This Week in Space: Falling Stars (and Rocket Stages)

Good morning, space nerds. Would you like some space debris with your morning coffee? This week, China launched its Mengtian module, completing its Tiangong space station — and leaving behind yet another twenty-ton piece of free-falling space junk, timed to go right along with breakfast this morning and targeting the Gulf of Mexico.

NASA announced that InSight’s days are numbered, as the spacecraft finally succumbs to the Martian dust. But we’ve got updates from Artemis — including news from CAPSTONE and Psyche. We’ll discuss reports of a new and potentially threatening space rock nearly a mile wide. Plus, astronomers report discovering an “extragalactic structure” behind a murky region of space known as the zone of avoidance. We’ll wrap up with a special edition of Skywatchers Corner, en homage to three currently active meteor showers.

China Completes Tiangong Space Station

China’s Mengtian module docked successfully with the Tiangong space station earlier this week. Mengtian is the third and final module of the T-shaped space station. Like the other two modules, it launched aboard a Long March 5B rocket. And, like the other two Long March rockets, this one left behind a several-thousand-pound rocket stage fated to make an inevitable, uncontrolled re-entry.

Mengtian launched on Oct. 31. The remainder of its Long March rocket will splash down in the Gulf of Mexico on Friday morning, local time. However, because orbital speeds are very fast, just a few moments’ uncertainty can add up to thousands of kilometers of distance. As of Thursday night, we still had a nearly four-hour error bar.

Scientists Find Galaxy Cluster Hidden Behind ‘Zone of Avoidance’

In a pre-print report on arXiv, astronomers announced that they had discovered an “extragalactic structure” hidden behind a region of the sky known as the zone of avoidance.

The zone of avoidance (ZoA) is the part of the sky obscured by the central bulge of the Milky Way. This area is so dense with stars, gas, and dust that most instruments can’t see through to the other side, and it accounts for between 10 and 20 percent of the sky.

By “extragalactic structure,” they mean the large-scale structure of the region: specifically, a large cluster of galaxies, something like our Local Group. The researchers named their galaxy cluster VVVGCl-B J181435-381432, which — honestly — are y’all sure that wasn’t just someone’s cat walking on their keyboard?

The astronomers found the galaxy cluster using the ESO’s Visible and Infrared Survey Telescope for Astronomy (VISTA) at Paranal, along with follow-up observations made with the Gemini South telescope (also in Chile) and its FLAMINGOS-2 infrared detector.

Scientists Find Potential ‘Planet-Killer’ Asteroid Hiding in the Sun’s Glare

Speaking of big things hiding behind other big things, astronomers have found three new near-Earth asteroids (NEAs), one of which is the biggest such rock we’ve found in the last eight years. The astronomers used the ultra-sensitive Dark Energy Camera, on the Víctor M. Blanco 4-meter Telescope in Chile. It can only make its observations during a ten-minute window at dawn and dusk. With this instrument, the astronomers were able to look past the glare of the sun and spot the three new NEAs: 2021 LJ4, 2021 PH27, and 2022 AP7.

2021 LJ4 and 2021 PH27 are of little concern. Even so, they’re scientifically interesting. Surface temperatures on 2021 PH27 get hot enough to melt lead. However, 2022 AP7 is nearly a mile wide — and it crosses Earth’s orbit. We don’t know how serious a threat it poses yet, because there’s still a lot of uncertainty. But there’s a possibility it could find itself in the same place as Earth about a thousand years hence.

Catch Me If You Can? Challenge Accepted

Rocket Lab will launch a satellite to orbit — and try to catch its Electron rocket’s spent booster with a helicopter — later today (Nov. 4).

The company is calling the mission “Catch Me If You Can.” It will launch on Friday from Rocket Lab’s New Zealand launch facility, during a 75-minute window that opens at 1:15 PM EDT (1715 GMT, or 6:15 AM on Nov. 4 local New Zealand time).

The rocket will be carrying a research satellite for the Swedish National Space Agency (SNSA). The satellite, MATS (short for “Mesospheric Airglow/Aerosol Tomography and Spectroscopy”), is part of the SNSA’s efforts to “investigate atmospheric waves and better understand how the upper layer of Earth’s atmosphere interacts with wind and weather patterns closer to the ground.” That’s cool, for sure. But the mission has a remarkable B plot. Even though all parts of this rocket are expendable, Rocket Lab aims to catch the free-falling rocket stage with a helicopter. Why? The company’s long-term goal is to fly reusable rockets. Catching them in midair would keep the vehicle from exposure to corrosive seawater. It could also present Rocket Lab with an easier way of retrieving rocket parts for analysis and reuse down the line.

You can watch the launch livestream here, courtesy of Rocket Lab. Coverage will begin at T – 20 minutes, and the catch should go down a little less than 20 minutes after takeoff.

Martian Dust Spells the End for InSight Mars Lander

It had to happen sometime. Enough dust has built up on NASA’s InSight Mars lander that the InSight team is preparing to formally end the mission. Earlier this summer, dwindling power reserves had already forced the team to turn off all but the lander’s seismometer. Recently, yet another dust storm added yet another layer of dust on the lander’s solar panels. To cope with the restricted power budget, the mission turned the seismometer off altogether. It’s recording again, but mission specialists say it won’t be long — perhaps a few weeks — before the lights go out for good.

InSight’s seismometer has detected more than 1,300 marsquakes since the lander touched down in November 2018. The largest measured a magnitude of 5. The lander even recorded quakes from meteoroid impacts. In a statement, NASA noted that “observing how the seismic waves from those quakes change as they travel through the planet offers an invaluable glimpse into Mars’ interior but also provides a better understanding of how all rocky worlds, including Earth and its Moon, form.”

“Finally, we can see Mars as a planet with layers, with different thicknesses [and] compositions,” said Bruce Banerdt, the mission’s principal investigator. “We’re starting to really tease out the details. Now it’s not just this enigma; it’s actually a living, breathing planet.”

“We’ll keep making science measurements as long as we can,” Banerdt added. “We’re at Mars’ mercy. Weather on Mars is not rain and snow. Weather on Mars is dust and wind.”

Space Image of the Week: the Vela Supernova Remnant

Earlier this week, the European Southern Observatory (ESO) released this gorgeous image of the Vela supernova remnant.

To get this giant 554-MP image out of the telescope’s 268-MP CCD, researchers made a cleaned-up composite of many overlapping images of the same bit of sky.

For the curious, there’s also a video fly-through of the image:

My colleague Ryan Whitwam writes: “Until about 11,000 years ago, there was no Vela supernova remnant. This structure is the product of a type II supernova, which marked the end of a massive star. That star is now an ultra-dense neutron star — technically a pulsar as it’s rotating more than 11 times per second. It’s the brightest pulsar (in radio frequencies) in the sky, and has one of the fastest rotations known. The image from the ESO doesn’t focus on the pulsar itself but rather on the massive cloud of energized gas that makes up the supernova remnant.”

Artemis Updates

It looks like NASA will in fact be making their next Artemis launch attempt toward the end of the Nov. 12-14 launch window. During a Thursday teleconference, officials confirmed that they will make their next attempt at 12:07 AM on Nov. 14.

“If we weren’t confident, we wouldn’t roll out. If we weren’t confident, we wouldn’t start the countdown when we do so. We’re confident moving forward,” said Jim Free, an associate administrator at NASA’s headquarters in Washington, D.C.

The agency also announced this week that its pint-sized CAPSTONE probe is back on track for its mission to the moon. The CAPSTONE probe is indispensable to the Artemis program. However, the “beefed-up cubesat” has been experiencing some problems. In September, an orbital maneuver sent the probe spinning in an uncontrolled tumble that left it unable to contact Earth. Worse, it was losing more power than it could generate with its solar panels. It could have been game over, but Advanced Space (which manages the probe for NASA) reported this week that CAPSTONE has made a successful course correction.

Now that the satellite is back under control, it will trace out a long, looping path that will eventually deliver it into an ambitious near-rectilinear halo orbit (NRHO) around the Moon. There, it will test the NRHO for viability, paving the way for the Lunar Gateway that will enable Artemis flights to lunar orbit, and eventually to the surface of the Moon.

NASA officials also confirmed that Psyche, which was supposed to launch as a ride-along aboard Artemis 1, will now launch in October 2023. When the SLS missed its August launch window, Psyche did too — only Psyche has very different launch windows. With this new launch time frame, the spacecraft will arrive at Psyche in August 2029.

Skywatchers Corner Special Edition: Meteor Showers

There’s so much going on in the night skies this week that our Skywatchers Corner might just take up an entire room. To start with, we’ve got several meteor showers at the same time — so your odds of seeing a shooting star are particularly good right about now. Here are the standouts:

The Leonids: November 3 – December 2

Emanating from a point near the constellation Leo, the Leonids are associated with the comet Tempel-Tuttle. This yearly shower creates spectacular meteor storms that occur about every 33 years. This year, we might expect to see ten to fifteen meteors per hour from the Leonids. It’s an off year. But during its peak years, the Leonid meteor shower can produce thousands of meteors per minute. During a fifteen-minute span on the morning of November 17, 1966, EarthSky.org writes that the Leonid meteors “did, briefly, fall like rain. Some who witnessed it had a strong impression of Earth moving through space, fording the meteor stream.”

This year’s Leonids will peak on or about November 18. On that night and the night before, optimal viewing conditions will come during a short window of dark skies around midnight between the rise of Leo and the waning crescent Moon. Alas, we won’t see a peak year for another decade or so.

The Taurids: October 20 – November 30

The Taurids are actually one of the year’s longest meteor showers, appearing around Oct. 20th and lasting until the end of November. But this week, from November 5 – 12, the Taurids are at their peak. Like the other meteor showers we’re spotlighting here, the Taurids tend to produce long, dramatic, streaking fireballs that can leave a brilliant trail stretching across half the sky. They’re probably from the periodic comet Encke.

The Taurids are actually two different showers: the Northern and Southern Taurids, respectively. This is an example of what happens to a comet and its debris trail, late in its life. The slightest divergence in path between a comet and its debris adds up over time. As the positions of the planets are constantly changing, an orbiting comet’s debris will pass nearer to them on some revolutions than others. This pulls apart and diverts the streams, fanning them out into more of a cloud. After tens of thousands of years, there’s enough of a spread that these meteors are active for up to six weeks.

The Orionids: Early October – November 30

Like the Taurids, the Orionids come from a comet resembling the many-tailed kitsune of Japanese legend. In 1986, Halley’s Comet showed up with no fewer than seven tails. Between its many tails and its spiraling path, the great comet has created an intricate web of debris trails in its wake. Every year, we pass through the debris trail of Halley’s Comet, which we see as the Orionid meteor shower.

This year’s Orionids are on their way out, but just like the Taurids, the Orionids will slowly taper off through the end of November. They’re still going strong; Wednesday night, a meteor burned up in the sky over central New York. Based on the fireball’s origin and direction, it was most likely one of the Orionids.

This year’s midterm elections fall on Tuesday, Nov. 8. However, that day also features a total lunar eclipse, and it’s the last chance to see one until 2025. The eclipse will be visible from anywhere that has a view of the moon during the hours before sunrise on the morning of Nov. 8.

For viewers on the East coast, the eclipse will begin shortly after 4 AM, reaching full eclipse at about 5:15 AM local time. The moon will set while still in eclipse. However, on the West coast, that translates to the partial phase beginning just after 1 AM, and totality beginning at about 2:15 AM. Viewers in the Western time zone will be able to see the entire eclipse take place, with the Moon exiting the dark part of Earth’s shadow (the umbra) just before 5 AM.