Tag: science

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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Flashback to ABC’s 2008 climate predictions for 2015

11:53 am

Working for leftist global warming activist community and the Democratic Party (but I repeat myself): In 2008 ABC News did a special on what global warming was going to do to the climate in the coming years, and predicted disaster by June 2015.

New York City underwater? Gas over $9 a gallon? A carton of milk costs almost $13? Welcome to June 12, 2015. Or at least that was the wildly-inaccurate version of 2015 predicted by ABC News exactly seven years ago. Appearing on Good Morning America in 2008, Bob Woodruff hyped Earth 2100, a special that pushed apocalyptic predictions of the then-futuristic 2015. The segment included supposedly prophetic videos, such as a teenager declaring, “It’s June 8th, 2015. One carton of milk is $12.99.” (On the actual June 8, 2015, a gallon of milk cost, on average, $3.39.) Another clip featured this prediction for the current year: “Gas reached over $9 a gallon.” (In reality, gas costs an average of $2.75.)

On June 12, 2008, correspondent Bob Woodruff revealed that the program “puts participants in the future and asks them to report back about what it is like to live in this future world. The first stop is the year 2015.” As one expert warns that in 2015 the sea level will rise quickly, a visual shows New York City being engulfed by water. The video montage includes another unidentified person predicting that “flames cover hundreds of miles.” Then-GMA co-anchor Chris Cuomo appeared frightened by this future world. He wondered, “I think we’re familiar with some of these issues, but, boy, 2015? That’s seven years from now. Could it really be that bad?”

ABC is also the same network that sees nothing wrong with its main news anchor, George Stephanopolos, giving tens of thousands of dollars to aid the presidential campaign of Democrat Hillary Clinton. Think of these details the next time you see any news reporting from them.

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New images from New Horizons of Pluto

7:29 pm

Images taken by New Horizons over a four day period at the end of May show Pluto to be a planet with distinct areas of bright and dark.

The images are still very fuzzy and require a great deal of processing to tease out the detail that is seen. If anything, they resemble images of Mars taken from Earth before the space age. Thus, one must treat these the dark and light areas with great skepticism. We are seeing evidence of different surface topography and geology, but to pin it down more precisely at this time would be a mistake. The spacecraft has to get closer for us to know better what we are seeing.

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Is this Philae?

9:14 am

Philae?

Cool image time! The Rosetta science team has spent much effort trying to locate Philae, which attempted to land on Comet 67P/C-G in November. The image on the right shows what they think is their best candidate, the bright feature in the center. It was not there prior to Philae’s landing attempt.

Because there are many uncertainties, however, this might not be Philae.

Ultimately, a definitive identification of this or any other candidate as being Philae will require higher-resolution imaging, in turn meaning closer flybys. This may not be possible in the near-term, as issues encountered in navigating close to the comet mean that the opportunity to make flybys at significantly less than 20 km from the surface may be on hold until later in the mission. But after the comet’s activity has subsided, Rosetta should be able to safely operate in close proximity to the comet nucleus again.

The other possibility of further refining Philae’s location would come if the lander were to receive enough power to wake-up from its hibernation and resume its scientific study of 67P/C-G. Then, CONSERT could be used to perform additional ranging measurements and significantly reduce the uncertainties on the lander’s location. At the moment, Philae is still in hibernation, but the mission team remain hopeful that, as the comet moves closer to the Sun along its orbit, the lander will receive enough power in the coming weeks or months to wake up and transmit a signal to Rosetta.

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The truth about bottled water

6:01 pm

An evening pause: Tonight’s pause is a bit different, in that it has a newsy aspect to it, illustrating the uncertainty of knowledge that makes science so difficult. It is also incredibly entertaining and funny, almost like the 1960s TV show Candid Camera. Would you be fooled like these people were?

Hat tip Phillip Oltmann.

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New close-up image of Ceres’s double bright spots

9:32 am

close-up of Ceres's bright spots

Cool image time! The Dawn science team has released a some new close-up images of Ceres, including a much higher resolution image of the dwarf planet’s double bright spot, which now resolves itself into a cluster of two larger spots with a half dozen smaller spots scattered nearby.

The region with the brightest spots is in a crater about 55 miles (90 kilometers) across. The spots consist of many individual bright points of differing sizes, with a central cluster. So far, scientists have found no obvious explanation for their observed locations or brightness levels.

“The bright spots in this configuration make Ceres unique from anything we’ve seen before in the solar system. The science team is working to understand their source. Reflection from ice is the leading candidate in my mind, but the team continues to consider alternate possibilities, such as salt. With closer views from the new orbit and multiple view angles, we soon will be better able to determine the nature of this enigmatic phenomenon,” said Chris Russell, principal investigator for the Dawn mission based at the University of California, Los Angeles.

To my eye, these bright areas resemble a wide flat caldera of a volcano. Instead of being at the top of a peak, the caldera is like a lava pool, almost like a large lake. In this case, the large spots are lakes of frozen ice that periodically melt and flow. The smaller spots are likely smaller vents where water can bubble up from below during active periods. When not active, the water will be frozen. Since ice is white and Ceres is very dark, the pools and vents appear extremely bright in these images.

I am speculating however. We will have to wait for much better images to know for sure.

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The collapse of Russian scientific innovation

9:13 am

Link here. This report documents much of what I have been seeing in the Russian space industry: an aging workforce, a lack of innovation, and concentration of power to Moscow and the central government, and an exodus of the best minds to other countries.

It appears that all of the solutions that have been imposed by Putin’s government are exactly the worst things you could do and will only make the problems grow with time.

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Finding caves on Mars

5:40 pm

A new study of pits on Mars has isolated one particular type of pit that has all the features of an Earth-like cave entrance, with a large number located in the regions around the giant volcanoes where evidence of past glacier activity has been found. From the abstract:

These Atypical Pit Craters (APCs) generally have sharp and distinct rims, vertical or overhanging walls that extend down to their floors, surface diameters of ~50–350 m, and high depth to diameter (d/D) ratios that are usually greater than 0.3 (which is an upper range value for impacts and bowl-shaped pit craters) and can exceed values of 1.8. Observations by the Mars Odyssey Thermal Emission Imaging System (THEMIS) show that APC floor temperatures are warmer at night and fluctuate with much lower diurnal amplitudes than nearby surfaces or adjacent bowl-shaped pit craters.

In other words, these pits are deeper with steeper and overhanging walls that suggest underlying passages. They also maintain warmer temperatures at night with their day/night temperatures changing far less than the surface, similar to caves on Earth where the cave temperature remains the same year-round.

The study’s most important finding, from my perspective, was the location of these pit craters.
» Read more

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Did some dinosaur soft tissues survive fossilization?

2:36 pm

The uncertainty of science: New research strongly suggests that within dinosaur fossils are found many preserved soft tissues from when the creature was still living.

As early as the 1970s, researchers captured images of what looked like cellular structures inside dinosaur fossils. But did the structures contain actual tissue? Proteins commonly decay hundreds to thousands of years after an organism dies, but in rare cases they have been known to survive up to 3 million years. In a series of studies beginning a decade ago, a team led by North Carolina State University paleontologist Mary Schweitzer reported that they had extracted what appeared to be collagen, the most abundant protein in bone, from a 68-million-year-old T. rex fossil. They sequenced fragments of the protein and concluded that it closely matched that of birds, dinosaurs’ living descendants (see here and here). But other teams haven’t been able to replicate the work, and others suggested that the collagen could be contamination.

The new study, led by materials scientist Sergio Bertazzo and paleontologist Susannah Maidment, both of Imperial College London, has a different strategy for hunting down ancient proteins. Bertazzo, an expert on how living bones incorporate minerals, uses a tool called a focused ion beam to slice through samples, leaving pristine surfaces that are ideal for high-resolution imaging studies. He teamed up with Maidment to apply the technique to eight chunks of dinosaur toe, rib, hip, leg, and claw.

What they found shocked them. Imaging the fresh-cut surfaces with scanning and transmission electron microscopes, “we didn’t see bone crystallites” as expected, Maidment says. “What we saw instead was soft tissue. It was completely unexpected. My initial response was these results are not real.” [emphasis mine]

It must be noted that the new research depends on many uncertainties that still need to be replicated or confirmed.

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$28 billion spent on poor biomedical research?

2:32 pm

The uncertainty of science: A new study suggests that $28 billion is spent on biomedical research that no one can reproduce.

I have no doubt that a vast amount of medical research is so poorly done that no one else will ever be able to replicate the results. However, the article notes that the way the researchers came up with the $28 billion figure is quite questionable, reviewing only about two dozen studies and then extrapolating their numbers across the entire research field. This is highly uncertain and should be taken with a grain of salt.

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Ramp down to solar minimum continues

12:11 pm

On Sunday NOAA posted its monthly update of the solar cycle, showing the Sun’s sunspot activity in May. As I have done since 2010, I am posting it here, with annotations to give it context.

May 2015 Solar Cycle graph

The graph above has been modified to show the predictions of the solar science community. The green curves show the community’s two original predictions from April 2007, with half the scientists predicting a very strong maximum and half predicting a weak one. The red curve is their revised May 2009 prediction.

Sunspot activity once again increased in May, though it continues to remain below the 2009 prediction of activity. Though it is still early in the ramp down, a look at the present pattern suggests that (as I also noted last month) sunspot activity is declining much faster than normal. In the past, the ramp down after solar maximum was long and drawn out, while ramp up was much faster. This ramp down seems much more precipitous than past solar cycles.

I should add that in early April Sunspot Index and Long-term Solar Observations (SILSO) had declared that the peak of the solar maximum had occurred in April 2014, and that they could now sum up the overall weakness of this maximum.

Cycle 24 proves to be 30% weaker than the previous solar cycle, which reached 119.7 in July 2000, and thus belongs to the category of moderate cycles, like cycles 12 to 15, which were the norm in the late 19th and early 20th century. Compared to strong cycles, such cycles typically feature a broader maximum, with a 3-year plateau on top of which two or more surges of activity can produce sharp peaks of similar height.

I had missed this announcement when it was first posted. It is worth noting however, especially since their discussion in April is interesting to read in the context of what has happened since.

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