Jump to content

HubbleSite

Members
  • Posts

    1,236
  • Joined

  • Last visited

    Never

HubbleSite's Achievements

Grand Master

Grand Master (14/14)

  • Conversation Starter
  • First Post
  • Collaborator
  • Posting Machine Rare

Recent Badges

0

Reputation

  1. Forty years ago in 1981, the first space shuttle launched, the Voyager 2 space probe encountered Saturn, and in Baltimore, Maryland, the Space Telescope Science Institute (STScI) was founded. In that year, NASA selected a proposal by the Association of Universities for Research in Astronomy to establish STScI on the Johns Hopkins University Homewood campus. STScI began its life as the home of science operations for NASA’s Hubble Space Telescope. Since Hubble’s 1990 launch, the institute has processed and distributed Hubble’s data and shared Hubble’s images and discoveries with the world. As it celebrates its 40th anniversary, STScI is looking forward to the future and its added responsibilities for mission and science operations of NASA’s James Webb Space Telescope, as well as science operations for NASA’s Nancy Grace Roman Space Telescope. View the full article
  2. Inhabitants of our Milky Way galaxy living several billion years from now will have a markedly different-looking sky overhead. Two brilliant objects, each as bright as the full Moon or brighter, will drown out the stars with their radiance. These giant blazing light bulbs are a pair of quasars, brought to life by the collision of our Milky Way with the neighboring Andromeda galaxy. Quasars are ignited by monster black holes voraciously feeding on infalling matter, unleashing a torrent of radiation. The Milky Way and Andromeda have such black holes at their hearts, which are now sleeping giants. That is, until the big bang-up. The duo will be as deadly then as it is dazzling. Blistering radiation from the quasar pair might sterilize the surfaces of planets, wiping out innumerable extraterrestrial civilizations. This tale of "death star" dueling quasars looming in the sky might seem like a scene out of a science fiction movie. But the real universe is stranger than fiction. This is actually a story that played out between two pairs of galaxies that existed long ago and far away. The four galaxies, each containing a central, bright quasar, are in the process of merging. As the two galaxies in each quasar pair move closer together, so do their quasars. Hubble caught the action, photographing two quasar pairs that existed 10 billion years ago, during the peak epoch of galaxy close encounters. The discovery offers a unique way to probe collisions among galaxies in the early universe that might otherwise have gone undetected. Ancient quasars are scattered all across the heavens, so finding these dynamic duos is fortuitous. Astronomers estimate only one in a thousand quasars are really double quasars. View the full article
  3. The NHFP is one of the highlights of NASA's pursuit of excellence in astrophysics. The program enables outstanding postdoctoral scientists to pursue independent research in any area of NASA Astrophysics, using theory, observation, experimentation, or instrument development. Over 400 applicants vied for the fellowships. Each fellowship provides the awardee up to three years of support. View the full article
  4. Stars aren't shy about announcing their births. As they are born from the collapse of giant clouds of hydrogen gas and begin to grow, they launch hurricane-like winds and spinning, lawn-sprinkler-style jets shooting off in opposite directions. This action carves out huge cavities in the giant gas clouds. Astronomers thought these stellar temper tantrums would eventually clear out the surrounding gas cloud, halting the star's growth. But in a comprehensive analysis of 304 fledgling stars in the Orion Complex, the nearest major star-forming region to Earth, researchers discovered that gas-clearing by a star's outflow may not be as important in determining its final mass as conventional theories suggest. Their study was based on previously collected data from NASA's Hubble and Spitzer space telescopes and the European Space Agency's Herschel Space Telescope. The study leaves astronomers still wondering why star formation is so inefficient. Only 30% of a hydrogen gas cloud's initial mass winds up as a newborn star. View the full article
  5. The Wide Field Camera 3 (WFC3) instrument on NASA's Hubble Space Telescope was brought back online on Saturday, March 13th at approximately 7:00 p.m. EST. The instrument was shut down as part of the normal observatory safe mode activities that occurred on Sunday, March 7, in response to a software error on the main flight computer. After starting its recovery on Thursday, March 11, WFC3 suspended the process due to a slightly lower-than-normal voltage reading for a power supply, which triggered an internal instrument safeguard. View the full article
  6. NASA is working to return the Hubble Space Telescope to science operations after resolving a problem with a safeguard aboard. Hubble entered safe mode on Sunday, March 7, shortly after 4 a.m. EST, following detection of a software error within the spacecraft’s main computer. The spacecraft has been moved out of safe mode into a pre-science state with the plan of returning to normal operations by Thursday night. View the full article
  7. Orbiting a red dwarf star 41 light-years away is an Earth-sized, rocky exoplanet called GJ 1132 b. In some ways, GJ 1132 b has intriguing parallels to Earth, but in other ways it is very different. One of the differences is that its smoggy, hazy atmosphere contains a toxic mix of hydrogen, methane and hydrogen cyanide. Scientists using NASA's Hubble Space Telescope have found evidence this is not the planet's original atmosphere, and that the first one was blasted away by blistering radiation from GJ 1132 b's nearby parent star. The so-called "secondary atmosphere" is thought to be formed as molten lava beneath the planet's surface continually oozes up through volcanic fissures. Gases seeping through these cracks seem to be constantly replenishing the atmosphere, which would otherwise also be stripped away by the star. This is the first time a secondary atmosphere has been detected on a world outside our solar system. View the full article
  8. Orbiting a red dwarf star 41 light-years away is an Earth-sized, rocky exoplanet called GJ 1132 b. In some ways, GJ 1132 b has intriguing parallels to Earth, but in other ways it is very different. One of the differences is that its smoggy, hazy atmosphere contains a toxic mix of hydrogen, methane and hydrogen cyanide. Scientists using NASA's Hubble Space Telescope have found evidence this is not the planet's original atmosphere, and that the first one was blasted away by blistering radiation from GJ 1132 b's nearby parent star. The so-called "secondary atmosphere" is thought to be formed as molten lava beneath the planet's surface continually oozes up through volcanic fissures. Gases seeping through these cracks seem to be constantly replenishing the atmosphere, which would otherwise also be stripped away by the star. This is the first time a secondary atmosphere has been detected on a world outside our solar system. View the full article
  9. Stars come in an extraordinary range of sizes. One of the most colossal is VY Canis Majoris. If placed in the middle of our solar system it would engulf all the planets out to Saturn's orbit. This monster, appropriately called a red hypergiant, is as bright as 300,000 Suns. Yet it is so far away that, 200 years ago, it could be seen only as a faint star in the winter constellation of the Great Dog. Since then, it has faded and is no longer visible to the naked eye. Astronomers used Hubble to get a close-up look at the star and discovered the reason for the dimming. The star is expelling huge clouds of dust in the final stages of its life. Eventually, the bloated star may explode as a supernova, or may simply collapse and form a black hole. View the full article
  10. Long road trips can be tedious and boring. That's why many road travelers break up their arduous journey by making rest stops along the way. Astronomers found that at least one roaming comet is doing the same thing. The wayward object made a temporary stop near giant Jupiter. The icy visitor has plenty of company: It has settled near the family of captured asteroids known as Trojans that are co-orbiting the Sun alongside Jupiter. This is the first time a comet-like object has been spotted near the Trojan asteroid population. Hubble Space Telescope observations reveal the vagabond is showing signs of transitioning from a frigid asteroid-like body to an active comet, sprouting a long tail, outgassing jets of material, and enshrouding itself in a coma of dust and gas. The interloper came from the frigid outskirts of our solar system, a comet nesting-ground called the Kuiper Belt. This nomad was likely snatched by Jupiter's powerful gravity after it had a brush with the giant planet. Jupiter's uninvited guest probably will not hang around the planet for very long. As the "bouncer" of the solar system, the monster planet's gravitational tug will eventually boot the comet back onto its road trip toward our Sun. View the full article
  11. The idea that black holes come in different sizes may sound a little odd at first. After all, a black hole by definition is an object that has collapsed under gravity to an infinite density, making it smaller than the period at the end of this sentence. But the amount of mass a black hole can pack away varies widely from less than twice the mass of our Sun to over a billion times our Sun's mass. Midway between are intermediate-mass black holes (IMBHs) weighing roughly hundreds to tens of thousands of solar masses. So, black holes come small, medium, and large. However, the IMBHs have been elusive. They are predicted to hide out in the centers of globular star clusters, beehive-shaped swarms of as many as a million stars. Hubble researchers went hunting for an IMBH in the nearby globular cluster NGC 6397 and came up with a surprise. Because a black hole cannot be seen, they carefully studied the motion of stars inside the cluster, that would be gravitationally affected by the black hole's gravitational tug. The amplitudes and shapes of the stellar orbits led to the conclusion that there is not just one hefty black hole, but a swarm of smaller black holes – a mini-cluster in the core of the globular. Why are the black holes hanging out together? A gravitational pinball game takes place inside globular clusters where more massive objects sink to the center by exchanging momentum with smaller stars, that then migrate to the cluster's periphery. The central black holes may eventually merge, sending ripples across space as gravitational waves. View the full article
  12. Sometime during the third century, a brilliant burst of light from the explosion of a massive star was visible from Earth. If the supernova blast had flashed over the northern hemisphere, it might have been considered an evil omen. At that time, Western Civilization was in upheaval. The Roman Empire was beginning to crumble. An emperor was assassinated, followed by political upheavals, civil wars, and barbarian attacks. But the violent supernova death could only be seen in the southern skies. The blast occurred in the nearby satellite galaxy, the Small Magellanic Cloud. No record exists of the titanic event. However, like the smoke and ash drifting across the sky after an aerial fireworks blast, the supernova left behind a cloud of debris that is still rapidly expanding today. This cloud provides forensic evidence for astronomical detectives to retrace the explosion. Astronomers sifting through Hubble observations of the supernova remnant, taken 10 years apart, have calculated the cloud's expansion rate. Analyzing the data was like rewinding a movie. The researchers traced the path of all the debris flung from the explosion back to the point in space where the doomed star blew apart. Their analysis reveals that the light from the exploded star reached Earth 1,700 years ago. View the full article
  13. How dark is the sky, and what does that tell us about the number of galaxies in the visible universe? Astronomers can estimate the total number of galaxies by counting everything visible in a Hubble deep field and then multiplying them by the total area of the sky. But other galaxies are too faint and distant to directly detect. Yet while we can’t count them, their light suffuses space with a feeble glow. To measure that glow, astronomers have to escape the inner solar system and its light pollution, caused by sunlight reflecting off dust. A team of scientists has used observations by NASA’s New Horizons mission to Pluto and the Kuiper Belt to determine the brightness of this cosmic optical background. Their result sets an upper limit to the starlight emitted by faint, unresolved galaxies, showing that there is about twice as much optical light permeating space as can be accounted for by all known galaxies. View the full article
  14. In 1995, the Hubble Space Telescope stared at a blank patch of the sky for 10 straight days. The resulting Deep Field image captured thousands of previously unseen, distant galaxies. Similar observations have followed since then, including the longest and deepest exposure, the Hubble Ultra Deep Field. Now, astronomers are looking ahead to the future, and the possibilities enabled by NASA’s upcoming Nancy Grace Roman Space Telescope. The Roman Space Telescope will be able to photograph an area of sky 100 times larger than Hubble with the same exquisite sharpness. As a result, a Roman Ultra Deep Field would collect millions of galaxies, including hundreds that date back to just a few hundred million years after the big bang. Such an observation would fuel new investigations into multiple science areas, from the structure and evolution of the universe to star formation over cosmic time. View the full article
  15. When NASA's Voyager 2 spacecraft flew by Neptune in 1989 after a nearly 3-billion-mile odyssey, astronomers expected to get a close-up look at a blue-green planet that seemed as featureless as a marble. Instead, they were shocked and intrigued to see a dynamic and turbulent world of whirling storms, including a giant feature dubbed the Great Dark Spot, looming in Neptune's far southern hemisphere. The vortex was reminiscent of Jupiter's legendary Great Red Spot, a monstrous storm that has been raging for hundreds of years. Had this Great Dark Spot been brewing for the same amount of time? Or, was it a more ephemeral tempest? Scientists had to wait until 1994, when the Hubble Space Telescope and its crisp vision peered at distant Neptune. The mysterious spot had vanished! This game of planetary peek-a-boo continued when Hubble spotted another dark storm appearing in Neptune's northern hemisphere in 1995. Over the past three decades, Hubble has continued to observe the planet, watching several more dark spots come and go. Only Hubble can study these spots because it has the sharp vision to observe them in visible light. Hubble has shown that these storms live for a few years before vanishing or fading away. Researchers thought the current giant storm in the northern hemisphere was heading to destruction when it mysteriously halted its southern journey and began drifting northward. At the same time as the spot's stunning reversal, a new, slightly smaller dark feature appeared near its bigger cousin and later disappeared. These surprising events add to the mystery of this dynamic world. View the full article
×
×
  • Create New...