Noctilucent clouds were once thought to be a fairly modern phenomenon. A team of researcher have recently calculated that Earth and the entire Solar System may well have passed through two dense interstellar clouds causing global noctilucent clouds that may have driven an ice age. The event is thought to have happened 7 million years ago and would have compressed the heliosphere, exposing Earth to the interstellar medium.
Continue reading “What Happens to the Climate When Earth Passes Through Interstellar Clouds?”The Nearby Star Clusters Come from Only Three Places
Many astronomy-interested people know of the Hyades and the Pleiades. They’re star clusters in the Taurus constellation. They’re two out of a handful of star clusters that are visible to the unaided eye under dark sky conditions.
It turns out that these clusters, along with more than 150 other nearby clusters, all originated in only three massive star-forming regions.
Continue reading “The Nearby Star Clusters Come from Only Three Places”Was Earth’s Climate Affected by Interstellar Clouds?
Scientists scour the Earth and the sky for clues to our planet’s climate history. Powerful and sustained volcanic eruptions can alter the climate for long periods of time, and the Sun’s output can shift Earth’s climate over millions of years.
But what about interstellar hydrogen clouds? Can these regions of gas and dust change Earth’s climate when the planet encounters them?
Continue reading “Was Earth’s Climate Affected by Interstellar Clouds?”Want to Leave the Solar System? Here’s a Route to Take
The edge of the Solar System is defined by the heliosphere and its heliopause. The heliopause marks the region where the interstellar medium stops the outgoing solar wind. But only two spacecraft, Voyager 1 and Voyager 2, have ever travelled to the heliopause. As a result, scientists are uncertain about the heliopause’s extent and its other properties.
Some scientists are keen to learn more about this region and are developing a mission concept to explore it.
Continue reading “Want to Leave the Solar System? Here’s a Route to Take”Astronomers Build a 3D Map of Dust Within Thousands of Light-Years
If you explore the night sky it won’t be long before you realise there is a lot of dust and gas up there. The interstellar dust between the stars accounts for 1% of the mass of the interstellar medium but reflects 30% of the starlight in infrared wavelengths. The dust plays a key role in the formation of stars and the evolution of the Galaxy. A team of astronomers have attempted to map the dust out to a distance of 3000 light years and have just released the first 3D map of the dust in our Galaxy.
Continue reading “Astronomers Build a 3D Map of Dust Within Thousands of Light-Years”Twinkling Stars Supply the Dust That Leads to Life
When low to medium-mass stars exhaust their supply of hydrogen, they exit their main sequence phase and expand to become red giants – what is known as the Asymptotic Giant Branch (AGB) phase. Stars in this phase of their evolution become variable (experiences changes in brightness) to shed their outer lays, spreading dust throughout the interstellar medium (ISM) that is crucial to the development of planetary nebulas and protoplanetary systems. For decades, astronomers have sought to better understand the role Red Giant stars play.
Studying interstellar and protoplanetary dust is difficult because it is so faint in visible light. Luckily, this dust absorbs light and radiates brightly in the infrared (IR), making it visible to IR telescopes. Using archival data from now-retired Akari and Wide-field Infrared Survey Explorer (WISE) missions, a team of Japanese astronomers conducted the first long-period survey of dusty AGBs and observed that the variable intensity of these stars coincides with the amount of dust they produce. Since this dust plays an important role in the formation of planets, this study could shed light on the origins of life.
Continue reading “Twinkling Stars Supply the Dust That Leads to Life”Astronomers use the World's Biggest Radio Telescope to map new Features of the Milky Way
Despite everything astronomers have learned about the nature and structure of galaxies, there are still mysteries about the Milky Way. The reason for this is simple: since we are embedded in the Milky Way’s disk, we have difficulty mapping it and observing it as a whole. It’s also very challenging to observe the center of the galaxy, what lies beyond it, and features in the disk itself because of all the gas and dust between stars- the Interstellar Medium (ISM). However, by observing the Milky Way in the non-visible spectrum (radio, x-ray, gamma-ray, etc.), astronomers can see more of what’s out there.
There’s also the spectral line that corresponds to the emission frequency (1420 MHz) of cold neutral hydrogen gas (HI), which makes up the majority of the ISM. Using the Five-hundred-meter Aperture Spherical Telescope (FAST) – the most powerful radio telescope in the world near Guizhou, China – a team of scientists located more than 500 new faint pulsars. During the survey, the team simultaneously recorded the spectral line data with high spectral and spatial resolution, making it an extremely valuable resource for studying the structure of the Milky Way Galaxy and the life cycle of its stars.
Continue reading “Astronomers use the World's Biggest Radio Telescope to map new Features of the Milky Way”One of Life’s Building Blocks can Form in Space
Peptides are one of the smallest biomolecules and are one of life’s critical building blocks. New research shows that they could form on the surfaces of icy grains in space. This discovery lends credence to the idea that meteoroids, asteroids, or comets could have given life on Earth a kick start by crashing into the planet and delivering biological building blocks.
Continue reading “One of Life’s Building Blocks can Form in Space”Nearby Supernovae Exploded Just a few Million Years Ago, Leading to a Wave of Star Formation Around the Sun
The Sun isn’t the only star in this galactic neighbourhood. Other stars also call this neighbourhood home. But what’s the neighbourhood’s history? What triggered the birth of all those stars?
A team of astronomers say they’ve pieced the history together and identified the trigger: a series of supernovae explosions that began about 14 million years ago.
Continue reading “Nearby Supernovae Exploded Just a few Million Years Ago, Leading to a Wave of Star Formation Around the Sun”NASA is now Planning a Mission to go 1,000 AU From the Sun, Deep Into Interstellar Space
A different perspective can do wonders. Perceiving things from a different angle can both metaphorically and literally allow people to see things differently. And in space, there are an almost infinite number of angles that objects can be observed from. Like all perspectives, some are more informative than others. Sometimes those informative perspectives are also the hardest to reach.
Voyager’s two probes did an excellent job in allowing humanity to access some difficult new perspectives simply given their distance from the Earth. But now a team of over 500 scientists and volunteers is urging NASA to go even further to find a better perspective by sending a satellite to a distance 1000 times the distance from the Sun to the Earth – almost 10 times how far the Voyagers have traveled in over 35 years.
Continue reading “NASA is now Planning a Mission to go 1,000 AU From the Sun, Deep Into Interstellar Space”