DSCOVR Satellite, SETI is Calling, and Binary Stars are Born

“GoreSat” Looks Both Ways

After two false-starts, SpaceX finally launched its NOAA payload, the Deep Space Climate Observatory (DSCOVR), which will eventually keep station at the L-1 libration point 1.5 million kilometers (930,000 miles) from Earth, where it can observe both Earth and the Sun. It will take nearly four months to reach L-1, where the gravitational pulls of Earth and the Sun are equal, allowing a spacecraft at that location to orbit the Sun at exactly the same rate as Earth. In the case of DISCOVR, the satellite will thus be able to maintain a position between Earth and the Sun and observe both continuously during its two-year long mission.

DSCOVR will monitor spaceweather, which is the effect of solar activity (such as solar wind, solar flares, and coronal mass ejections) on the space environment – and particularly on Earth. Its strategic position, about a million miles closer to the Sun than Earth, will allow it to alert ground controllers to any spaceweather phenomena about an hour before the effects are felt on our planet. This “early warning” may allow systems operators to respond better to incoming solar storms that can have damaging effects on satellites, electronics, and electrical systems. DSCOVR replaces NASA’s aging Advanced Composition Explorer (ACE) satellite, which launched in 1997 and performed the same solar-monitoring job.

The second part of DSCOVR’s mission, to beam a live, full-disk image of our planet back to Earth, was originally conceived in 1998 by former Vice President Al Gore. The proposed satellite was constructed originally named Triana (after Rodrigo de Triana, the crewman who was the first to sight land during Christopher Columbus’ voyage to America in 1492) but later shelved. Triana was later dusted off, refurbished, repurposed, and renamed DSCOVR.

The other noteworthy aspect of the DSCOVR launch was SpaceX’s second attempt at a first-stage booster recovery under even more challenging conditions as their first attempt in January. After lofting DSCOVR toward its deep space parking spot, the Falcon 9 rocket should return faster, experiencing greater deceleration forces and higher reentry heating. Although the rocket seems to have survived more challenging reentry, rough seas rendered conditions unacceptable for a dry landing, as the floating spaceport platform could not maintain stability in waves reaching heights of 30 feet. Nevertheless, SpaceX was able to demonstrate pinpoint guidance, bringing the spent Falcon 9 rocket stage to a splash-landing 10 meters from the intended spot. –Bing Quock

Active SETI

Will intelligent life from another planet be altruistic or dangerous, as Steven Hawking proposed a few years ago? “We only have to look at ourselves to see how intelligent life might develop into something we wouldn’t want to meet,” he said in a documentary at the time.

It’s an excellent question and one that was part of a very lively discussion at this year’s AAAS (American Association for the Advancement of Science) meeting, held in San Jose. The panel presenting was in favor of pushing messages out to the Universe to communicate with these unknown aliens—an “existential risk” worth taking, said astrobiologist David Grinspoon of the Planetary Science Institute.

The session was in support of an “Active SETI.” The SETI Institute has been listening for extraterrestrial intelligent life for 50 years, pointing radio telescopes to the stars, SETI’s Douglas Vakoch explained at the conference. “But it’s been very passive, waiting for signals,” he said. “Now we want to reverse the process, and send powerful, information-rich signals to others.”

Given Hawking’s concerns, this is a bit controversial. But as Vokoch pointed out, intelligent life can already pick up our radio and television signals, dozens of light years away—“radio leakage” is how the group described this.

Grinspoon explained why now is a good time for Active SETI, including: the recent discoveries of extremophiles on Earth, all of the exoplanet discoveries (“evolution could be happening in many different places”), and our own question of sustainability on this planet. “In the Anthropocene, we’re facing the question of sustainability of human civilization, and other civilizations elsewhere must have similar questions… Anyone that we’re likely to encounter has been around longer than we’ve been around.”

Vakoch added later that SETI founder Frank Drake believes that intelligent species do have a limit of 10,000 years, so “on average,” Vakoch said, “other intelligent lifeforms are likely to be thousands of years more advanced” than we are.

Much of the discussion centered on involving the international community in this active form of communication. “Of course we should [get feedback from the community], that’s apple pie and motherhood,” said SETI’s Seth Shostak, but obtaining an agreement would be very difficult. “What would the decision metric be?” Some in the panel remarked a good example of a group message to alien life is the current One Earth Project, to be sent via the New Horizons satellite when it leaves the Solar System.

Do you want to be part of the controversial discussion? Join the panel and others at the Active SETI workshop at the SETI Institute tomorrow. Who knows what you’ll hear? –Molly Michelson

Watching Sibling Stars Form

Within a dark dense cloud in the constellation Perseus, astronomers are watching something never before seen—a multi-star system under development and in the midst the complex process that will eventually yield a system of at least two stars, maybe four!

By turning huge radio telescopes towards this cloud, the scientists resolved a structure that only previously existed in computer models predicting how companion stars are formed. The mere fact that the model so closely fits the observation means that scientists are truly close to seeing how multiple stars are born and grow together.

But radio telescopes specialize in observing cool dust and gas—surely newborn stars must be very, very hot? Surprisingly enough, the cloud of material from which these stars are forming has to be fairly cool so it is stable enough to collapse into the blobs and filaments that will later give rise to the hot newborn suns.

Since binary stars are so common (astronomers currently understand that more than half of all stars have one companion… or more!), why has it taken scientists so long to observe a nascent twin system? It is possible that some of the other infant stars we have imaged are binaries, but within the protostellar birth cloud it can be difficult to decipher exactly what is going on. The region in Perseus, known as Barnard 5, is diffuse enough to provide us with this exciting data.

How many stars will eventually form here? How long will it take? Will there be planets? These questions make take many lifetimes to resolve (about 40,000 years!) but by observing the early stages of this system, we may get the data we need to make more predictions based on better and better models. The more information we glean from golden opportunities like this, the closer we get to understanding why our star has no companion, how our planet formed and how our star fits into the grand scheme of the stars of the Milky Way. -Josh Roberts