SpaceX’s 1st Starlink launch of 2021 is now set for Wednesday – EarthSky



googletag.cmd.push(function() { googletag.display(‘post_link_unit’); });


Rocket with four legs extended landing on a plume of flame on a ship.Rocket with four legs extended landing on a plume of flame on a ship.

A Falcon 9 landing in 2017. Image via SpaceX.

SpaceX today again delayed the launch of its first set of controversial Starlink satellites for 2021. The launch to low-Earth orbit was originally scheduled for January 18, then for today, January 19. Now it’s scheduled for Wednesday, January 20, at 8:02 EST (13:02 UTC; translate UTC to your time) from Launch Complex 39A at the Kennedy Space Center in Florida. The newest set of 60 Starlink satellites will launch on SpaceX’s tried and true Falcon 9 rocket. You can watch the launch live at SpaceX’s website.

This launch, called Starlink 17, is to be the first of many Starlink launches in 2021, as SpaceX moves toward its goal of placing tens of thousands of these satellites in orbit with the intention of providing global high-speed broadband internet access. 2020 was a historic year for SpaceX, which included two different astronaut missions to the International Space Station — the first for a commercial company. It was also SpaceX’s busiest launch year to date, achieving a record 26 flights and smashing the previous record of 18 set in 2018. SpaceX plans to launch 40 rockets between its west and east coast launch sites following Starlink 17 in the new year.

Recovery efforts for the Falcon 9’s first stage begin about 45 minutes after liftoff. SpaceX’s main drone ship, Of Course I Still Love You, is currently undergoing maintenance; its backup ship called Just Read the Instructions will be waiting in the Atlantic Ocean for the stage, where it will land. If successful, the landing will mark the 72nd recovery of a first stage booster for the California-based rocket manufacturer.

The Falcon 9’s reuseable first stage previously supported seven other missions.

SpaceX is also expected to continue its tradition of recovering the Falcon 9’s payload fairing, or nose cone, on this flight. As they fall down to Earth in two pieces, two net-equipped boats — called GO Ms. Tree and GO Ms. Chief — wait nearby and prepare to snag the fairings. And while both pieces are outfitted with software that helps them aim for the recovery zone, the following process is not always the same. If they land in the outstretched nets of GO Ms. Tree and GO Ms. Chief, they can safely be hauled away. But if they make a gentle parachute-landing in the open water, the boats will scoop the fairings up out of the ocean. Making a midair catch is difficult and dependent upon several factors, like weather and winds, so it’s avoided. The decision between making a net-catch or scoop-catch is typically made the day of launch.

The curve of the Earth as seen from orbit, with 16 tiny streaks (Starlink satellites), each labeled with a number.The curve of the Earth as seen from orbit, with 16 tiny streaks (Starlink satellites), each labeled with a number.

Astronauts in the International Space Station photographed the southern lights and a train of 16 Starlink satellites (each with a unique ID number) on April 13, 2020 over the Southern Ocean off the coast of Antarctica. Image via ISS/NASA. Also see this video.

Starlink controversy within the astronomy community. Despite the promise of global internet access, both professional and amateur astronomers are fearful that the SpaceX Starlink satellites  which can be glimpsed as “constellations” of moving “stars”  will disrupt observations of the night sky. The National Science Foundation and the American Astronomical Society released a report on the situation in August 2020, following discussions among more than 250 experts at the virtual Satellite Constellations 1 (SATCON1) workshop.

SpaceX recently outfitted some Starlink satellites with a blackened sunshade  called VisorSat that the company hopes will reduce the satellite’s apparent brightness by reducing the amount of sunlight that’s reflected. That’s just one of six suggestions proposed by the SATCON1 team.

Initial efforts at mitigating the spacecraft’s impact involved launching a prototype Starlink satellite later dubbed DarkSat earlier in 2020, which featured a black antireflective coating. Recent ground-based observations of DarkSat in orbit found it half as bright as a standard Starlink satellite, which is a good improvement, according to experts, but still far from what astronomers say is needed. Jeremy Tregloan-Reed, a University of Antofagasta astronomer on the observational team that assessed the prototype, commented:

I would not consider DarkSat as a victory but instead a good step in the right direction.

The Federal Communications Commission has granted SpaceX permission to launch as many as 12,000 of the flat-panel broadband satellites, but the company has indicated that it intends to send up to 30,000. With those plans  as well as Amazon’s Project Kuiper aiming for 3,236 satellites and OneWeb, a now-bankrupt company recently acquired by the United Kingdom government, perhaps striving for 2,000  the scale of astronomy’s satellite-constellation problem will only increase.

19 thin bright lines crossing a section of starry sky from side to side.19 thin bright lines crossing a section of starry sky from side to side.

A time-lapse image shows the passage of a Starlink satellite cluster, creating bright streaks through a telescope’s field of view at the Cerro Tololo Inter-American Observatory of Chile in November 2019. Image via CTIO/NOIRLab/NSF/AURA and DECam DELVE Survey.

If everything goes as planned, this could mark the first of two SpaceX launches from Florida this week (SpaceX successfully launched the Turksat 5A mission via its Falcon 9 on Jan. 7). Later, on January 21, Falcon 9 rocket will launch the Transporter 1 rideshare mission with dozens of tiny satellites for commercial and government customers, and might even cap off the month with another Starlink mission, if not in early February.

Bottom line: SpaceX intends to launch tens of thousands of Starlink satellites, with lifespans of around 5 years, into low-Earth orbit. The goal is global internet access. Astronomers are concerned. Here’s how to watch the launch now scheduled for Wednesday, January 20.

Read more from EarthSky: Will SpaceX’s Starlink satellites ruin stargazing?

Read more from SpaceX will launch its 1st Starlink satellites of 2021 on Wednesday

Lia RoviraLia Rovira

Laisser un commentaire