The Falcon Launch Vehicle - An Attempt at Making Access to Space More Affordable, Reliable and Pleasant

Falcon is a mostly reusable, two stage, liquid oxygen and kerosene powered launch vehicle being built by Space Exploration Technologies (SpaceX) from the ground up. The vehicle is designed above all for high reliability, followed by low cost and a benign flight environment. Launched from Vandenberg, a standard Falcon can carry over 470 kg to a 700 km sun-synchronous orbit and a heavy Falcon can deliver 1450 kg to the same orbit. To minimize failure modes, the vehicle has the minimum pragmatically possible number of engines (two) and stage separation events (one), as well as dual redundant avionics. Since the first stage is recovered via parachute to a water landing, approximately 80% of the vehicle mass is reusable as compared with 90% for the Space Shuttle. The costs, which nominally assume no advantage for recovery, are $6M for a standard Falcon and$10M for a heavy Falcon. First launch is scheduled for January 22nd, 2004 from Vandenberg, carrying a US government satellite

Panel Discussion

Panelists will be challenged to offer and defend their opinions on the value of small satellites. Conference attendees are encouraged to submit topical questions at the registration booth

Epidemiological and Immunological Features of Obesity and SARS-CoV-2

Obesity is a key correlate of severe SARS-CoV-2 outcomes while the role of obesity on risk of SARS-CoV-2 infection, symptom phenotype, and immune response remain poorly defined. We examined data from a prospective SARS-CoV-2 cohort study to address these questions. Serostatus, body mass index, demographics, comorbidities, and prior COVID-19 compatible symptoms were assessed at baseline and serostatus and symptoms monthly thereafter. SARS-CoV-2 immunoassays included an IgG ELISA targeting the spike RBD, multiarray Luminex targeting 20 viral antigens, pseudovirus neutralization, and T cell ELISPOT assays. Our results from a large prospective SARS-CoV-2 cohort study indicate symptom phenotype is strongly influenced by obesity among younger but not older age groups; we did not identify evidence to suggest obese individuals are at higher risk of SARS-CoV-2 infection; and remarkably homogenous immune activity across BMI categories suggests immune protection across these groups may be similar

SARS-CoV-2 antibodies protect against reinfection for at least 6 months in a multicentre seroepidemiological workplace cohort

Identifying the potential for Severe Acute Respiratory Syndrome : Coronavirus 2 (SARS-CoV-2) reinfection is crucial for understanding possible long-term epidemic dynamics. We analysed longitudinal PCR and serological testing data from a prospective cohort of 4,411 United States employees in 4 states between April 2020 and February 2021. We conducted a multivariable logistic regression investigating the association between baseline serological status and subsequent PCR test result in order to calculate an odds ratio for reinfection. We estimated an odds ratio for reinfection ranging from 0.14 (95% CI: 0.019 to 0.63) to 0.28 (95% CI: 0.05 to 1.1), implying that the presence of SARS-CoV-2 antibodies at baseline is associated with around 72% to 86% reduced odds of a subsequent PCR positive test based on our point estimates. This suggests that primary infection with SARS-CoV-2 provides protection against reinfection in the majority of individuals, at least over a 6-month time period. We also highlight 2 major sources of bias and uncertainty to be considered when estimating the relative risk of reinfection, confounders, and the choice of baseline time point and show how to account for both in reinfection analysis