Hubble in safe mode, down to two gyroscopes

The end might be near: The Hubble Space Telescope went into safe mode this weekend when one of its three working gyroscopes failed.

Hubble has six gyroscopes, all of which were replaced by spacewalking astronauts during a servicing mission in May 2009. The telescope needs three working gyroscopes to “ensure optimal efficiency,” mission team members have written, and the failure brings that number down to two (if the “problematic” one that had been off can’t be brought back online).

But that doesn’t mean it’s time to panic. Hubble can do good science with two gyroscopes, or even one, astrophysicist Grant Tremblay, of the Harvard-Smithsonian Center for Astrophysics, said via Twitter Sunday.

While it is true that Hubble can do science on one or two gyroscopes, in that mode it will no longer be able to take the sharp spectacular pictures that represent its great glory.

Hubble was launched in 1990, fixed in 1993, and has been the most successful science robot ever launched. Scientists had hoped, when they made the James Webb Space Telescope their priority in the very early 2000s that both would be in space and operating to provide top notch science data, with Hubble working in visible wavelengths and Webb in the infrared. Webb’s endless delays and cost overruns has now probably made that impossible.

Worse, there are no plans to build a replacement for Hubble. For the first time since 1993, the human race will no longer be able to see, with our own eyes, the universe sharply.

The aurora of Saturn

Cool movie time! Using the Hubble space telescope scientists have compiled an animation showing the changes in Saturn’s north pole aurora over time.

In 2017, over a period of seven months, the NASA/ESA Hubble Space Telescope took images of auroras above Saturn’s north pole region using the Space Telescope Imaging Spectrograph. The observations were taken before and after the Saturnian northern summer solstice. These conditions provided the best achievable viewing of the northern auroral region for Hubble.

…The images show a rich variety of emissions with highly variable localized features. The variability of the auroras is influenced by both the solar wind and the rapid rotation of Saturn, which lasts only about 11 hours. On top of this, the northern aurora displays two distinct peaks in brightness — at dawn and just before midnight. The latter peak, unreported before, seems specific to the interaction of the solar wind with the magnetosphere at Saturn’s solstice.

The animation of all the images is embedded below. At the link is a second video showing the aurora in close-up

Chandra looks back at the Crab Nebula

Link here. It is almost twenty years since the Chandra X-Ray Observatory was launched, and in celebration the science team have released another X-ray image of the Crab Nebula, taken in 2017 in league with an optical image from the Hubble Space Telescope and an infrared image from the Spitzer Space Telescope. They have also provided links to all similar past images, going back to 1999.

Some of the images are actually videos, in 2002 and 2011, showing the Crab’s dynamic nature. You can actually see flares and waves of radiation rippling out from its center.

Hubble finds new figure for universe expansion rate

The uncertainty of science: Using data from the Hubble Space Telescope astronomers have found evidence that universe’s expansion rate is faster than estimated in previous measurements.

The new findings show that eight Cepheid variables in our Milky Way galaxy are up to 10 times farther away than any previously analyzed star of this kind. Those Cepheids are more challenging to measure than others because they reside between 6,000 and 12,000 light-years from Earth. To handle that distance, the researchers developed a new scanning technique that allowed the Hubble Space Telescope to periodically measure a star’s position at a rate of 1,000 times per minute, thus increasing the accuracy of the stars’ true brightness and distance, according to the statement.

The researchers compared their findings to earlier data from the European Space Agency’s (ESA) Planck satellite. During its four-year mission, the Planck satellite mapped leftover radiation from the Big Bang, also known as the cosmic microwave background. The Planck data revealed a Hubble constant between 67 and 69 kilometers per second per megaparsec. (A megaparsec is roughly 3 million light-years.)

However, the Planck data gives a constant about 9 percent lower than that of the new Hubble measurements, which estimate that the universe is expanding at 73 kilometers per second per megaparsec, therefore suggesting that galaxies are moving faster than expected, according to the statement.

“Both results have been tested multiple ways, so barring a series of unrelated mistakes, it is increasingly likely that this is not a bug but a feature of the universe,” Riess said. [emphasis mine]

I should point out that one of the first big results from Hubble in 1995 (which also happened to be the subject one of my early published stories), the estimate then for the Hubble constant was 80 kilometers per second per megaparsec. At the time, the astronomers who did the research were very certain they had it right. Others have theorized that the number could be as low as 30 kilometers per second per megaparsec.

What is important about this number is that it determines how long ago the Big Bang is thought to have occurred. Lower numbers mean it took place farther in the past. Higher numbers mean the universe is very young.

That scientists keep getting different results only suggests to me that they simply do not yet have enough data to lock the number down firmly.

Hubble spots most distance active comet yet

Comet C/2017 K2

Using the Hubble Space Telescope astronomers have imaged a comet that is sublimating material at a distance from the Sun farther than any previously known comet, out beyond Saturn.

“K2 is so far from the Sun and so cold, we know for sure that the activity — all the fuzzy stuff making it look like a comet — is not produced, as in other comets, by the evaporation of water ice,” said lead researcher David Jewitt of the University of California, Los Angeles. “Instead, we think the activity is due to the sublimation [a solid changing directly into a gas] of super-volatiles as K2 makes its maiden entry into the solar system’s planetary zone. That’s why it’s special. This comet is so far away and so incredibly cold that water ice there is frozen like a rock.”

Based on the Hubble observations of K2’s coma, Jewitt suggests that sunlight is heating frozen volatile gases – such as oxygen, nitrogen, carbon dioxide, and carbon monoxide – that coat the comet’s frigid surface. These icy volatiles lift off from the comet and release dust, forming the coma. Past studies of the composition of comets near the Sun have revealed the same mixture of volatile ices.

The significance here is that by studying the comet’s activity scientists will be able to identify some of these volatile gases, which in turn will tell them something about the make-up of the outermost fringes of the solar system.

Have astronomers using Kepler discovered the first exomoon?

The uncertainty of science: Using data from Kepler astronomers think they have spotted the first exomoon, orbiting a star 4,000 light years away.

They think it might be the size of Neptune, and orbits a planet about ten times more massive than Jupiter.

All this is unconfirmed, however, especially because their conclusions are based on data from only three transits. They plan to use the Hubble Space Telescope to do more observations and hopefully confirm the discovery.

Hubble shoots movie of Phobos

Phobos over Mars

Cool image time! By taking a quick series of thirteen images, the Hubble Space Telescope was able to shoot a short movie of the rotation of Phobos above the surface of Mars. The gif animation on the right is the smaller of the two animations released today. Be sure and view the full resolution version.

What is even cooler is that movie was apparently unplanned. From the link:

Over the course of 22 minutes, Hubble took 13 separate exposures, allowing astronomers to create a time-lapse video showing the diminutive moon’s orbital path. The Hubble observations were intended to photograph Mars, and the moon’s cameo appearance was a bonus.

In terms of science this movie has a somewhat limited value. In terms of space engineering it is triumph, and once again illustrates the unprecedented value of having an optical telescope in space. Woe to us all when Hubble finally dies, as we have no plans to replace it.

Hubble snaps close-up of Jupiter

Jupiter by Hubble

Cool image time! The Hubble Space Telescope has taken a magnificent global view of Jupiter. The image on the right is only a thumbnail. Make sure to go to the link to see the full image, which amazingly compares quite favorably with the images being sent down by Juno in orbit around the gas giant.

This Hubble image once again demonstrates the remarkable advantages of an optical telescope in space. Equipped with the right instruments, it could do much of the research now being done by the planetary missions, and do it from Earth orbit.The research possibilities and the knowledge revealed from the ability to see things clearly in the optical bands is truly endless.

Even more important, we are wired to what we see. Give us a good visual image and many questions can immediately be answered.

Hubble takes a look at both Voyagers’ interstellar path

Using the Hubble Space Telescope astronomers have taken a peek at the interstellar material that the two Voyager spacecraft will travel through as they move out and leave the solar system in the coming decades.

Voyager 1 is 13 billion miles from Earth, making it the farthest human-made object ever built. In about 40,000 years, after the spacecraft will no longer be operational and will not be able to gather new data, it will pass within 1.6 light-years of the star Gliese 445, in the constellation Camelopardalis. Its twin, Voyager 2, is 10.5 billion miles from Earth, and will pass 1.7 light-years from the star Ross 248 in about 40,000 years.

For the next 10 years, the Voyagers will be making measurements of interstellar material, magnetic fields, and cosmic rays along their trajectories. Hubble complements the Voyagers’ observations by gazing at two sight lines along each spacecraft’s path to map interstellar structure along their star-bound routes. Each sight line stretches several light-years to nearby stars. Sampling the light from those stars, Hubble’s Space Telescope Imaging Spectrograph measured how interstellar material absorbed some of the starlight, leaving telltale spectral fingerprints.

Hubble found that Voyager 2 will move out of the interstellar cloud that surrounds the solar system in a couple thousand years. The astronomers, based on Hubble data, predict that the spacecraft will spend 90,000 years in a second cloud before passing into a third interstellar cloud.

This is very clever science. It allows data from Hubble to complement the data from the two Voyager spacecraft to better understand the interstellar regions that surround our solar system.

Hubble captures on-going comet break-up

animation of comet debris

Cool image time! The animation to the right, taken over three days by the Hubble Space Telescope, cropped and reduced to fit here, shows the debris flying away from Comet 332P/Ikeya-Murakami. It also shows a new piece of debris close to the comet on the lower left.

The research team calculated that the comet probably shed material over several months, between October and December 2015. Jewitt suggests that even some of the ejected pieces have themselves fallen to bits in a kind of cascading fragmentation. “Our analysis shows that the smaller fragments are not as abundant as one might expect based on the number of bigger chunks,” he said. “This is suggestive that they’re being depleted even in the few months since they were launched from the primary body. We think these little guys have a short lifetime.”

Hubble’s sharp vision also spied a chunk of material close to the comet, which may be the first salvo of another outburst. The remnant from still another flare-up, which may have occurred in 2012, is also visible. The fragment may be as large as Comet 332P, suggesting the comet split in two. But the icy remnant wasn’t spotted until Dec. 31, 2015, by the Pan-STARRS (Panoramic Survey Telescope and Rapid Response System) telescope in Hawaii, in work supported by the Near-Earth Object Observations program in NASA’s Planetary Defense Coordination Office. That discovery prompted Jewitt and colleagues to request Hubble time to look at the comet in detail. Around the same time, astronomers around the world began to notice a cloudy patch of material near the comet – which Hubble later resolved into the 25 pieces.

The scientists think they actually “may be seeing a comet fragmenting itself into oblivion.”

NASA extends Hubble contract through 2021

NASA has extended its contract with Lockheed Martin for the operation of the Hubble Space Telescope until June 2021.

This contract is for non-science operations. Science operations are controlled by the Space Telescope Science Institute in Baltimore.

Note that when the last repair mission to Hubble took place in 2009, they expected it to add five years to the telescope’s life. This contract says they now expect it to last at least until 2021, which will also be 31 years after its launch and almost forty years since its actual construction. Not a bad track record when you think about it, especially since its original mission was set at 15 years, ending in 2005.

New Hubble image of Crab Nebula

Crab Nebula

Cool image time! Scientists have released a new Hubble Space Telescope image taken of the innermost regions of the Crab Nebula, the remains of a supernova explosion that took place a thousand years ago in 1054.

On the right is a reduced resolution version of this new image. I have also cropped it to focus on the nebula’s center, where the pulsar is located. The circular concentric rings are exactly what they appear to be, ripples of energy spreading out from the pulsar. Back in 2002 Hubble took a series of images of the Crab Nebula over several days, which scientists then assembled into a movie showing these waves as they emanated out from the nebula’s center.

My only complaint with this beautiful new image is that they did not take a longer series of new exposures to create a longer movie, to better show the actual daily changes that the nebula undergoes. It seemed obvious to do then, and obvious to do now. Yet, it hasn’t happened.

The image download page for today’s release is here.

Hubble images Jupiter and its aurora

Jupiter and its aurora

Cool image time! In anticipation of the arrival of Juno in orbit around Jupiter on July 4, scientists have released a spectacular image of Jupiter and its aurora, taken by the Hubble Space Telescope. The image on the right has been reduced slightly to fit on the webpage.

The main focus of the imaging is the aurora.

To highlight changes in the auroras, Hubble is observing Jupiter almost daily for several months. Using this series of far-ultraviolet images from Hubble’s Space Telescope Imaging Spectrograph, it is possible for scientists to create videos that demonstrate the movement of the vivid auroras, which cover areas bigger than the Earth.

Not only are the auroras huge in size, they are also hundreds of times more energetic than auroras on Earth. And, unlike those on Earth, they never cease. While on Earth the most intense auroras are caused by solar storms — when charged particles rain down on the upper atmosphere, excite gases, and cause them to glow red, green, and purple — Jupiter has an additional source for its auroras.

The strong magnetic field of the gas giant grabs charged particles from its surroundings. This includes not only the charged particles within the solar wind, but also the particles thrown into space by its orbiting moon Io, known for its numerous and large volcanos.

I have embedded below the fold one of the videos of the aurora, taken over time by Hubble. Quite amazing.
» Read more

Hubble spots new dark storm on Neptune

The Hubble Space Telescope has imaged a developing new dark spot storm on Neptune.

New images obtained on May 16, 2016, by NASA’s Hubble Space Telescope confirm the presence of a dark vortex in the atmosphere of Neptune. Though similar features were seen during the Voyager 2 flyby of Neptune in 1989 and by the Hubble Space Telescope in 1994, this vortex is the first one observed on Neptune in the 21st century. The discovery was announced on May 17, 2016, in a Central Bureau for Astronomical Telegrams (CBAT) electronic telegram by University of California at Berkeley research astronomer Mike Wong, who led the team that analyzed the Hubble data.

Hubble discovers moon circling Kuiper belt object

Worlds without end: Hubble has spotted a small moon orbiting the distant Kuiper Belt object Makemake.

The moon — provisionally designated S/2015 (136472) 1 and nicknamed MK 2 — is more than 1,300 times fainter than Makemake. MK 2 was seen approximately 13,000 miles from the dwarf planet, and its diameter is estimated to be 100 miles across. Makemake is 870 miles wide. The dwarf planet, discovered in 2005, is named for a creation deity of the Rapa Nui people of Easter Island.

New weather maps of Jupiter

Using the Hubble Space Telescope astronomers have compiled a new set of maps of Jupiter, showing changes in the gas giant’s bands and spots, including the Giant Red Spot.

The scientists behind the new images took pictures of Jupiter using Hubble’s Wide Field Camera 3 over a ten-hour period and have produced two maps of the entire planet from the observations. These maps make it possible to determine the speeds of Jupiter’s winds, to identify different phenomena in its atmosphere and to track changes in its most famous features.

The new images confirm that the huge storm, which has raged on Jupiter’s surface for at least three hundred years, continues to shrink, but that it may not go out without a fight. The storm, known as the Great Red Spot, is seen here swirling at the centre of the image of the planet. It has been decreasing in size at a noticeably faster rate from year to year for some time. But now, the rate of shrinkage seems to be slowing again, even though the spot is still about 240 kilometres smaller than it was in 2014.

Astronomers propose giant super Hubble replacement

A major university consortium that manages many ground- and space-based telescopes has proposed that a new giant optical space telescope be built to replace Hubble.

A report published today by the Association of Universities for Research in Astronomy in Washington, D.C., lays out the rationale for another orbiting observatory. It will have a mirror as big as 12 meters across, to both look for habitable planets around other stars and peer deep into the early aeons of the universe.

Hubble has a mirror 2.4 meters across, so this would be significantly larger. In fact, if built this new space telescope would make it bigger than any ground-based telescope that exists today.

As the article notes, the cost over-runs and delays of the infrared James Webb Space Telescope — which went from a $1 billion budget to $8 billion — will likely make Congress reluctant to fund a new giant project like this. Nonetheless, this report gives us a hint of where the astronomy community wants to head in future decades. For the past two decades they have poo-pooed the construction of a new and larger optical space telescope. It appears from this report that this culture is now changing.

Hubble films of movie of a jet firing from a black hole

Cool image time! Using images taken by the Hubble Space Telescope over the past two decades astronomers have assembled a movie of the motion of blobs, ejected by a jet from a supermassive black hole at the center of a galaxy.

The jet from NGC 3862 has a string-of-pearls structure of glowing knots of material. Taking advantage of Hubble’s sharp resolution and long-term optical stability, Eileen Meyer of the Space Telescope Science Institute (STScI) in Baltimore, Maryland, matched archival Hubble images with a new, deep image taken in 2014 to better understand jet motions. Meyer was surprised to see a fast knot with an apparent speed of seven times the speed of light catch up with the end of a slower moving, but still superluminal, knot along the string. The resulting “shock collision” caused the merging blobs to brighten significantly.

The movie is below the fold.
» Read more

Hubble finds something astronomers can’t explain

The uncertainty of science: The Hubble Space Telescope has spotted the explosion of a star that does not fit into any theory for stellar evolution.

The exploding star, which was seen in the constellation Eridanus, faded over two weeks — much too rapidly to qualify as a supernova. The outburst was also about ten times fainter than most supernovae, explosions that destroy some or all of a star. But it was about 100 times brighter than an ordinary nova, which is a type of surface explosion that leaves a star intact. “The combination of properties is puzzling,” says Mario Livio, an astrophysicist at the Space Telescope Science Institute in Baltimore, Maryland. “I thought about a number of possibilities, but each of them fails” to account for all characteristics of the outburst, he adds.

We can put this discovery on the bottom of a very long list of similar discoveries by Hubble, which this week is celebrating the 25th anniversary of its launch.

On that note, as part of that celebration Space.com today has published a long interview with me about Hubble and my book, The Universe in a Mirror, the saga of the Hubble Space Telescope and the visionaries who built it. They have also published an excerpt from the book. Check both out.

The Hubble Space Telescope lives on!

At a press conference at the January meeting of the American Astronomical Society scientists and engineers of the Space Telescope Science Institute that operates the Hubble Space Telescope reported that it is functioning far better than expected and is likely to continue to function until 2020 or beyond.

This is good news, since there is nothing being planned to replace Hubble. The article implies that the James Webb Space Telescope has that job, but Webb is an infrared telescope, not optical, and thus observes the universe in wavelengths not visible to the human eye.

New Hubble images to celebrate its upcoming 25th anniversary

The Space Telescope Science Institute (STScI) that operates the Hubble Space Telescope yesterday released two spectacular new images at the January meeting of the American Astronomical Society.

They also announced new data from Hubble that suggests a major eruption had occurred at the center of the Milky Way about two million years ago.

Eta Carinae’s next big show

Astronomers are gearing up to observe the next binary fly-by of Eta Carinae’s companion star over the next few weeks.

A binary system, η Carinae has two stars that swing past one another every 5.5 years. The bigger star — some 90 times the mass of the Sun — is incredibly unstable, always seemingly on the verge of blowing up. When the smaller companion star makes its closest approach to the primary star, as is happening now, the interaction between the two triggers violent changes in the high-energy radiation pouring out of the system.

Astronomers are watching the show in the hope of learning what drives this enigmatic system. In the 1840s, η Carinae had a mysterious eruption; in recent decades, it has again brightened unexpectedly. “The star is in an awfully deranged state, and no one knows why,” says Kris Davidson, an astronomer at the University of Minnesota in Minneapolis.

Eta Carinae is also famous because it was one of the first objects imaged by Hubble after its repair in 1993, and was thus the first stellar explosion ever caught on camera in a visually sharp and clear manner. (See my book The Universe in a Mirror for that fascinating story.)

A Hubble Space Telescope status report

Five years after the last shuttle repair mission, the Hubble Space Telescope continues to operate almost perfectly.

Jeletic said other than a single gyro failure, the observatory is operating in near-flawless fashion five years after the final shuttle crew departed. “Batteries are fine, solar arrays are fine, all the communications equipment is fine, we don’t see any glitches with the computers, the instruments are all fine,” he said. “In fact, an interesting statistic, the Advanced Camera for Surveys, which was repaired by the astronauts during the last servicing mission, that’s actually now run longer on the repair than it did originally for the Wide Field Camera part of it.”

The ACS, like the repaired Space Telescope Imaging Spectrograph, no longer has any internal redundancy. “It’s amazing. It truly is,” Jeletic said. “Given all the things that can fail, a lot of people were hoping for one or two years of continued work with it. Now we’ve gotten over five.” Likewise, the Space Telescope Imaging Spectrograph, which also is operating in “single-string” mode, is still going strong.

When they completed the 2009 servicing mission, the goal was to give Hubble five more years of operation. They’ve done that, and are now looking to keep the telescope going till at least 2020, marking 30 years in orbit.

The only issue, not surprisingly, is the failure of one of the six gyros on board. These have traditionally been the telescope’s biggest problem, and have been replaced twice over during shuttle missions. Three of today’s six however are using a new design which will hopefully extend their life significantly.

Hubble to search for Kuiper Belt targets for New Horizons

After completing a preliminary search for potential Kuiper Belt objects which the Pluto probe New Horizons might visit, scientists have decided to use the space telescope for a deeper more complete search.

As a first step, Hubble found two KBOs drifting against the starry background. They may or may not be the ideal target for New Horizons. Nevertheless, the observation is proof of concept that Hubble can go forward with an approved deeper KBO search, covering an area of sky roughly the angular size of the full Moon. The exceedingly challenging observation amounted to finding something no bigger than Manhattan Island, and charcoal black, located 4 billion miles away.

More here.

The astronomers who allocate time on the Hubble Space Telescope have decided to devote a large block for finding a Kuiper Belt object that the probe New Horizons might fly past.

The astronomers who allocate time on the Hubble Space Telescope have decided to devote a large block for finding a Kuiper Belt object that the probe New Horizons might fly past.

This allocation is still contingent upon a test observation to see if Hubble will be able to spot enough objects to make the long observations worthwhile.

Hubble spots an asteroid spout six comet-like tails.

Hubble spots an asteroid spout six comet-like tails.

Astronomers viewing our solar system’s asteroid belt with NASA’s Hubble Space Telescope have seen for the first time an asteroid with six comet-like tails of dust radiating from it like spokes on a wheel. Unlike all other known asteroids, which appear simply as tiny points of light, this asteroid, designated P/2013 P5, resembles a rotating lawn sprinkler. Astronomers are puzzled over the asteroid’s unusual appearance.

1 5 6 7 8