NASA's new moon rocket arrived at the launch pad Wednesday ahead of its debut flight in less than two weeks.

The 322-foot (98-meter) rocket emerged from its mammoth hangar late Tuesday night, drawing crowds of Kennedy Space Center workers, many of whom were not yet born when NASA sent astronauts to the moon a half-century ago.

The rapid development of Low Earth Orbit (LEO) mega constellations has significantly contributed to several aspects of human scientific progress, such as communication, navigation, and remote sensing. However, unrestrained deployment of constellations has also strained orbital resources and increased spacecraft congestion in LEO, which seriously affects the safety of in-orbit operations of many space assets.

For the long-term and sustainable development of space activities in LEO regions, space environment stability must be maintained using more rational surveillance and governance mechanisms. In a review paper recently published in Space: Science & Technology, Jingrui Zhang from School of Aerospace Engineering, Beijing Institute of Technology, analyzed the research gap and facilitated the development of LEO mega constellations.

First of all, the author reviewed the current developments of typical LEO mega constellations, including Starlink, OneWeb, Iridium Next, Globalstar, and Flock. Taking SpaceX's Starlink as an example, it aims to build a LEO constellation containing 42,000 satellites to achieve global coverage, high-speed, large-capacity, and low-latency space-based global communication system. Starlink has shown excellent performance in related fields, such as international aviation and ocean transportation. Moreover, Starlink can be constructed as a powerful command and communication network and has already been an important symbol of the weaponization of outer space in the United States.

How do we make medicine last the extreme conditions of space exploration?

How would you manage a headache while flying to Mars?

You might try the Earth remedy of taking a painkiller. But on a 2-year round trip, how long would they last? And could you trust them?

Martian migraine

Access to medical supplies is a major concern for astronauts. Sleep issues, pain, congestion and allergies are all common complaints from those on extra-terrestrial missions.

The use of medication by American crewmembers on the International Space Station (ISS) was monitored between 2002 and 2012. And according to the data, astronauts used sleep tablets 10 times more often than earthlings. They also used ibuprofen for pain stemming from space flight pressure changes, higher carbon dioxide levels and joint issues.

Unfortunately, the longer the space flight, the higher the chances of experiencing acute illness. Common health problems for astronauts include a weakened immune system, bone decalcification and low blood pressure.

On Earth, most medicines expire within a year.