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NASA Artemis I Launch Countdown 101 – SciTechDaily

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Illustration of NASA’s Space Launch System rocket launching with Orion atop it from Launch Complex 39B at NASA’s modernized spaceport at Kennedy Space Center in Florida. Credit: NASA

Before the Artemis I mission launches on its way around the Moon, the launch team at Kennedy Space Center in Florida and supporting teams across the country will begin the launch countdown about two days before liftoff.

The launch countdown contains “L Minus” and “T Minus” times. “L minus” indicates how far away we are from liftoff in hours and minutes. “T minus” time is a sequence of events that are built into the launch countdown. Pauses in the countdown, or “holds,” are built into the countdown to allow the launch team to target a precise launch window, and to provide a cushion of time for certain tasks and procedures without impacting the overall schedule. During planned holds in the countdown process, the countdown clock is intentionally stopped and the T- time also stops. The L- time, however, continues to advance.

Members of the Artemis I Launch Team

Members of the Artemis I launch team participate in a countdown simulation inside the Launch Control Center’s Firing Room 1 at NASA’s Kennedy Space Center in Florida on February 3, 2020. Credit: NASA/Kim Shiflett

During the wet dress rehearsal test ahead of Artemis I launch, the test team may hold during the countdown as necessary to verify conditions before resuming the countdown, or use the test window or extend beyond it, if consumables and resources allow them to complete test objectives. The timing for some events is approximate and may differ slightly during testing on account of several planned operational demonstrations tied to specific capabilities and test objectives. During the rehearsal, controllers will count down to T-1 minutes and 30 seconds and pause to demonstrate the ability to hold for up to 3 minutes, then resume until 33 seconds before when launch would occur, then pause the countdown. Then they will recycle back to ten minutes before launch and conduct a second terminal countdown to approximately 9.3 seconds before launch, then end the countdown. Teams may refine the coundown timeline ahead of launch based on experience with the rehearsal test.

Artemis I at Launch Pad 39B Sunrise 2

A view of the Artemis I Space Launch System (SLS) and Orion spacecraft just before sunrise at Launch Complex 39B at NASA’s Kennedy Space Center in Florida on March 23, 2022. Credit: NASA/Ben Smegelsky

Below are some of the key milestones that take place for the Space Launch System rocket, Orion spacecraft, and ground systems after the countdown begins.

L-45 hours and counting

  • The launch team arrives on their stations and the countdown begins (L-45, 40 minutes hours)
  • Fill the water tank for the sound suppression system (L-45 hours)
  • The Orion spacecraft is powered up (L-40 hours)
  • The core stage is powered up (L-34 hours, 45 minutes)
  • Final preparations of the four RS-25 engines (L-30 hours, 50 minutes)
  • The Orion crew module hatch is closed (L-30 hours, 5 min)
Artemis I at Launch Pad 39B Moon Visible 1

The Moon serves as a background for the Artemis I SLS and Orion spacecraft at Launch Complex 39B at NASA’s Kennedy Space Center in Florida on March 21, 2022. Credit: NASA/Ben Smegelsky

L-30 hours and counting

  • Leak checks are completed on the Orion spacecraft and the hatch on the launch abort system is closed (L-28 hours, 50 minutes)
  • The crew access arm is retracted (L-26 hours, 5 minutes)
  • Side flame deflectors are moved into place (L-21 hours)

L-14 hours and counting

  • The interim cryogenic propulsion stage (ICPS) is powered up (L-12 hours, 45 minutes)
  • All non-essential personnel leave Launch Complex 39B (L-12 hours)

L-8 hours, 40 minutes and counting

  • Built in countdown hold begins and lasts approximately one- and one-half hour (L-8 hours, 40 minutes)
  • The launch team conducts a weather and tanking briefing (L-8 hours, 40 minutes)
  • Launch team decides if they are “go” or “no-go” to begin tanking the rocket (L-7 hours, 40 minutes)
  • Core stage liquid oxygen (LOX) chilldown (L-7 hours, 20 minutes)

L-7 hours and counting

  • Core stage LOX slow fill start (L-6 hours, 25 minutes)
  • Core stage LOX fast fill start (L-6 hours, 10 minutes)
  • Core stage liquid hydrogen (LH2) chilldown start (L-6 hours, 5 minutes)
  • Core stage LH2 slow fill start (L-5 hours, 55 minutes)
  • Core stage LH2 fast fill (L-5 hours, 40 minutes)
Artemis I at Launch Pad 39B 7

Standing atop the mobile launcher, NASA’s SLS rocket is photographed at Launch Complex 39B at the agency’s Kennedy Space Center in Florida on March 18, 2022. Credit: NASA/Kim Shiflett

L-4 hours, 30 minutes and counting

  • ICPS LH2 chilldown (L-4 hours, 25 minutes)
  • Orion communications system activated (RF to mission control) (L-4 hours, 20 minutes)
  • Core stage LH2 topping start (L-4 hours, 30 minutes)
  • Core stage LH2 replenish start (L-4 hours 25 minutes)
  • ICPS LH2 fast fill start (L-4 hours)

L-3 hours, 30 minutes and counting

  • Core stage LOX topping start (L-3 hours, 25 minutes)
  • ICPS LOX chilldown start (L-3 hours, 20 minutes)
  • ICPS LH2 validation and leak test start (L-3 hours, 15 minutes)
  • Core stage LOX replenish start (L-3 hours, 18 minutes)
  • ICPS LOX fill start (L-3 hours, 10 minutes)
  • ICPS LH2 tank topping start (L-3 hours)
  • ICPS/<span class="glossaryLink" aria-describedby="tt" data-cmtooltip="
    SLS
    NASA's Space Launch System (SLS) is part of NASA's deep space exploration plans and will launch astronauts on missions to an asteroid and eventually to Mars. As the SLS evolves, the launch vehicle will to be upgraded with more powerful versions. Eventually the SLS will have the lift capability of 130 metric tons, opening new possibilities for missions to places like Saturn and Jupiter.

    ” data-gt-translate-attributes=”["attribute":"data-cmtooltip", "format":"html"]”>SLS telemetry data verified with mission control and SLS Engineering Support Center (L-2 hours, 50 minutes)

  • ICPS LH2 replenish start (L-2 hours, 35 minutes)
  • ICPS LOX validation and leak test start (L-2 hours, 30 minutes)
  • ICPS LOX topping start (L-2 hours, 20 minutes)
  • ICPS LOX replenish start (L-2 hours, 10 minutes)

L-40 minutes and holding

    • Final <span class="glossaryLink" aria-describedby="tt" data-cmtooltip="
      NASA
      Established in 1958, the National Aeronautics and Space Administration (NASA) is an independent agency of the United States Federal Government that succeeded the National Advisory Committee for Aeronautics (NACA). It is responsible for the civilian space program, as well as aeronautics and aerospace research. It's vision is &quot;To discover and expand knowledge for the benefit of humanity.&quot;

      ” data-gt-translate-attributes=”["attribute":"data-cmtooltip", "format":"html"]”>NASA test director briefing is held

    • Built in 30-minute countdown hold begins

L-15 minutes and holding

  • The launch director polls the team to ensure they are “go” for launch

T-10 minutes and counting

  • Orion ascent pyros are armed (T-6 minutes)
  • Orion set to internal power (T-6 minutes)
  • Core stage LH2 terminate replenish (T-5 minutes, 57 seconds)
  • Core stage auxiliary power unit starts (T-4 minutes)
  • Core stage LOX terminate replenish (T-4 minutes)
  • ICPS LOX terminate replenish (T-3 minutes and 30 seconds)
  • ICPS switches to internal battery power (T-1 minute, 56 seconds)
  • Core stage switches to internal power (T-1 minute, 30 seconds)
  • ICPS enters terminal countdown mode (T-1 minute, 20 seconds)
  • ICPS LH2 terminate replenish (T-50 seconds)
  • Ground launch sequencer sends “Go for automated launch sequencer” command (T-33 seconds)
  • Core stage flight computer to automated launching sequencer (T-30 seconds)
  • Hydrogen burn off igniters initiated (T-12 seconds)
  • Ground launch sequencer sends the command for core stage engine start (T-10 seconds)
  • RS-25 engines startup (T-6.36 seconds)

T-0

  • Booster ignition, umbilical separation, and liftoff

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The body of a Ugandan Olympic athlete who was set on fire by her partner is received by family

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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.

Kenya’s high rates of violence against women have prompted marches by ordinary citizens in towns and cities this year.

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.

The Canadian Press. All rights reserved.

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The ancient jar smashed by a 4-year-old is back on display at an Israeli museum after repair

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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.”

The Canadian Press. All rights reserved.

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B.C. sets up a panel on bear deaths, will review conservation officer training

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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.

The Canadian Press. All rights reserved.

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