When one of the workhorses of Russia's space program took to the sky from Baikonur Cosmodrome last weekend with a payload of Russian and German space telescopes, it was carrying one of humankind's most daring efforts to map the universe.
Within about 100 days, when engineers hope the equipment fully awakens as a double-barreled observatory in deep space, the eROSITA and ART-XC X-ray telescopes should start stitching together at least four rounds of a pioneering, sky-wide X-ray of the cosmos.
It will be peering at galaxy clusters, millions of supergiant black holes, and countless other "populations" up to 10 billion light years away in ways that can reveal a lot about the evolution and future of the universe.
Its data could also provide clues to the existence of dark energy and dark matter, which makes up the vast majority of the universe's mass but whose existence is mostly just inferred by its gravitational effect on what we see.
It's a major foray for Russia into the world of deep-space observation, carried aloft by a Russian rocket following a series of recent setbacks to that country's space program.
Astrophysicists, cosmologists, and other scientists around the world can't wait to see the results.
But far longer than its three-month, 1.5 million-kilometer trip to "halo orbit" around the L2 Lagrarian point shielding it from the sun, one of the former Soviet architects of Russia's ambitious project has already waited three decades for that moment.
The mission's driving goal -- "hard" X-ray observatories in space -- was initially encouraged by a cluster of leading Soviet scientists 32 years ago.
Reportedly led by Tashkent-born astrophysicist Rashid Sunyaev, the group included Yakov Zeldovich, a Minsk-born physicist who was a key architect in the Soviet nuclear weapons program, along with nuclear physicist and Soviet human rights activist Andrei Sakharov.
They pitched the idea to Soviet leader Mikhail Gorbachev in 1987, and international efforts began toward its realization.
But the plan for this Soviet-inspired breed of observatories was left for dead, in Sunyaev's words, when the Soviet Union disintegrated in 1991.
Sunyaev, now the lead scientist for the Russian side on the Spektr-RG mission, is the only one among its three Soviet initiators to have survived to see it get off the ground.
Now at the Max Planck Institute for Astrophysics in Garching, Germany, he was contacted by RFE/RL but declined to comment for this article other than to say he has been very happy since the launch.
A New Threat
As recently as five years ago, with the joint Russian-German mission well under way, fresh doubts threatened to keep the project earthbound.
Russia's invasion and annexation of Ukrainian Crimea and Moscow's hand in the ongoing separatist-fueled conflict in eastern Ukraine has brought punishing sanctions and political isolation of Russia by Germany and the West.
"It made us nervous," Peter Predehl, head of Germany's extended ROentgen Survey with an Imaging Telescope Array (eROSITA) team, told RFE/RL this week.
Germany was committed, but dependent upon Russian rocket power in order to haul its eROSITA into deep space and start looking for black holes and dark matter.
Weighing nearly a ton and bristling with cutting-edge, radiation-resistant electronics and high-precision mirrors unlike just about any other in the world, the eROSITA was a hulking structure loaded with potential dual-use technology.
"This is the ultimate technology that we are using," said Predehl, who also heads the high-energy astrophysics group at the Max Planck Institute for Extraterrestrial Physics in Garching, a suburb of Munich.
In the words of German Aerospace Center executive board member Hohann-Dietrich Woerner at the signing of the agreement in Moscow in 2009 with Russia's Roskosmos aerospace agency to put eROSITA into space, the Spektr-RG mission is "a beacon project of scientific collaboration in space between Russia and Germany."
But with political and trade relations hitting turbulence, the Germans had to proceed cautiously if they wanted to get eROSITA to Russia, and then Kazakhstan, for launch.
"We asked both the U.S. exporting authorities as well as the EU ones, 'Do we have a chance, or are we allowed to export eROSITA?'" Predehl said. "In the end, we did, we got the permission."
Fast-forward to late May and Predehl was at Baikonur for the first of what would eventually be three trips to watch "our baby" launched into space.
Predehl even issued a rare tweet of an image taken as he and other team members entered the facility "to say goodbye" to eROSITA, which by that point stood mounted side-by-side with the Russian telescope, ART-XC, and the Navigator satellite on the upper stage of the Proton rocket.
"That was excitement, pure excitement. Because when we built eROSITA -- it's a huge instrument, it's like a car. It had almost a ton of weight and it's a very complicated thing. It's almost 4 meters tall, 2 meters in diameter. But then, mounted on the spacecraft together with the Russian telescope, it became tinier. And then, mounted on this upper stage [of the Proton M], it became really tiny. It's huge. Everything that we saw was huge."
The launch dates were postponed at least twice.
"Baikonur, in Kazakhstan, became my third home," he said of his trips in anticipation of liftoff.
But reports suggested a trouble-free launch on July 13, despite delays that included a pressure leak in the rocket's second stage, according to TASS.
Success came as a relief to a Russian space program that has suffered several setbacks in recent years, including a close call for Russian and American astronauts when their Soyuz rocket malfunctioned during an effort to reach the International Space Station in October.
Mikhail Pavlinsky, head of high-energy astrophysics for the Russian Academy of Sciences' Space Research Institute (IKI) in Moscow, told Nature magazine that Spektr-RG was Russia's "new chance to return to world-class science."
Eagerly Awaited...And Awaited?
Coverage since the launch has reflected enormous anticipation of what the world will learn after what Predehl called "the holy moment for a telescope and its [principal investigator]," in this case him.
Astronomers and other scientists are keen to view space through Spektr-RG's lenses -- think of seeing infrared or night-vision images as opposed to normal daytime pics -- with ambitious goals in mind once they can essentially see 5 billion to 10 billion years back in time.
The uniqueness of what's known as the Spektr-RG mission lies in its instruments' sensitivity to so-called "hard" X-rays -- as opposed to lower-energy radiation -- and its ability to observe the entire sky at once.
"It's going to be revolutionary in terms of numbers," ScienceMag.org quoted astronomer George Lansbury of the Institute of Astronomy (IoA) in Cambridge as saying, citing the new "big data regime" of X-ray space studies.
But not all of the conclusions from that data will emerge as seamlessly as the complete-sky images that the Spektr-RG mission aims to produce.
Nature magazine described as "unusual" a deal on handling the resulting data that Sunyaev says was intended to support Russia's small astrophysics community. It will divide the sky into a German half, west of the Galactic Center, and a Russian half, east of the Galactic Center, the magazine said.
Again, Sunyaev did not comment for this article, including any remarks about the half-and-half arrangement.
Predehl, the German lead scientist, clarified that both sides will get all the data and it will be "digested" by German-developed software.
But the so-called scientific usage, including publication of findings, will in fact be split -- for at least a time -- under the joint partners' agreement.
"That was, from the beginning, the price we had to pay -- half of the sky, 50 percent of the data," Predehl told RFE/RL. "This is the price we had to pay, from the beginning, for getting eROSITA launched."