StarDate

For the people of the Soviet Union, Soyuz 11 was a novelty. State media provided regular updates on the space mission, which was rare. It even showed TV broadcasts of the three cosmonauts showing off some plants they were growing, and celebrating a birthday with prune paste and presents of an onion and a lemon.

Pride in the mission turned to grief, though, when Soyuz 11 returned to Earth. When recovery forces opened the hatch 50 years ago yesterday, all three cosmonauts were dead.

Georgi Dobrovolsky, Vladislav Volkov, and Viktor Patsayev had launched on June 6, 1971. They docked with the first space station, Salyut 1. They spent a record three weeks aboard the station. They operated a telescope, observed Earth, and conducted secret experiments for the military.

When their work was done, they packed up for home. They separated their Soyuz capsule from the station, then split off their reentry module for the plunge through the atmosphere. No one knew it at the time, but that part of the process went horribly wrong. A valve opened and let the air escape into space. The cabin was too cramped for the cosmonauts to wear spacesuits, so they died in seconds.

The automated landing system worked well, though, and Soyuz 11 touched down as expected. Recovery forces quickly reached the capsule, but heard nothing from the crew. When they opened the hatch, they found the cosmonauts dead — a tragic end to a record-breaking stay in space.

Script by Damond Benningfield

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Horror movies often inspire sleepless nights. But one that had its American premiere 75 years ago this week inspired something different: a new model of the universe.

“Dead of Night” was a British production. In it, an architect is invited to a country house for the weekend. Although he’s never met any of the people there, he recognizes them from a series of nightmares, which he recounts. At the end, he murders one of the people. He then awakens and realizes it was all a dream. But he then gets a phone call inviting him to the house — starting the nightmare all over again.

Three British physicists — Thomas Gold, Hermann Bondi, and Fred Hoyle — were pondering the beginning and end of the universe. They knew that the universe was expanding, but they didn’t agree with the idea that it had a single point of origin. Hoyle even called the theory the “Big Bang” as a term of derision. Instead, they thought the universe had neither a beginning nor an end.

After they saw the movie, Gold wondered whether the universe might be similar — constantly “starting over.”

So they came up with their own theory of the universe — the Steady State Theory. It said that matter was constantly being created as the universe expanded. That way, the universe would maintain a constant density. And it would just keep going — forever.

Observations confirmed the Big Bang, though, leaving the Steady State alone — in the dead of night.
 

Script by Damond Benningfield

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The brilliant planet Jupiter leads the Moon across the sky late tonight. It’s to the upper right of the Moon as they climb into good view, after midnight.

Jupiter is the largest planet in the solar system. It’s about five times as far from the Sun as Earth is. But it probably hasn’t always been at that distance. Models show that it probably moved much closer to the Sun early on, then backed away.

Jupiter-sized planets in some other star systems may have moved even more. In fact, it’s possible that they switched stars.

A recent study looked at a system known as Gliese 3512. It consists of a tiny, feeble star plus a planet at least half as massive as Jupiter. The problem is, there doesn’t appear to be a way for such a heavy planet to form around such a little star. The gravity of the star wouldn’t allow enough material to come together to make such a world.

So researchers suggested another way for a little star to get a big planet: a swap with another star. In the crowded confines of a young star cluster, stars frequently pass close to each other. If a small star flies near a Sun-like star with a Jupiter-like planet, the planet could switch partners — it could leave its parent star behind and be adopted by the smaller star.

Gliese 3512 isn’t the only system where a small star has a big planet. That suggests that planet exchanges could be common, with planets frequently switching stars inside busy clusters.
 

Script by Damond Benningfield

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The solar system gets the week off to a beautiful start early tomorrow. The Moon will form a wide triangle with the planets Jupiter and Saturn. The trio will climb into view after midnight and stand high in the south at first light. Jupiter is the brighter of the two planets, and stays to the left of the Moon, with Saturn to the right of the Moon.

Jupiter and Saturn are the largest planets in the solar system. And not surprisingly, they have the largest collections of moons — almost 80 for Jupiter, and more than 80 for Saturn.

Many of those moons have been discovered just in the last couple of decades. That’s because most of them are tiny — no more than a few miles in diameter — so they’re faint. And they’re a long way out from the planets, so astronomers have to search a large area to find them.

Some of the little guys probably were asteroids that were captured when they passed close to one of the planets. And some appear to be remnants of larger moons that were blasted to bits by collisions.

Instead of Greek and Roman mythology, the names for some of the moons of Saturn have been drawn from other cultures — Gallic, Norse, and Inuit. And some moons of both worlds haven’t been named yet. In some cases, that’s because astronomers are waiting for confirmation that the moons actually exist. Until then, they’re stuck with catalog numbers — waiting for full membership in these giant families of moons.

Script by Damond Benningfield

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Other than Earth, there’s no place in the solar system that says, “there’s life here!” But there are several places that whisper, “there could be life here.”

One of those is Titan, the largest moon of Saturn. Its dense atmosphere and its rocky interior are loaded with the chemical building blocks of life. And the moon probably has a global ocean of liquid water below a thick icy crust. If the different layers get together, then Titan would have the basic ingredients for life.

Titan is about half again the size of our own moon. It’s extremely cold. But its atmosphere is thicker than Earth’s. It’s topped by an orange “smog” made of organic compounds — the chemistry of life. The atmosphere consists of another organic compound, methane, plus a lot of nitrogen that came from organics.

Models of Titan say it has a deep ocean of liquid water buried far below the surface. Impacts by giant space rocks might punch holes in the crust deep enough to allow organics from the surface to reach the ocean. On the other hand, organics might enter the ocean from below — through mineral-rich fountains of hot water like those found on Earth. Either method would provide water, organics, and energy — the basic ingredients for life.

Saturn is close to the upper left of our moon as they climb into good view, by midnight. It looks like a bright star. Titan is visible through good binoculars or a telescope, shining like a tiny star next to the giant planet.
 

Script by Damond Benningfield

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If you like black holes, you might want to check out the core of NGC 6397, a giant ball of stars almost 8,000 light-years away. A recent study says the core could house dozens of black holes.

NGC 6397 is a globular cluster. It contains hundreds of thousands of stars. But the stars are ancient — as old as the Milky Way Galaxy.

All of the cluster’s big, heavy stars expired billions of years ago. When those stars died, they left small but heavy remnants — white dwarfs, neutron stars, or black holes. And in a cluster, such massive objects sink to the middle.

Earlier studies had suggested that there’s a small, dark mass at the center of NGC 6397 — perhaps a black hole a few hundred times the mass of the Sun.

The more recent study used the Hubble and Gaia space telescopes to plot the orbits of stars in the cluster. The way the stars move suggests they’re orbiting a large group of stellar remnants, not a heavier single black hole.

They total up to about 2,000 times the mass of the Sun. Most of that mass should consist of black holes. They range up to about 40 times the mass of the Sun. Black holes ought to occasionally kick out a normal star, or even merge with each other — stirring things up in this ancient cluster.

NGC 6397 is in Ara, the altar. From the U.S., it’s visible only from Hawaii and southern Texas and Florida. It’s in the south around midnight.
 

Script by Damond Benningfield

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That’s the sound of the winds of Mars, recorded by the Perseverance rover after it landed in February. It’s the first direct recording of sounds in the Martian atmosphere.

Scientists have been monitoring the Martian winds off and on for decades. Most American landers have included a weather station. Today, there are three working landers with weather stations.

Most of the time, the wind is tame, with speeds of only a few miles per hour. But during winter it gets a little friskier. And for the InSight lander, that’s too much — the wind can overpower the faint rumblings of marsquakes, which InSight is designed to study.

In one way, though, the wind hasn’t been strong enough. Scientists were hoping that dust devils might blow the dust from Insight’s solar panels. By earlier this year, though, they hadn’t. So InSight’s workload was cut back — including shutting down its weather station — until Mars moves closer to the Sun, which will provide more life-giving sunlight.

Sometimes, the wind stirs up giant dust storms. Some of them can cover most of the planet, driven by winds of 60 miles per hour or stronger. In 2017, such a storm darkened the sky enough to kill the solar-powered Opportunity rover.

Perseverance and the other working rover, Curiosity, don’t have to worry about that. They use nuclear power — protecting them from the vagaries of the Martian winds.
 

Script by Damond Benningfield

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If you have a pair of binoculars, this evening is a good time to break them out. They’ll provide an excellent view of Mars passing in front of a star cluster known as the Beehive. They’re quite low in the western sky as night begins to fall, to the upper left of bright Venus, the “evening star.”

The Beehive contains perhaps a thousand stars. They’re packed into a loose ball a couple of dozen light-years in diameter. But the cluster is about 600 light-years away, so to the eye alone it looks like a hazy smudge of light. Binoculars reveal a couple of dozen individual stars.

The Sun probably was born in a cluster, too. Over time, though, clusters lose many of their stars. They’re pulled away by the combined gravity of other stars and gas clouds in the galaxy. So most of a cluster’s original stars soon go their own way — just as the Sun did.

The Sun was born about four and a half billion years ago. So far, no one knows if any of its birth cluster is still around — it could have disappeared a long time ago.

But a study last year suggested that the Sun could have been born in a cluster like the Beehive. Researchers said that such a birthplace would account for some of the traits of the present-day solar system.

We may never know just what the Sun’s birthplace was like. But scanning the Beehive with binoculars could be like looking into the old homestead — a cluster much like the one that gave birth to the Sun.

Script by Damond Benningfield

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If you gaze into the summer night sky in a million years, it’ll look a lot different than it does tonight. For one thing, the Sun and all the other stars are moving. The change in position isn’t fast enough to notice over a human lifetime, or even many lifetimes, but it adds up. In a million years, many of the stars that are visible now will have moved so far away that they’ll be out of sight. At the same time, other stars will have moved into range.

Another reason for the change is that some stars may no longer exist — they may blow themselves to bits by then.

A leading candidate is Antares, the brightest star of Scorpius. It’s close below the Moon at nightfall. It’s perhaps a dozen times the mass of the Sun, hundreds of times wider than the Sun, and tens of thousands of times brighter.

Antares is only about 15 million years old — a third of a percent of the age of the Sun. Because of its great weight, though, it ages far faster than the Sun does, so it’s already nearing the end of its life.

Before long — perhaps within the next million years — Antares will no longer be able to produce nuclear reactions in its core. The core will collapse to form an ultra-dense neutron star. The star’s outer layers will fall inward, then rebound. They’ll blast out into space, forming a brilliant supernova. As the supernova fades, Antares will disappear from view — one more change in the constantly changing night sky.

Script by Damond Benningfield

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Nancy Roman and Vera Rubin heard it many times: astronomy isn’t for girls. Neither of them paid much attention, though. Instead, they kept chasing the stars. They became two of the most accomplished and respected astronomers of their time. And today, they’re the namesakes for two major facilities — the first women to receive such an honor.

The Nancy Grace Roman Space Telescope is scheduled for launch later this decade. Among other chores, it’ll study dark energy and search for planets in other star systems.

Roman was born in 1925. In 1960, she became the first chief astronomer for NASA — a post she held for almost two decades. She oversaw development of several space telescopes, and was a driving force in the early years of the Hubble telescope. She also oversaw projects that lofted telescopes on balloons and airplanes.

The Vera Rubin Observatory features a giant telescope that’s under construction in Chile. When completed, the telescope will snap pictures of the entire sky about every three nights. Comparing images will allow astronomers to study variable stars, discover asteroids, probe dark energy and dark matter, and more.

Rubin was born in 1928 and became a leader in studying galaxies. Her observations of the motions of spiral galaxies helped confirm the existence of dark matter.

Roman and Rubin also were strong advocates for women in science, helping many women — and girls — understand that astronomy is for them.

Script by Damond Benningfield

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