What is the Smallest Star?

The biggest stars in the Universe are the monster red hypergiants, measuring up to 1,500 times the size of the Sun. But what are the smallest stars in the Universe? (from universetoday.com)

The smallest stars around are the tiny red dwarfs. These are stars with 50% the mass of the Sun and smaller. In fact, the least massive red dwarf has 7.5% the mass of the Sun. Even at this smallest size, a star has the temperature and pressures in its core so that nuclear fusion reactions can take place.
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One example of red dwarf star is the closest star to Earth, Proxima Centauri, located just 4.2 light-years away. Proxima Centauri has 12% the mass of the Sun, and it’s estimated to be just 14.5% the size of the Sun. The diameter of Proxima Centauri is about 200,000 km. Just for comparison, the diameter of Jupiter is 143,000 km, so Proxima Centauri is only a little larger than Jupiter.

But that’s not the smallest star ever discovered.

The smallest known star right now is OGLE-TR-122b, a red dwarf star that’s part of a binary stellar system. This red dwarf the smallest star to ever have its radius accurately measured; 0.12 solar radii. This works out to be 167,000 km. That’s only 20% larger than Jupiter. You might be surprised to know that OGLE-TR-122b has 100 times the mass of Jupiter, but it’s only a little larger.

And that is the smallest known star. But there are certainly smaller stars out there. The smallest theoretical mass for a star to support nuclear fusion is 0.07 or 0.08 solar masses, so smaller stars are out there.

Noted Women’s Rights Activist in Congo Eludes Group of Gunmen

A leading human rights activist from the Democratic Republic of Congo said on Friday that he had narrowly escaped what appeared to be an assassination attempt when gunmen infiltrated his home, took his children hostage and killed a security guard in a spray of bullets before fleeing in the family car. (from nytimes.com)

On Thursday evening, four or five unidentified gunmen entered the home of the activist, Dr. Denis Mukwege, 57, while he was out, forced his two daughters and their friend onto the floor, confiscated their telephones and threatened to shoot them if they made any noise, according to a statement from Physicians for Human Rights, a humanitarian organization based in the United States, and a neighbor.Dr. Mukwege, one of Congo’s most high-profile personalities and a past Nobel Peace Prize nominee, said in a telephone interview on Friday that when he pulled up to the gate at his home in Bukavu, in eastern Congo, about an hour later, he saw “very strange people.” The gunmen forced their way into his car, and one stepped out and trained his gun on the doctor. Then one of his security guards appeared out of nowhere. The gunman menacing Dr. Mukwege whirled around and opened fire on the guard instead, Dr. Mukwege said, then fired at him. “They were shooting bullets in my direction,” he said. He scrambled to get away, and the assailants ran out of ammunition without hitting him. “And then they just jumped again in the car.”

The three children were also unharmed, but Dr. Mukwege’s security guard — Papa Djef, as he was known to the family — was killed. “He was like my child,” Dr. Mukwege said. “He was really a brave man. He just paid his life to save mine.”

The Loongson Low Power MIPS Processesor

Loongson is a general purpose RISC processor. It is a 64-bit MIPS compatible processor, which is patented by MIPS Technologies. The silicon is designed by ICT/CAS China and manufactured by ST Microelectronics. The online retail price for Loongson-2F chip is about USD30~40, which is available from the Lemote’s online shop. Of course, you can order it in the name of STLS2F from ST as well.
(from dev.emcelettronica.com)

Loongson-2F, the latest version operates at 1.2 to 1.5GHz and only consumes 5 watts. Additionally, Loongson-2F also supports DDR2 and USB2.0. As a RISC processor, Loongson processor is struggling on its way to the market for a long time. As we know, the processor market is highly competitive. ARM has been a de facto standard RISC processor IP in mobile terminals and embedded SoC. MIPS is not the market leader. It is mainly used in digital video and telecommunication segments like STB, HDTV, IPTV, DSL modem, laser print and video game consoles (Sony PS/PSP). MIPS processors are usually available in IP and embedded SoC, you can find some old types available for legacy SGI workstation, Windows CE PPC and HPC. AMD acquired Alchemy MIPS processor in PMP and HDTV, and finally it got rid of this business line before long. Sometimes, I wonder why AMD bought Alchemy at the very beginning.

Although it is hard to find the market opportunities for MIPS. ICT offers a series of open source MIPS based designs for NAS, Linux desktop PC, thin client terminal and others with their own Loongson processor family. Recently, they start to promote the MIPS Netbook to the consumer market. The price is comparable to the ATOM/Nano based Netbook, many local Linux developers enjoy it very much. Because it is very hard to buy a high speed MIPS board with low price. Can you find a 300USD evaluation board for 1.5GHz MIPS processor? The system has been installed with Debian MIPS distribution and native GCC for MIPS. Compare to an ordinary x86 Netbook, the user experience is same. MIPS still have major OS support from Windows CE and Linux. Most of the popular software components are available on these platforms. Netbook and MID are great chances for MIPS to return to the desktop/mobile computing market. However, I can name many limitations for MIPS: you can not play Real Video and QuickTime, you can not run WINE, you can not use commercial DLLs for x86 and Windows, and you may face to the driver issues. The MIPS Netbook only fits the requirements for the highly experienced communities or the people who have no PC experiences at all (like my parents) and just want to check their emails or browsing. The MIPS device is good for them because it is totally virus-free.

I don’t want to promote MIPS IP or Loongson Netbook here. I also don’t think MIPS Netbook can win the market. Non-x86 structure can not beat x86 in Netbook, because people consider Netbook a low-cost laptop PC. However MIPS should focus its advantage on digital video segments, including media adapter, PMP and PND. And so we, as the engineers, let us check the specification and find out its opportunities.

– MIPS-III 64 bit superscalar architecture
– 900 MHz clock frequency
– Single/double precision floating point units
– New streaming multimedia instruction set support (SIMD)
– 64 KB I-cache, 64KB D-cache, on-chip 512 KB unified L2 cache
– On chip DDR2 667 and PCI-X controller
– 4W@900MHz power consumption:
– Voltage/frequency scaling
– Standby mode support
– L2 cache disable/enable option
– 90 nm process technology
– JTAG interface

Apparently, this chip has advantage on 64-bit performance, FPU, SIMD over mainstream ARM products. Meanwhile it has much lower power consumption over x86 processor. It requires 3rd party north/south bridges (VIA) to complete the system design. A Chinese company HiSand also developed a Loongson-1 based SoC for Internet Radio, digital photo frame and other consumer products. Its HS3210 has integrated a lot of peripherals on-chip with a 266MHz MIPS core. It is the first step of the right direction. Only if its MIPS SoC wins the market, the Loongson can live on. I have no doubt about the market capacity of consumer electronics, if HS3210 has good quality with low price as they claimed, it is make sense to buy a Loongson computer/Netbook for development purpose with the native toolchains. Loongson also offers a simulator so you can evaluate the system.

Reference

Loongson – Wikipedia

http://en.wikipedia.org/wiki/Loongson

Loongson Official Site, in Chinese
http://www.loongson.cn/

A French company EMTEC released its Loongson based subnotebook under the brand name Gdium. The Mandriva G Linux is pre-installed in a USB key. It is available in Europe, China and US.
http://www.gdium.com/

The Chinese manufacturer Lemote offers new 8.9″ Netbook, running Debian GUN/Linux, available in Europe at the Dutch company Tekmote Electronics.
http://www.lemote.com/english/index.html

Datasheet of 2F from ST Electronics
Datasheet ST
http://www.st.com/stonline/products/literature/ds/14793/stls2f02.pdf

HiSand IC Design Inc,.
http://www.hisand.cn/

Hurricane Sandy pounded the Bahamas

Hurricane Sandy raged through the Bahamas early Friday after leaving 21 people dead across the Caribbean, following a path that could see it blend with a winter storm and reach the U.S. East Coast as a super-storm next week. (from yahoo.com)

Sandy knocked out power, flooded roads and cut off islands in the storm-hardened Bahamas as it swirled past Cat Island and Eleuthera, but authorities reported no deaths in the scattered archipelago.

“Generally people are realizing it is serious,” said Caroline Turnquest, head of the Red Cross in the Bahamas, who said 20 shelters were opened on the main island of New Providence.

Sandy, which weakened to a category 1 hurricane Thursday night, caused havoc in Cuba early in the day, killing 11 people in eastern Santiago and Guantanamo provinces as its howling winds and rain toppled houses and ripped off roofs. Authorities said it was Cuba’s deadliest storm since July 2005, when category 5 Hurricane Dennis killed 16 people and caused $2.4 billion in damage.
Sandy also killed one person while crossing Jamaica on Wednesday and 10 in Haiti, where heavy rains from the storm’s outer bands caused flooding in the impoverished and deforested country.

Early Friday, the hurricane’s center was about 145 miles (235 kilometers) east-southeast of Freeport, Bahamas. The storm had maximum sustained winds of 85 mph (140 kph) and was moving north-northwest at 13 mph (20 kph). Forecasters warned that Sandy will likely mix with a winter storm to create a monster storm in the eastern U.S. next week whose effects will be felt along the entire Atlantic Coast from Florida to Maine and inland to Ohio.

Sandy, which crossed Cuba and reached the Bahamas as a category 2 hurricane, was expected to maintain its category 1 storm status for the next few days.

In the Bahamas, power was out on Acklins Island and most roads there were flooded, government administrator Berkeley Williams said.
On Ragged Island in the southern Bahamas, the lone school was flooded. “We have holes in roofs, lost shingles and power lines are down,” said Charlene Bain, local Red Cross president. “But nobody lost a life, that’s the important thing.”

Steven Russell, an emergency management official in Nassau, said docks on the western side of Great Inagua island had been destroyed and the roof of a government building was partially ripped off.

Sooner Halvorson, a 36-year-old hotel owner from Colorado who recently moved to the Bahamas, said she and her husband, Matt, expected to ride out the storm with their two young children, three cats, two dogs and a goat at their Cat Island resort.

In an announcement at the end of Cuba’s Thursday night newscast, Cuban authorities said the island’s 11 dead included a 4-month-old boy who was crushed when his home collapsed and an 84-year-old man in Santiago province.
Santiago, Cuba’s second largest city near the eastern tip of the island, was spared the worst of the storm, which also slammed the provinces of Granma, Holguin and Las Tunas.

In Haiti, Joseph Edgard Celestin, a spokesman for the civil protection office, said the country’s death toll stood at nine, including three people who died while trying to cross storm-swollen rivers in southwestern Haiti. He did not provide specifics of how other people died.
Officials reported flooding across Haiti, where many of the 370,000 people still displaced by the devastating 2010 earthquake scrambled for shelter. More than 1,000 people were evacuated from 11 quake settlements, according to the International Organization for Migration.

With storm conditions projected to hit New Jersey with tropical storm-force winds Tuesday, there was a 90 percent chance that most of the U.S. East Coast would get steady gale-force winds, flooding, heavy rain and maybe snow starting Sunday and stretching past Wednesday, U.S. forecaster Jim Cisco said.
There were no reports of injuries at the U.S. naval base at Guantanamo Bay in Cuba, but there were downed trees and power lines, said Kelly Wirfel, a base spokeswoman. Officials canceled a military tribunal session scheduled for Thursday for the prisoner charged in the 2000 attack on the Navy destroyer USS Cole.

Weather trackers say the hardest-hit areas could span anywhere from the coastal Carolinas up to Maine, with New York City and the Boston area potentially in harm’s way.

NASA Statement On Alpha Centauri Planet Discovery

WASHINGTON — The following is a statement about the European Southern Observatory’s latest exoplanet discovery from NASA’s Science Mission Directorate Associate Administrator, Dr. John Grunsfeld. (from nasa.gov release : 12-366)

“We congratulate the European Southern Observatory team for making this exciting new exoplanet discovery. For astronomers, the search for exoplanets helps us understand our place in the universe and determine whether Earth is unique in supporting life or if it is just one member of a large community of habitable worlds. NASA has several current and future missions that will continue in this search.

An example [sic] is NASA’s Kepler mission. It was specifically designed to survey a specific region of our Milky Way galaxy to detect Earth-size and smaller planets in or near the habitable zone — that region around a star where it is theoretically possible for a planet to maintain liquid water on its surface — and determine the fraction of the hundreds of billions of stars in our galaxy that might have such planets. Kepler works very differently from HARPS. Rather than detecting the wobble in the host star, Kepler detects the slight dimming of a star when a planet passes in front of it.

NASA’s Hubble and Spitzer space telescopes have contributed to the study of exoplanets. Using their photometric and spectroscopic sensitivity, these space telescopes have made the first steps in characterizing the atmospheres of planets around other stars. They can only do this when the exoplanets pass serendipitously in front of its star, allowing the space telescope to study light that has filtered through the planet’s atmosphere.

NASA’s James Webb Space Telescope (JWST) will provide a unique facility that will serve through the next decade as the mainstay for characterization of transiting exoplanets. The main transit studies JWST will be able to undertake are: discovery of unseen planets, determining exoplanet properties like mass, radius, and physical structure, and characterizing exoplanet atmospheres to determine things like their temperature and weather. If there are other planets in the Alpha Centauri system farther from the star, JWST may be able to detect them as well through imaging.

NASA is also studying two medium-class exoplanet missions in our Explorer program, and in the spring of 2013 will select one of them to enter development for flight later in the decade.”

(editor’s note: faster engines are needed, init? )

Clinton Forbids Funding of Human Clone Studies (05.03.1997)

Warning against the temptation “to play God,” President Clinton yesterday banned federal funding of human cloning research and asked privately funded scientists to halt such work until a national bioethics commission reviews what he called the “troubling” legal and ethical implications.

By Rick Weiss
Washington Post Staff Writer
Wednesday, March 5, 1997; Page A10

“Each human life is unique, born of a miracle that reaches beyond laboratory science,” Clinton said during a brief ceremony in the Oval Office, where he announced his executive directive. “I believe we must respect this profound gift and resist the temptation to replicate ourselves.”

The president’s order, effective immediately, comes 10 days after Scottish scientists reported they had cloned a sheep named Dolly from adult cells and two days after researchers in Oregon revealed they had bred a pair of rhesus monkeys from cloned embryo cells.

In 1994, Clinton signed an executive order banning federal funding of certain kinds of research involving human embryos, and Congress has prohibited other kinds of human embryo research. However, said Clinton yesterday, “after reviewing these restrictions, our administration believes that there are loopholes that could allow the cloning of human beings if the technology were developed.”

The president acknowledged that much of the cloning-related research in this country is conducted by private companies not covered by the federal ban. Some biotechnology companies are trying to clone pigs with humanized organs for transplantation into people, for example, and other companies have cloned goats that make human medicines in their milk. Clinton said he supported continued research in animals, but he asked companies to impose upon themselves a “voluntary moratorium” on expanding that work to humans.

“Any discovery that touches upon human creation is not simply a matter of scientific inquiry. It is a matter of morality and spirituality as well,” Clinton said. “That is why I am urging the entire scientific community — every foundation, every university, every industry that supports work in this area — to heed the federal government’s example.”

Highlighting the ban’s importance, Clinton made the announcement flanked by Vice President Gore, Health and Human Services Secretary Donna E. Shalala, National Institutes of Health Director Harold E. Varmus, presidential science adviser Jack Gibbons and Princeton President Harold T. Shapiro, who chairs the National Bioethics Advisory Commission. That commission is scheduled to meet at the Watergate Hotel on March 13 and 14 to discuss the ethics of human cloning and has been asked by the president to submit a final report on the issue by the end of May.

Many scientists, including those involved in cloning research, have insisted repeatedly during the past week that they have no interest in cloning humans, even if it were technically possible. After hearing of the president’s ban, several reiterated those feelings.

“The president’s reaction is a prudent one and is fully appropriate, and speaking for the industry, we support him wholeheartedly,” said Carl B. Feldbaum, president of the Biotechnology Industry Organization, which represents 700 biotechnology companies and institutions.

Feldbaum said it was understandable that Clinton, and probably much of the public, felt a need to put the brakes on the quickly evolving scientific field. “You go from cloning of sheep a week ago and you cloned monkeys this week and you figure humans have got to be cloned by next week,” he said.

Feldbaum said he was heartened, however, to see Varmus by Clinton’s side in the Oval Office — an arrangement he said indicated Clinton’s ongoing support for basic research on embryos, which could lead to improved treatments for infertility and other medical problems.

Colin Stewart, a researcher at the National Cancer Institute’s research center in Frederick, Md., said he too was encouraged by Clinton’s apparent effort not to reject all genetics research as he placed limits on human cloning.

“What I’ve been encouraged by in all this has been the level of debate and the high level of consciousness of what’s going on,” Stewart said, “and I hope this won’t stymie debate about long-term policy on human embryos and other forms of mammalian research.”

Rep. Constance A. Morella (R-Md.), whose district includes the NIH, has called for the first congressional hearings on cloning, to be held this afternoon in the Rayburn House Office Building. Scheduled speakers include Varmus, Case Western Reserve University bioethicist Thomas H. Murray; M. Susan Smith, director of the Oregon research center where the monkeys were cloned; and James Geraghty, president of Genzyme Transgenics, a Massachusetts company that has produced goats from cloned embryos.

Sen. Bill Frist (R-Tenn.) announced yesterday that his hearings on cloning, scheduled for next Wednesday in the Dirksen Senate Building, will include testimony from Ian Wilmut, the Scottish researcher who oversaw the cloning of Dolly.