In Space, No One Can Hear You Scheme

Play the pipes slowly for Atlantis, Endeavor, and Discovery.  In 2010, NASA will retire its old workhorses for good.

The shuttering of the shuttle program leaves American space exploration in an awkward situation.  The next generation of spacecraft, dubbed the Constellation Project, will not be operable until at least 2015.  For the intervening five years, the U.S. space program must rely on Russia to ferry its astronauts to the International Space Station.

The ISS

The International Space Station (image: NASA.gov)

NASA has used Soyuz capsules to transport astronauts and parts since the ISS first sailed into orbit in 1998.  Despite the ease of scientific cooperation, the deal has always been a political tightrope walk.  The Iran-North Korea-Syria Non-Proliferation Act, a 2000 resolution, would have prohibited NASA from dealing with Russia, which often sells military technology to Iran.  A little bit of legislative acrobatics resulted in a waiver that allowed NASA to rent out seats on Russian spacecraft.

A renewal of the INKSNA waiver, scheduled for this year, seemed to be a given.  Without access to Soyuz capsules, the U.S. would have no means of carrying its own crew, or rescuing them from the space station if something should go awry.  Should the waiver fail to be renewed in time, NASA would most likely withdraw its presence from the ISS.

Then came the August 2008 invasion of the former Soviet republic of Georgia.  Furious hawks in the U.S. government, including Republican presidential candidate John McCain, called for sanctions and penalties against Russia.  The move to renew the INKSA waiver stalled.

Ironically, it was Democratic Senator Barack Obama, who is considered unenthusiastic about funding human space exploration, who stepped in.  He wrote to his colleagues, urging them to prioritize allowing the U.S. access to the International Space Station.  On September 24, it passed easily, garnering Obama a letter of thanks from the administrator of NASA, Michael Griffin, who concluded by saying that “without your leadership, this would not have happened”.  Griffin, a Republican appointee, would usually have little cause to praise a Democratic candidate for president.  But science is often a sphere in which cooperation trumps political grudges.

It began on July 17th, 1975. On that date, 200 kilometers above the city of Metz, France, an American astronaut and a Russian cosmonaut shook hands.

nasa.gov)

Leonov and Stafford bridge the divide. (Image source: nasa.gov)

Thomas P. Stafford and Alexei Leonov were the commanders of American and Russian spacecraft in the Apollo-Soyuz Test Project, the first joint spaceflight undertaken by the two countries.  During the nine-day mission, the two modules performed several scientific missions, including experiments in photographing solar eclipses.  Apollo-Soyuz had another goal in mind: détente. The meeting between American and Soviet astronauts signaled that Cold War tensions were thawing.

Space hadn’t always been this friendly.

A decade earlier, President Kennedy had remarked that America’s competition with the Soviet Union for supremacy in space was a challenge “that we are willing to accept, one we are unwilling to postpone, and one which we intend to win.”

“It was like boys in a locker room bragging,” said Professor Igor Lukes, a professor of International Relations at Boston University.  “Just another substitute for international competition: to see who could put more and more people up there.”

Sputnik, the plucky satellite that sparked a space race. (Image source: nasa.gov)

The launch of the Soviet satellite Sputnik in 1957 sparked an effort by the two superpowers to outdo each other in displaying technological supremacy, culminating in the American moon landing of 1969.  While both powers staked claims of “winning” the space race, by the mid-seventies the zeal for competition had cooled, on earth as well as above it.

After Apollo-Soyuz, other collaborations followed.  The Shuttle-Mir missions, conducted from 1994 to 1998, flew American astronauts to the Mir space station to perform experiments and engage in cultural exchange.  NASA also used Shuttle-Mir to gather data on the physiological and psychological effects of long-term spaceflight.  During this period, both agencies talked of undertaking another, more ambitious joint venture: the construction of an international space station.

On November 20, 1998, the first element of the station, the Zarya Functional Cargo Block, blasted into space on the back of a Russian Proton rocket.  The latest addition is a Japanese experimental laboratory nicknamed Kibo, attached in May of 2008.  The ISS is the size of a football field and can be seen with the naked eye from earth.  Fifteen countries from across the world have a stake in seeing it stay afloat.

There is still potential for politics to disrupt the peace.  Alexandros Petersen, an analyst at the Center for Strategic Intelligence Studies, warns against relying too much on the volatile superpower that Russia has become.

“Even though there is little that Moscow would gain from shifting away from space cooperation, it would serve the function of showing the Russian people that Moscow can deny Washington’s access to space.”
He advocates exploring other options, including collaborating with European or Japanese space agencies to quickly develop alternative means of transporting astronauts to the ISS, to ensure the space station’s future does not hinge upon the US maintaining a friendly relationship with Russia.

Petersen’s words of caution will not go unheard.  President Bush signed the NASA Reauthorization Act on October 16, which stipulates that the American space agency determine “the impact of a Space Shuttle flight program extension on the United States’ dependence on Russia for International Space Station crew rescue services”.  The U.S. government, while maintaining relatively cordial relations with Russia, still hedges its bets.

Still, the two countries find common ground in space.  Despite the occasional bump in the road, it seems that the heavenly honeymoon will continue, still strong after ten years and two billion kilometers traveled.

It Came From the Center of the Galaxy!

University of Chicago

source:University of Chicago

Deep in the heart of the Milky Way lurks an ever-hungry force, consuming planets, stars, and nebulae with voracious appetite. The monster in question is Sagittarius A*, thought to be the location of a massive black hole. Its 25,000 light year distance from Earth and relatively tiny size make SgrA* difficult to observe. A recent study led by MIT astronomer Sheperd Doeleman, published in the Sept. 4 issue of Nature, offers the closest look yet.

Doeleman’s project made use of Very Long Baseline Interferometry, or VLBI. This technique uses multiple telescopes distributed across the planet, which is like using a telescope equal in size to the distance between them. The researchers sought to maximize resolving power by linking telescopes from California, Arizona, and Hawaii, and measuring wavelengths of 1.3mm, the smallest ever attempted. This allowed the scientists to map the size of SgrA* to 37 microarcseconds. To give some idea of the scale, Doeleman said, “it’s like seeing a baseball on the moon with the naked eye.”

But how were the telescopes able to see something from which even light cannot escape? Scientists measured radio, infrared, and x-ray emissions from SgrA*, but these do not originate from the black hole itself. As Alan Marscher, professor of astronomy at Boston University, describes, matter drawn towards the event horizon, the outer limit of the black hole, doesn’t just fall straight in- it spins around like water circling a drain. As it rotates, it loses energy in the form of radiation, which can be picked up by the telescope array.

Mapping SgrA* has bolstered the case for identifying the object at the galactic center as a black hole, given its extremely small size and its extremely large mass of four million solar masses. No other phenomenon is known to have such a high density. There is, Doeleman said, a slight chance that SgrA* could be a more exotic construct known as a Boson star, which is composed of unique particles that exist much closer to each other than in normal stars. The Boson star, however, is only a theoretical possibility, and has yet to be observed.

Furthermore, scientific principles rule out the possibility that SgrA* is an aggregate of matter. According to the laws of physics, “any object that was originally at the center of the galaxy, whether it was a planet, some gravel, or a collection of Hello Kitty dolls, would have collapsed into a black hole after at least 500 years”, said Doeleman.

Future studies will attempt to push the resolving power even further, with telescopes placed even further apart and measuring even smaller wavelengths. Doeleman hopes to eventually make use of the newly constructed ALMA array, a collection of 50 dishes located in Chile. The addition of more telescopes will ultimately allow scientists to construct a real image of a black hole, rather than a mathematical representation.

Still, Marscher mused, there is a point beyond which even the most powerful telescope cannot see. Little is known about the character of what lies beyond the event horizon, he said, and at this point we lack the capability to describe it. “The universe,” he said, “conceals a lot from us.”

Original Article: Doeleman et al.  “Event-horizon-scale structure in the supermassive black hole candidate at the Galactic Centre”.  Nature 455:78-80 (4 September 2008).