''Humanity Star'' was a reflective

passive satellite {{about, the satellite by its functional type, the satellite by its orbital parameters, :Satellites by orbit Categories by type ...

designed to produce visible, pulsing

flares A flare, also sometimes called a fusée, fusee, or bengala, bengalo in several European countries, is a type of pyrotechnic that produces a bright light or intense heat without an explosion. Flares are used for distress signaling, illuminatio ...

. The satellite was launched into orbit by an Electron rocket on 21 January 2018 and entered into the atmosphere on 22 March 2018. The reaction to ''Humanity Star'' was mostly negative by astronomers, as it interfered with their observations.

Design

''Humanity Star'' was designed to produce

visible from Earth. The satellite was shaped like a geodesic sphere about in diameter, with its 76 reflective panels on the shape make it looks similar to a large disco ball. It is made out of

carbon fiber Carbon fiber-reinforced polymers (American English), carbon-fibre-reinforced polymers ( Commonwealth English), carbon-fiber-reinforced plastics, carbon-fiber reinforced-thermoplastic (CFRP, CRP, CFRTP), also known as carbon fiber, carbon comp ...

and weigh . According to Rocket Lab, ''Humanity Star'' was meant to be "a bright symbol and reminder to all on Earth about our fragile place in the universe".

Launch and orbit

''Humanity Star'' was launched on 21 January 2018 at 01:43

UTC Coordinated Universal Time (UTC) is the primary time standard globally used to regulate clocks and time. It establishes a reference for the current time, forming the basis for civil time and time zones. UTC facilitates international communica ...

from Rocket Lab Launch Complex 1, located on the Māhia Peninsula of New Zealand. It orbited the Earth every 92 minutes in a

polar orbit A polar orbit is one in which a satellite passes above or nearly above both poles of the body being orbited (usually a planet such as the Earth, but possibly another body such as the Moon or Sun) on each revolution. It has an inclination of abo ...

of approximately in altitude. According to Rocket Lab, the satellite's orbit was expected to decay after nine months, eventually burning up completely in Earth's atmosphere. However, the satellite re-entered several months early on 22 March 2018 at about 13:15 UTC. The quick entry could be caused by the ''Humanity Star'''s low density, amplifying

atmospheric drag In fluid dynamics, drag, sometimes referred to as fluid resistance, is a force acting opposite to the direction of motion of any object moving with respect to a surrounding fluid. This can exist between two fluid layers, two solid surfaces, or b ...

effects. Because of its highly reflective surface, Rocket Lab claimed that ''Humanity Star'' could be seen by the

naked eye Naked eye, also called bare eye or unaided eye, is the practice of engaging in visual perception unaided by a magnification, magnifying, Optical telescope#Light-gathering power, light-collecting optical instrument, such as a telescope or microsc ...

from the surface of the Earth. Its apparent brightness was estimated to be

magnitude Magnitude may refer to: Mathematics *Euclidean vector, a quantity defined by both its magnitude and its direction *Magnitude (mathematics), the relative size of an object *Norm (mathematics), a term for the size or length of a vector *Order of ...

7.0 when half illuminated and viewed from a distance of , while its maximum brightness was estimated to be magnitude 1.6. The satellite was most likely to be visible in the night sky at dawn or dusk. Its orbit could be tracked by

Heavens-Above Heavens-Above is a non-profit website developed and maintained by Chris Peat as ''Heavens-Above GmbH''. The web site is dedicated to helping people observe and track satellites orbiting the Earth without the need for optical equipment such as bin ...

and the satellite's website.

Analysis

Initial reactions by astronomers were negative, since reflective objects in orbit interferes with astronomical observations. It has been described as an act of vandalism of the night sky, space

graffiti Graffiti (singular ''graffiti'', or ''graffito'' only in graffiti archeology) is writing or drawings made on a wall or other surface, usually without permission and within public view. Graffiti ranges from simple written "monikers" to elabor ...

, a "publicity stunt" and "glittery space garbage". Others however argue that flares by existing satellites and the ISS are much brighter than ''Humanity Star''. Alice Gorman postulates that ''Humanity Star'' and Elon Musk's Tesla Roadster are statements with very different but related messages: while ''Humanity Star'' may be seen as promoting a unifying vision and the Roadster as a reminder of inequality, "each tells the story of attitudes to space at a particular point in time."

References

External links

* {{Use dmy dates, date=January 2018 2018 in New Zealand 2018 controversies Passive satellites Spacecraft launched in 2018 Spacecraft which reentered in 2018 Satellites of New Zealand Spacecraft launched by Electron rockets

Design

Launch and orbit

Analysis

See also

References

External links