The Milky Way’s outer reaches are coming into view thanks to the JWST. Astronomers pointed the powerful space telescope to a region over 58,000 light-years away called the Extreme Outer Galaxy (EOG). They found star clusters exhibiting extremely high rates of star formation.
Continue reading “The Outer Reaches of the Milky Way are Full of Stars, and the JWST is Observing Them”Webb Sees a Star in the Midst of Formation
Wherever the JWST looks in space, matter and energy are interacting in spectacular displays. The Webb reveals more detail in these interactions than any other telescope because it can see through dense gas and dust that cloak many objects.
In a new image, the JWST spots a young protostar only 100,000 years old.
Continue reading “Webb Sees a Star in the Midst of Formation”JWST Reveals a Newly-Forming Double Protostar
As our newest, most perceptive eye on the ongoing unfolding of the cosmos, the James Webb Space Telescope is revealing many things that were previously unseeable. One of the space telescope’s science goals is to expand our understanding of how stars form. The JWST has the power to see into the cocoons of gas and dust that hide young protostars.
It peered inside one of these cocoons and showed us that what we thought was a single star is actually a binary star.
Continue reading “JWST Reveals a Newly-Forming Double Protostar”This Dark Nebula Hides an Enormous Star
The birth of a star is a spectacular event that plays out behind a veil of gas and dust. It’s a detailed process that takes millions of years to play out. Once a star leaves its protostar stage behind and begins its life of fusion, the star’s powerful radiative output blows the veil away.
But before then, astrophysicists are at a disadvantage.
Continue reading “This Dark Nebula Hides an Enormous Star”It’s Like Looking at the Infant Sun: Webb Captures Image of an Energetic Young Star
Ever wondered what our young Sun might have looked like in its infancy some five billion years ago?
The audacious JWST has captured an image of a very young star much like our young Sun, though the star itself is obscured. Instead, we see supersonic jets of gas. Young stars can blast out jets of material as they form, and the jets light up the surrounding gas. The luminous regions created by the jets as they slam into the gas are called Herbig-Haro Objects.
Continue reading “It’s Like Looking at the Infant Sun: Webb Captures Image of an Energetic Young Star”Each Planetary Nebula is Unique. Why Do They Look So Different?
When it comes to cosmic eye candy, planetary nebulae are at the top of the candy bowl. Like fingerprints—or maybe fireworks displays—each one is different. What factors are at work to make them so unique from one another?
Continue reading “Each Planetary Nebula is Unique. Why Do They Look So Different?”New jets seen blasting out of the center of a galaxy
Giant black holes can launch jets that extend for tens of thousand of light-years, blasting clean out of their host galaxies. These jets can last for tens of millions of years. Recently astronomers have spotted the first-ever jet in the process of forming, creating a cavity in the span of only twenty years.
Continue reading “New jets seen blasting out of the center of a galaxy”This is an Actual Photograph of the Shock Waves from Supersonic Jets Interacting with Each Other
After more than 10 years of hard work, NASA has reached another milestone. We’re accustomed to NASA reaching milestones, but this one’s a little different. This one’s all about a type of photography that captures images of the flow of fluids.
Continue reading “This is an Actual Photograph of the Shock Waves from Supersonic Jets Interacting with Each Other”Rock Around the Comet Clock with Hubble
Remember 252P/LINEAR? This comet appeared low in the morning sky last month and for a short time grew bright enough to see with the naked eye from a dark site. 252P swept closest to Earth on March 21, passing just 3.3 million miles away or about 14 times the distance between our planet and the moon. Since then, it’s been gradually pulling away and fading though it remains bright enough to see in small telescope during late evening hours.
While amateurs set their clocks to catch the comet before dawn, astronomers using NASA’s Hubble Space Telescope captured close-up photos of it two weeks after closest approach. The images reveal a narrow, well-defined jet of dust ejected by the comet’s fragile, icy nucleus spinning like a water jet from a rotating lawn sprinkler. These observations also represent the closest celestial object Hubble has observed other than the moon.
Sunlight warms a comet’s nucleus, vaporizing ices below the surface. In a confined space, the pressure of the vapor builds and builds until it finds a crack or weakness in the comet’s crust and blasts into space like water from a whale’s blowhole. Dust and other gases go along for the ride. Some of the dust drifts back down to coat the surface, some into space to be shaped by the pressure of sunlight into a dust tail.
You can still see 252P/LINEAR if you have a 4-inch or larger telescope. Right now it’s a little brighter than magnitude +9 as it slowly arcs along the border of Ophiuchus and Hercules. With the moon getting brighter and brighter as it fills toward full, tonight and tomorrow night will be best for viewing the comet. After that you’re best to wait till after the May 21st full moon when darkness returns to the evening sky. 252P will spend much of the next couple weeks near the 3rd magnitude star Kappa Ophiuchi, a convenient guidepost for aiming your telescope in the comet’s direction.
While you probably won’t see any jets in amateur telescopes, they’re there all the same and helped created this comet’s distinctive and large, fuzzy coma. Happy hunting!
Enceladus’ Jets Selectively Power-Up Farther From Saturn
A crowning achievement of the Cassini mission to Saturn is the discovery of water vapor jets spraying out from Enceladus‘ southern pole. First witnessed by the spacecraft in 2005, these icy geysers propelled the little 515-kilometer-wide moon into the scientific spotlight and literally rewrote the mission’s objectives. After 22 flybys of Enceladus during its nearly twelve years in orbit around Saturn, Cassini has gathered enough data to determine that there is a global subsurface ocean of salty liquid water beneath Enceladus’ frozen crust—an ocean that gets sprayed into space from long “tiger stripe” fissures running across the moon’s southern pole. Now, new research has shown that at least some of the vapor jets get a boost in activity when Enceladus is farther from Saturn.
By measuring the changes in brightness of a distant background star as Enceladus’ plumes passed in front of it in March 2016, Cassini observed a significant increase in the amount of icy particles being ejected by one particular jet source.
Named “Baghdad 1,” the jet went from contributing 2% of the total vapor content of the entire plume area to 8% when Enceladus was at the farthest point in its slightly-eccentric orbit around Saturn. This small yet significant discovery indicates that, although Enceladus’ plumes are reacting to morphological changes to the moon’s crust due to tidal flexing, it’s select small-scale jets that are exhibiting the most variation in output (rather than a simple, general increase in outgassing across the full plumes.)
“How do the tiger stripe fissures respond to the push and pull of tidal forces as Enceladus goes around its orbit to explain this difference? We now have new clues!” said Candice Hansen, senior scientist at the Planetary Science Institute and lead planner of the study. “It may be that the individual jet sources along the tiger stripes have a particular shape or width that responds most strongly to the tidal forcing each orbit to boost more ice grains at this orbital longitude.”
The confirmation that Enceladus shows an increase in overall plume output at farther points from Saturn was first made in 2013.
Whether this new finding means that the internal structure of the fissures is different than what scientists have suspected or some other process is at work either within Enceladus or in its orbit around Saturn still remains to be determined.
“Since we can only see what’s going on above the surface, at the end of the day, it’s up to the modelers to take this data and figure out what’s going on underground,” said Hansen.
Sources: Planetary Science Institute and NASA/JPL