Last week, astronomers announced that they had made a giant breakthrough by
finding something small. They turned up a planet that happens to be the most diminutive ever discovered beyond our own solar system, at least around a common type of star. The object is roughly twice Earth's girth, which, as planets go, is decidedly petite.
Although this newly discovered runty world is, in the grand matrix of the cosmos, probably nothing special, it's possible that it heralds wonderful things. This remote rock could be akin to the flotsam and jetsam Columbus saw just before the New World hove into view. It might be the harbinger of a major discovery.
What do we know about this fresh find? First off, it belongs to a red dwarf star with the pedestrian name Gliese 876, a sun that's only about one-third as hefty as our own. The planet speeds around this pint-size star every two days in an orbit that's barely larger than a loose-
fitting belt -- only one-tenth the size of Mercury's path around the Sun. Despite the fact that red dwarfs are relatively cool, the small orbit means that temperatures on this world are extra toasty -- several hundred degrees Celsius. In other words, this planet is unlikely to have any inhabitants. It's just too hot.
OK, then why get excited by the rooting up of a small world around a small star? The reason derives from our changing view of these bantam suns and their suitability for hosting planets where life could arise.
A new look at small stars
A few years ago, red dwarfs were thought to be the stellar hoarstones of barren real estate. Inevitably barren. Everyone knew their dull glow could only warm planets that happened to orbit close by. However, such star-hugging worlds would quickly be locked into a kind of static embrace, with one hemisphere always staring at the star, much in the way one hemisphere of the moon always faces Earth.
It was assumed that these worlds would become savagely hot on one side, and desperately cold on the other,
destroying their atmosphere together with any chances for life. Researchers hunting for radio signals from alien societies didn't bother to aim their antennas in the direction of red dwarfs.
Times change. More recent realistic analysis of what would happen to a planet that closely circles a red dwarf has shown that its atmosphere would quickly spread the heat.
Greg Laughlin, an astronomer at the University of California at Santa Cruz who was part of the Gliese 876 discovery team, notes that "Even Venus, a local planet that only slowly turns on its axis, has pretty much the same temperatures all the way around." That's because Venus has an atmosphere.
So the paradigm has shifted, as the geeks like to say, and places we once thought were flat-out uninhabitable are now possible abodes for life. Red dwarfs are no longer regarded as hopeless cosmic desert.
This is revolutionary because red dwarfs are the most plentiful stars in the universe. For every sun-like star, there are eight red dwarfs. If red dwarfs commonly have planets -- a possibility given impetus by the discovery of the world around Gliese 876 -- and if some of these worlds orbit at slightly greater, and therefore cooler, distances from their home star, then habitable worlds could be as abundant as summer mosquitoes. Most of the life in the universe could bask in the ruddy light of red dwarfs.
This leads to a startling possibility, because red dwarfs have a characteristic that distinguishes them from stars like the sun: longevity. Small stars, like small dogs, live longer. Our own sun has been boiling away for nearly 5 billion years; it has another 5 billion to go before it starts to shudder and die.
But a red dwarf would offer much more time for development, 100 billion years or more, because these dim bulbs are parsimonious with their fuel.
Ancient civilizations?
If life, and occasionally intelligent life, exists elsewhere, then the most ancient civilizations are surely encamped around the oldest stars; and the oldest that still shine are red dwarfs. Of course, 14 billion years after the big bang, even the most aged of red dwarfs are still teenagers. But if some have planets on which biology bloomed early, that life has a history that is two or three times as long as the span between Earth's earliest microorganisms and the ascent of man.
Such an ancient society, with far more time to exploit science, might easily be able to betray its existence. No, we haven't found evidence for such civilizations yet, but if we do, it's conceivable that they developed on a world of which the rock found around Gliese 876 is merely a first example. That overheated planet might be the first signpost of myriad worlds where life could flourish.
May 18 to May 24 Pastor Yang Hsu’s (楊煦) congregation was shocked upon seeing the land he chose to build his orphanage. It was surrounded by mountains on three sides, and the only way to access it was to cross a river by foot. The soil was poor due to runoff, and large rocks strewn across the plot prevented much from growing. In addition, there was no running water or electricity. But it was all Yang could afford. He and his Indigenous Atayal wife Lin Feng-ying (林鳳英) had already been caring for 24 orphans in their home, and they were in
On May 2, Chinese Nationalist Party (KMT) Chairman Eric Chu (朱立倫), at a meeting in support of Taipei city councilors at party headquarters, compared President William Lai (賴清德) to Hitler. Chu claimed that unlike any other democracy worldwide in history, no other leader was rooting out opposing parties like Lai and the Democratic Progressive Party (DPP). That his statements are wildly inaccurate was not the point. It was a rallying cry, not a history lesson. This was intentional to provoke the international diplomatic community into a response, which was promptly provided. Both the German and Israeli offices issued statements on Facebook
President William Lai (賴清德) yesterday delivered an address marking the first anniversary of his presidency. In the speech, Lai affirmed Taiwan’s global role in technology, trade and security. He announced economic and national security initiatives, and emphasized democratic values and cross-party cooperation. The following is the full text of his speech: Yesterday, outside of Beida Elementary School in New Taipei City’s Sanxia District (三峽), there was a major traffic accident that, sadly, claimed several lives and resulted in multiple injuries. The Executive Yuan immediately formed a task force, and last night I personally visited the victims in hospital. Central government agencies and the
Australia’s ABC last week published a piece on the recall campaign. The article emphasized the divisions in Taiwanese society and blamed the recall for worsening them. It quotes a supporter of the Taiwan People’s Party (TPP) as saying “I’m 43 years old, born and raised here, and I’ve never seen the country this divided in my entire life.” Apparently, as an adult, she slept through the post-election violence in 2000 and 2004 by the Chinese Nationalist Party (KMT), the veiled coup threats by the military when Chen Shui-bian (陳水扁) became president, the 2006 Red Shirt protests against him ginned up by
RSS