Will Dawn head to another asteroid?

4:31 pm

NASA is still reviewing the proposal by the Dawn science team that they send the spacecraft to another asteroid in its last years before its fuel runs out.

The spacecraft has continued operations despite problems with its reaction wheels, used for attitude control. After suffering the loss of two of its four reaction wheels earlier in the mission, a third wheel malfunctioned in April. The spacecraft went into safe mode briefly, but controllers resumed operations with hydrazine thrusters taking over for the failed wheel. That failure will eventually lead to the end of the mission when the spacecraft runs out of hydrazine. “It does reduce our lifetime because we have to use hydrazine at a faster rate,” Raymond said at the SBAG meeting in June.

That lifetime, she said, is dependent on the spacecraft’s orbital altitude. Dawn has spiraled out to a higher orbit during its extended mission, which reduces the amount of hydrazine needed for attitude control. “The lifetime is now highly dependent on orbital altitude because we need to use the jets to fight the gravity gradient torques,” she said. In its current high orbit, Raymond said that Dawn had sufficient hydrazine, as well as xenon propellant used for the ion engine, to operate at least through the end of 2018.

5 comments

Five satellite Air Force contract up for bid

4:26 pm

Capitalism in space: The Air Force has announced that it will be soliciting bids from SpaceX and ULA for a 5-satellite launch contract.

Claire Leon, director of the Launch Enterprise Directorate at the Air Force’s Space and Missile Systems Center, told reporters that grouping launches together was an effort to streamline and speed the acquisition process at a time when the national security sector is demanding ever-increasing access to space. “By doing five at once, it makes our acquisition more efficient and it allows the contractors to put in one proposal,” she said.

This grouping however might make it impossible for SpaceX to win the contract, as the company’s Falcon 9 rocket might not be capable of launching all five satellites, and its Falcon Heavy has not yet flown the three times necessary before the Air Force will consider using it.

6 comments

Genesis cover

On Christmas Eve 1968 three Americans became the first humans to visit another world. What they did to celebrate was unexpected and profound, and will be remembered throughout all human history. Genesis: the Story of Apollo 8, Robert Zimmerman's classic history of humanity's first journey to another world, tells that story, and it is now available as both an ebook and an audiobook, both with a foreword by Valerie Anders and a new introduction by Robert Zimmerman.

 

The print edition can be purchased at Amazon or any other book seller. If you want an autographed copy the price is $60 for the hardback and $45 for the paperback, plus $8 shipping for each. Go here for purchasing details. The ebook is available everywhere for $5.99 (before discount) at amazon, or direct from my ebook publisher, ebookit you don't support the big tech companies and the author gets a bigger cut much sooner.


The audiobook is also available at all these vendors, and is also free with a 30-day trial membership to Audible.
 

"Not simply about one mission, [Genesis] is also the history of America's quest for the moon... Zimmerman has done a masterful job of tying disparate events together into a solid account of one of America's greatest human triumphs."--San Antonio Express-News

Fastest stars in Milky Way escaped from Large Magellanic Cloud?

9:01 am

Astronomers have proposed that the fastest stars in Milky Way actually escaped from the Large Magellanic Cloud (LMC), the largest nearby satellite dwarf galaxy.

The LMC is the largest and fastest of the dozens of dwarf galaxies in orbit around the Milky Way. It only has 10% of the mass of the Milky Way, and so the fastest runaways born in this dwarf galaxy can easily escape its gravity. The LMC flies around the Milky Way at 400 kilometres per second and, like a bullet fired from a moving train, the speed of these runaway stars is the velocity they were ejected at plus the velocity of the LMC. This is fast enough for them to be the hypervelocity stars. “These stars have just jumped from an express train – no wonder they’re fast,” said co-author Rob Izzard, a Rutherford fellow at the Institute of Astronomy. “This also explains their position in the sky, because the fastest runaways are ejected along the orbit of the LMC towards the constellations of Leo and Sextans.”

Their calculations predict how many hypervelocity stars should be detectable and where in the sky they should be. If right, the data from Gaia, soon to be released, should prove them right or wrong.

2 comments

Conscious Choice cover

Now available in hardback and paperback as well as ebook!

 

From the press release: In this ground-breaking new history of early America, historian Robert Zimmerman not only exposes the lie behind The New York Times 1619 Project that falsely claims slavery is central to the history of the United States, he also provides profound lessons about the nature of human societies, lessons important for Americans today as well as for all future settlers on Mars and elsewhere in space.

 
Conscious Choice: The origins of slavery in America and why it matters today and for our future in outer space, is a riveting page-turning story that documents how slavery slowly became pervasive in the southern British colonies of North America, colonies founded by a people and culture that not only did not allow slavery but in every way were hostile to the practice.  
Conscious Choice does more however. In telling the tragic history of the Virginia colony and the rise of slavery there, Zimmerman lays out the proper path for creating healthy societies in places like the Moon and Mars.

 

“Zimmerman’s ground-breaking history provides every future generation the basic framework for establishing new societies on other worlds. We would be wise to heed what he says.” —Robert Zubrin, founder of the Mars Society.

 

All editions are available at Amazon, Barnes & Noble, and all book vendors, with the ebook priced at $5.99 before discount. All editions can also be purchased direct from the ebook publisher, ebookit, in which case you don't support the big tech companies and the author gets a bigger cut much sooner.

 

Autographed printed copies are also available at discount directly from the author (hardback $29.95; paperback $14.95; Shipping cost for either: $6.00). Just send an email to zimmerman @ nasw dot org.

Qatar blockade threatens worldwide helium supply

8:54 am

The recent blockade imposed against Qatar by other Middle East countries, supposedly because of its support of terrorism, threatens the world’s supply of helium.

Qatar is the world’s largest exporter of helium and its second-largest producer, accounting for 25% of global demand (see ‘Helium supplies’). So the blockade will inevitably cause shortfalls over the next few months, says Phil Kornbluth, a consultant based in Bridgewater, New Jersey, who specializes in the helium industry.

Countries likely to be most affected are those closest to Qatar. But Asian countries such as India, China, Japan, Taiwan and Singapore are also at risk. “But none of us are immune,” adds William Halperin, a researcher in low-temperature physics at Northwestern University in Evanston, Illinois.

The U.S. is the world’s largest producer of helium, producing about twice as much as Qatar. That production is for our local markets, while Qatar exports it worldwide.

One comment

1776 – Hatching an Egg

6:01 pm

An evening pause: I posted this last year for the Fourth of July. It is worth watching again, and again, and again. From the 1976 movie version of the 1972 musical, 1776. As I said last year, not only did the musical capture the essence of the men who made independency happen, it is also a rollicking and entertaining work of art.

One comment

Leaving Earth cover

Leaving Earth: Space Stations, Rival Superpowers, and the Quest for Interplanetary Travel, can be purchased as an ebook everywhere for only $3.99 (before discount) at amazon, Barnes & Noble, all ebook vendors, or direct from my ebook publisher, ebookit.

 

If you buy it from ebookit you don't support the big oppressive tech companies and I get a bigger cut much sooner.

 

Winner of the 2003 Eugene M. Emme Award of the American Astronautical Society.

 
"Leaving Earth is one of the best and certainly the most comprehensive summary of our drive into space that I have ever read. It will be invaluable to future scholars because it will tell them how the next chapter of human history opened." -- Arthur C. Clarke

A look at the war for independence

4:00 pm

For the Fourth of July. Link here. Key quote:

O’Donnell urged listeners to contemplate the incredible nation forged from Washington’s courage and humanity, mixed with the wisdom and intellect of the other Founding Fathers. He agreed with Marlow that it was amazing how much the Founders got right from the beginning. “They got it right in terms of how power is used and abused,” O’Donnell said, noting that modern Americans might be surprised how controversial the Bill of Rights was at the time. “Just putting power back to the people, it’s an incredible thing.”

“They were also paranoid, rightfully so, of a central government that would encroach upon the rights of citizens,” he continued. “These were citizen-soldiers. They didn’t want to have a situation where there was potential tyranny.”

One comment

“People were different, not only from Swedes, but from each other.”

3:00 pm

For the Fourth of July. Link here. Key quote:

I’m not sure if I can fully convey the cultural shock of going from Sweden to Dallas in the 1990s, or if it is even wise to try. Because how can I describe what it is to taste your very first doughnut or go to Toys R Us at that age [9 years old] and see row after row of wonderfully girly Barbie dolls? I came from the country of meh to the nation of yeah. And it was nothing short of magnificent.

I was lucky enough to spend my summers there, in the heart of Texas, and with every visit I gained a growing awareness of the differences between your country and mine. America was loud. It was uncomfortable and alive. People were different, not only from Swedes, but from each other. [emphasis in original]

4 comments

A close look at the first paragraph of the Declaration of Independence

11:30 am

For the Fourth of July: Link here. The author discusses it phrase by phrase, placing the words in their historical context so there will be no confusion. For anyone who is intellectually honest, however, I think the meaning is quite clear.

We hold these truths to be self-evident, that all men are created equal, that they are endowed by their Creator with certain unalienable Rights, that among these are Life, Liberty and the pursuit of Happiness. — That to secure these rights, Governments are instituted among Men, deriving their just powers from the consent of the governed, — That whenever any Form of Government becomes destructive of these ends, it is the Right of the People to alter or to abolish it, and to institute new Government, laying its foundation on such principles and organizing its powers in such form, as to them shall seem most likely to effect their Safety and Happiness.

21 comments

“It took two wars to make me an American.”

10:21 am

For the Fourth of July. Link here. Key quote:

My parents were born in the north, and when an international summit divided the country into communist North Vietnam and non-communist South Vietnam in 1954, their families were among a million who left all they owned to flee south away from Ho Chi Minh’s troops — troops whom my dad once had idolized as nationalist boy and girl scouts. Scouts honor no more. Escaping to America in ’75 was the second time my parents sacrificed the past to save their future. Second. Anything but communism.

Leave a comment

New data suggests Sun undergoing fundamental changes

8:40 am

The uncertainty of science: New data, when compared with similar data collected over decades, suggests the Sun’s solar cycle is undergoing some fundamental changes.

In work just published in the Monthly Notices of the Royal Astronomical Society, the team shows that the interior of the Sun has changed in recent years, and that these changes persist in the current cycle. In combination with theoretical models, the observations suggest that the magnetic field distribution in the outer layers may have become a bit thinner. Other seismic data shows that the rotation rate of the Sun has also undergone some changes in the way the Sun rotates at different latitudes.

“Again, this is not how it used to be and the rotation rate has slowed a bit at latitudes around about 60 degrees. We are not quite sure what the consequences of this will be but it’s clear that we are in unusual times. However, we are beginning to detect some features belonging to the next cycle and we can suggest that the next minimum will be in about two years,” says Elsworth.

First, they don’t know what will happen because of these changes. Second, their data confirms that the solar minimum will occur in about two years, which would make this cycle only 9 years long, one of the shortest but also one of the weakest that has been observed, two things that previously had never gone together.

3 comments

Becoming American

8:15 am

For the Fourth of July. Link here. Key quote:

The process of being an American goes on, though. As almost everyone here should be aware, being an American – not just fitting in the culture, and because that’s regional it means I’ll need to learn to talk and walk again if I move across the country again – is an ongoing process, an ongoing fight between liberty and totalitarian impulses which exist in every society and possibly in every human. And it is a struggle to free yourself from the inherited nonsense that has plagued other societies too: ideas of class and inherited rank or ability.

It is our solemn duty, no matter how many of our compatriots fail at it, to live up to our amazing luck in being citizens of the greatest nation on Earth, one founded on the belief that individuals can be self-governing and are the bosses of their own government.

One comment

World View test balloon flight cut short due to leak

9:10 pm

The first test flight of World View’s Stratollite balloon, planned for 4 days, was ended after only 17 hours because of a leak in the balloon.

Though the mission was the longest yet for the balloon, and though they managed to test the attitude control, communications, and solar power systems, they need to find out why the balloon did not hold pressure as expected before they can begin flying missions lasting from months to even a year.

Leave a comment

North Korea test fires another ballistic missile

7:01 pm

North Korea today launched another test missile into nearby waters, this time landing in Japanese waters.

Update: North Korea now claims this was an ICBM that could have reached Alaska, and some of the experts quoted appear to agree.

It was estimated to have reached an altitude that “greatly exceeded” 2,500 kilometres, Japan said, prompting arms control specialist Jeffrey Lewis to respond on Twitter: “That’s it. It’s an ICBM. An ICBM that can hit Anchorage not San Francisco, but still.”

David Wright, of the Union of Concerned Scientists, wrote on the organisation’s allthingsnuclear blog that the available figures implied the missile “could reach a maximum range of roughly 6,700 km on a standard trajectory. … That range would not be enough to reach the lower 48 states or the large islands of Hawaii, but would allow it to reach all of Alaska.”

27 comments

Sunspot update for June 2017

11:47 am

Today NOAA posted its monthly update of the solar cycle, covering sunspot activity for June. As I have done every month since 2010, the graph is posted below, with annotations.

June 2017 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 in June was almost exactly the same as in May, and thus continued the overall downward trend that is below the 2007 low prediction and that suggests that this very weak solar maximum will end much earlier than predicted, and will make it an unprecedented short but weak cycle. The Sun is once again blank today for the first time in about two weeks, repeating the pattern we have seen for several months where, because one hemisphere of the Sun is blank while the other hemisphere has some sunspots, the rise and fall of the sunspot counts tracks the 27-day solar rotation almost precisely.

There continues to be evidence that the Sun is undergoing significant changes this solar cycle, all of which are pointing to the possibility that a grand minimum is coming, with no sunspots for decades. And as I have said now monthly for six years, past grand minimums have consistently occurred at the same time the Earth’s climate has cooled. The scientific link remains unclear, but if we should undergo a grand minimum in the coming decades, we will finally have the opportunity to find out what that link is.

7 comments

The soft craters of Epimetheus

9:24 am

The soft craters of Epimetheus

Cool image time! The image on the right, reduced in resolution to show here, is the highest resolution image that Cassini has taken of the Saturn moon Epimetheus, taken from only 9,300 miles away on February 21, 2017.

Epimetheus (70 miles or 113 kilometers across) is too small for its gravity to hold onto an atmosphere. It is also too small to be geologically active. There is therefore no way to erase the scars from meteor impacts, except for the generation of new impact craters on top of old ones.

Below is the inset at full resolution, showing several craters, with ponds of dust on their floor. Overall, the surface of this tiny moon looks soft. The craters are all shallow, as if any impact merely plunged into a blob of ice cream. Any ejecta from those impacts eventually rained back down, and then settled slowly in the moon’s low points, forming those ponds of dust.

close-up of soft craters

In many ways this image is very revealing, as it shows what the early accretion process of any planetary body will look like. Nor is this unique. Earlier images taken of the asteroid Eros by the NEAR probe saw many of these same features, as have images of Saturn’s other small moons. In the early stages, new material gets absorbed easily because it finds it easy to bore into the body of the newly formed and not very dense planetary body. There isn’t much ejecta, and what there is doesn’t fly that far away so that it can settle back down on the surface and add to the new body’s total mass.

2 comments

Long March 5 failure occurred at satellite separation

8:57 am

This story notes that the failure of the Long March 5 launch occurred 30 minutes after launch, when the second stage and the satellite were due to separate.

The link also includes footage of the launch through first stage separation and ignition of second stage engines.

It appears therefore that the failure was not in the Long March 5 rocket itself. When satellite separation occurs the second stage has completed its work, so the rocket apparently did its job getting the satellite into orbit. What happened next however remains unknown.

Based on this information it would appear that this failure might not delay later launches of the Long March 5 that much.

12 comments

Reba McEntire -You can’t get a man with a gun

6:01 pm

An evening pause: From the Broadway musical Annie Get Your Gun. In January 2001, McEntire, a well known country singer, made her Broadway debut in the 2000 revival of the musical that was opened originally with Bernedette Peters in the role. McEntire was an instant sensation, performing the role on Broadway for eighteen months. In many ways this role made her, as it showed she could do far more than sing, and was in fact a very skilled comedic actor.

This clip, shot by an audience member, does a remarkable job of capturing part of one of those performances.

Hat tip Diane Zimmerman.

5 comments

Iraq recaptures Mosul mosque from ISIS

10:47 pm

Iraqi troops have recaptured the Mosul mosque where ISIS declared its caliphate three years ago.

After eight months of grinding urban warfare, Iraqi government troops on Thursday captured the ruined mosque at the heart of Islamic State’s de facto capital Mosul, and the prime minister declared the group’s self-styled caliphate at an end. Iraqi authorities expect the long battle for Mosul to end in coming days as remaining Islamic State fighters are bottled up in just a handful of neighborhoods of the Old City.

The seizure of the nearly 850-year-old Grand al-Nuri Mosque — from where Islamic State proclaimed the caliphate nearly three years ago to the day — is a huge symbolic victory. “The return of al-Nuri Mosque and al-Hadba minaret to the fold of the nation marks the end of the Daesh state of falsehood,” Prime Minister Haider al-Abadi said in a statement, referring to the hardline Sunni Mulsim group by an Arabic acronym.

The fall of Mosul would in effect mark the end of the Iraqi half of the IS caliphate, although the group still controls territory west and south of the city, ruling over hundreds of thousands of people.

Its stronghold in Syria, Raqqa, is also close to falling.

This defeat of ISIS by Iraqi government forces has been building for months as they have been pushing steadily but slowly forward in heavy street fighting in Mosul. The victory is even more significant in that it has been achieved by Iraq, not American forces, though they have been happily allied with us, and have gladly taken our aid.

Will this victory lessen Islamic radicalism worldwide? No, not likely. The last eight years of bad foreign policy has allowed this evil to fester. It will take a lot more than just the fall of ISIS to cleanse the wound. We still have the Iran government and numerous terrorists organizations running governments throughout the Middle East that are their allies. They are not going away, and their goal of destroying the infidel remains.

22 comments

Surrey Satellite closing U.S. factory

5:10 pm

Capitalism in space: Surrey Satellite Technology, one of the first companies to build smallsats and cubesats, is closing its U.S. factory in Colorado and concentrating its satellite work once again in the UK.

It appears the company might have gotten a little fat and lazy, and has allowed the competition to begin passing it by:

Parker said the exact number of people SST-US will let go has not been determined. SSTL’s decision to layoff workers in the U.S. is not related to the decline in geostationary telecommunications satellite orders that triggered a reduction in workers at Space Systems Loral, Parker said. The majority of SSTL’s business is in remote sensing, navigation and science — spacecraft typically found in non-geosynchronous orbits.

Instead, Parker said it was more out of concern that the smallsat movement the company had championed for years had picked up steam and was moving without SSTL. “We had grown slightly fatter, slightly more complacent, so we are doing a lot of work on our organization. We started last year and changed our organizational structure internally. We changed the way our teams are organized so we now have a much flatter structure with more autonomy,” she said.

SSTL is not reducing its headcount in the U.K., Parker said.

This kind of reminds me of ULA’s recent effort to streamline its operations, faced with competition from SpaceX. Here, Surrey is finding itself getting beat by a lot of new players, and had found it needs to reshape itself to survive.

2 comments

As predicted climate scientists begin adjusting satellite data to fit models

12:37 pm

If the facts don’t fit the theory, change the facts! The scientists in charge of the climate satellite data produced by Remote Sensing Services (RSS) in California have decided to adjust their satellite data to increase the warming trend since 2000 and make that data more closely match the surface temperature data that NASA and NOAA have already altered to show that same warming trend.

Researchers from Remote Sensing Systems (RSS), based in California, have released a substantially revised version of their lower tropospheric temperature record. After correcting for problems caused by the decaying orbit of satellites, as well as other factors, they have produced a new record showing 36% faster warming since 1979 and nearly 140% faster (i.e. 2.4 times larger) warming since 1998. This is in comparison to the previous version 3 of the lower tropospheric temperature (TLT) data published in 2009.

How have they done this? They made several changes, the first two of which appear quite questionable. First, they addressed the “time of observation issue.” There is a belief among some climate scientists that the time temperature readings were taken can introduce an error in the long term trends.

To account for changes in observation times, the RSS group used a number of different approaches and models to try and estimate what the temperature would have been if the measurement time remained constant. This involves a combination of satellite observations (when different satellites captured temperatures in both morning and evening), the use of climate models to estimate how temperatures change in the atmosphere over the course of the day, and using reanalysis data that incorporates readings from surface observations, weather balloons and other instruments.

Depending on the time of the observation correction approach chosen, the resulting temperature trends between 1979 and 2016 ranged from as low as 0.13C per decade to as high as 0.22C per decade. The RSS group ultimately decided that the most reasonable set of parameters give a temperature trend of 0.17C. [emphasis mine]

I am puzzled by this, since satellites in orbit do not take readings at one particular time, but at a wide range of times. In fact, I would say that the number of readings, at all different times, would easily introduce enough randomness into the results that any error would be insignificant. Instead, these scientists have decided to adjust the raw data to add a warming trend of almost a tenth of a degree centigrade.

Next, they simply decided that the data coming from some satellites should be excluded.
» Read more

10 comments
1 … 594 595 596 597 598 … 1,142