Month: July 2019

Enlarge / Buzz Aldrin wants NASA to go somewhere. (credit: Hubert Vestil/Getty Images)

Just after Memorial Day this year, I began talking regularly with the pilot of the first spacecraft to land on the Moon. We had spoken before, but this was different—it seemed urgent. Every week or two, Buzz Aldrin would call to discuss his frustration with the state of NASA and his concerns about the looming 50th anniversary of the Apollo 11 Moon landing without a lack of discernible progress to get back.

Even at 89, Aldrin remains remarkably engaged in the aerospace community, often showing up to meetings and conferences unannounced. Aldrin asks questions. He talks to the principals. In the last two years, the aerospace legend has been to the White House for major space announcements by President Trump, served as an adviser to the National Space Council, and supported the White House goal of returning to the Moon by 2024.

But what NASA has been doing to get back there, for the better part of two decades, just hasn’t been working. President Bush directed NASA back to the Moon more than 15 years ago, and in one form or another, NASA has been spending billions of dollars each year to build a big, heavy spacecraft and a bigger, much heavier rocket as the foundation for such a return. Along the way, NASA has enriched a half-dozen large aerospace contractors and kept Congress happy. But the space agency still can’t even launch its own astronauts into low-Earth orbit, let alone deep space or the Moon.

Enlarge / A depiction of one of the trio of satellites that will form the Laser Interferometer Space Antenna. (credit: NASA)

The first detection of gravitational waves came via an instrument that has to strain to overcome the constant background of vibrations and jolts that occur on Earth. Its success has helped push for the pursuit of a project that would rise above all that noise. LISA—the Laser Interferometer Space Antenna—would detect gravitational waves using the same technique as LIGO but place its hardware in space, free of any ground-based vibrations. Preliminary tests of prototype hardware has found that the idea should work.

LISA isn't expected to be put in place until the 2030s, but that hasn't stopped astronomers and physicists from contemplating the things that it might possibly detect. Two of these astronomers, Nicola Tamanini and Camilla Danielski, are now suggesting that LISA could be used to identify a very strange class of planets: heavy planets orbiting binary pairs of white dwarf stars. But because of its exquisite sensitivity, LISA could potentially spot them orbiting outside our own galaxy.

How would this work?

Gravitational waves are produced when any two objects with mass interact, but they're too tiny to be detected unless the objects in question are both massive and near to each other. The LIGO detector is sensitive enough to pick up things like neutron stars and black holes, all of which are both incredibly dense and have masses on the order of the Sun's and larger. But—due to its enhanced sensitivity and the frequencies of gravitational waves that it will be sensitive to—LISA will be able to pick up objects that are dense but not as massive.