The European Space Agency’s (ESA) flagship mission to Jupiter and its icy moons is underway.
But after the successful launch of the JUICE (Jupiter Icy Moons Explorer) spacecraft, what’s next for the 1.6 billion euro ($1.77 billion) mission to Jupiter?
After blasting off into the sky above Europe’s spaceport in French Guiana, JUICE now embarks on an eight-year journey that will see it perform fly-bys of Venus and Earth to gain gravity assists that will accelerate it to an encounter with Jupiter in 2031.
But the long journey does not mean that mission scientists will get to put their feet up for eight years. In fact, their work is just beginning.
“It would be nice to forget about it for eight years, but we’ll be kept pretty busy planning and replanning,” said Randy Gladstone, of the South-west Research Institute in San Antonio, Texas, in an interview with Space.com. Gladstone is the Principal Investigator on JUICE’s Ultraviolet Spectrograph (UVS), which is one of NASA’s contributions to the JUICE project.
JUICE will return to Earth in August 2024 for a fly-by and gravity assist that will then send it in-system to a rendezvous and another gravity assist at Venus in August 2025. Two more gravity assists with Earth will take place in September 2026 and January 2029, the latter one taking advantage of the dance of the planets and sending JUICE on its way at high speed towards Jupiter.
While all this is happening, mission scientists have to learn about how the spacecraft and their instruments work. Although the instruments have been checked out in the laboratories where they were built on Earth, their performance for real in space can create complications.
Learning how the instruments work will be “the first thing to do,” said Gladstone. On the spacecraft, the various instruments may begin to impact each other. For example, one instrument next to another might warm up more than its neighbor prefers, affecting the other instruments’ functionality, while in the micro-gravity of space the whole spacecraft relaxes leading to small changes in alignment.
To calibrate everything, the instrument teams will use carefully chosen target stars that have very stable and well-known properties. In particular, Gladstone’s team will compare the known spectra of the stars with what UVS observes, proceeding to fine-tune the instrument until the observations match the spectra on file.
Some of the calibration of the various instruments will also take place during the fly-bys of Earth and Venus, although testing is limited within two astronomical units of the sun (twice the distance of Earth from the sun, a little bit beyond Mars‘ orbit). While in the inner solar system, JUICE will shield its instruments from the sun by using its antenna dish like a parasol. Were the instruments exposed to the bright sun by accident, they could be damaged beyond repair, and so pointing the instruments while close to the sun is prohibited.
“At Venus [the sun] is too hot for us to even operate, but the Earth fly-bys later will be very valuable for calibration and getting ready for Jupiter,” said Gladstone.
After its final fly-by of Earth, JUICE will be slingshot on a trajectory towards Jupiter. By this time it will have been overtaken by NASA’s Europa Clipper mission, which launches in October 2024 and arrives at Jupiter in April 2030, one year ahead of JUICE.
JUICE won’t simply be a bystander while Europa Clipper is in action at Jupiter, where it will possibly join NASA’s Juno spacecraft that has been in orbit around Jupiter since 2016, assuming it is still functioning. JUICE will be able to provide early warning for both Europa Clipper and Juno if there is a powerful and potentially harmful solar flare directed at Jupiter.
A year before Jupiter orbit insertion (JOI), “we’ll ramp up the team to start making observations,” said Gladstone. “They won’t all be of Jupiter, but they’ll be similar to what we will be doing at Jupiter, so we’ll spend a lot of time practicing with the instruments, and planning. There’s a lot of stuff we can do, but the planning is the big thing.”
Coordinating which instruments will be doing what and when during the 35 fly-bys of three of Jupiter’s moons (two fly-bys of Europa, 12 of Ganymede and 21 of Callisto) will require much negotiation between the various instrument teams as well as those responsible for the spacecraft’s fuel and power supplies.
“We’re all pretty agreeable, but it’s still a lot of work to sort out what we’re going to do second-by-second for the five years that we’re there at Jupiter,” said Gladstone. “But we’ll figure out the best way to get the best science for each fly-by.”
From Gladstone’s point of view, the UVS is concerned with mapping ultraviolet emissions. It does this by passing ultraviolet light through a slit, after which it hits a diffraction grating that spreads out the light into its various ultraviolet wavelengths — a spectrum.
“Most matter interacts really strongly with ultraviolet light, and [UVS] is very sensitive to tiny amounts of gases, which is sort of what Jupiter’s moons have for atmospheres,” said Gladstone.
These tenuous atmospheres — referred to as ‘exospheres’ — cling to the moons, sputtered off their surface by micrometeorite impacts. They can be observed either directly through their ultraviolet emissions when atoms and molecules are excited by collisions with charged particles that fizz around Jupiter’s powerful magnetosphere, or indirectly by watching a moon’s exosphere absorb some of the light of a star or the sun during an occultation. The wavelength absorbed gives away the identity of the atom or molecule doing the absorbing.
Meanwhile, ultraviolet sunlight reflected by the moons can give away details about their surfaces.
“UVS will tell us a lot about the surface composition and structure,” said Gladstone. “We know the surfaces are icy, but there’s a lot of other materials down there besides the ice.”
UVS will also be able to study the ultraviolet auroras that flicker around the magnetic poles of Jupiter. These auroras have previously been observed by the Hubble Space Telescope, the James Webb Space Telescope and by Juno. However, Hubble and James Webb cannot keep a constant eye on the auroras, and Juno spins on its axis to maintain its stability, meaning that its instruments cannot linger on the auroras long enough to see the fainter ones.
“With JUICE we’ll be able to look at those fainter auroras too,” said Gladstone.
The planning and practicing that will take place over the next eight years will set the stage for the epic of discovery that will follow, as JUICE provides an unprecedented tour of the Jovian system. Gladstone can’t wait to get started.
“There’s a lot of great stuff to learn,” he said. “With all the variety JUICE is going to see and do, it’s going to be exciting once it gets there.”
NAIROBI, Kenya (AP) — The body of Ugandan Olympic athlete Rebecca Cheptegei — who died after being set on fire by her partner in Kenya — was received Friday by family and anti-femicide crusaders, ahead of her burial a day later.
Cheptegei’s family met with dozens of activists Friday who had marched to the Moi Teaching and Referral Hospital’s morgue in the western city of Eldoret while chanting anti-femicide slogans.
She is the fourth female athlete to have been killed by her partner in Kenya in yet another case of gender-based violence in recent years.
Viola Cheptoo, the founder of Tirop Angels – an organization that was formed in honor of athlete Agnes Tirop, who was stabbed to death in 2021, said stakeholders need to ensure this is the last death of an athlete due to gender-based violence.
“We are here to say that enough is enough, we are tired of burying our sisters due to GBV,” she said.
It was a somber mood at the morgue as athletes and family members viewed Cheptegei’s body which sustained 80% of burns after she was doused with gasoline by her partner Dickson Ndiema. Ndiema sustained 30% burns on his body and later succumbed.
Ndiema and Cheptegei were said to have quarreled over a piece of land that the athlete bought in Kenya, according to a report filed by the local chief.
Cheptegei competed in the women’s marathon at the Paris Olympics less than a month before the attack. She finished in 44th place.
Cheptegei’s father, Joseph, said that the body will make a brief stop at their home in the Endebess area before proceeding to Bukwo in eastern Uganda for a night vigil and burial on Saturday.
“We are in the final part of giving my daughter the last respect,” a visibly distraught Joseph said.
He told reporters last week that Ndiema was stalking and threatening Cheptegei and the family had informed police.
Four in 10 women or an estimated 41% of dating or married Kenyan women have experienced physical or sexual violence perpetrated by their current or most recent partner, according to the Kenya Demographic and Health Survey 2022.
TEL AVIV, Israel (AP) — A rare Bronze-Era jar accidentally smashed by a 4-year-old visiting a museum was back on display Wednesday after restoration experts were able to carefully piece the artifact back together.
Last month, a family from northern Israel was visiting the museum when their youngest son tipped over the jar, which smashed into pieces.
Alex Geller, the boy’s father, said his son — the youngest of three — is exceptionally curious, and that the moment he heard the crash, “please let that not be my child” was the first thought that raced through his head.
The jar has been on display at the Hecht Museum in Haifa for 35 years. It was one of the only containers of its size and from that period still complete when it was discovered.
The Bronze Age jar is one of many artifacts exhibited out in the open, part of the Hecht Museum’s vision of letting visitors explore history without glass barriers, said Inbal Rivlin, the director of the museum, which is associated with Haifa University in northern Israel.
It was likely used to hold wine or oil, and dates back to between 2200 and 1500 B.C.
Rivlin and the museum decided to turn the moment, which captured international attention, into a teaching moment, inviting the Geller family back for a special visit and hands-on activity to illustrate the restoration process.
Rivlin added that the incident provided a welcome distraction from the ongoing war in Gaza. “Well, he’s just a kid. So I think that somehow it touches the heart of the people in Israel and around the world,“ said Rivlin.
Roee Shafir, a restoration expert at the museum, said the repairs would be fairly simple, as the pieces were from a single, complete jar. Archaeologists often face the more daunting task of sifting through piles of shards from multiple objects and trying to piece them together.
Experts used 3D technology, hi-resolution videos, and special glue to painstakingly reconstruct the large jar.
Less than two weeks after it broke, the jar went back on display at the museum. The gluing process left small hairline cracks, and a few pieces are missing, but the jar’s impressive size remains.
The only noticeable difference in the exhibit was a new sign reading “please don’t touch.”
VICTORIA – The British Columbia government is partnering with a bear welfare group to reduce the number of bears being euthanized in the province.
Nicholas Scapillati, executive director of Grizzly Bear Foundation, said Monday that it comes after months-long discussions with the province on how to protect bears, with the goal to give the animals a “better and second chance at life in the wild.”
Scapillati said what’s exciting about the project is that the government is open to working with outside experts and the public.
“So, they’ll be working through Indigenous knowledge and scientific understanding, bringing in the latest techniques and training expertise from leading experts,” he said in an interview.
B.C. government data show conservation officers destroyed 603 black bears and 23 grizzly bears in 2023, while 154 black bears were killed by officers in the first six months of this year.
Scapillati said the group will publish a report with recommendations by next spring, while an independent oversight committee will be set up to review all bear encounters with conservation officers to provide advice to the government.
Environment Minister George Heyman said in a statement that they are looking for new ways to ensure conservation officers “have the trust of the communities they serve,” and the panel will make recommendations to enhance officer training and improve policies.
Lesley Fox, with the wildlife protection group The Fur-Bearers, said they’ve been calling for such a committee for decades.
“This move demonstrates the government is listening,” said Fox. “I suspect, because of the impending election, their listening skills are potentially a little sharper than they normally are.”
Fox said the partnership came from “a place of long frustration” as provincial conservation officers kill more than 500 black bears every year on average, and the public is “no longer tolerating this kind of approach.”
“I think that the conservation officer service and the B.C. government are aware they need to change, and certainly the public has been asking for it,” said Fox.
Fox said there’s a lot of optimism about the new partnership, but, as with any government, there will likely be a lot of red tape to get through.
“I think speed is going to be important, whether or not the committee has the ability to make change and make change relatively quickly without having to study an issue to death, ” said Fox.
This report by The Canadian Press was first published Sept. 9, 2024.
