facility to the University of Chicago in October 1897. The university owned Yerkes Observatory until May 1, 2020 when it, together with fifty acres of surrounding land, was donated to the Yerkes Future Foundation, an independent, charitable, nonprofit organization. The Observatory and grounds are currently undergoing restoration and renovation in order to prepare for public access later this year (or possibly next) and to ready the Yerkes landmark for another 125 years of science and discovery.

Astronomers Spot an Unusual Set of X-ray Light Echoes Around a Black Hole

Posted by Guy Pirro 08/06/2021 03:39PM

Astronomers Spot an Unusual Set of X-ray Light Echoes Around a Black Hole

V404 Cygni is a black hole binary system located about 7800 light years away from Earth. The black hole is actively pulling material away from a companion star (with about half the mass of the Sun) into a disk around the invisible object. This material glows in X-rays, so astronomers refer to these systems as "X-ray Binaries." In 2015, Swift discovered a burst of X-rays from V404 Cygni. The burst created high-energy rings from a phenomenon known as light echoes. Instead of sound waves bouncing off a canyon wall, the light echoes around V404 Cygni were produced when a burst of X-rays from the black hole system bounced off of dust clouds between V404 Cygni and Earth. A team of researchers at the University of Wisconsin recently analyzed Swift and Chandra observations of the system. The rings tell astronomers not only about the black hole's behavior, but also about the landscape between V404 Cygni and Earth. The observed light echoes appear as narrow rings rather than wide rings or haloes because the X-ray burst lasted only a relatively short period of time.

Kiss the Sky Tonight -- Month of August 2021

Posted by Guy Pirro 08/03/2021 12:00AM

Kiss the Sky Tonight -- Month of August 2021

Welcome to the night sky report for August 2021 -- Your guide to the constellations, deep sky objects, planets, and celestial events that are observable during the month. In August, a flock of star-studded figures soars overhead. Look for the constellation Lyra, shaped as a small parallelogram, which points to Epsilon Lyrae and the Ring Nebula. You can also spot three bright summer stars: Vega, Deneb, and Altair, which form the Summer Triangle. Find a dark location to enjoy the Perseid meteors on August 11 and then check out Jupiter and Saturn all night long all month. The full moon on August 22nd is what's known as a "seasonal blue moon," as it's the third full moon out of four this season, where normally in each season there are only three. This happens every two-and-a-half to three years or as they say, "once in a blue moon." The night sky is truly a celestial showcase. Get outside and explore its wonders from your own backyard.

It’s Finally Here! -- Assembly of NASA’s First SLS (Saturn V on Steroids) Begins at Kennedy Space Center

Posted by Guy Pirro 07/26/2021 02:48PM

It’s Finally Here! -- Assembly of NASA’s First SLS (Saturn V on Steroids) Begins at Kennedy Space Center

It’s finally here! -- NASA’s Space Launch System (SLS) is a super-heavy-lift launch vehicle that provides the foundation for human exploration beyond Earth’s orbit. The core stage of the SLS rocket has been delivered to NASA’s Kennedy Space Center, placed on the mobile launcher, and attached to the twin solid rocket boosters inside the Vehicle Assembly Building (VAB). Serving as the backbone of the giant rocket, the core stage supports the weight of the payload, upper stage, and crew vehicle, and is the main structural element that bears the full thrust of its four powerful engines and two five-segment solid rocket boosters. The 188,000-pound core stage, with its four RS-25 engines, will provide more than 2 million pounds of thrust during launch and ascent and, coupled with the boosters, will provide more than 8.8 million pounds of thrust to send the Artemis I mission to space. Artemis I will be an uncrewed test of the Orion spacecraft and SLS rocket as an integrated system ahead of crewed flights to the Moon.

NASA’s Juno Spacecraft Gets a Close Look at Ganymede - Jupiter’s Largest Moon

Posted by Guy Pirro 07/16/2021 04:10AM

NASA’s Juno Spacecraft Gets a Close Look at Ganymede - Jupiter’s Largest Moon

Ganymede, Jupiter’s largest moon, is bigger than the planet Mercury and is the only moon in the solar system with its own magnetosphere – a bubble-shaped region of charged particles surrounding the celestial body. On Monday, June 7th, NASA’s Juno spacecraft came within 645 miles (1038 kilometers) of the surface of Ganymede. The flyby was the closest a spacecraft has come to the solar system’s largest natural satellite since NASA’s Galileo spacecraft made its close approach back on May 20, 2000. Along with striking imagery, the solar-powered spacecraft’s flyby yielded insights into the moon’s composition, ionosphere, magnetosphere, and ice shell.