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Astronomers Capture First-ever Image of a Black Hole

Posted by Guy Pirro 04/10/2019 07:38PM

Astronomers Capture First-ever Image of a Black Hole

M87 (also known as Virgo A or NGC 4486) is one of the most massive galaxies in the local Universe. To give you an idea of its size, M87 has a large population of globular clusters (about 12,000) compared with the 150 to 200 orbiting our Milky Way galaxy. It also has a jet of energetic plasma traveling at relativistic speed that originates at the core and extends at least 4900 light-years. It is one of the brightest radio sources in the sky and a popular target for both amateur and professional astronomers. As in most, if not all, spiral galaxies, M87 has a supermassive black hole at its center. Black holes are extraordinary cosmic objects with enormous masses but extremely compact sizes. The extreme density of these objects affects their immediate environment in peculiar ways, warping space-time and super-heating any surrounding material. To date, no one has ever imaged a black hole. But that has now changed with the Event Horizon Telescope (EHT), a planet-scale array of eight ground-based radio telescopes forged through an international collaboration. The EHT was designed specifically to capture images of a black hole. In coordinated press conferences across the globe, EHT researchers revealed the first direct visual evidence of a supermassive black hole and its shadow. The image shows the black hole at the center of M87.

Kiss the Sky Tonight -- Month of April 2019

Posted by Guy Pirro 04/08/2019 02:21AM

Kiss the Sky Tonight -- Month of April 2019

Welcome to the night sky report for April 2019 -- Your guide to the constellations, deep sky objects, planets, and celestial events that are observable during the month. Clear April nights are filled with starry creatures. Look for the Great Bear and Leo the Lion. You can also spot galaxies like M101, M81, and M82. The night sky is truly a celestial showcase. Get outside and explore its wonders from your own backyard… Let’s follow the advice of James Marshall Hendrix (apparently a fellow admirer of the heavens), who famously proclaimed "Excuse me while I kiss the sky."

Another Theory Bites the Dust -- Dark Matter is Not Made-Up of Tiny Primordial Black Holes

Posted by Guy Pirro 04/03/2019 03:19PM

Another Theory Bites the Dust -- Dark Matter is Not Made-Up of Tiny Primordial Black Holes

An international team of researchers has put a theory speculated by the late Stephen Hawking to its most rigorous test to date, and their results have ruled out the possibility that primordial black holes smaller than a tenth of a millimeter make up most of dark matter. Scientists “know” that 85 percent of the matter in the Universe is made up of dark matter. Its gravitational force prevents stars in our Milky Way from flying apart. However, attempts to detect such dark matter particles using underground experiments, or accelerator experiments including the world’s largest accelerator, the Large Hadron Collider, have failed so far. This has led scientists to consider Hawking's 1974 theory of the existence of primordial black holes, born shortly after the Big Bang, and his speculation that they could make up a large fraction of the elusive dark matter scientists are trying to discover today. The team’s results showed primordial black holes can contribute no more than 0.1 percent of all dark matter mass. Therefore, it is unlikely the theory is true.

Have You Lost Your Sense of Direction? Then Use the Magnetic Compass in Your Brain

Posted by Guy Pirro 03/23/2019 11:23PM

Have You Lost Your Sense of Direction? Then Use the Magnetic Compass in Your Brain

Aristotle described the five basic human senses as vision, hearing, taste, smell, and touch. Now, it seems we can add another sense – magnetoreception. Many animals have magnetoreception, so why not humans? Honeybees, salmon, turtles, birds, whales, and bats use the geomagnetic field to help them navigate, and dogs can be trained to locate buried magnets. Apparently, many humans are also able to unconsciously detect changes in Earth-strength magnetic fields, according to scientists at Caltech and the University of Tokyo.

Could Photon Mass Contribute to the Rotational Dynamics of Galaxies and Negate the Need for Dark Matter?

Posted by Guy Pirro 03/18/2019 06:45PM

Could Photon Mass Contribute to the Rotational Dynamics of Galaxies and Negate the Need for Dark Matter?

The rotation of stars in galaxies like our Milky Way is puzzling. The orbital speed of stars should decrease with their distance from the center of the galaxy, but in fact stars in the middle and outer regions of galaxies have the same rotational speed. This may be due to the gravitational effect of matter that we can't see. Although researchers have been seeking it for decades, the existence this imaginary construct referred to as “Dark Matter” has yet to be definitively proven -- We still don't know what it is made of or even if it exists at all. With this in mind, physicists in Germany have suggested that the rotational dynamics of galaxies might be explained by other factors. They hypothesize that the mass of photons, which are particles of light, might be responsible. The mass of a photon is extremely small and is usually ignored when analyzing atomic and nuclear processes. However, such a vanishingly tiny mass could have an effect on large-scale astrophysical phenomena.

So, How Much Does Our Milky Way Galaxy Weigh?

Posted by Guy Pirro 03/09/2019 03:53AM

So, How Much Does Our Milky Way Galaxy Weigh?

We can't put the whole Milky Way Galaxy on a scale, but astronomers have been able to come up with one of the most accurate measurements yet of our galaxy's mass. Curious astronomers teamed up the Hubble Space Telescope and European Space Agency's Gaia satellite to precisely study the motions of globular star clusters that orbit our galaxy like bees around a hive. The faster the clusters move under the entire galaxy's gravitational pull, the more massive it is. The researchers concluded the galaxy weighs 1.5 trillion solar masses (one solar mass is the mass of our Sun). However most of it locked up in dark matter. The new mass estimate puts our galaxy on the beefier side, compared to other galaxies in the universe. The lightest galaxies are around a billion solar masses, while the heaviest are 30 trillion, or 30,000 times more massive.

Kiss the Sky Tonight -- Month of March 2019

Posted by Guy Pirro 03/01/2019 04:33PM

Kiss the Sky Tonight -- Month of March 2019

Welcome to the night sky report for March 2019 -- Your guide to the constellations, deep sky objects, planets, and celestial events that are observable during the month. In March, the stars of spring lie eastward. Look for the constellations Gemini and Cancer to spot interesting celestial features like the Beehive Cluster. The night sky is truly a celestial showcase. Get outside and explore its wonders from your own backyard.

Is the Universe Hiding its Missing Mass in the Warm-Hot Intergalactic Medium?

Posted by Guy Pirro 02/23/2019 08:58AM

Is the Universe Hiding its Missing Mass in the Warm-Hot Intergalactic Medium?

Astronomers have spent decades looking for something that sounds like it would be hard to miss: about a third of the “normal” matter in the Universe. New results from NASA’s Chandra X-ray Observatory may have helped them locate this elusive expanse of missing matter. In the time between the first few minutes and the first billion years or so, much of the normal matter (meaning hydrogen, helium and other elements) made its way into cosmic dust, gas, and objects such as stars and planets that telescopes can see in the present day Universe. The problem is that when astronomers add up the mass of all the normal matter in the present day Universe, about a third of it can't be found. One idea is that the missing mass gathered into gigantic strands or filaments of “Warm” (temperature less than 100,000 Kelvin) and “Hot” (temperature greater than 100,000 Kelvin) gas in intergalactic space. These filaments are known by astronomers as the "Warm-Hot Intergalactic Medium" or WHIM. They are invisible to optical light telescopes, but some of the warm gas in filaments has been detected in ultraviolet light. Using a new technique, researchers have found new and strong evidence for the hot component of the WHIM based on data from Chandra and other telescopes. (Please note that the missing mass described here is distinct from the still mysterious dark matter).

Earth’s Magnetic Field Vibrates Like a Drum

Posted by Guy Pirro 02/17/2019 08:35AM

Earth’s Magnetic Field Vibrates Like a Drum

Using data from NASA’s THEMIS mission, scientists have discovered ¬that when the Earth’s magnetopause is struck by a jet of plasma from the Sun, it vibrates like a drum, with waves echoing back and forth along its surface, much like they do on top of a drumhead. The new discovery comes several decades after such behavior was first theorized.

Hey… We’re Over Here – Powerful Laser Could be Used as a Beacon to Attract Alien Attention to Earth

Posted by Guy Pirro 02/08/2019 10:48AM

Hey… We’re Over Here – Powerful Laser Could be Used as a Beacon to Attract Alien Attention to Earth

If extraterrestrial intelligence exists somewhere in our galaxy, a new MIT study proposes that laser technology on Earth could, in principle, be fashioned into something of a planetary porch light -- a beacon strong enough to attract attention from as far away as 20,000 light years. The findings suggest that if a high-powered 1 to 2 megawatt laser were focused through a massive 30 to 45 meter telescope and aimed out into space, the combination would produce a beam of infrared radiation strong enough to stand out from the sun’s energy. Such a signal could be detectable by alien astronomers performing a cursory survey of our section of the Milky Way -- especially if those astronomers live in nearby systems, such as around Proxima Centauri, the nearest star to Earth, or TRAPPIST-1, a star about 40 light years away that hosts seven exo-planets, three of which are potentially habitable.

Kiss the Sky Tonight -- Month of February 2019

Posted by Guy Pirro 01/29/2019 02:18AM

Kiss the Sky Tonight -- Month of February 2019

Welcome to the night sky report for February 2019 -- Your guide to the constellations, deep sky objects, planets, and celestial events that are observable during the month. In February, the Winter Triangle is your guide to the night sky. The northern hemisphere is treated to views of the stars Procyon, Sirius, and Betelgeuse. Keep watching for the awe-inspiring views of the Orion Nebula, which is sculpted by the stellar winds of central bright stars. The night sky is truly a celestial showcase. Get outside and explore its wonders from your own backyard.

Mystery Orbits in Outermost Reaches of Solar System not Caused by ‘Planet Nine’

Posted by Guy Pirro 01/21/2019 01:27AM

Mystery Orbits in Outermost Reaches of Solar System not Caused by ‘Planet Nine’

The strange orbits of some objects in the farthest reaches of our solar system, hypothesized by some astronomers to be perturbed by an unknown planet (Planet 9), can instead be explained by the combined gravitational force of small objects in the Kuiper Belt orbiting the Sun beyond Neptune. While the new theory is not the first to propose that the gravitational forces of a massive disc made of small objects could avoid the need for a ninth planet, it is the first such theory which is able to explain the significant features of the observed orbits while accounting for the mass and gravity of the other eight planets in our solar system.

White Dwarfs Have Solid Crystalline Cores Made of Oxygen and Carbon

Posted by Guy Pirro 01/15/2019 10:03AM

White Dwarfs Have Solid Crystalline Cores Made of Oxygen and Carbon

White dwarf stars are some of the oldest stellar objects in the universe. They are incredibly useful to astronomers, as their predictable lifecycle allows them to be used as cosmic clocks to estimate the age of groups of neighboring stars to a high degree of accuracy. White dwarfs are the remaining cores of red giants after these huge stars have died and shed their outer layers. As they cool, they release their stored up heat over the course of billions of years. Now, the first direct evidence of white dwarf stars cooling and solidifying into crystals has been discovered by astronomers at the University of Warwick in the UK… And it turns out that our skies are filled with them – White dwarfs made of solid oxygen and carbon formed through a phase transition process similar to when water turns into ice, but at much higher temperatures and pressures.

Kiss the Sky Tonight -- Month of January 2019

Posted by Guy Pirro 01/08/2019 12:48PM

Kiss the Sky Tonight -- Month of January 2019

Happy New Year and welcome to the night sky report for January 2019 -- Your guide to the constellations, deep sky objects, planets, and celestial events that are observable during the month. In January, the northern hemisphere features beautiful views of the binary star Capella - a pair of giant yellow stars, Aldebaran - a red giant star, two star clusters—the Hyades (Caldwell 41) and the Pleiades (M45), and the Crab Nebula (M1). The night sky is truly a celestial showcase. Get outside and explore its wonders from your own backyard.

The Falcon (New Horizons) and the Snowman (Ultima Thule)

Posted by Guy Pirro 01/03/2019 06:48PM

The Falcon (New Horizons) and the Snowman (Ultima Thule)

Following its successful fly-by of Pluto in July 2015, NASA's New Horizons mission has now performed a second fly-by – this time of an entirely new kind of world deep in the Kuiper Belt. NASA scientists released the first detailed images of the most distant object ever explored — the Kuiper Belt object Ultima Thule. Its remarkable appearance -- two spherical objects touching together in the shape of a snowman, unlike anything we've seen before -- sheds new light on the processes that built our Solar System planets four and a half billion years ago. New Horizon’s images of Ultima Thule unveil the very first stages of our Solar System's history.