Tag: Hubble Space Telescope

Hubble operations contract extended to 2026, even as engineers work to fix it

3:10 pm

NASA announced today that it has extended the contract for operating the Hubble Space Telescope through 2026, even as it also provided an update on the effort of engineers to bring all the telescope’s science instruments out of safe mode.

[T]he agency has awarded a sole source contract extension to the Association of Universities for Research in Astronomy (AURA) in Washington for continued Hubble science operations support at the Space Telescope Science Institute (STScI) in Baltimore, which AURA operates for NASA. The award extends Hubble’s science mission through June 30, 2026, and increases the value of the existing contract by about $215 million (for a total of about $2.4 billion).

…Currently, the spacecraft team at NASA’s Goddard Space Flight Center in Greenbelt, Maryland, is investigating an issue involving missed synchronization messages that caused Hubble to suspend science observations Oct. 25. One of the instruments, the Advanced Camera for Surveys, resumed science observations Nov. 7, and continues to function as expected. All other instruments remain in safe mode.

During the week of Nov. 8, the Hubble team identified near-term changes that could be made to how the instruments monitor and respond to missed synchronization messages, as well as to how the payload computer monitors the instruments. This would allow science operations to continue even if several missed messages occur. The team has also continued analyzing the instrument flight software to verify that all possible solutions would be safe for the instruments.

In the next week, the team will begin to determine the order to recover the remaining instruments. The team expects it will take several weeks to complete the changes for the first instrument.

It appears that it is going to take some time to bring all the instruments back in line, considering that they are fixing the instruments one-by-one, in sequence, and that the first fix is taking weeks. Hopefully as they get each instrument back they will be able to move faster once they know what works.

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Hubble camera back in operation

2:16 pm

Good news! As engineers work to fix the problem that caused the Hubble Space Telescope to shut down on October 25th, they have now successfully returned Hubble’s most important camera back to doing science.

The Hubble team successfully recovered the Advanced Camera for Surveys instrument Nov. 7. The instrument has started taking science observations once again. Hubble’s other instruments remain in safe mode while NASA continues investigating the lost synchronization messages first detected Oct. 23. The camera was selected as the first instrument to recover as it faces the fewest complications should a lost message occur.

This success strongly suggests they have pinpointed the software issue that caused the shutdown, and can now step-by-step reactivate all the other instruments in the coming week.

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Hubble still in safe mode

9:05 am

NASA released a new but relatively terse update on November 1st describing the status of the Hubble Space Telescope, which has been in safe mode since October 25th.

Hubble’s science instruments issued error codes at 1:46 a.m. EDT Oct. 23, indicating the loss of a specific synchronization message. This message provides timing information the instruments use to correctly respond to data requests and commands. The mission team reset the instruments, resuming science operations the following morning.

At 2:38 a.m. EDT, Oct. 25, the science instruments again issued error codes indicating multiple losses of synchronization messages. As a result, the science instruments autonomously entered safe mode states as programmed.

Mission team members are evaluating spacecraft data and system diagrams to better understand the synchronization issue and how to address it. They also are developing and testing procedures to collect additional data from the spacecraft. These activities are expected to take at least one week.

In other words, the engineers presently do not understand the problem, and are working at pinpointing its cause.

This is not a “glitch”. If used properly that word really refers to something that is akin to a short burp in operations. Hubble has been shut down now for ten days, and will remain so for at least one more week. This is a serious problem that remains unsolved.

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Hubble in safe mode again

10:50 pm

According to NASA’s Twitter feed for the Hubble Space Telescope, it went into safe mode earlier this week because of “issues with internal communications.”

Hubble’s science instruments went into safe mode on Monday after experiencing synchronization issues with internal spacecraft communications. Science observations have been temporarily suspended while the team investigates the issue. The instruments remain in good health.

Much of the press is using that lovely buzzword of bureaucrats, calling this a “glitch.” The goal of that word is to make the problem seem minor and no big deal.

It can’t be minor and no big deal however if the telescope shut down six days ago and remains out of service. This is not a “glitch.” This is a serious issue that is taking time to resolve.

Furthermore, I get more concerned when no further information is provided. As far as I can so far find, the quote above is the only information NASA has released. And that information is remarkably vague and uninformative.

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Water and carbon monoxide detected in exoplanet’s atmosphere

9:54 am

Astronomers, using both the Hubble Space Telescope and the ground-based Gemini Telescope, have detected water and carbon monoxide in the atmosphere of an exoplanet 320 light years away.

Previously hydrogen, helium, hydrogen cyanide, iron, and magnesium have been detected in the atmospheres of a variety of exoplanets. In other cases scientists found exoplanets that were devoid of water.

This detection of water and carbon monoxide is a first for these two materials, and is somewhat significant as it is the first detection that suggests an exoplanet atmosphere that might have similarities to Earth.

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Hubble data detects persistent water vapor on one of Europa’s hemispheres

1:30 pm

Using data from the Hubble Space Telescope spanning sixteen Earth years, scientists have detected the presence of water vapor on Europa, but strangely spread only across one of the moon’s hemispheres.

Previous observations of water vapor on Europa have been associated with plumes erupting through the ice, as photographed by Hubble in 2013. They are analogous to geysers on Earth, but extend more than 60 miles high. They produce transient blobs of water vapor in the moon’s atmosphere, which is only one-billionth the surface pressure of Earth’s atmosphere.

The new results, however, show similar amounts of water vapor spread over a larger area of Europa in Hubble observations spanning from 1999 to 2015. This suggests a long-term presence of a water vapor atmosphere only in Europa’s trailing hemisphere – that portion of the moon that is always opposite its direction of motion along its orbit. The cause of this asymmetry between the leading and trailing hemisphere is not fully understood.

First, it must be emphasized that the amounts of atmospheric water being discussed are tiny, so tiny that on Earth we might consider this a vacuum.

Second, that the water vapor is only seen on the trailing hemisphere suggests there is some sort of orbital influence involved, though what that influence is remains unknown.

Hopefully when Europa Clipper finally arrives in orbit around Jupiter in 2030, with a path that will fly past Europa fifty times, we will some clarity on these questions.

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Data suggests the winds in Jupiter’s Great Red Spot are changing

2:46 pm

Changing wind speeds in Great Red Spot
Click for original image.

Data accumulated from 2009 to 2020 by the Hubble Space Telescope suggest that the outer winds in Jupiter’s Great Red Spot have speeded up by about 8%, while the winds in the spot’s inner regions have slowed.

The change in wind speeds they have measured with Hubble amount to less than 1.6 miles per hour per Earth year. “We’re talking about such a small change that if you didn’t have eleven years of Hubble data, we wouldn’t know it happened,” said Simon. “With Hubble we have the precision we need to spot a trend.” Hubble’s ongoing monitoring allows researchers to revisit and analyze its data very precisely as they keep adding to it. The smallest features Hubble can reveal in the storm are a mere 105 miles across, about twice the length of the state of Rhode Island.

“We find that the average wind speed in the Great Red Spot has been slightly increasing over the past decade,” Wong added. “We have one example where our analysis of the two-dimensional wind map found abrupt changes in 2017 when there was a major convective storm nearby.”

The graphic above shows the different wind speeds between the spot’s inner and outer regions, not the increase in speed described in this press release.

To put it mildly, these results are uncertain. We simply could be seeing the long term random fluctuations in the storm, or the change could simply be a reflection of the data’s margin of error. Moreover, since the data covers only the top layer of the Great Red Spot, it tells us nothing about the storm’s deeper regions or its more fundamental origins.

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Galaxies in the early universe don’t fit the theories

9:33 am

The uncertainty of science: New data from both the ALMA telescope in Chile and the Hubble Space Telescope about six massive galaxies in the early universe suggest that there are problems and gaps in the presently accepted theories about the universe’s formation.

Early massive galaxies—those that formed in the three billion years following the Big Bang should have contained large amounts of cold hydrogen gas, the fuel required to make stars. But scientists observing the early Universe with the Atacama Large Millimeter/submillimeter Array (ALMA) and the Hubble Space Telescope have spotted something strange: half a dozen early massive galaxies that ran out of fuel. The results of the research are published today in Nature.

Known as “quenched” galaxies—or galaxies that have shut down star formation—the six galaxies selected for observation from the REsolving QUIEscent Magnified galaxies at high redshift. or the REQUIEM survey, are inconsistent with what astronomers expect of the early Universe.

It was expected that the early universe would have lots of that cold hydrogen for making stars. For some galaxies to lack that gas is inexplicable, and raises questions about the assumptions inherent in the theory of the Big Bang. It doesn’t disprove it, it simply makes it harder to fit the facts to the theory, suggesting — as is always the case — that the reality is far more complicated than the theories of scientists.

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Astronomers discover white dwarf stars still burning hydrogen

9:50 am

The uncertainty of science: Using Hubble observations of the white dwarfs in two different globular clusters, astronomers have discovered that — contrary to the consensus opinion — some white dwarf stars are not slowly cooling embers of a dead star, but are still generating nuclear fusion by burning hydrogen in their outer layers.

Using Hubble’s Wide Field Camera 3 the team observed [globular clusters] M3 and M13 at near-ultraviolet wavelengths, allowing them to compare more than 700 white dwarfs in the two clusters. They found that M3 contains standard white dwarfs, which are simply cooling stellar cores. M13, on the other hand, contains two populations of white dwarfs: standard white dwarfs and those which have managed to hold on to an outer envelope of hydrogen, allowing them to burn for longer and hence cool more slowly.

Comparing their results with computer simulations of stellar evolution in M13, the researchers were able to show that roughly 70% of the white dwarfs in M13 are burning hydrogen on their surfaces, slowing down the rate at which they are cooling.

This discovery could have consequences for how astronomers measure the ages of stars in the Milky Way galaxy. The evolution of white dwarfs has previously been modeled as a predictable cooling process. This relatively straightforward relationship between age and temperature has led astronomers to use the white dwarf cooling rate as a natural clock to determine the ages of star clusters, particularly globular and open clusters. However, white dwarfs burning hydrogen could cause these age estimates to be inaccurate by as much as 1 billion years.

In other words, many past age estimates for star clusters could be very wrong, which in turn could mean the general understanding of the evolution of these objects could be very wrong as well.

These results also illustrate a fact that astronomers seem to always forget. The stars in any one category (white dwarfs, red super giants, yellow stars like the Sun, etc.) are not all identical, and thus their life and death processes will not all follow the predicted stages, like clockwork. Things are always far more complicated. Though the predictions might be broadly right, there will be many variations, so many that it will often be difficult to draw a generalized conclusion.

It seems that with white dwarfs astronomers have made this mistake, and now must rethink many of their conclusions.

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1st water vapor in Ganymede’s atmosphere, detected using data from Hubble

9:06 am

Using Hubble data, astronomers have detected the first evidence of water vapor in the atmosphere of Jupiter’s largest moon, Ganymede.

Though larger than the blistering planet Mercury, the Jovian moon Ganymede is no place to go sunbathing. Located ½-billion miles from the Sun, the water ice on its surface is frozen solid in frigid temperatures as low as minus 300 degrees Fahrenheit. This makes the ice as hard as rock. Still, a rain of charged particles from the Sun is enough to turn the ice into water vapor at high noon on Ganymede.

This is the first time such evidence has been found, courtesy of the Hubble Space Telescope’s spectroscopic observations of aurora on Ganymede spanning two decades. The auroras are used to trace the presence of oxygen, which then is linked to the presence of water molecules sputtering off the surface. Ganymede has a deep ocean located an estimated 100 miles below the surface. That’s too deep for water vapor to be leaking out.

This detection has a margin of uncertainty, but it provides a baseline for the up close observations planned for Europe’s JUICE orbiter, set to launch in ’22 and arrive in Jupiter orbit in ’29. JUICE’s study focus will be the three Galilean moons that appear to have lots of ice, Ganymede, Calisto, and Europa.

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Hubble returned to science operations

8:49 am

Engineers today completed their testing of their computer hardware fix on the Hubble Space Telescope and took it out of safe mode, allowing science observations to resume after more than a month.

The first observation is scheduled for Saturday afternoon after some instrument calibrations are completed. Most observations missed while science operations were suspended will be rescheduled for a later date.

Now let us all pray that there are no more major failures for the next few years until the U.S. capabilities in space grow and a relatively fast mission to repair the telescope is possible.

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Engineers report Hubble fix appears successfully

8:50 am

Engineers this morning announced that their attempt to switch to backup computer hardware on the Hubble Space Telescope was successful.

The switch included bringing online the backup Power Control Unit (PCU) and the backup Command Unit/Science Data Formatter (CU/SDF) on the other side of the Science Instrument and Command & Data Handling (SI C&DH) unit. The PCU distributes power to the SI C&DH components, and the CU/SDF sends and formats commands and data. In addition, other pieces of hardware onboard Hubble were switched to their alternate interfaces to connect to this backup side of the SI C&DH. Once these steps were completed, the backup payload computer on this same unit was turned on and loaded with flight software and brought up to normal operations mode.

They are now doing tests to make sure everything is working as expected, and preparing the telescope to bring it out of safe mode and resume science operations.

This is great news, but to bring everyone down to Earth, we must remember that Hubble no longer has any redundancy in this area. Should there be another similar computer failure, the telescope will then be dead in the water, with the only way to bring it back a manned or robotic mission — something we presently do not have the capacity to do — to replace these units.

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Hubble update: Engineers pinpoint issue, prepare to fix it

12:38 pm

In an update today on the status for bringing the Hubble Space Telescope back into science operations, the engineers say they think they have pinpointed the failed unit, and are ready to do the switch to a backup.

A series of multi-day tests, which included attempts to restart and reconfigure the computer and the backup computer, were not successful, but the information gathered from those activities has led the Hubble team to determine that the possible cause of the problem is in the Power Control Unit (PCU).

The PCU also resides on the SI C&DH unit. It ensures a steady voltage supply to the payload computer’s hardware. The PCU contains a power regulator that provides a constant five volts of electricity to the payload computer and its memory. A secondary protection circuit senses the voltage levels leaving the power regulator. If the voltage falls below or exceeds allowable levels, this secondary circuit tells the payload computer that it should cease operations. The team’s analysis suggests that either the voltage level from the regulator is outside of acceptable levels (thereby tripping the secondary protection circuit), or the secondary protection circuit has degraded over time and is stuck in this inhibit state.

Because no ground commands were able to reset the PCU, the Hubble team will be switching over to the backup side of the SI C&DH unit that contains the backup PCU. All testing of procedures for the switch and associated reviews have been completed, and NASA management has given approval to proceed. The switch will begin Thursday, July 15, and, if successful, it will take several days to completely return the observatory to normal science operations.

Engineers did a similar switch in 2008, so they are very confident it will work this time also. However, once done, the telescope will no longer have backups for any of these computer modules. The next failure in any of them will shut the telescope down, for good.

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Engineers successful complete simulation of Hubble repair

12:30 pm

Though the details released are sparse, engineers working to get the Hubble Space Telescope back in operation since it shut down due to a computer problem in mid-June report today that they have successfully completed a simulation of the procedures they need to do to fix the problem.

This is their entire report:

[The engineers] successfully completed a test of procedures that would be used to switch to backup hardware on Hubble in response to the payload computer problem. This switch could occur next week after further preparations and reviews.

Apparently, because the switch to backup hardware requires switching more than one unit, the sequence is important and following it correctly is critical. It appears they have now determined the correct sequence and will attempt it on Hubble next week.

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Hubble update: Engineers narrow possible failed hardware to one of two units

5:09 pm

Engineers working to pinpoint the cause of the computer hardware issue that has placed the Hubble Space Telescope in safe mode since June 13th have now narrowed the possible failed hardware to one of two units.

The source of the computer problem lies in the Science Instrument Command and Data Handling (SI C&DH) unit, where the payload computer resides. A few hardware pieces on the SI C&DH could be the culprit(s).

The team is currently scrutinizing the Command Unit/Science Data Formatter (CU/SDF), which sends and formats commands and data. They are also looking at a power regulator within the Power Control Unit, which is designed to ensure a steady voltage supply to the payload computer’s hardware. If one of these systems is determined to be the likely cause, the team must complete a more complicated operations procedure to switch to the backup units. This procedure would be more complex and riskier than those the team executed last week, which involved switching to the backup payload computer hardware and memory modules. To switch to the backup CU/SDF or power regulator, several other hardware boxes on the spacecraft must also be switched due to the way they are connected to the SI C&DH unit.

Over the next week or so, the team will review and update all of the operations procedures, commands and other related items necessary to perform the switch to backup hardware. They will then test their execution against a high-fidelity simulator.

The team performed a similar switch in 2008, which allowed Hubble to continue normal science operations after a CU/SDF module failed.

That such a switch was done successfully in the past is a very hopeful sign. However, it sounds as though they are not 100% sure they have pinpointed the actual issue, which means that this switch still might not fix the problem.

We can only wait and hope. And even if the fix works, Hubble will no longer have working backup units for these pieces of hardware. Should any of the backup that are now being activated fail, the telescope will fail, and this time it won’t be fixable with the equipment on board.

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Hubble update: Still no solution

2:02 pm

An update today from the engineers trouble-shooting the problem on the Hubble Space Telescope that put it into safe mode on June 13 continue to show the problem is complex, and has not yet been traced to its source.

Additional tests performed on June 23 and 24 included turning on the backup computer for the first time in space. The tests showed that numerous combinations of [a number of] hardware pieces from both the primary and backup payload computer all experienced the same error – commands to write into or read from memory were not successful.

Since it is highly unlikely that all individual hardware elements have a problem, the team is now looking at other hardware as the possible culprit, including the Command Unit/Science Data Formatter (CU/SDF), another module on the SI C&DH [the module that holds the telescope’s computers]. The CU formats and sends commands and data to specific destinations, including the science instruments. The SDF formats the science data from the science instruments for transmission to the ground. The team is also looking at the power regulator to see if possibly the voltages being supplied to hardware are not what they should be. A power regulator ensures a steady constant voltage supply. If the voltage is out of limits, it could cause the problems observed.

They remain hopeful they can find the problem and fix it, though the longer it takes the more worrisome it becomes.

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Update on attempts to bring Hubble back to life

4:26 pm

Engineers have released an update on their attempts to bring Hubble out of safe mode that are indicating that they are honing in on the cause of the problem.

After performing tests on several of the computer’s memory modules, the results indicate that a different piece of computer hardware may have caused the problem, with the memory errors being only a symptom. The operations team is investigating whether the Standard Interface (STINT) hardware, which bridges communications between the computer’s Central Processing Module (CPM) and other components, or the CPM itself is responsible for the issue. The team is currently designing tests that will be run in the next few days to attempt to further isolate the problem and identify a potential solution.

This step is important for determining what hardware is still working properly for future reference. If the problem with the payload computer can’t be fixed, the operations team will be prepared to switch to the STINT and CPM hardware onboard the backup payload computer. The team has conducted ground tests and operations procedure reviews to verify all the commanding required to perform that switch on the spacecraft.

It appears that no matter what solution they arrive at, they will still require several days to test the solution to make sure it works. This update however is very hopeful, as it does appear they are locating the cause and have avenues for fixing it.

Hubble went into safe mode on June 13, which means it has now been out of operation for more than ten days.

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Hubble remains out of commission, with no repair date in sight

9:32 am

According to a statement to Space.com provided by the engineers trying to fix the Hubble Space Telescope, “there is no definitive timeline for bringing the computer back online.”

The Hubble operations team is working to solve the payload computer issue onboard the Hubble Space Telescope. The team is working to collect all the data available to them to isolate the problem and determine the best path forward for bringing the computer back to operations. At this time, there is no definitive timeline for bringing the computer back online. However, the team has multiple options available to them and are working to find the best solution to return the telescope to science operations as soon as possible.

…Assuming that this problem is corrected via one of the many options available to the operations team, Hubble is expected to continue yielding amazing discoveries into the late 2020s or beyond,” the operations team at NASA’s Goddard Space Flight Center in Maryland told Space.com in an email. However, “there is no definitive timeline yet as to when this will be completed, tested and brought back to operational status,

I gather from this that they do have options to might fix the problem, but they have also found the problem to be more complex than expected.

While I honestly am confident these engineers can bring the telescope back to life, we must all be prepared for the strong possibility that this might be the moment when such a repair is impossible. If so, our vision of the heavens will once again be blinded by the poor vision available to us from inside the Earth’s atmosphere. And that vision will not be cleared in the foreseeable future by an American or western optical space telescope, as none are being designed, no less built.

The Chinese however are building one, for their purposes, which will be better than Hubble and is set to launch within the next few years to fly in formation with their new space station, close by so that astronauts can do repairs if necessary.

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First attempts to fix Hubble fail

9:43 am

An attempt to switch the Hubble Space Telescope to a different backup computer module in order to bypass a broken unit failed last week, leaving the telescope in safe mode.

A payload computer on Hubble stopped working June 13, the agency said in a June 16 statement. Engineers speculated that the computer, used to manage operations of Hubble’s science instruments, malfunctioned because of a degrading memory module, putting the instruments into a safe mode.

The agency said at the time that it would switch of a backup memory module that day and, after about a day of testing, restart the instruments and resume science observations.

However, in a June 18 statement, NASA said those efforts to switch to a backup memory module failed because “the command to initiate the backup module failed to complete.” An attempt to restore the computer with both the original memory module and the backup unit also failed.

While the engineers at the Space Telescope Science Institute, that operates Hubble, have expressed confidence they can overcome these issues, the failures this week are truly troublesome. We may truly be facing the end of the telescope,

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Hubble in safe mode due to computer problem

1:47 pm

A computer failure on June 13th put the Hubble Space Telescope in safe mode, with engineers hoping to have the problem resolved and the telescope back in operation by tomorrow.

NASA is working to resolve an issue with the payload computer on the Hubble Space Telescope. The computer halted on Sunday, June 13, shortly after 4 p.m. EDT. After analyzing the data, the Hubble operations team is investigating whether a degrading memory module led to the computer halt. The team is preparing to switch to one of several backup modules on Wednesday, June 16. The computer will then be allowed to run for approximately one day to verify that the problem has been solved. The team would then restart all science instruments and return the telescope to normal science operations.

The unit itself, while built in the 1980s, was only launched to Hubble in 2009 as part of the last shuttle repair mission.

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A lopsided spiral galaxy

12:54 pm

Losided spiral galaxy
Click for full image.

For a change, today’s cool image is not from Mars, but instead goes deep into space. The photo to the right, reduced to post here, was taken by the Hubble Space Telescope of the relatively nearby spiral galaxy NGC 2276, located about 120 million light years away. As the caption explains:

The magnificent spiral galaxy NGC 2276 looks a bit lopsided in this Hubble Space Telescope snapshot. A bright hub of older yellowish stars normally lies directly in the center of most spiral galaxies. But the bulge in NGC 2276 looks offset to the upper left.

In reality, a neighboring galaxy to the right of NGC 2276 (NGC 2300, not seen here) is gravitationally tugging on its disk of blue stars, pulling the stars on one side of the galaxy outward to distort the galaxy’s normal fried-egg appearance. This sort of “tug-of-war” between galaxies that pass close enough to feel each other’s gravitational pull is not uncommon in the universe. But, like snowflakes, no two close encounters look exactly alike.

The scientists also note that the bright edge along the galaxy’s north and west perimeter mark regions of intense star-formation. In those same regions astronomers six years ago identified the first medium-sized black hole ever found.

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The changing seasons of Saturn

1:58 pm

Saturn changing
Click for full image.

Images of Saturn taken by the Hubble Space Telescope since 2018 now reveal the slow seasonal changes to the gas giant’s atmosphere during its lengthy year, twenty-nine Earth years long.

The Hubble data show that from 2018 to 2020 the equator got 5 to 10 percent brighter, and the winds changed slightly. In 2018, winds measured near the equator were about 1,000 miles per hour (roughly 1,600 kilometers per hour), higher than those measured by NASA’s Cassini spacecraft during 2004-2009, when they were about 800 miles per hour (roughly 1,300 kilometers per hour). In 2019 and 2020 they decreased back to the Cassini speeds. Saturn’s winds also vary with altitude, so the change in measured speeds could possibly mean the clouds in 2018 were around 37 miles (about 60 kilometers) deeper than those measured during the Cassini mission. Further observations are needed to tell which is happening.

The photo above shows Saturn’s northern hemisphere in 2018, 2019, and 2020. Note how the darker region at the pole grows with time.

This data supplements the data obtained by Cassini when it was in orbit around Saturn, and is presently the best information we can get since the Cassini mission ended.

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Hubble’s wide field camera returns to operation

1:39 pm

Though the Hubble Space Telescope returned to science operations on March 12th after going into safe mode, its wide field camera did not.

Engineers however now report that they have successfully restored the camera to operations as well. The reason for the delayed restoration exemplifies Hubble’s aging status.

Analysis showed that voltage levels in WFC3 power supplies have slowly decreased over time as their electronics aged. The electronics experience colder temperatures when the hardware is turned off in safe mode. This factor coupled with the power the instrument components draw as they are turned back on contributed to the small voltage fluctuation that suspended WFC3 recovery operations. Further detailed analysis indicated that it would be safe to slightly reduce the low voltage limit to avoid a future suspend, and it would be safe to recover the instrument to its science state.

The instrument has now been safely recovered. Standard calibration of the instrument and other pre-observation activities will be conducted this week.

All the telescope’s equipment has been adjusted in recent years to deal with the varying ages of its instruments and its main structure. For example, this wide field camera was installed during the last shuttle serving mission in 2009, and is therefore one of Hubble’s newest components. It however is now more than a decade old, and thus needs careful handling to function properly.

Other components are far older, such as the primary motor to open and close the telescope’s “lens cap”. That failed during this safe mode, forcing engineers to switch to a back up motor to control the cap. Whether they can recover that primary motor is presently unclear, though unlikely.

Expect more such issues in the coming years.

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Hubble about to resume science operations even with new issues

9:14 am

Engineers have fixed the computer software issue that caused the Hubble Space Telescope to go into safe mode this week, and are preparing it to return to full science operations.

It appears the problem was caused by a software upgrade that caused a conflict.

More serious however was this problem, which could have damaged the telescope beyond repair had it had been randomly pointed at the Sun during safe mode.

In entering safe mode on Sunday, however, the team discovered that the aperture door located at the top of the telescope failed to automatically close. This door is a safeguard designed to keep the Sun’s damaging light and heat out of the telescope’s interior, protecting its sensitive instruments and their surroundings. It serves as a safety net if Hubble accidently points in the direction of the Sun due to an error or hardware problem.

…The team has looked at spacecraft engineering data, run various tests, and verified that the door did indeed remain open despite the commands and power being sent to close it. Additional attempts to move the door by sending commands from the ground to its primary motor also failed to make the door move. However, the same commands sent from the ground to its backup motor did indicate movement, and that motor is now set as the primary motor. The team is looking at options to further reduce any associated risk.

It appears the primary motor that moves the door has failed. Fortunately there is a backup motor, but this is just one more item where the telescope has lost redundancy. We are very lucky that during safe mode the telescope didn’t end up pointing at the Sun, even for a very short time, for that would have ended Hubble’s operation for good. I suspect the safe mode software includes protections against that occurrence, but the possibility nonetheless existed.

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Hubble goes into safe mode

3:19 pm

Due to a software issue, the Hubble Space Telescope shifted into safe mode early yesterday and stopped doing its programmed science observations.

The engineers seem confident all will eventually be well, but we must also remember the telescope’s infrastructure (not its instruments) was built in the early 1980s and has been in space since 1990. That makes many parts of this telescope 40 years old. We are increasingly faced with the possibility of a fatal fault occurring that shuts it down for good, with no way at the present time to reach it and fix it, and with the only comparable optical space telescope in the works one being built by China to fly in formation with its space station.

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Colliding galaxies!

2:19 pm

Colliding galaxies!
Click here and here to see full images.

Cool images from Hubble! The two photos to the right, cropped and reduced to post here, shows two different galaxies undergoing a collision with another galaxy. Both images are from of a montage of six galaxy merger images from the Hubble Space Telescope, released yesterday.

To celebrate a new year, the NASA/ESA Hubble Space Telescope has published a montage of six beautiful galaxy mergers. Each of these merging systems was studied as part of the recent HiPEEC survey to investigate the rate of new star formation within such systems. These interactions are a key aspect of galaxy evolution and are among the most spectacular events in the lifetime of a galaxy.

It is during rare merging events that galaxies undergo dramatic changes in their appearance and in their stellar content. These systems are excellent laboratories to trace the formation of star clusters under extreme physical conditions.

The first galaxy merger to the right is dubbed NGC 6052, and is located in the constellation of Hercules about 230 million light-years away. This pair of colliding galaxies, according to the caption, “were first discovered in 1784 by William Herschel and were originally classified as a single irregular galaxy because of their odd shape. However, we now know that NGC 6052 actually consists of two galaxies that are in the process of colliding.”

The second image shows two galaxies, IC 694 and NGC 3690, about 700 millions after they had completed a close pass of each other. From the caption: “As a result of this interaction, the system underwent a fierce burst of star formation. In the last fifteen years or so six supernovae have popped off in the outer reaches of the galaxy, making this system a distinguished supernova factory.”

You can see all six merger images here, though to my eye these two are the most impressive.

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Dark storm on Neptune changes direction unexpectedly

8:35 am

Dark storm on Neptune
Click for full image.

Using the Hubble Space Telescope, astronomers have found that a dark storm discovered on Neptune in 2018 has been drifting across the gas giant in unexpected ways.

The storm, which is wider than the Atlantic Ocean, was born in the planet’s northern hemisphere and discovered by Hubble in 2018. Observations a year later showed that it began drifting southward toward the equator, where such storms are expected to vanish from sight. To the surprise of observers, Hubble spotted the vortex change direction by August 2020, doubling back to the north. Though Hubble has tracked similar dark spots over the past 30 years, this unpredictable atmospheric behavior is something new to see.

Equally as puzzling, the storm was not alone. Hubble spotted another, smaller dark spot in January this year that temporarily appeared near its larger cousin. It might possibly have been a piece of the giant vortex that broke off, drifted away, and then disappeared in subsequent observations.

The photo to the right, cropped and reduced to post here, shows both storms. The smaller dark spot can be seen faintly to the right of the larger storm.

Since Hubble has been observing Neptune in 1993 it has seen four such storms, all of which have faded away after about two Earth years. What causes the storms as well as their motions in Neptune’s atmosphere remains unknown, and any theories posited (such as those noted at the link) are highly unreliable, considering the paucity of data we have about Neptune’s atmosphere and the meteorology of such gas giants.

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Hubble captures 20-year fading of planetary nebula

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The fading of the Stingray Nebula
Click for full image.

Astronomers using the Hubble Space Telescope have now tracked the spectacular fading of the Stingray Nebula, which when it was discovered in the mid-1990s was labeled the youngest such object ever found.

Astronomers have caught a rare look at a rapidly fading shroud of gas around an aging star. Archival data from NASA’s Hubble Space Telescope reveal that the nebula Hen 3-1357, nicknamed the Stingray nebula, has faded precipitously over just the past two decades. Witnessing such a swift rate of change in a planetary nebula is exceeding rare, say researchers.

Images captured by Hubble in 2016, when compared to Hubble images taken in 1996, show a nebula that has drastically dimmed in brightness and changed shape. Bright blue fluorescent tendrils and filaments of gas toward the center of the nebula have all but disappeared, and the wavy edges that earned this nebula its aquatic-themed name are virtually gone. The young nebula no longer pops against the black velvet background of the vast universe.

Astronomers have found that the central star had been heating precipitiously in the late 20th century, from 40K to 108K degrees Fahrenheit. Since then it has begun to cool. They think that flash of heat, caused by what they think was short period of helium fusion, caused the planetary nebula to brighten, and now fade.

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Hubble sees too much infrared energy from gamma ray burst

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The uncertainty of science: During a short gamma ray burst (GRB) that was observed in a distant galaxy on May, astronomers were baffled when measurements from the Hubble Space Telescope detected ten times more near infrared energy that they predict from this type of GRB.

GRBs fall into two classes. First there are the long bursts, which are thought to form from the collapse of a massive star into a black hole, resulting in a powerful supernova and GRB. Second there are the short bursts, which scientists think occur when two neutron stars merge.

The problem with this GRB is that though it was short and somewhat similar to other short GRBs across most wavelengths, in the near infrared Hubble detected far too much energy.

“These observations do not fit traditional explanations for short gamma-ray bursts,” said study leader Wen-fai Fong of Northwestern University in Evanston, Illinois.

…Fong and her team have discussed several possibilities to explain the unusual brightness that Hubble saw. While most short gamma-ray bursts probably result in a black hole, the two neutron stars that merged in this case may have combined to form a magnetar, a supermassive neutron star with a very powerful magnetic field. “You basically have these magnetic field lines that are anchored to the star that are whipping around at about a thousand times a second, and this produces a magnetized wind,” explained Laskar. “These spinning field lines extract the rotational energy of the neutron star formed in the merger, and deposit that energy into the ejecta from the blast, causing the material to glow even brighter.”

What is intriguing about their theory is that this merger of two neutron stars simply resulted in a larger neutron star, not a black hole. This new neutron star was also a magnetar and pulsar, but unlike a black hole, it was a still-visible physical object. And yet its creation in this GRB produced more energy.

When GRBs were first discovered, I was always puzzled why so many astronomers seemed to insist there must be a single explanation for them. With time, when two classes of GRBs were discovered, this assumption was then replaced with the equally puzzling insistence that only two types of events explained them.

It seemed to me that that such explosions had too many potential variables, and could easily have a wide range of causes, though all related to the destruction or merger of massive stars. As the data continues to accumulate this now appears increasingly the case.

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Hubble creates time lapse movie of fading supernova

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Using the Hubble Space Telescope, astronomers have created a time lapse movie showing the fading of a supernova in a nearby galaxy over a year.

The supernova is captured by Hubble in exquisite detail within this galaxy in the left portion of the image. It appears as a very bright star located on the outer edge of one of its beautiful swirling spiral arms. This new and unique time-lapse of Hubble images created by the ESA/Hubble team shows the once bright supernova initially outshining the brightest stars in the galaxy, before fading into obscurity during the year of observations. This time-lapse consists of observations taken over the course of one year, from February 2018 to February 2019.

The video of that time lapse is embedded below the fold.

The galaxy itself is located 70 million light years away. That the supernova of this single star initially outshone the entire galaxy indicates the almost unimaginable power of the explosion.
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