The Sun shows a bit of life

It is that time again, buckos! Yesterday NOAA released its monthly update of the Sun’s sunspot cycle, covering the period of April 2013. As I have done every month for the past three years, I have posted this latest graph, with annotations to give it context, below the fold.

For the second month in a row the Sun’s sunspot output increased. The result is that April 2013 saw the most sunspot activity in more than a year, since December 2011.

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A solar-powered airplane landed safely in Phoenix today on its first leg of an attempt to fly across the United States.

A solar-powered airplane landed safely in Phoenix today on its first leg of an attempt to fly across the United States.

I totally support this effort to develop new technology, but must note that the capabilities of this solar-powered plane, as described in this article, are woefully limited. Nonetheless, I can see many applications where these liabilities will not be an issue, so all power to them. I hope they succeed.

The high peak in tornado in 2011, the most in fifty years, was quickly attributed to global warming. Eric Berger asks: How does this explain this year’s low number, the fewest in fifty years?

The uncertainty of science: The high peak in tornado in 2011, the most in fifty years, was quickly attributed to global warming. Eric Berger asks: How does this explain this year’s low number, the fewest in fifty years?

If you click on the first link, you will see that the global warming scientists quoted, Kevin Trenberth, Michael Mann, and Gavin Schmidt, were all involved in the climategate emails, where they came off very badly. Moreover, there have been significant questions about the work of Michael Mann himself. I also wonder if these guys will have anything to say about the dearth of tornadoes today.

The lingering echo of Comet Shoemaker-Levy in the atmosphere of Jupiter.

The lingering echo of Comet Shoemaker-Levy in the atmosphere of Jupiter.

The Herschel observations, together with heat maps provided by NASA’s Infrared Telescope Facility on Mauna Kea, showed the researchers that the Jovian stratosphere was 20° to 30°F (10° to 15°C) warmer than it would be if completely dry. One question is whether the stratospheric warming results from the gentle, continuous infall of interplanetary dust particles, which would be warmed by sunlight as they linger high up. Cavalié and his colleagues believe IDPs create some of the infrared emission but cannot explain it all. Further, a continuously supplied source would migrate to lower depths, yet most of the emission is too high up, at pressures less than 2 millibars. And while the amount of water is roughly constant across the southern hemisphere, the emission gradually weakens northward until it’s less than half as strong. It’s not simply that Jupiter’s bottom half is hotter — there’s just more water down there. As the researchers note, “At least 95% of the observed water comes from the SL9 comet and subsequent (photo)-chemistry in Jupiter’s stratosphere according to our models, as of today.

Taken together, they conclude, these observations offer “clear evidence that a recent comet … is the principal source of water in Jupiter. What we observe today is a remnant of the oxygen delivery by the comet at 44°S in July 1994.”

The Chinese national who had been arrested at Dulles airport as he left for China with a NASA laptop has been released after pleading guilty to one charge, having porn on the laptop.

The Chinese national who had been arrested at Dulles airport as he left for China with a NASA laptop has been released after pleading guilty to one charge, having porn on the laptop.

Investigators found no classified information on the computer. As part of the release agreement, however, the man must leave the U.S.

Though the man, Bo Jiang, was very careful to bring nothing secret with him when he tried to flee to China in March, the circumstantial evidence suggests that he should not have had access to this information in the first place, and that in the past he might have illegally funneled classified information to China.

NASA revealed Tuesday that last April the Fermi Gamma-Ray Telescope barely avoided a collision with an abandoned Russian satellite.

NASA revealed Tuesday that last April the Fermi Gamma-Ray Telescope barely avoided a collision with an abandoned Russian satellite.

Fermi mission scientists first learned of the space collision threat on March 29, 2012 when they received a notice that the space telescope and Cosmos 1805 would miss each other by just 700 feet (213.4 meters). The mission team monitored the situation over the next day and it became clear that the two spacecraft, traveling in different orbits, would zip through the same point in space within 30 milliseconds of one another, NASA officials said.

They used Fermi’s thrusters to shift its orbit enough so the two spacecraft missed each other by 6 miles.

Opportunity went into safe mode during the communications pause in April when the Sun was between Mars and the Earth.

Opportunity went into safe mode during the communications pause in April when the Sun was between Mars and the Earth.

Mission controllers for Opportunity, which landed on Mars in January 2004, first learned of the issue on Saturday (April 27). On that day, the rover got back in touch after a nearly three-week communication moratorium caused by an unfavorable planetary alignment called a Mars solar conjunction, in which Mars and Earth are on opposite sides of the sun. The Opportunity rover apparently put itself into standby on April 22 after sensing a problem during a routine camera check, mission managers said.

It sounds like this is a recoverable problem and the rover will be back in operation momentarily. Stay tuned.

Three years of Solar Dynamics Observatory images of the Sun — in three minutes.

Three years of Solar Dynamics Observatory images of the Sun — in three minutes.

I’ve posted the video below the fold. It’s quite cool.

Note that these images cover the period when the Sun was ramping up to what was hoped to be a strong solar maximum, when SDO was being designed and built. And though the Sun does appear to be active in these images, it is actually far less active than it has been for solar maximums going back at least a century.

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An detailed analysis of the tumbling of the asteroid Apophis, detected by radar observations in January, suggests it will be easier to predict the asteroid’s orbit in the future.

The sky isn’t falling: A detailed analysis of the tumbling of the asteroid Apophis, detected by radar observations in January, suggests it will be easier to predict the asteroid’s orbit in the future.

The gentle but persistent nudging [of the Yarkovsky effect] arises when sunlight is absorbed by a rotating object and then reradiated as heat in some other direction. In particular, if Apophis were spinning retrograde (opposite the way Earth does), then over time its orbit would change in a way that increases the chance of impact in 2036. But now we can rest easy, because Apophis appears to be tumbling as it orbits the Sun. That’s the conclusion reached by a team of telescopic observers who monitored the asteroid’s light curve as it passed near Earth in January. Apophis is spinning around two axes at the same time, implying that any Sun-warmed surfaces are radiating heat in all directions, not just one in particular.

It is very difficult to measure the Yarkovsky effect, thus making it very difficult to precisely calculate the orbits of many near Earth asteroids. In the case of Apophis, however, it appears the astronomers have gotten a good handle on the problem.

Hubble has taken a spectacular close-up image of the Horsehead Nebula.

A horsehead of another color: Hubble has taken a spectacular close-up image of the Horsehead Nebula.

Also, if you want to find out exactly how powerful Hubble is in comparison with both ground-based and other space telescopes, check out the video provided by this press release for the new images by the Herschel Space Telescope of the Horsehead Nebula that were also released today. Herschel, which works in the far-infrared, produces good data and information that Hubble cannot, but its imagery cannot compare.

Using Kepler astronomers have found a solar system with five terrestrial-type planets, with two in the habitable zone.

Eden? Using Kepler astronomers have found a solar system with five terrestrial-type planets, with two in the habitable zone.

Using observations gathered by NASA’s Kepler Mission, the team, led by William Borucki of the NASA Ames Research Center, found five planets orbiting a Sun-like star called Kepler-62. Four of these planets are so-called super-Earths, larger than our own planet, but smaller than even the smallest ice giant planet in our Solar System. These new super-Earths have radii of 1.3, 1.4, 1.6, and 1.9 times that of Earth. In addition, one of the five was a roughly Mars-sized planet, half the size of Earth. …

The two super-Earths with radii of 1.4 and 1.6 Earth radii orbit their star at distances where they receive about 41% and 120%, respectively, of the warmth from their star that the Earth receives from the Sun. The planets are thus in the star’s habitable zone; they have the right temperatures to maintain liquid water on their surfaces and are theoretically hospitable to life.

Theoretical modeling of the super-Earth planets, Kepler-62e and Kepler-62f, suggests that both could be solid, either rocky–or rocky with frozen water.

This is big news. Additional info can be found here and here.

The International Astronomical Union has issued a press release condemning the commercial efforts of private companies to issue names for exoplanets.

Turf war! The International Astronomical Union has issued a press release condemning the commercial efforts of private companies to issue names for exoplanets.

Recently, an organisation has invited the public to purchase both nomination proposals for exoplanets, and rights to vote for the suggested names. In return, the purchaser receives a certificate commemorating the validity and credibility of the nomination. Such certificates are misleading, as these campaigns have no bearing on the official naming process — they will not lead to an officially-recognised exoplanet name, despite the price paid or the number of votes accrued.
… [snip]
To make this possible, the IAU acts as a single arbiter of the naming process, and is advised and supported by astronomers within different fields. As an international scientific organisation, it dissociates itself entirely from the commercial practice of selling names of planets, stars or or even “real estate” on other planets or moons. These practices will not be recognised by the IAU and their alternative naming schemes cannot be adopted.

Well la-dee-da, how dare anyone else name anything ever in space!

The truth is, the IAU was originally given this function by astronomers to coordinate the naming of obscure astronomical objects, not to provide the official names for every object and feature that will ever be discovered in space. And though the IAU does tend to favor the choices of discoverers, it has in the past also ignored their wishes. (See for example my book Genesis: the Story of Apollo 8, where the IAU rejected the names chosen by the Apollo 8 astronauts, even though those astronauts were the first to actually go and see these features.)

In the end, the names of important features in space will be chosen by those who live there.

Despite a rest, Kepler’s problematic gyroscope is still having problems.

Despite a rest, Kepler’s problematic gyroscope is still having problems.

Three of the wheels are needed for Kepler’s 3.1-foot telescope to have enough sensitivity to detect the minuscule signatures of Earth-sized planets. In an exercise of caution, mission managers switched off Kepler’s reaction wheels for 10 days in January, hoping the break would redistribute lubricant inside the wheel assemblies, reducing friction and allowing the units to cool down.

But friction in wheel no. 4, which has showed friction for much of Kepler’s mission, actually increased in the month following the “wheel rest” period.

The telescope originally had four wheels. One has failed, with a second showing signs of failure. If it goes, the spacecraft will no longer be able to point with enough accuracy to do its primary mission. They might be able to use it to some observations, but its design is such that even these will be of limited value.

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