Tag: science

Dawn recovers from safe mode

9:17 am

Spot 1

Beginning on June 30 Dawn experienced an as yet unexplained “anomaly” that put it into safe mode for several days.

According to JPL, engineers have uploaded “configuration changes” that solved the problem, and the spacecraft has returned to normal operations, continuing its second mapping orbit of Ceres. From this position they are gathering wide angle images of the entire planet, from which they will construct a detailed global map to be used as a baseline during later more detailed close-up orbits. For example, they released this very nice image today of what is called “Spot 1”, shown on the right. I have cropped it to focus on the spot itself. Looks almost like scattered snow on the surface, doesn’t it?

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Obamacare continues to cause health insurance premiums to skyrocket

1:06 pm

Finding out what’s in it: Health insurance companies are now requesting (and getting) rate increases from 23 to 54 percent due to the increased costs imposed by Obamacare.

Blue Cross and Blue Shield plans — market leaders in many states — are seeking rate increases that average 23 percent in Illinois, 25 percent in North Carolina, 31 percent in Oklahoma, 36 percent in Tennessee and 54 percent in Minnesota, according to documents posted online by the federal government and state insurance commissioners and interviews with insurance executives.

The Oregon insurance commissioner, Laura N. Cali, has just approved 2016 rate increases for companies that cover more than 220,000 people. Moda Health Plan, which has the largest enrollment in the state, received a 25 percent increase, and the second-largest plan, LifeWise, received a 33 percent increase.

At the same time, many insurance companies are merging or leaving the market because of the law makes profitability impossible.

Obviously, we must all then vote for Democrats so they can use their brilliance (demostrated so clearly with Obamacare) to solve this problem by nationalizing healthcare.

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New Horizons temporarily loses contact with Earth

9:38 am

Engineers lost contact with New Horizons for an hour and twenty-one minutes on Saturday.

Engineers have since begun talking with the probe again, but NASA says it will take up to several days to get New Horizons back to normal. In the meantime, the US$700-million spacecraft is not recording science data. It is just 11 million kilometres from Pluto, and closing in fast.

Communication issues are exacerbated by the fact that it takes four and a half hours to send a signal, traveling at light speed, across the nearly 4.8 billion kilometres to the spacecraft — and four and a half hours back. In that elapsed time, the Earth has rotated so much that mission controllers must switch from one to another of the three deep-space antennas that communicate with spacecraft: in Goldstone, California; Canberra; and Madrid.

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The jets on Comet 67P/C-G come from its sinkholes

10:18 am

More on the comet sinkholes! New data from Rosetta has now confirmed that some of the plumes or jets that the spacecraft has seen emanating from Comet 67P/C-G come directly from the sinkholes that they have discovered on the nucleus.

In a study reported today in the science journal Nature, 18 quasi-circular pits have been identified in the northern hemisphere of the comet, some of which are the source of continuing activity. The pits are a few tens to a few hundreds of metres in diameter and extend up to 210 m below the surface to a smooth dust-covered floor. Material is seen to be streaming from the most active pits. “We see jets arising from the fractured areas of the walls inside the pits. These fractures mean that volatiles trapped under the surface can be warmed more easily and subsequently escape into space,” says Jean-Baptiste Vincent from the Max Planck Institute for Solar System Research, lead author of the study.

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TMT protesters complain about road closure

9:59 am

The leader of the protest that is opposing the construction of the Thirty Meter Telescope (TMT) is now complaining about the road closure imposed by Hawaii’s government that is preventing him and his followers from returning to the mountain.

“The telescope employees have been able to access the mountain every single day to go up and come back down and even we as protectors of the mountain have been given daily access to conduct pule and religious practices on the mountain,” said Kahookahi Kanuha, a member of Ku Kia’i Mauna, which hopes to keep the telescope from being built. “So, if they do deem it unsafe, it is quite irresponsible of them to allow other individuals up the mountain.”

So let me get this straight: He thinks it is wrong for the people who own or lease the mountain — who have legal right to control access — to block the protesters, but he sees nothing wrong with him going there — trespassing — and blocking access to others. What a hypocrite.

This article proves that my analysis from Tuesday is correct. The government has shut the road mainly to quietly get the protesters out of the way and let things cool down. When construction resumes, I guarantee that road access will restricted to prevent the protesters from returning and blocking the road. (Update: The quotes here from the state’s attorney general provide even further confirmation that the state will not allow protests to obstruct future access to construction crews.)

One other note: The author of the first article above uses the typical dishonest mainstream media technique of only quoting one protester, the activist leader, while claiming that “protesters” are objecting. The data in the article, however, does not document this spin. As far as I can tell, the only one complaining about the road closure is this one guy.

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What we will and will not see during the Pluto fly-by

9:32 am

Pluto's two hemispheres

The images above, released today by the New Horizons’ science team, provide the best global view so far of Pluto’s two hemispheres. I have cropped and rearranged the original to focus on Pluto.

The images illustrate some basic new knowledge about the planet. For one, scientists have now identified the planet’s poles, based upon its rotation. While scientists had had a very rough vague idea of Pluto’s rotation and inclination beforehand, they have now pinned it down pretty precisely.

The images also show the planet’s most striking and unique features, though not with enough resolution to tell us what they are.

New color images from NASA’s New Horizons spacecraft show two very different faces of the mysterious dwarf planet, one with a series of intriguing spots along the equator that are evenly spaced. Each of the spots is about 300 miles in diameter, with a surface area that’s roughly the size of the state of Missouri.

Scientists have yet to see anything quite like the dark spots; their presence has piqued the interest of the New Horizons science team, due to the remarkable consistency in their spacing and size. While the origin of the spots is a mystery for now, the answer may be revealed as the spacecraft continues its approach to the mysterious dwarf planet. “It’s a real puzzle—we don’t know what the spots are, and we can’t wait to find out,” said New Horizons principal investigator Alan Stern of the Southwest Research Institute, Boulder. “Also puzzling is the longstanding and dramatic difference in the colors and appearance of Pluto compared to its darker and grayer moon Charon.”

This image release also shows us what we will and will not see during the fly-by. The image on the left is the “encounter hemisphere.” This is the hemisphere that will be in view during New Horizons’ July 14 fly-by. We shall get very nice high resolutions of much of this hemisphere.

The other hemisphere, however, will not be facing us during the fly-by. Unless that can get some high resolution images before it rotates out of view, the row of large dark spots at the equator will remain a mystery.

The images also suggest that, because of Pluto’s tilt, much of the southern hemisphere is not going to be seen at all. It will remain an additional mystery for the many decades that are going to pass before another spacecraft finally returns to this distant place.

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Active sinkholes found on Comet 67P/C-G

11:00 am

pits on Comet 67P/C-G

Cool image time! Using Rosetta’s high resolution camera scientists have located a number of active pits similar to sinkholes on Earth on Comet 67P/C-G.

Based on the Rosetta observations, the team has proposed a model for the formation of these sinkholes. A source of heat beneath the comet’s surface causes ices (primarily water, carbon monoxide and carbon dioxide) to sublimate. The voids created by the loss of these ice chunks eventually grow large enough that their ceilings collapse under their own weight, giving rise to the deep, steep-sided circular pits seen on the surface of comet 67P/Churyumov-Gerasimenko.

The collapse exposes comet ices to sunlight for the first time, which causes the ice chunks to begin sublimating immediately. These deeper pits are therefore thought to be relatively young. Their shallower counterparts, on the other hand, are most likely older sinkholes with more thoroughly eroded sidewalls and bottoms that have been filled in by dust and ice chunks.

Essentially, they have found that decay of the comet’s nucleus has been mostly gentle and steady, rather than explosive, punctuated with sudden abrupt events.

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New Horizons gets closer

11:30 pm

Pluto and Charon

Cool image time! Even as the engineers successfully completed last night their last course correction engine burn, the New Horizons science team released an image showing both Pluto and Charon.

The 23-second thruster burst was the third and final planned targeting maneuver of New Horizons’ approach phase to Pluto; it was also the smallest of the nine course corrections since New Horizons launched in January 2006. It bumped the spacecraft’s velocity by just 27 centimeters per second – about one-half mile per hour – slightly adjusting its arrival time and position at a flyby close-approach target point approximately 7,750 miles (12,500 kilometers) above Pluto’s surface.

The image, which I have cropped to focus on the planets, is still somewhat fuzzy, though it also shows the increasing sharpness as the spacecraft gets closer.

Only two weeks to go!

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Another Dawn image of some of Ceres’ bright spots

10:37 am

The double bright spot, not over-exposed

Cool image time! As part JPL’s regular release of images from Dawn, one image of Ceres’ bright double spots was purposely not over-exposed. Thus, the surface is almost black (as it really looks), while the small cluster of spots stands out brightly but with some additional detail. (If you download the full image and use a graphics program to brighten it you will see that this is the double bright spot located inside a large crater.)

I have cropped and enlarged the original image to focus on the double spot. As you can see the brightest spot has a mottled look, almost like we are looking down at a snow-capped peak.

Though the leading theory remains that this is ice, this theory has not been confirmed yet. Make no assumptions or you may discover you are wrong.

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An update on Rosetta’s effort to re-establish contact with Philae

8:47 am

This update describes the status of the effort by the Rosetta science team to re-establish a stable communications channel with the Philae lander on the surface of Comet 67P/C-G.

Confirmed contacts between Rosetta and Philae have been made on 13, 14, 19, 20, 21, 23, and 24 June, but were intermittent during those contact periods. For example, the contact on 19 June was stable but split into two short periods of two minutes each. Conversely, the contact on 24 June started at 17:20 UT (on board Rosetta) and ran for 20 minutes, but the quality of the link was very patchy and only about 80 packets of telemetry were received. Prior to this, on Tuesday, 23 June, there was a 20-second contact, but no stable link was established and consequently no telemetry data were received.

There are many reasons why the contacts have been so intermittent, much of it related to Philae’s position on the surface. To improve things, they are carefully adjusting Rosetta’s position relative to the comet while avoiding placing the spacecraft in a position where the coma’s dust will cause problems.

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Black hole awakes after 26 years

10:44 am

For the first time since 1989, the black hole in V404 Cygni, a system comprising a black hole and a star, has reawakened, suddenly emitting high energy outbursts beginning on June 15.

First signs of renewed activity in V404 Cygni were spotted by the Burst Alert Telescope on NASA’s Swift satellite, detecting a sudden burst of gamma rays, and then triggering observations with its X-ray telescope. Soon after, MAXI (Monitor of All-sky X-ray Image), part of the Japanese Experiment Module on the International Space Station, observed an X-ray flare from the same patch of the sky.

These first detections triggered a massive campaign of observations from ground-based telescopes and from space-based observatories, to monitor V404 Cygni at many different wavelengths across the electromagnetic spectrum.

The outbursts are probably occurring because the black hole is gobbling up material that has fallen into it.

While the 1989 outburst helped astronomers gain their first understand of the behavior of a black hole in a star system, this outburst will help them understand how such systems evolve and change over time.

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Finding Pluto is really New Horizon’s biggest problem

9:59 am

As New Horizons speeds towards its planned fly-by of Pluto on July 14, the biggest problem faced by its engineers is making sure the spacecraft actually finds and photographs the planet.

Because astronomers discovered the dwarf planet in 1930, they have seen only part of its 248-year path around the Sun, and they don’t know exactly where Pluto is. And New Horizons is so far from Earth that it takes 9 hours to send and receive a signal, making the spacecraft hard to direct in real time. “Everything is pushed to the extreme,” says Bobby Williams, an engineer at KinetX Aerospace in Simi Valley, California, who heads the mission’s navigation team.

This fact, which has not been mentioned previously as far as I remember, suggests that there is a good chance that New Horizons might fly through its planned window and aim its cameras at the wrong spot in the sky, missing Pluto entirely. It also explains partly why the images released so far have been so fuzzy: They are focused mostly on doing navigation work, and are taking wide angle shots to make sure they catch Pluto in their picture frame. Zooming in too close might actually miss Pluto as they don’t exactly know where it is.

All this only makes the July 14th fly-by even more exciting. Let us hope they do due diligence and get the pictures we all want!

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Hawaii governor halts TMT construction again

9:30 am

In a very vague statement the governor of Hawaii has once again stopped construction of the Thirty Meter Telescope (TMT) while he reassesses the situation after protesters yesterday blocked the road to the mountain summit with boulders.

“We are disappointed and concerned that large boulders were found in the roadway leading to the summit of Mauna Kea,” McCartney said in the statement. “This action is a serious and significant safety hazard and could put people at risk. “Because of this, we are making an assessment to determine how to proceed,” he said. “We will be working to clear the roadway tomorrow. Therefore, construction is on hold until further notice.”

The statement implies that he is trying to figure out a way to prevent the protesters from blocking the road, without causing more conflict. I instead suspect he sympathies with the protesters, and is looking for a way to stop construction, which he legally cannot do.

If the road is not reopened by the end of this week and construction is still blocked, I think the TMT managers, as well as the operators of the other telescopes on the mountain, should seriously consider moving from Hawaii. I also repeat that a boycott of Hawaiian tourism might also be appropriate now. This is what these nativist activists want, no more outsiders. We should give them what they want.

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The icy patches on Comet 67P/C-G

8:48 am

Data from Rosetta’s high resolution camera have identified more than a hundred small patches of ice on the surface of Comet 67P/C-G.

Some of these bright features are found in clusters, while others appear isolated, and when observed at high resolution, many of them appear to be boulders displaying bright patches on their surfaces.

The clusters of bright features, comprising a few tens of metre-sized boulders spread over several tens of metres, are typically found in debris fields at the base of cliffs. They are most likely the result of recent erosion or collapse of the cliff wall revealing fresher material from below the dust-covered surface.

By contrast, some of the isolated bright objects are found in regions without any apparent relation to the surrounding terrain. These are thought to be objects lifted up from elsewhere on the comet during a period of cometary activity, but with insufficient velocity to escape the gravitational pull of the comet completely.

Most of the images from Rosetta’s high resolution camera have been held back so that the project scientists could publish their papers from the data. This release is in conjunction with one of those papers [pdf].

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New images of Pluto

12:06 pm

Latest Pluto images

Cool image time! The two images on the right, taken on June 18 and June 15 respectively, — cropped from a larger collection — show Pluto’s two hemispheres, as best as New Horizons can at the moment resolve them.

While still as fuzzy as pre-space age planetary images, the pictures when compared with earlier images of the same hemispheres now clearly show several consistent features.

Things can only get better. Stay tuned!

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When to doubt a scientific consensus

9:39 am

Link here.

This is a beautifully written and thoughtful analysis of the state of climate science, and why intelligent and educated citizens should continue to remain skeptical of the claims coming from the global warming activist community (which now includes the Pope).

He gives a dozen different reasons for remaining skeptical of the claims of the global warming community, based both on the science as well as how they sell their position. Number 10 — “When [the claimed consensus] it is being used to justify dramatic political or economic policies” — is probably the most important:

Imagine hundreds of world leaders and nongovernmental organizations, science groups, and United Nations functionaries gathered for a meeting heralded as the most important conference since World War II, in which “the future of the world is being decided.” These officials seem to agree that institutions of “global governance” need to be established to reorder the world economy and massively restrict energy resources. Large numbers of them applaud wildly when socialist dictators denounce capitalism. Strange philosophical and metaphysical activism surrounds the gathering. And we are told by our president that all of this is based, not on fiction, but on science — that is, a scientific consensus that human activities, particularly greenhouse gas emissions, are leading to catastrophic climate change.

We don’t have to imagine that scenario, of course. It happened in Copenhagen, in December 2009. It will happen again in Paris, in December 2015.

Now, none of this disproves the hypothesis of catastrophic, human induced climate change. But it does describe an atmosphere that would be highly conducive to misrepresentation. And at the very least, when policy consequences, which claim to be based on science, are so profound, the evidence ought to be rock solid. “Extraordinary claims,” the late Carl Sagan often said, “require extraordinary evidence.” When the megaphones of consensus insist that there’s no time, that we have to move, MOVE, MOVE!, you have a right to be suspicious.

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A closer close-up of Ceres’ double bright spot

9:19 am

Closer look at Ceres' double bright spot

Cool image time! In a new press release, the Dawn science team has unveiled a new close-up of Ceres’ double bright spot, shown on the right.

At least eight spots can be seen next to the largest bright area, which scientists think is approximately 6 miles (9 kilometers) wide. A highly reflective material is responsible for these spots — ice and salt are leading possibilities, but scientists are considering other options, too.

In other words, they still have not confirmed through spectroscopy, that these bright spots are ice.

Note also that they have reduced the image’s brightness so that the bright spots do not over expose as much as in past images. This not only allows more details to come out, but it portrays Ceres’ very dark surface more accurately. Even so, the image still shows that surface as brighter than it actually is.

A mountain on Ceres

The press release also described a second image, showing a single lonely mountain on the planet’s horizon, rising up three miles from the planet’s surface, shown in the cropped image to the left. Overall this image, as well as the others, suggest that the surface of Ceres is generally far less rough than we should expect.

Another science mystery to unravel!

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Active lava flows found on Venus

9:10 am

volcanoes on Venus

Cool image time! Using archival data from Venus Express, scientists have identified several spots on Venus where it appears there are active lava flows.

Using a near-infrared channel of the spacecraft’s Venus Monitoring Camera (VMC) to map thermal emission from the surface through a transparent spectral window in the planet’s atmosphere, an international team of planetary scientists has spotted localised changes in surface brightness between images taken only a few days apart. “We have now seen several events where a spot on the surface suddenly gets much hotter, and then cools down again,” says Eugene Shalygin from the Max Planck Institute for Solar System Research (MPS) in Germany, and lead author of the paper reporting the results in Geophysical Research Letters this month. “These four ‘hotspots’ are located in what are known from radar imagery to be tectonic rift zones, but this is the first time we have detected that they are hot and changing in temperature from day to day. It is the most tantalising evidence yet for active volcanism.”

The hotspots are found along the Ganiki Chasma rift zone close to the volcanoes Ozza Mons and Maat Mons. Rift zones are results of fracturing of the surface, which is often associated with upwelling of magma below the crust. This process can bring hot material to the surface, where it may be released through fractures as a lava flow.

There have been hints of volcanic activity on Venus since Pioneer Venus Orbiter first circled the planet from 1978 to 1992. This appears to be the first solid evidence of it.

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Astronomers have discovered an exoplanet smaller than Earth

11:45 am

Worlds without end: Scientists have measured the size and mass of the smallest exoplanet yet, a Mars-sized planet orbiting a star about 200 light years away.

The planet, named Kepler-138 b, is the first exoplanet smaller than the Earth to have both its mass and its size measured. It is one of three planets that orbit the star Kepler-138 and that pass in front of it on every orbit as viewed from Earth — a maneuver that astronomers call a transit. “Each time a planet transits the star, it blocks a small fraction of the star’s light, allowing us to measure the size of the planet,” said Dr. Daniel Jontof-Hutter, a research associate in astronomy at Penn State who led the study.

“We also measured the gravity of all three planets, using data from NASA’s Kepler mission, by precisely observing the times of each transit,” Jontof-Hutter said. The astronomers also were able to measure the masses of these planets. “Each planet periodically slows down and accelerates ever so slightly from the gravity of its neighboring planets. This slight change in time between transits allowed us to measure the masses of the planets,” Jontof-Hutter explained. After measuring both the mass and size of an exoplanet, astronomers then can calculate its density and its bulk composition.

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Rosetta repositions to improve contact with Philae

8:52 am

Engineers have begun shifting Rosetta’s trajectory paralleling Comet 67P/C-G in order to maximize communications with the lander Philae.

Commands to adjust the trajectory were successfully uploaded Monday evening; further commands will be uplinked on Thursday evening. The spacecraft will perform two manoeuvres, one on Wednesday morning and the second on Saturday morning. The effect of the two ‘dog-leg’ burns will be to bring the orbiter to a distance of 180 km from the comet and to reproduce the orbiter-comet geometry of the first contact.

We should therefore not expect further news from Philae for the rest of this week.

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Another successful course correction for New Horizons

9:31 pm

New Horizons has successfully completed another course correction and is shipshape for its fly-by of Pluto on July 14.

A 45-second thruster burst on June 14 refined New Horizons’ trajectory toward Pluto, targeting the optimal aim point for the spacecraft’s flight through the Pluto system. This was only the second targeting maneuver of New Horizons’ approach to Pluto; Sunday’s burst adjusted the spacecraft’s velocity by just 52 centimeters per second, aiming it toward the desired close-approach target point approximately 7,750 miles above Pluto’s surface.

The maneuver was based on the latest radio tracking data on the spacecraft and range-to-Pluto measurements made by optical-navigation imaging of the Pluto system taken by New Horizons in recent weeks.

Right now all looks good for the fly-by.

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